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Apply force/impulse to objects
I am trying to apply a force to certain objects via a self-made script.
Though I cannot find any option to do so in Blender. I could only find something equivalent in Blenders Game Engine: applyImpulse().
The goal is to apply an impulse to objects with a minimum mass after they reached a specific coordinate.
If there is no such function like adding an impulse, then I could also try to manipulate the current movement vector of the object according to its previous frames, but they are only saved within the cache right? I am also not aware how to retrieve this data.
I was also trying to just use some sort of Force Fields, but they don't show the effect I wish.


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Blender crashes when iterating over collection.all_objects
When I try to set a keyframe for every object in a collection with the script below, blender immediately crashes. I'm running this on a host-collection with 30 objects in it, so I don't think this should be such a memory hungry operation.
Does anybody have an idea why this could be happening?
def hideObj(obj, kf):
    obj.hide_viewport = True
    obj.hide_render = True
    obj.keyframe_insert(data_path = "hide_viewport", frame = kf)
    obj.keyframe_insert(data_path = "hide_render", frame = kf)

for obj in bpy.data.collections["HOST"].all_objects:
    hideObj(obj, 0)

Here's the error log
> I0315 18:37:41.637778  7144 device.cpp:45] CUEW initialization
> succeeded I0315 18:37:41.650597  7144 device.cpp:47] Found precompiled
> kernels I0315 18:37:41.667937  7144 device.cpp:68] HIPEW
> initialization failed: Error opening HIP dynamic library Error   :
> EXCEPTION_ACCESS_VIOLATION Address : 0x00007FF6280520FA Module  :
> blender.exe Thread  : 00001be8 Switching to fully guarded memory
> allocator. Blender 3.0.0 Build: 2021-12-03 00:44:02 Windows release

"hide_viewport" property cannot be animated so that line in your code is not doing anything but I don't know if it is causing the error.

try this:
for obj in bpy.data.collections["Host"].all_objects:

    if obj.type == "Mesh":
        hideObj(obj, 0)

because i could reproduce your crash if a camera is in the collection.

"hide_viewport" can definitely be animated. The problem apparently is a documented gotcha.
Answer from the blender dev team:

This is, unfortunately, a documented problem:
https://docs.blender.org/api/master/info_gotcha.html#unfortunate-corner-cases
Modifying the hide_viewport or hide_render properties on an object
will re-construct the collection object list. As such you are
enumerating over a list that might change which isn't permitted.

I ended up putting all objects into a dictionary and that solved the problem.
hostObjs = {}
for obj in host.all_objects:
    hostObjs[obj.name] = obj

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

sort: votes


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Exporting from Grease pencil to SVG with Holes does not work properly?
I am trying to export a shape that I made in blender to an SVG. I've converted the curve to SVG, but all the holes get filled in the process. The work around to that was to assign the inner curves to a material that has hold out checked. This allows for the holes to become transparent when being rendered, but it is just black when being exported to an SVG. Is there no way to have holes in a shape and export it to an SVG?

Is it possible to export shapes like this as SVGs using blender?
I want them to be filled as well. So exporting with fill is necessary.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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Does Blender have a built-in basic material library?
I'm an absolute Blender Noob and was wondering if Blender has a basic material library built-in. I understand that I could make my own materials, but that's right now way over my head. I am looking for some basic wood materials and textures that I can use as a starting point, without having to re-invent the wheel.

No it doesn't, but there are many free resources online and some addons such as Blenderkit which can automatically download the textures for you.

Blender Studio released the Charge materiel library; it's phenomenal.  Highly recommend looking up some tutorials on the Asset browser, it's super useful.

Yes, it does. There’s a built-in add-on called “Material Library” that you can enable. Once you have, it shows up in a panel under the Materials tab of the Properties editor. Select the “Sample materials” bank.
You may find that set of materials, a bit lacking, and in that case, I also recommend the third-party BlenderKit add on, which connects to BlenderKit.com, an online database of materials, objects, scenes, worlds, etc.

I was about to close this as too broad for us. but yes, this is a very fuzzy area, and this answer is helpful in the archive, so thanks for holding me off.


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Surface blotchy when uploaded to Speckle
What steps should I take in Blender in order to remove the blotches when object is uploaded to Speckle?
Thanks.
Doug


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Struggling with transparent image textures and Shaders
I'm attempting to create low-poly playstation style models and I've encountered a rough patch in my process.I'd appreciate any assistance as I can't find any resources to assist with the issue.
for this model, I am attempting to use a transparent texture to provide a more convincing effect but when I attempt to use my old node setup to achieve a flat cell shaded style look the texture loses its transparency. My question is, is there any way to achieve similar results for the shader without negating my transparent texture? My original node set up uses Color ramp and Multiply which seemingly makes the texture's transparent elements appear as white.
Included are photos of my usual node setup and the only node setup I could make that would respect the image texture's transparency. any help is much appreciated as I'm a beginner and I feel so far out of my depth!

Hello, it's hard to understand, maybe show a reference image of the real object, also an image of your object, maybe share your file?


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How do I separate parts of a mesh but keep them as one parented object?

I'm guessing the answer to my question is somewhere but I can't find it because I probably don't know the correct terms...
I am trying to learn how to keep separated constituent meshes/parts of a single object parented in one object. For example, you can see that the 'jacketMesh_REPLACEME' appears as one file in Effect House. Each FBX file is denoted by a white cube. But there are ten separate meshes comprising the jacket. Each mesh has a blue icon next to it. The jacket is separated into sleeve, pocket, etc. The meshes need to be separate so I can apply different materials to each one. But these meshes all need to react to each other when the object is transformed to create a realistic effect, and there can't be gaps between the meshes.
Do I separate all the parts and then save them as one file, parented to the body rig? Or do I need to parent each separate part to each other and finally to the body rig? What are the steps involved? How did they achieve what is displayed in the picture?
The Effect House tutorial video link is here: https://effecthouse.tiktok.com/learn/library/template-tutorials/clothing-try-on

Each face of an object is assigned to one material slot (unless the object has none, in which case all faces will become assigned to the first material slot added to the object), and an object can have many material slots. So faces, even conjoined ones, can be assigned different materials while being within the same object.
I don’t know what you mean about saving the shirt as a file parented to the rig. That doesn’t make sense. What you do want to do is join the shirt piece objects together into one object, then probably go into edit mode and do a Select All -> Merge: By Distance to connect the pieces. Rigging is a separate question, so I won’t answer it here. One thing to note is that if the shirt shares one material already, and that material has one image texture, but the UV maps for the different pieces have different names, you’ll have to rename the maps to have the same name, or make sure each section of the shirt uses the right one (the first option being less complicated by far).
See this answer for a more detailed description of how materials and textures work.


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Shadowcatcher on a plane with a alpha image cuts my torus in half
I have a plane with an alpha image of a building but i only want shadows on the plane from objects landing on it, But were ever my objects intersect with the plane they got cut of.
And if i activate the holdout the shadows disappear

How can i fix this??

Maybe upload your blend file

If you have a chance to use Eevee try this tricky thing ...

For more details see https://blender.stackexchange.com/a/311251/2214

I would likes to courage downvoter to briefly comment what is wrong with my answer So I can improve oř explaine. Just a downvoting doesnt help to anybody. Thanks


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How to move a rigged up model in Blender (Human Hand)?
I'm new to the animating side of Blender, and have a hand model (pre-rigged) that I'm trying to bend into a peace sign shape. However, whenever I try to move the rigged bone portions, the hand becomes deformed and warped, and the hand doesn't bend properly.
If someone is able to bend this rigged up hand into a peace sign for me, I would be forever grateful.
https://www.mediafire.com/file/11ul8a3votkz8c4/Hand_Main.blend/file

This site is not for asking other people to do work for you. I strongly recommend you remove that aspect of your question. Meanwhile, I’ll try to look at your rig and see what’s wrong. You also generally want to attach a screenshot instead of just having people download a file before they can help. In turn, use blend-exchange.com to share your blend file on this site, whenever the size is small enough.

it seems to bend correctly, could you please be more specific, maybe show a picture?

Best I can tell, the rig is mostly normal, except that you've posed the bone thumb.003 when it should be zeroed, and "low-level" bones are visible when "high-level" control bones are present. To fix that:

In the 3D Viewport editor, select the armature.
Go into Pose Mode.
Press N to show the properties panel.
Hover over the quaternion rotations, and press backspace.
After that is done...
In the Properties editor, go to the Armature data-block tab.
In the Bone Collections panel, hide Layer 2 by clicking the eye next to it.

With only the control bones visible in Pose mode, all you have to do is select one and rotate it. The thumb control bone curls the thumb with its X rotation, while all the other finger control bones curl the fingers with their Z rotation.
For more information, see the blender manual page on armature posing.


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Model breaks on FBX import
I'm having an issue trying to import a simple rigged hand model (made with 3DS Max few years ago).
The model shows correctly when i open it with a 3D viewer like Autodesk FBX Review, the animation and the rig seem perfectly fine.
But when i import it with Blender, the bones and the hands are completely messed up on the position, rotation and even scale.

I already got this issue with previously made FBX on 3DS Max when a hierarchy is implied, even without any kind of rigging/skinning.
I don't have access to 3DS Max anymore but i need to use this model.
Is there any import options i'm missing to get a proper import ?
Thanks.

Well after some search i found about this addon "Better Fbx Importer & Exporter" (28$ USD) that solves the issue. Too bad blender isn't able to do it natively, or at least for free. Cheers.

After importing FBX try this:

Select the armature and switch to Pose Mode
Press A to select all bones
Pose > Clear Transform > All


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How to import and merge multiple meshes with different textures into one mesh
Is there any way to merge multiple meshes with different textures into one mesh(USDz)?
Right now I cannot even import two meshes with different textures into Blender....
Here are two files: https://drive.google.com/drive/folders/1QBCLCyrQ_9jvIKBFIZKEEITx5ebNjS18?usp=share_link
Thank you

Hello and welcome. While files, images, and external videos or links may be helpful additions they should not be the only way to obtain information about your issue. Don't make understanding your question rely on downloading a file, watching a video or visiting an external site. Use the builtin tools to upload images or gifs, along with thoroughly explaining the problem in written form so it can be indexed and searched for thus helping future visitors with similar issues.

The problem with your two files is, there are no unique names for materials and textures. This way after importing one of them, the second one automatically uses the same image texture as the first one, because since these files are complete scene descriptions, to Blender it looks like there is one image texture in the scene and both objects use it. I do not know where you got them from, when I use different files they usually have different names for materials and image textures so this issue does not occur.
But in your case, to avoid the double use of textures, there are two possible ways to go:

You import one USDz file into a new scene, and save this as a Blender file. Then you create another new scene, import the second USDz file. Then you go to File > Append and explore the previously saved file to append the collection that's in there. This way, Blender will rename the material and image texture to separate them from the other.

This is the easiest way I think. Another would be:

Create a new scene and save it before importing anything. Then when importing the first USDz file, go to the import options on the right and scroll all the way down to Import Textures and change it from Packed to Copy. By default it then uses the relative path "//textures/" (which only works if you saved the file beforehand to determine the path this folder is relative to).

After import, you have to go to the "textures" folder and rename the image file. Then back in Blender, in the Shader Editor you have to change the Image Texture in the material of the object to the one with the new name with Open. But now the datablock with the old image and filename still remains in the scene, so to get rid of it go to File > Clean Up > Recursive Unused Data-Blocks. Now you can import the second USDz file into the scene and it will get his own texture.

Thank you for this very detailed answer! I chose the second one, it works very well for me.

Thank you!! And thank you, @Oscar for asking the question. Huge help! The first option worked beautifully for me when importing two USDZ files I made via photogrammetry.


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animation nodes mix vector doesnt work
How i can fix it?
I trying to make some morph with metaballs

Some nodes just don't accept lists. Nodes that accepts lists are said to be vectorized, on this case, this not isn't vectorized. You can either use another node to achieve the same result, or use a loop as follows:

@StanislavVonSyktyvkarian Please accept the answer if it answers your question.

Maybe you can achieve same results with offset nodes


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De-noise pre-rendered image starting from frame 0
So, I have some pre-rendered 3840x2160 images from another program called Source Filmmaker, and I want to de-noise them using Blender. SFM exports images starting with frame number 000000, regardless of how many digits the last frame has. In this case I want to de-noise from frame #000000 to frame #015983. I was able to do this using the de-noise node in Blender 2.81, which worked successfully with SFM's noise samples. However, it seems Blender starts at frame 1 by default, so how can I be sure that Blender starts at frame 0 and the frame numbers match?

Does this answer your question? How to set the frame range for rendering?

Not really, I'm looking for how to do it in animation and image sequence properties and ensure it starts from frame 0.

The Image node should have a Start Frame property when loading an image sequence.

I'd rename the image sequence, 2 seconds, done.


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Exporting Text with Curve Modifier Animation to Unity 3D
I'm making a simple text animation following this tutorial: https://www.youtube.com/watch?v=bF3O4qbaMqs. Basically, it's making text running in circles by applying a circle/bezier curve modifier on it. So when I change the x value of the location of the text, it runs in circle, which works jsut fine in Blender. However, when I keyframe everything and move them into Unity, the curve modifier doesn't work and the text is just moving along the x-axis. How should I fix this in Blender, so I can have the text running in circle effect in Unity?

Please read https://blender.stackexchange.com/questions/57531/fbx-export-why-there-are-no-materials-or-textures

Blender modifiers will not work in a different program nor should you assume that the animations will either even though the basic keyframe do. You're could rig the object and bake the animation or shape key. But in this case though, just rotate the text GameObject in Unity around the circle center point. The right approach here is to model meshes in Blender and make objects move in Unity.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


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Unity Mecanim animations for Blender Rig
I created this fully rigged character with face blend shapes that I've used for Unity.
I used mecanim animations and lip sync for the character in Unity. Now I want this character doing similar things in WebGL in three.js, using FBX Loader. How do I get the Unity animations for my Blender file so I can have the same animations?

Are you asking how to export FBX from Unity, or from Blender? Do you have all of the animations working in Blender?

I mean how to export fbx from Unity for Blender. My animation works in Unity. I don't have the animations in Blender at all. The mecanim animations are in Unity, stored with a xxx.fbx.meta file and a obj model file.

Ah I see. Sorry I only know about the Blender -> three.js part of this. :)

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


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Reference Editor in Blender?
Can we import any character as reference in blender ? So that if there are any changes in the mesh/uv character can be replaced in rig file.


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Light linking not showing up
I've got Blender 4.0.2 but there is no Light Linking or Shadow Linking in the object properties. There's not even the 'Shading' tab. Any ideas why? Does it need enabling?

Do you have a light selected in the outliner? - It's there on this machine under the Shading dropdown. This is the Blender Manual entry about light linking.

Are you using Cycles and not another render engine?


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How would I make an image texture repeat along many walls without having to select each face manually?
Hello I'm fairly new to Blender and I am trying to make this maze have textures on the walls. I want to put this image on every wall in this mesh, but I don't want to have to manually select and/or map every face to the texture. I would like for it to fit on each face as shown in the image, but I'm not really concerned with little stretching. I would also like a good way to choose specific areas to have a different wallpaper If I decide to change some areas.

Ok I found a solution that works for me. I installed the Magic UV add on and selected the face and right clicked and navigated to UV Unwrap Faces > Copy/Paste UV > Copy > [All]
Then I set my view to look directly at the model on the y axis in wireframe view and set the Select Mode to Face and dragged a box down the middle avoiding the floor and ceiling. Then I right clicked and navigated to UV Unwrap Faces > Copy/Paste UV > Paste > [All] and this achieved my desired result.

You can use a geometry nodes that selects all faces whose normal Z is zero.
See: all walls got the "wall" material and became red.
Then you just need to adjust the shader node for stretching, repeating, whatever. (You might want to smart UV unwrap and use the UV coordinates)

PS: you may create a mapping for these faces based on the answer to this question if you don't want to get into UV.
How to mapping Texture image in all Voronoii Cells?

Thank you for the answer. I think I understand pretty well what is happening with the geometry nodes. I did struggle to get my texture lined up on each face properly as each face's UV map seemed to be shrunken to the bottom left corner of the image. I tried to understand what was happening in the question you linked in the bottom, but even researching further into it I still don't understand. Thank you so much for your help!


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How can I create custom collision for this mesh
I don't know how to create custom collision for this helmet I was created in blender.I just only want to create collision on surface of this mesh .

Here is my blender FILE

Hello and welcome. Please don't post the same question more than once. If your previous question was put on hold, address the raised issues by editing it so it can be reopened rather than post a new one, otherwise see What should I do if no one answers my question?

Ok . I got it . Thanks you

select the faces you want to collide in the edit mode and shift D to duplicate those faces then with those faces selected click the right mouse button and select separate => selection, make those faces into a separate object, then select this object go to physic tab toggle collision tab, and hide this object in render, you will have a collision proxy for your helmet and if your helmet mesh has too many faces you can add a decimate modifier to lower the faces count as long as it keeps the shape.

It that correct ? https://i.imgur.com/CETd8eF.png

I did not saw anychange in it . Can you guide me please

Welcome and thanks for your answer. It might be clearer if you show some screenshots while you talk through the process. There's nothing wrong with what you've posted here, but some may struggle to follow a block of text like this, and we try to focus on high quality answers, that's all. Have a good day :)


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Does the highpoly mesh have to have a clean topology, or the exact subdivided version of the lowpoly for which it will be used as a baking source?
I dyntopo in sculpting a lot and use that Dyntopoed high poly mesh as the baking source for the retopoed lowpoly. I have tested it a few times, never had issues with with the results. But I was wondering if this is a pernicious approach, that there might be unknown drawbacks somewhere in the bushes waiting to bite me in the rear at any given time. I appreciate any educated opinions on this.

No, the high poly doesn't have to have clean topology.
There are a few different ways that we can get good, smooth normals.  One way is to use clean topology.  The other way is to just use so many vertices that interpolation between those vertices doesn't really matter.  (These are continuous-- the more vertices you use, the less you have to care about topo, and the more careful you are with topo, the fewer vertices you can get away with.)
The whole reason for the high->low workflow that has become popular is to enable modelling without having to worry about topo at the same time.  So you use techniques like booleans or dynotopo, and then don't worry about the topo until you actually retopologize your mesh.
That said, a high poly does have to have enough vertex density to actually make this work!  If you just do some low poly booleans and then bake smooth shaded normals, you'll be baking in the exact same shading artifacts that you see on the high poly.  In order to get away with poor topo, a high poly needs to actually be high poly.


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How come the wiggles 2 addon work well in eevee but not cycles?
As I assign certain bones to wiggle, in eevee, the animation is pretty smooth and flawless.
In cycles however, the wiggle bones twitch badly...
I find it really odd as to what a render engine that is meant to affect lighting has anything to do with bone animation and physics simulation? How are they connected and is there a solution to this?


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Animating a progress bar to run along with a sun path study
I often render out videos of architecture projects to show the movement of sunlight over a day with Twinmotion. I then render out a video of a progress bar in Blender to match the number of frames, as well as the time of day to give some reference to the Suns movement. This is quite tedious as I often have to completely rebuild the progress bar animation, rewriting new timestamps as well as adjusting the frame count. I then use Blender to lay the progress bar over the sunstudy and rerender them together into one video.
I was wondering if there might be a way to streamline this with geometry nodes (or other blender tools).
It would be cool if I could define the start and finish times from my sun study, define how many timestamps there should be, adjust the frame count, and it would spit out a matching progress bar.
If anyone could drop a tip, a link, or reference on how to get started on such a project (or an aspect of it), I would be much obliged!!

specific problem you have and where you are stuck at.

@Chris we both have gold geonodes badges, why didn't the question close when we voted to close it? :D It seems OP doesn't request for the work to be done for him, just some starting tips, but that makes this question opinion-based; it also lacks focus, is there a specific part the OP needs help with? Sticking the progress bar to camera (just parent it to the camera), advancing the progress bar? Just scale a cuboid based on Scene time...

@MarkusvonBroady: I have no idea....and tbh i didn't even recognize that :D and i would love to solve/help with that question and we both could solve that (i think) but the way he asked he killed my will to help....and i didn't even downvote, just vote for close ;)

I don't understand the "discussion" here. For me, this question is perfectly fine. It boils down to this: how to create a progress bar with custom labels using Geometry Nodes - or is there another/easier way? Answer/hint: It is an easy task to create a simple progress bar in GN, but labeling might be a challenge. Idea: Maybe you can use a collection of pre-made label objects that you arrange on a mesh line. Parent the GN object in front of the camera and the overlay is done. Alternatively, you can write a small Python script that does the job.

Hi my dudes! Firstly, I was certainly not looking for someone to build this for me! Secondly, I was not aware that this forum is only there to ask a sole hyperspecific question about a problem.
Thank you to MarkusvonBroady and Blunder for the clear suggestions! That is exactly what I was hoping for by posting here!
Chris: Thank you for the suggestion to look up Erindale and Johnny Matthews for geometry node tutorials. I will definately check them out!


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Screenspace Reflections viewport VS render
I get two different results for the screenspace reflections. Behind the "moon" I have set up a dark background plane.

In the viewport it gets reflected and makes the marked area darker.
In the final render the HDRI background image takes over and cancels that dark area out.

I tried a reflection probe, that that cancels out the HDRI reflections. Does anybody know how I can get the viewport result in the final render?
Thanks in advance

Probably better to share your simplified file via https://blend-exchange.com


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Aligning instances to normal + facing forward with geometry nodes
I have a leather strap mesh that's deformed with two curve modifiers (Curve A for the strap wrapping around a hook, and Curve B for the general shape on a body).
I instance a top stitch mesh on certain vertices which are part of a vertex group. By using the setup below, the instances are aligned to the normals properly, however, they are not "facing forward" as you can see on the left end where the mesh wraps around.
I figured I could use the tangents of curve A to align the instances in the forward direction. It seems to work, but I cannot figure out how I would set the factor for each instance.

If I get rid of the Curve B modifier and just have the mesh follow Curve A in a straight fashion, everything works. But as soon as I throw a 2nd curve modifier in the mix that alters the general orientation of the mesh, it breaks.

Using a "realize instances" node at the end of my setup and placing the 2nd curve modifier (Curve.001) below the geometry nodes modifier solves my problem. I was hoping to avoid this for performance reasons, so if anyone knows of a better way to achieve this, I'd appreciate some feedback.

Realizing the instances and placing the 2nd curve modifier below the geometry nodes solved the problem.


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distance to object as single value per instance
I have an array of lights and want a wave to run across it. Each light should only show one value.
Using the distance method below, I end up with a smooth gradient.
Is there any smart way of achieving this effect with just a single value per light, and not a gradient?

I solved it by updating to a Blender Version above 3.1 and using a capture attribute node with the domain set to instance.

If anyone has a solution for Blender 3.0, I'd love to hear it.

Why are you using 3.0? Update to 3.3 which is the LTS version.

Because it means fixing some shaders, which I wasn't prepared to do.


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Why do I have Lines on My hair and How do I remove it
I have this baby head on which I made hair I used the Particle Edit Comb Brush. Why do I see these horizontal lines and how to remove them
Thankyou

what horitzontal lines do you mean? and please provide your blend file

The mentioned lines are the six horizontal lines created by vertical "gaps". It's on the left side of the head at the level of the ears, where the strands are disconnected (or end?). I'm not sure if it's an optical illusion. The hair seems to be very close to the head. Maybe puff it a little?


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Transparent background render taking ages
I am rendering a animation, I originally had a white background but that was taking forever, so I turned on transparent background.
The issue still persists, Blender wants to render the scene, each portion of the render fly's through, but 1 full transparent frame takes 25 seconds.
Is there a way I can tell blender to not care about transparent portions.

The animation is a phone coming up and rotating.

Hello :). Simply enable Adaptive sampling. Transparent areas are then rendered with 1 sample only.

@Emir That forum is very helpful thanks

@JachymMichal ah thanks ^^ didnt see that.


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Why isn't my project rendering anything? It just shows a checked pattern
I've been working on this project for a few weeks and the rendering has been working fine up until now. The render preview is working, as you can see in the screenshot at the top of the attached image, but when I hit fnF12 to render, it just shows the checked box pattern and doesn't do anything, as you can see in the screenshot at the bottom of the attached image. Why has it stopped working suddenly and what can I do? I tried opening up another project and rendered the default cube, and it worked fine, so the issue must be specific to this project. Any help much appreciated, I'm pretty much a beginner at Blender. Thank you!

Look carefully when you go to render. Are there any banners or messages that pop up, warning you of any errors? It may be that you hit the limit for your computer's memory. Try switching to CPU render.


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I want one controller to affect the whole Rig
I have created a rig that moves all the desired parts but I need one main control to affect everything at once such that individual controls rotate around allowed axis when that main control is moved


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How to create a hole in a rotated face and choose the distance between the external and internal edge?

I want to create a square hole in a wall, but I would like the space between the external and internal edges to have a specific measurement (0.005 m). I succeeded to do it on one wall because it is aligned with Global Orientation, but the wall where I want to create the hole is rotated, making it much more challenging for me as a beginner.

https://blender.stackexchange.com/questions/52308/how-to-extrude-and-scale-with-an-even-offset https://blender.stackexchange.com/questions/50876/how-do-i-inset-a-face-equally https://blender.stackexchange.com/questions/1088/is-there-a-way-to-offset-an-edge-extrude-edge-loop-perpendicular-to-each-edge/ https://blender.stackexchange.com/questions/14868/inset-in-blender-not-coming-out-even/


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Is there a way to change the modifier orientation?
Well, in this case the modifier is the "Array" and I would like the measurement of the "Constant Offset" of the Y axis to correspond to the Y axis of the "Transform Orientation".
I don't know if there's an easier way to do what I want, but what I thought led me to this idea, but I don't know if it's possible.

To answer the question you asked, no. The transform orientation is entirely contextual (currently it is set to “Face”), while modifiers must continue to work no matter what the context is. They are applied on top of all other operations procedurally. You can use the object’s local axes, or the scene’s global axes, but not the currently selected face’s axes as that will change the moment you select a new face.
I suggest you ask the broader question of how best to achieve a certain modeling structure. You seem to have made a few wrong assumptions and hit a dead end when there was a path forward further back.


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A piece of fabric 2D to mesh 3D
I have a piece of fabric with a specific silhouette shape, envision its UV map in 2D view. I would like to animate the fabric to sew and wrap it around the body with a specific movement. I want to connect specific stitching points from the open fabric to the sewn garment. I would like to understand if I can make the Hook, Sewing, and Follow Path tools interact. I have the 3D model of the fabric in CLO3D, both in its sewn and extended versions. The traditional sewing method typically works with two fabric pieces, side A and side B, but I only have a single piece of fabric.

Welcome! Just a quick question to help us narrow down the issue, what have you tried so far? This site is usually for if you’ve tried one thing or another and have found an issue with it rather than asking for how to do x y or z. Please elaborate on what you’ve tried so far and what luck you’ve had. Cheers :)

A sketch or screenshot would also help. How complex is the model and the fabric that you want to wrap around the model? The short answer to your question is: yes, you can use hooks, pin groups, sewing, shape keys, force fields and even an armature to control and influence a cloth simulation. If the fabric mesh is too heavy (geometry-wise) you also can use a low-poly proxy model and bind the fabric with a Mesh/Surface Deform modifier.


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Has "Show pose markers" option been deleted in blender 4.0?
I am trying to add Action-specific markers in blender 4.0...
By googling I found this thread
Are animation markers part of the timeline or part of an action?, but couldn't find the option when I tried to check the "show pose markers" checkbox myself.
If it is no longer there, is there any equivalent of pose markers(markers specific to actions)?

This is the Blender 4 manual section on Pose Markers. (I've never had occasion to use them myself.)


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Installing brushes in Blender 3.0
I am very new to blender.  I downloaded some brushed from Poliigon and have now idea how to install them.

Any help would be appreciated.
Thanks in advance
Dave

Poliigon has a tutorial on Using Brushes (in Blender)
It says, in part:

Enter into Sculpt mode

In the toolbar (T), Add a New Texture

In the texture properties, click Open Image

Locate your alpha brush and click Open.

In the toolbar, change the stroke method to Anchored

Click and drag the brush onto your mesh, and you should see the folds appear.

EDIT:  3.0 differs starting at step 2.  Here are the changes:

In the properties editor go to the Texture tab, make sure Brush is selected an click New
(Optional) Give the texture a name
In the Image panel Settings subpanel, click open.
Find the image by navigating the file panel.
The texture should no be visible in the Tool tab of the sidebar. (Not toolbar.  Use N to toggle sidebar visibility.)
To save the brush, click the "Fake User" Shield.
Change the Stroke Method to anchored.

Thanks for your quick response. Version 3.0 is different than the video.  I think I did it correctly but still having trouble applying it.  I didn't see any way to save the brush. I will have to play around some more and see if I can get it working.


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Lighting with draw mode
How can I brighten my work with Drawing Mode? Except with the Light I show in the 2nd photo.

Do I have a chance to illuminate the drawn with Draw Mode like Bezier?

If you want your GP object not affected by light disable Use Lights on every GP layer:

If you want white color to be exactly white, I think it is better to disable color management. To do this, set View transform to "Standard":

do we have a chance to increase this light?

I do not understand. Disabling lights makes it shadless, so that initial color is shown, without shadows darkened the colors.

On the contrary, can I increase the brightness of the light?

Check my update in the post

Thanks, my problems are solved.
I will ask one more thing. Can I add emission to the line drawn with Draw Mode?

I think not, but where some effects in GP, like glow, are available. In this site, better ask one question per tread, so that others can have a chance to answer.

Thank you for your comment, I solved all the problems.


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objects disappear
When it moves away from large objects, it disappears into the darkness. How can I set the visible distance of objects?

Hello, in the N panel > View tab, check the Clip End value

You might want to adjust the view clipping limits of the 3D viewport, these settings are available in the right-hand side menu (toggle its visibility with keyboard shortcut n).


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Weird Clipping when Shading Smooth?
I'm still quite new to Blender, but I was trying my hand at making a head for the first time. I normally sculpt it from a rounded cube, but I decided to try something different this time. All was normal until I chose to "Shade Smooth," then this unusual seam appeared around the jawline and back of the head. I managed to fix part of it by recreating the edges, but that did not work on the rest of it. What happened and what should I do?

it can be inverted normals, or inner faces, or overlapping vertices

Any idea how I should go about fixing it? My mesh in the wireframe looks clear with no overlaps or anything and I've tried reconfiguring the vertices, but it continues to look like that when I feel them back in.

Rather than going by look, in edit mode, select all and use the M key to bring up the merge menu.  Select "merge by distance". If there are overlapping vertices this will find them.  Then deselect all, go to the select menu, Select All by Trait submenu and select Interior faces. If there are interior faces they'll be selected and you can delete them.

Please share your file

Thank you for your suggestions, Marty. However, merging by distance did not seem to do anything to my mesh (I even switched off the modifiers to make sure), and no faces were selected when searching for interior faces. Moonboots, how should I go about sharing my file?

Have you tried recalculating the normals?

I just did, and it worked! Thank you all for your suggestions!


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Making Straw in Blender
I need to recreate this product and am not sure on how to model the straw inside the box.
Any ideas?

Hi :). What have you tried so far and where exactly are you stick?

Is this question about ideas or about how to use hair particles? (see question tags).
You can make straw really easy with hair particles.
Another idea is to use cloth simulation with a few obstacles.

Ultimately we went without the straw, but I think it's an interesting problem to solve regardless.
In my limited experience with hair particles, making something this chaotic just felt unachievable, but like I said, my experience in that area is very limited.
I considered making the straw using splines and just getting my hands dirty making it all manually, but I felt like there must be an easier way. Appreciate you guys taking the time to look at my question, sorry for not being clearer!


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My render shows the grease pencil on the front and backside of my 3d object (x rays right through the 3d object
Why do my lines show through from the back of the object? I delete the default cube; add a sphere; add a grease pencil; go into draw mode; press 1 for front mode; get the ink pen; push the strength to 1; write on the front face and go around to the back of the sphere and write on it.

Had this problem for a few days as well, finally got it to work by checking the "z" checkbox under Data under Passes in view layer properties. Heres the reddit thread i found the answer in if this doesnt work or you need additional info. Hope this helps :)

Thanks!  It worked.

This wasn't working for me in 3.60.  Instead, I found this:
N Panel: Annotations   (mine is pinned, it might be under Item tab?)
There are two icons for each layer: overlapping squares, and eye.
Click the overlapping squares so the front square becomes opaque.


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How to split surfaces
I wish to create an edge by extruding a vertex and thereby splitting a surface in Blender 3.2.
Entered edit mode

Selected a vertex in vertex mode.

Extruded the vertex with the y constraint.

Surface does not split as expected.

I can't find the CG Essentials tutorial on how to do this. I did get it to work once, but I don't seem to be able to repeat it.
Any help would be greatly appreciated.

I think what you want is the knife tool.

Or, subdivide an edge and G + G vertex slide to get it in place, and then connect the two vertices with J to split a face

Is this the CG Essentials tutorial you were referring to?
https://www.youtube.com/watch?v=gt-E2kPs2hY

That's exactly it thanks curious_1 and thanks Allen Simpson for your help. That's working now. Although I'm playing with splines instead of loopcuts. So I actually won't need the subdivision modier. But it's good to know thanks.


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Can application templates be used to modify splash screen only?
I'm trying to modify only the splash screen via app templates, while maintaining the users prefs and startup for each user (studio environment). The documentation makes it seem possible as mentioned here:
"Template Contents

Each of the following files can be used for application templates but are optional.

startup.blend
Factory startup file to use for this template.

userpref.blend
Factory preferences file to use for this template. When omitted preferences are shared with the default Blender configuration.

(As noted previously, this is only used for a subset of preferences).

splash.png
Splash screen to override Blender’s default artwork (not including header text). Note, this image must be a 1000x500 image.

__init__.py
A Python script which must contain register and unregister functions."

In my case I was only supplying a splash.png and assuming it would pull from the users userprefs for everything else that is not supplied, however for everything else it seems to default to factory defaults. Its important to maintain each users preferences in this case as this is being distributed in a large studio environment. What would be my options here?


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Using a texture with the wave modifier to highlight crests
I'm wanting to apply a gradient texture to an object that is using the wave modifier, in a way that only the wave crests, or a z-range, get a color ramp band. It doesn't work with the wave modifier active, but it does work with the modifier applied, so the texture coordinates seem to apply only to the original (non-modifier-ed) mesh, which probably makes perfect sense. Unfortunately, the mesh is then static. The intent is to have a dynamic python-generated driver initiate the 'ripple' via midi input, so static or pre-rendered isn't in the cards.
I've added an image of the very simple node network and one of how I'd like the effect to look, but the image is of the mesh with the modifier applied, not active.
Is there a way to get a texture to do this while the modifier is active? I've seen a way to do something similar posted here using material displacement, but the wave modifier has some nice controls, so I'm just wondering if there's a way to do it with the wave modifier, or is that just too lazy. Thanks for taking a look.

please try the same setup without applied modifier and use uv or object coordinates. That should work. If not, pls provide blend file. thx.

Just to document your guess and Chris comment: from the Texture Coordinate Node documentation, "Generated" coordinates are based on "the mesh without deformation".

As Chris suggested, just switching the texture output node from 'generated' to 'object' did the trick. Perfect! Thanks so much. Also, thanks to StefLAncien for the reminder to rtfm along with the specific pointer. TIL. Here's a still from a dynamic animated wave-ripple with modifier active, not applied.

Blend file here:

P.S. - @RobinBetts 's comment suggesting how to highlight only the wave crests and not the ground plane sent me off on a learning experience, which resulted in a working version of this, doing what I set out for it to do in the first place. It's an extension of my original question, so if adding this to the original post is out of bounds, please let me know. Just thought it might be useful for anyone in the future trying the same thing.
Thanks for the suggestions, they were all helpful!

Final blend file:

You might also want to explore using (Normal Z component) to catch the peaks of the waves, irrespective of their height. Then your ripples could decay with distance, if you wanted, without losing the shading.

You read my mind - that's exactly my end goal, but was very glad to at least find out this direction wasn't a dead-end. I supposed some masking (or map range?) will be needed, since the outer edge of the falloff would also be undesirably included in the normal z component, but I think I can manage that.

you could AND (multiply) the Normal Z with (Generated Z Greater Than tiny) to mask out zero-height water. Negative heights would just be some offset, depending on what space you're using. Personally. I think I would use Object Space, to keep 0 at flat-height.

Your suggestion makes perfect sense, in that I get how multiplying works like an AND with the ground plane, but I have some experimenting/reading to do here to figure out how to actually implement that in nodes. You've set me on the right path - thanks Robin.

I updated the answer with an addition of a working version based on @RobinBetts 's suggestion. Thanks to everyone who helped get me past my brain-freeze.

Very nice!  More sophisticated than my little mini-trial before passing comment :) Shame I can't upvote twice.


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I have these weird dark smears on my model when set to smooth shading

I have a weird effect on my model for this retopology im doing for a character. It looks like someone smudges some black along some vertices and I can't fix it and don't want to use the auto smooth shading option (which seems to get rid of it for some reason).

Is is something with my vertice or edge positioning? I can't find anyone with the same problem.

Could you check if you have duplicate vertices/edges, then merge by distance ? It seems that the normals are discontiguous along the "vertical central line" in your picture.

Also make sure that you don't have inverted normals, select all and press Shift N to recalculate, if it still doesn't work please share this part of your object


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Why does the Rasteriser take up so much frame time?
Having just downloaded the BGE, I have set up a simple scene with a rigid body cube and a plane, they both interact as expected, but when measuring frametime I register stable 45 FPS, as per in the image. The Rasterizer takes up 94% of all the frametime, lasting over 20ms. This doesn't happen in other softwares. Why is it happening? I tried using the Viewport Renderer and it works perfectly fast. I have uploaded the scene onto a link for sharing: https://easyupload.io/c6x94s. If you can help it'd be greatly appreciated. Here's a screenshot too: https://imgur.com/a/P8QEhmR.

Try tagging your question 'upbge'. - The game engine was removed from Blender with version 2.8 and is maintained seperately nowadays.

Hello and welcome. While files, images, and external videos or links may be helpful additions they should not be the only way to obtain information about your issue. Don't make understanding your question rely on downloading a file, watching a video or visiting an external site. Use the builtin tools to upload images or gifs, along with thoroughly explaining the problem in written form so it can be indexed and searched for thus helping future visitors with similar issues.


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How can I unhide objects? All the objects are shown in the layer tab
How can I unhide objects? All the objects are shown in the layer tab

Only one object is shown. but I'm sure I didn't hide any other object.

You must have pressed / which switch your view to Local (it isolates the selected object(s)).
To exit Local view, press / again

Yes, thanks, I've edited  ;)


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How do I move eyes with a body?
I have a spider and I animated it, the issue, when it moves, the eyes don't really follow and just move around which gives a stupid look to the spider.
Is there an easy fix for that? The eyes and the body are joined

Hello please share your file so that we understand what's wrong?

Not enough details! You say that the eyes are joined to the body. Are they now part of the same mesh and did you join them before you started animating? If you joined them after you parented the armature you may need to weight paint them to follow the rest of the rig. As @moonboots says we'll need to see your Blend file. https://blend-exchange.com/

Hello, I published an updated version, can you check it out and tell me if you understand? Thank you very much


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Hair particles render a lot differently then in the render preview
I set Hair Number 6000 and the Children Render Amount 500, but the hair in the render view port is much less than it suppose to be.
Blender project file
In the solid mode the amount of hair looks right

In the render preview the hair is much less

The Display Amount control (Particle System > Children) affects how many hair instances are visible in the 3D viewport regardless of which mode the viewport is in, so even though you do have the children Render Amount set to 500, you currently have it set so that only 50 of them will appear in the viewport. When you increase Display Amount to 500, all of the child hair instances will render in the viewport and it will look more like what you are expecting (see below).
However, rendering all children (especially 500 per each of 6,000 hairs for 3,000,000 total) will severely impact performance, so it's probably best that you leave the Display Amount substantially smaller than the render value (around 50 is what you had it at previously).
Leaving it at this value does not affect what the actual render output will look like, since at that point Blender will render all of the hairs. The image below is the render result with the settings exactly how you had them before (Display Amount = 50, Render Amount = 500), and it looks like what you're expecting.

I see, thank you so much for detailed explanation!


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How can I render this procedural material and mesh at the same time into a single image?
I am just trying to find out how I would go about rendering this mesh with the procedurally generated material on it into a .PNG with an alpha channel to use for some artwork.
Mesh With Material On It

Node Layout

So after almost an hour of tinkering trying to find the answer, it turns out that I had the Material Data linked to my mesh, but not the Material Object linked. Linking the Material Object solved the issue. Screenshots below for those who are suffering the same brain fart lol.

When you first click on the materials tab on the right hand side you will see a upside down triangle with points where the square with four corner outlines is currently. Change from the Data option to the Object option then click on the circle to the left of the material name with the drop down icon. Under that drop down select your material and presto your Object Data will be linked, allowing for cycles rendering of your material.


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How do I look top down in blender, but at a different orientation?
I was wanting to look top down at my scene, which I do by clicking on the Blue Z in the top right corner. However, when I click that Z, no matter which way I was facing, I am always looking with the positive Y in front and the positive X on the right, is there any way that I can look top down but at a different angle?

you can make the view rotate with 4 and 6 but I guess this is not what you want

Yes, I am aware that I can look side on from different angles, but I want to be able to look top down from different angles

Do you mean the orthographic <-> perspective view? Use Numpad_7 for top view and then you can toggle the view with Numpad_5 (or click the grid icon below the camera icon and the gizmo (XYZ control))

I think he means he wants to rotate the orthographic view in 2D. Like rotating the canvas.

If you mean you want to roll the camera, this answer will probably help. The suggested key-bindings still work in 3.0


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How do I move objects randomly on a single axis with geometry nodes?
I am trying to make a wall with lego bricks, and I am trying to move each one slightly differently on the Y axis so it looks more realistic. However, I am lost as to how you can do this. Here is a screenshot of my current node set up:

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.

you can do it like this (so you were pretty close). Geometry nodes is a bit confusing at the beginning, but the longer you are doing it there quicker you will get ;)

sorry, i thought you meant rotation. Here the node setup for the movement:


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How can I have an object follow a bone but retain its transforms
I have a skateboarding animation from Mixamo and I'm trying to attach the skateboard to the foot that isn't pushing.
When I Parent the skateboard to the foot bone it works but there is a small rotation in the foot during the animation that is translating to the skateboard and it is clipping through the surface.
What I want is to move the skateboard as though it's stuck to the foot but keep its original translation.
Hope someone can help

Try to use copy location constraint

Thanks! I had been trying to keyframe it but it's time consuming and the results aren't great


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Animate along a path while path is parented to camera rotation
I'm creating a short anim loop of the trench run in Star Wars. I have the camera keframed with some rotation and location data (position in the cockpit chasing rebel X-Wing)
I want to shoot the lasers and had an idea to use a follow path instruction where the Path is parented to the camera.
But it seems I cant keyframe when the path should start.(for example, shoot lasers on frame 18-22)
When I try I get this message.
It seems like there is a clash between the Location/Rotation data from the camera and the path following data. Is there a way to get these to work together or even a better way of achieving what I want?
Thanks

OK I've found out that the particle system is a better way to achieve this. I have some problems with that too but I'll start another thread for that issue. Thanks

You don't want to animate a path follow that way anyway.  See this answer for how to use the curve's evaluation time instead.  But using the approach from that answer you can definitely do the relevant animation directly.


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Is there a way to join the roots of bones?
I'm learning armatures and trying to rig a model with a basic rig by extruding bones.
I think I made a mistake however as the legs are separate from the body.
Is there a way to join the roots back together or do I have to redo that part of the rig?
I've already parented the mesh parts to the bones so I'd prefer not to start again.

Joining the roots is not allowed, you can parent them to the same bone so that roots will be joined.

Select the armature, go to edit mode, select the child bones, shift select the parent bone and press Ctrl P (keep offset, if it's not a connected chain).
Generally legs are child of the Hip bone.
Mesh binding will not be affected by the operation.

Thanks mate, I'll give that a try


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Collection Instancing: Origin point
I'm following a kitbash3D tutorial on instancing groups of buildings.
When I make a new collection and instance to scene, the origin point is offset. This is making it difficult to move and rotate the instance properly. It seems impossible to move the origin after instancing.
Is there a way to keep the origin at the centre where it should be?

You can also try this https://blender.stackexchange.com/a/164070/86891

You just need to right click on the instance and > Set Origin > Origin to Geometry (or to 3D cursor). Or open the original collection, move the objects. The instance empty, which will be the instance origin, will be placed where the scene center is relatively to the original objects.


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Metaballs: Material duplicating issue
I'm using metaballs to make a cheap fluid like flow effect using the particle emitter. I am using a curve as a guide for force.
I also have another smaller version of the same thing in the scene, and would like to use a different material for that metaball.
However, if I spawn another metaball it instantly takes the material of the first metaball and is unable to be changed.
These fluids won't interact as the curves are separated.
Thanks

Use a texture that has an object defining it's coordinates. You can use as many colors as you want in the colorramp. You could also do something nifty with shaders where you use the colorramp to be the factor in a mix shader. Or you could use a noisy gradient if you wanted, as shown.
Look at the node setup.

Thanks thats helpful, I guess all metaballs in the scene are linked. I was hoping there was a way to have separate groups or collections or something.

I agree. There should be an option where metaballs could ignore the ones not in their 'group', or something to that effect. This solution would get tricky if you were not in the same plane.


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Cable rigging for robot
Basically I want to a cable attached to a 6 axis robot which goes from axis 3-6 or whatever. I've done this fine with a Nurbs curve and hooks etc and it works great, follows the robots movement and everything. The only problem is the stretching, the real cable does not stretch but if I turn off stretching it comes away from the end of the robot.
Is it possible to have stretching off but maintain all hook points? So the slack goes else where like in the centre of the curve and not over the end?

If the cable can't stretch, but needs to stay connected on both ends... Then have you tried making the cable longer? Cause when you say "Have the slack go elsewhere, like in the center of the curve" that's like the dictionary definition of stretching.

Making it longer just pushes more cable out the end. This problem really isn't simple and ive tried so many options, and the 'slack going else where' is not stretching at all, its the slack produced when the length from a to b gets smaller. This happens when i move the robots IK solver target.


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Weight paint blur and smear can only draw at full strength. How do I fix it?
I am trying to weight paint my model but when I go to blur and smear the brush just continues to add weight like it is drawing with full strength/turning everything red. Turning down the strength doesn't work. It was working before but after I went to check my rig it no longer works. How can I fix it?

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.

When I use the blur tool it would gradually spread out the weight around the vertex and the smear tool would push the different weights to other vertices. Now when I use the tool it would just paint the vertices red like I was drawing with full strength on if that makes sense.

hello could you please share your object, at least a small part, so that we can try?


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translucent white resin with embeddings - material
I need to make a volumetric translucent material, possibly working in EEVEE.
It is a white semi-translucent resin with objects embedded.
The embedded objects are more visible near to the surface of the resin, as you can see in the reference image.
now, the transmission parameter in eevee does a pretty good work at gradually blurring the objects behind (or inside) a transmissive surface.
what i'd need is that the more the rear object blurs, the more it goes less visible, taking the base color of the transmissive surface.
Any ideas?
Thanks

Hello, you could also plug a Principled Volume into the Volume input of the Output, but in Eevee it won't be as good as in Cycles

https://blender.stackexchange.com/questions/303262/procedural-recycled-plastic-material/303266#303266


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How to Animate object along its Local axis?
I want cut these wooden sticks with wood cutter saw but I don't know how to animate saw along its local rotation.
I mean , I want saw remain tilt and spin tilt. please guide me how to do so.

Hello, this looks as if it has been effectively answered here: https://blender.stackexchange.com/a/129836/35559 . Please let us know if this is a fix for you, and if not, why not, linking back to that post.


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Blender Stretching Bendy Bone Rig Issues
I started using Blender a few months ago and I am experiencing some issues.
So I built a bendy rubber like rig for my Lego character using stretch to. (Displayed in B-bones, you can see it in the image below)
But after parenting the figure's legs with the bones and trying to move them, the right leg somehow moves in a funky way and doesn't really follow my rig, while the left one moves normally. Their weights are the same.
Here are a few images.

A close up shot.

A side view of the rig.

Their weights are absolutely the same.

What should I do next or check to fix it? Please, can anybody who knows Blender help me? I have so many questions. :(

hello please share your file

This looks like your mesh is assigned to other bones than the ones you expect. Does this answer your question? Parenting Mesh to Bones Issue (see the weight paint section at the end of my answer).


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Weird behaviour: A simple material renders fine on one mesh but not the other
I have a weird issue with Cycles in Blender 2.92:
This comes from a larger project but I was able to reduce it down to this small example.
The triangle is copied from the project I had issues with and the plane is new, both use the same material, however they render differently:
Rendering result in Eevee

Rendering result in Cycles

As you can see at least in Eevee it produces a usable result but in Cycles the triangle is just black, the plane demonstrates that the material is not broken as it works fine there in both rendering engines, so the issue must be with the triangle mesh for some reason but everything I've checked (normals and such) seemed fine.
Here is the example file I made which displays this behaviour:

Any idea what I'm doing wrong?

There are Custom Split Normals on your triangle, set to (0,0,-1), by something. (An applied Edit Normal modifier?)
If there are shading anomalies, it's often worth checking what the renderer thinks the normals are, by displaying vertex-per-face normals in the Edit Mode 'Show Overlays' menu:

If you go to the triangle's Data tab > Geometry Data panel, you can clear those.

Incredible, that solved it. I would have never found this myself


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Problems keyframing a simple cube, End keyframe cancels the starting keyframe
https://photos.app.goo.gl/YvCDueDAgrZonAcE7
Hopefully you guys are able to see that link above. However, let me try to explain the issue:
I am trying to animate a basic cube. However, I only want to animate one face of the cube and leave the rest intact with the same location and scale.
I am able to insert the first keyframe (frame 0) but when I try insert the second keyframe (frame 60) it seems to "cancel the first keyframe and makes them both look the same, which obviously results in no animation.
Any idea how to keep the first frame the way it is when add the second keyframe?
PS.: shape keys are not possible here because in the actual video I would have multiple movements, so I would need many shape keys.

This kind of animation is - AFAIK - only possible with shape keys.
And as you can see - you can only add a keyframe to location (not to vertices or frame) and just in object mode. So the animation frame does relate to the whole object and it's location. Not to vertices or faces or edges.

"only possible with shape keys" - https://blender.stackexchange.com/questions/9355/is-it-possible-to-animate-a-meshs-geometry-without-using-shape-keys

HI Chris, thanks for the reply.
The problem in my case is that I would need 3 or 4 shape key values to make my actual animation work given how my character moves, and as far as I know we can only have 2 shape key values, no?

you can have as many shape keys as you want - AFAIK - just the memory of your computer is your limit ;)

To do exactly what you want, without shape keys, you will need to enable the AnimAll addon by going to User Preferences, then highlighting the Addon category, then typing "AnimAll" in the search field to make it pop up in the list, then checking the box beside its listing to enable the addon. Now you can keyframe vertices in Edit Mode in the same way that you would normally keyframe primitives in Object Mode. However, standard shortcut keys do not seem to create keyframes. You may find that you need to set them by clicking with the mouse in the included AnimAll UI, which can be expanded by clicking on its associated tab the Properties Shelf (press n to bring up the Shelf). The properties shelf tabs appear immeditaely to the right of your main 3D view, but still left of the Properties Panel. I also found that while the keyframes are SET in Edit Mode, their effects cannot be displayed until manually scrubbing the timeline in Object Mode.


text:
Building is half "Reflective"
I am hoping some of you clever people can help! I am a complete novice at Blender but It's been fun and frustrating learning it!
Anyway I have made a few buildings for my local Airport for MSFS and one building is sort of half reflective like a mirror this is the only building I have had bother with (used same settings as the rest of the others and specular is turned down) and I just can't suss it out.
In blender and ModelconvertorX it looks fine.
Any help is appreciated.

It appears to actually not be reflective, but just transparent. Is it possible that a texture somewhere is being mapped onto the wrong material? Double check all your blender materials and see that nothing is connected to any kind of transparency setting on the shader. In EEVEE, materials will render opaque unless you have their blend setting changed to something else, even if something is connected to the transparency of the shader. I’m thinking that something is connected erroneously, but it’s not showing up in blender because the blend setting of the material is set to the default “opaque.”

Thanks for the reply. As I say I am an a novice at this and tried your advice and I am probably doing it wrong but I am stumped!


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Why is it when I render I Get a blank grey screen
I've been having this problem, and I don't know why. ill just give some context. I had imported this model from SketchUp, along with the camera view from there. It was working fine, until I decided to delete the SketchUp cam, and decided to add a new one. I've been having problems since I added the new cam. The model is just fine, and so are the materials, When I put the viewport shading into any mode the model looks fine, however when I decide to render all I get is a grey screen when it finishes rendering. I'm using the cycles render engine. I have read all of the other forums that are similar to mine. I have checked that its not an issue of clipping, or depth of field, or that it is a material problem. I just seem to be stuck. Would be great if someone can shed some light on what I'm doing wrong
Many thanks in advance

provide your blend file

We'll need some details to solve your issue.  A screenshot of the gray screen (there are a couple different things that could be described as a "gray screen") and the viewport render are a good way to start.

Maybe it's a hardware problem like in this post, we had a lot of those questions here:
https://blender.stackexchange.com/questions/204297/amd-gpu-material-in-material-preview-mode-and-rendered-mode-is-entirely-gra

The new camera you added may somehow be set as an inactive camera. This is the case if the triangle over the camera is an outline and not solid. Select the camera, go to the view menu, go to cameras, and click “set active object as camera.“


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Texture Paint Not Updating Automatically
I am texture painting over a 3d Model. When I fist began this process, I could paint in the material view, then click over to render view to see how everything was looking with cycles. Now ever since I saved the texture paint image file (to make sure I don't loose my progress) the painting does not show up automatically when I switch to cycles render view. I can still see the paint as I am painting in Material view, but when I tab over to render view it is not there, until I go over to my image editor and manually save the image texture again. It used to update automatically. Now I have to manually save the texture every time I want to check out my progress in rendered view. Not a huge deal but very annoying. Any ideas?
Blender version 4.02

I think that the image texture doesn't refresh instantly in Rendered preview in Cycles, you need to switch to Material preview then switch back

Unfortunately that doesn't work.

I did some more searching and this seems to be a known bug with blender. Hopefully it gets fixed, but its been going on for years apparently.


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Can Blender smartly split Objects?
I have a model of a motorcycle in Blender. This model is split into a few seperate textures/materials such as livery and mechanics. The problem is, that I want to split these materials as for example the exhaust is in the same texture/material as the forks but in real life the exhaust is rough metal while the forks are shiny, but I can only choose one appearance for all of these parts right now. Can Blender split the material into different by itself?

do you know that you can do face selection and select a material and then just click on "assign" to change the material just for that selected faces?


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What are clearcoat and ao masks? How do I use them?
I have got some clearcoat and ao mask files for a 3d model. What are those and how do i use them?

Is it an AO mask, or is it an AO map?  The first would prevent calculated AO from affecting the model.  The second would create AO, for a shading environment that didn't calculate AO.  The only way to use an AO map or mask in Blender is with a Specular BSDF, usable only in Eevee.  It might be useful to see what you are doing with the material so far, and in which engine.

the first is an ao mask the other is a so called clearcoat mask. I am using cycles

Cycles doesn't have any AO, because it doesn't have ambient lighting, and use of any kind of AO map in it doesn't make sense.  Clearcoat mask, just plug into the coat/weight input for a Principled.  Although your clearcoat mask looks like it's probably more than one map, and the clearcoat mask is one channel (RGB) of the entire image.  Maybe red or blue.

For the AO texture:
As @Nathan already said, AO (ambient occlusion) is not really a thing in Cycles since there is no ambient lighting, however there is a node for it in the Shader Editor to calculate AO which you can use in Cycles.
AO is calculating how much ambient light reaches surfaces, which is usually less in areas that are close to something occluding them partially so the surface areas are darker there. Typically AO gives darker values in corners or inside a mesh or where two meshes meet etc.
While this is done in raytracing engines like Cycles automatically, people use the Ambient Occlusion node in materials for example to create darker parts on a mesh which - since they are more or less occluded - also can get darker through dust and dirt as it cumulates in those occluded parts.
Like in the example below, there is a simple blue material on the object. It has some sharper corners where the Ambient Occlusion node calculates a slight darkening. By the way, the AO output of the node always gives float values between 0 and 1. For darkening the corners, people often use a Color Mix node set to Multiply or Darken with their base color (of course it can be an image texture etc. as well) in the input A and the AO in the input B. However for this simple darkening the Ambient Occlusion node has its own Color setting and the Color output. If I choose my base color there (or plug something in there) and use the Color output of the node, the result is the same as multiplying in the Mix Color node.

A slightly different approach I use in the next example, I'm trying to make some kind of khaki/greyish dust in the corners which should not simply darken the color. Mix Color node leaves a lot of ways how to blend colors A and B together, in my case I just use Mix mode and make A the dust color and B the base color. The AO output I use as mix factor. Since the corners are darker in the AO values, they will show the first color and the rest shows the second, the base color.

Since I do not know the mesh of your model and how it should look like, it is up to you how to use the AO map. It looks definitely like being layed out for some UV map, so I would guess you have an image map for the base color which I would plug into A on a Mix Color node set to Multiply and the AO texture into B. Like this, only that you plug your color texture where my blue color is - and of course my object is not your mesh so the AO makes no sense:

For the Clearcoat texture:
What @Nathan said is mostly true, it seems that only one of the RGB channels is the clearcoat mask - but the others are probably no mask for anything. In this case it is the green channel which holds the mask information since it has a black (almost black with 0.004 or so) and white part, while the others are (apart from some JPG artifacts) completely white, so not really masking anything. This is the green channel, you can get it by plugging the texture into a Separate Color node and using the G output:

The Clearcoat or just Coat setting in the current version of the Principled BSDF is used to simulate when an object with a rough surface (and therefore not sharp glossy reflections) which you want to preserve gets added a top coat of glossy varnish upon it - but not necessarily glossy, therefore the clearcoat has its own Roughness channel in the Principled BSDF shader.
And now it depends on you again to know what this could be useful for since I do not know your model. Generally you can use this green channel to determine where an object should have a clearcoat layer (where it is white or 1) and where not (black or 0). Or this texture was made for a different working shader, and you need to invert the color to switch white and black and so the clearcoat/no clearcoat distribution.
To do this the usual way, leave the coat roughness at the default low value and plug the green channel (or the inverted version) into the Weight input under Coat in the Principled BSDF to mask where the clearcoat is:

You could also set the Weight to 1 to have a clearcoat overall, and then plug the green channel into the Roughness input in the Coat section. Although with black and white resulting in black being completely smooth and glossy and white being completely rough and not glossy at all, it will visually mostly appear as the example before with the Weight just being inverted.


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What is Map type "l"?
for a model of a motorcycle i have got multiple texture/map files for each part. For example for the brakes I have got these three

I know that the last one is a normal map but what is the second one? It has an "l" in the file name but I am not sure what this means

It is most likely an ID map, used in substance to be able to use smart materials

how do i use it?

Looks like 3 maps combined to RGB channels.
R:

G:

B:

Maybe bump, roughness and strength for glossy component(would be "IOR Level" in PrincipledBSDF)?

Just a guess.

I cant find IOR level

If you're using Blender version 4+ it's under the Specular dropdown on the latest Principled BSDF shader.

@Buzzer4246, yep, I assumed you are using current version of Blender because you didn't say otherwise. That's 4.0.2 at this time.

Yes. I updated Blender now it works. I always lose track of the current version


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X-ray mode stopped working in Material Preview in a specific file
I have a specific .blend file I'm working with where X-ray mode seems to no longer be working in Material Preview, in Edit Mode. When I turn it on, all it does is make the edges of the mesh kinda thick, but it doesn't show the faces and edges and vertices behind the current frontface. X-ray works fine in Solid mode, and in other files' Material Preview mode, but not this specific file.
Here's an example of a file where X-ray does work in Material Preview, versus the file that I'm having trouble with.

How did I break it? How do I fix it?


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Carve geometry according to alpha
The thing I want is to carve out pieces of a mesh based on an alpha texture. It's not a noise texture, it's a specific alpha texture I have that is UV mapped, and I want to delete the parts of the mesh that would otherwise be transparent (in this case, because I want to use this mesh somewhere that can't handle transparency well or at all). I've tried to look around for an answer to this and pretty much all of them seem to be from before Blender 3.0, which used to have the Attribute Sample Texture geometry node. How do I do this in current versions of blender?

You're always going to have sampling and topology issues with doing something like this, but understanding that, I'd do it something like this:

Starting with a plane, I subdivide it heavily, look up object coords on each face, and delete any where the alpha of my image texture is less than some threshold (here, 0.5.)
For mapping to something by UV, send UV as an input vector instead of position:

That does not seem to work: https://imgur.com/a/v6w5wwe, no matter the threshold I pick or whether I pick Face or Point or anything else in Separate Geometry or how much I subdivide

You're using UV.  You should probably use UV rather than position for the lookup.

How do I do that? I can't seem to find any primitives that map the texture by UV here but I may be overlooking it

@Red Added an edit.

Perfect, exactly what I wanted, thank you so much!


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Constrain a camera to an object while also aligning it perfectly to the center of the object (relative to the camera) even while using perspective
So, Im trying to constrain a camera to view an object perfectly in the center...
Ive set a constraint on my camera so that it uses "track to" to point at the center of my shape.
However, I noticed that even when I use an exact measurement on my cameras position to give it a perfect 45 degree diagonal angle towards my object (x5, y-5, z5 for example), its still not aligned perfectly
As you can see in the image below, the object isnt fully in the center, even though its at a perfect position and its being constrained to the object position

Is there a way to constrain it and align it perfectly to the center of the object even while using perspective view (So I can move the object and have it perfectly centered relative to the camera's picture)
Or this unrealistic?
Essentially, I want it to perfectly fit in the center of the camera, no matter where I move it.

You'll have to clarify what you mean by "perfectly in the center".  You say "As you can see in the image below, the object isnt fully in the center" but it looks centered to me.

He's not talking about the center of the object, but the overall outline of the object - so that in his image the space above the top corner is the same width as the space below the bottom corner.

Shift the camera.
Adjusting the shift setting of the camera, such that the camera aligned 2d bounding box of object is centered.

Result of running on default scene, then transforming and re running, there is no constraint pointing camera to origin of object, if so there would be less shift depending on origin point

Firstly as mentioned in question am assuming you have the camera set
up and pointing to the object of interest.
A couple of useful links in regard to this.
Add camera at random position through Python
Script to render one object from different angles

Have added an optional option to create an object that shows the 2d
bounding box of object of interest lying on the plane defined by the
origin point of object, and with a normal matching the camera
direction.  Uses the code from
Getting edges of the camera's view on the scene XY plane
set create_bbox2d = True to False (or delete code) to remove completely.

It appears by your angles and camera positions that you are after a
"perspective isometric" view
Setting up an isometric view

To shift the camera requires using the aspect ratio from render
settings
Set Render/Camera resolution to Render Border coordinates

Putting it together as a script.  Select the object of interest, with a camera set as scene camera and run script.
import bpy
from mathutils import Vector
from mathutils.geometry import intersect_line_plane as ilp
from bpy_extras.object_utils import world_to_camera_view as w2cv
import bmesh
import numpy as np

create_bbox2d = True

context = bpy.context
scene = context.scene
ob = context.object
me = ob.data
cam = scene.camera
mw = cam.matrix_world
o = mw.translation

plane_no = mw.to_3x3().col[2]
plane_co = ob.matrix_world.translation

camdata = cam.data
bm = bmesh.new()
bm.from_mesh(me)
bm.transform(ob.matrix_world)
u, v = np.array([w2cv(scene, cam, v.co).xy
        for v in bm.verts]).T

tr, br, bl, tl = [
mw @ f for f in camdata.view_frame(scene=scene)]
# offset vectors from bl.
# eg middle would be bl + 0.5 * (x + y)
x = tr - tl
y = tr - br
# roll around in CCW direction

bbox2d = (
        (u.min(), v.min()),
        (u.max(), v.min()),
        (u.max(), v.max()),
        (u.min(), v.max()),
        )

if create_bbox2d:
    coords = []
    for image_coord in map(Vector, bbox2d):
        cx, cy = image_coord
        # vector pointing from cam origin thru image point (PERSP)
        vec = (bl + (cx * x + cy * y)) - o

        pt = ilp(o, o +  vec, plane_co, plane_no, True)
        if pt:
            coords.append(pt)

    if coords:
        name = f"{cam.name}_ViewPlane"
        me = bpy.data.meshes.new(name)
        faces = [range(len(coords))] if len(coords) > 2 else []
        me.from_pydata(coords, [], faces)
        ob = bpy.data.objects.new(name, me)
        context.collection.objects.link(ob)
        ob.display_type = 'WIRE'
# shift the camera
aspect = (
        scene.render.resolution_x /
        scene.render.resolution_y
        )

# UV origin shift
(u.min(), v.min() / aspect)
# UV shift

#v /= aspect
# move to UV (0, 0)
cam.data.shift_x += u.min()
cam.data.shift_y += v.min() / aspect

cam.data.shift_x -= (1 - u.max() + u.min()) / 2
cam.data.shift_y -= (1 - v.max() + v.min()) / (2 * aspect)

Quad view after making gif above, all the notice all "frames" (last one active) are in the same plane, normal to cameras direction
To animate this would use a frame change handler.

I don’t believe that’s possible since its ‘viewing centre’ will change depending on the object’s orientation, distance and geometry - as well as the camera’s orientation and settings (eg, focal length). This is too variable and dependent on the viewpoint.
Your current setup is using the object’s origin as the “anchor” for the lock and that is the best you can do with constraints.
The only other option would be to render the view larger than you require and then trim it down in post-processing. eg, you could have a script that determines the bounds of the object in the view and then crop the image to be consistently spaced.


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Weight painting doesn't change the VertexGroups
I have a hand mesh and an armature with 24 bones. I have used automatic weighing but I didn't like the results so I used the weight paint to change the weights. Now, when I try to select the vertices in a vertex group, the selection only consists of old vertices Here are some screenshots.
Here is the weight I painted for vertex group 14.

Here is the vertex group selection. This area is the same as automatic weights for vertex group 14.

I have used the following code for selection:
bone = '14'
bpy.ops.object.mode_set(mode="EDIT")
bpy.ops.mesh.select_all(action="DESELECT")
bpy.ops.object.vertex_group_set_active(group = bone)
bpy.ops.object.vertex_group_select()

I want the vertex selection to be same as the weight painting.
Any help would be appreciated.

If you were changing weights (e.g subtracting from previous weight paint) it doesn't mean they were removed from group. Vertex can have 0 weight yet still be in the group. Viewport menu > Weights > Clear or Vertex Weight Edit modifier with certain threshold settings can avoid that.


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Automatic weights skips vertices
I have an object and I added bones to it. It looks like this

I used automatic weights option to calculate the weights. But some of the vertices are not given a weight. When I move the first bone in pose mode it looks like this

I have tried removing parent relationship, deleting vertex groups and recalculating weights but the result is the same. I have no idea what could have caused this or how to fix it. Adding those vertices with vertex paint is not something I want to do unless it is the only choice I have so I am asking for help.
Thanks in advance.

In edit mode, have you checked that the vertices in question are assigned to the correct vertex group?

@Blunder The said vertices are not in any vertex group

Ok, that's the reason why this area doesn't move. I guess there is something wrong with the mesh (duplicated vertices, intersecting mesh?) and it causes the Heat weighting: failed to find solution for one or more bones error. It cancels the weight paint calculation and can result in such a half-working rig. Can you repeat the step (With Automatic Weights) and check if there is a warning for a few seconds in the status bar as you can see here: https://i.sstatic.net/QOFup.gif ?

@Blunder I have checked the mesh for duplicate vertices and there are no duplicated vertices. Also the object consists of one mesh not more. I ran automatic weights again as you said after deleting vertex groups and no error message showed up.

darn, it was a good possible reason. Can you share the file?

@Blunder Sorry for the late answer. Here is the link to the file
https://drive.google.com/file/d/1a8nxWULueEQmDZVDH6VR6KjAKbYrt7jX/view?usp=sharing

Thanks for the file. That helped to track the error. The mesh of the leg has flipped normals. The whole mesh is basically inside out. You can check this with the Face Orientation overlay (https://blender.stackexchange.com/q/119408/107598).
That's the reason why the With Automatic Weights does not work. Go in Edit, select everything with key A, and then flip the normals Alt+N as described here: https://blender.stackexchange.com/a/167034/107598. (I will mark this question as duplicate)


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Dynamic Enum Property - Maximum Recursions Exceeded
Hello Blender/Python friends. I am having an issue I am hoping you can help me with.
I have a dynamic enum property that shows a dropdown with a list of current objects that fit certain criteria:
my_enum_dt_wall_items : bpy.props.EnumProperty(
    name = "dt_wall_items",
    description = "Wall Items",
    items = wall_items_func,
    default = None,
    update = wall_item_update_func
    )

I wrote this function to update the enum items:
def wall_items_func(self, context):

    items = []
    current_wall = bpy.data.scenes["Scene"].my_tool.my_enum_dt_wall_number

    for obj in bpy.data.objects[:]:

        if current_wall in obj.name_full:
            if len(obj.name_full) < 9:
                value = obj.name_full
                visible_name = obj.name_full.replace("dt_","").capitalize().replace("_"," ")
                final = (value, visible_name,"")
                items.append(final)
            elif "Window" in obj.name_full or "Door" in obj.name_full:
                if "boolean" not in obj.name_full:
                    value = obj.name_full
                    visible_name = obj.name_full[9:].replace("_"," ")
                    final = (value, visible_name,"")
                    items.append(final)

    item = ("NONE","None","")
    items.append(item)

    return items

When I import a new object (which changes the enum value to that item's name) I am getting the following error:
RecursionError: maximum recursion depth exceeded while calling a Python object
File "C:\Users\Tony\Documents\3D Printing\CharacterCreator\Base\UnlimitedTerrainCreator_v0-2.blend\Unlimited Terrain Creator", line 1128, in wall_items_func
WARN (bpy.rna): K:\BlenderGit\blender\source\blender\python\intern\bpy_rna.c:1457 pyrna_enum_to_py: current value '1' matches no enum in 'MySettings', '', 'my_enum_dt_wall_items'

It seems this function keeps recursively calling itself, and I'm not sure why. I do have an update function for this property as well, but that function isn't getting called (at least not multiple times).
Does anyone have an idea as to what could be causing this, or at least how to go about trouble-shooting it?
Thank you.

Hello, looks like the culprit is wall_item_update_func, is it trying to access the enum items ?

Same as last time, replace bpy.data.scenes["Scene"] by context.scene... I also would suggest replace bpy.data.objects[:]by context.scene.objects[:]: https://docs.blender.org/api/current/info_quickstart.html?highlight=context#context

@Gorgious That's what I thought too, but that function doesn't access the items. I tried getting rid of it just to see and still got the error

@brockmann  good suggestion, thanks. Unfortunately I'm still getting the same error


text:
Fast Polygonal Approximation of Terrains and Height Fields. blender-gis
Blender-GIS import georaster geotiff with regularized quads.
To have a good displacement where the slope changes it's necessary to use the "Dem Raw Data Build". But the results is very heavy for the memory when you must perform some modifier.
So I'm looking for another way to create a mesh from a geotiff.
I found "Fast Polygonal Approximation of Terrains and Height Fields", with this https://github.com/fogleman/hmm. Very good, but difficult to use, because the result loose the georeferenced data, and it has a varying displacement.
Maybe is possibile to simplify the RAW data DEM mesh after.
In this image in the left part the result of Blender-GIS, and in the right part the result of HMM utility, view from bottom

and this is the same object mesh but in orthographic view

Thank you and happy holidays wishes

what do you mean by "lose georreferenced data" and "varying displacement"?


text:
math angle degrees problem in geometry nodes
(and Merry Christmas wishes)
I don't understand the trigonometric function in geometry nodes.
I tried to translate an object by a 12° in y, so the translation of z must result as sine(12°)*y
I tried with radians. I tried with radians and "to degrees". I tried with gradient.
Nothing goes well

I found the solution: sine(slope)*y = sine(tan(angle))*y


text:
gis data export
I have finally decided to learn and use blender for some editing work on digital terrain models.
I have a doubt: can't the models I edit be exported in Qgis and Grassgis readable formats?
This is the format possible: geotiff, grid ascii esri, terra aster, for the raster; grib, netcdf, 2dm, 3di, h2i, esri tin, anuga, hec ras, selafin, tuflow, ugrid, xms tin mesh, stanford ply (this last runs, but without correct coordinates)


text:
clean-up a terrain mesh from dem (blender-gis) to extrude
I'm working with a terrain mesh from a geotiff based on gps survey.
The surface covered by the survey is irregular, so I create an irregular mask with GRASS.
I imported geotiff with Blender-Gis with success, but the object has 256 non-Manifold Edges and 1470 Non-Flat Faces.

I presumed that this causes the fact that I can't extrude the entire object's edge. I want to create a "solid" from the plane mesh, because it's necessary to modify it with boolean difference with a cast "swale" (sort of ditch) object.
I tried to clean-up with 3D-Print addon, but I didn't undestand because the result of deleting zero faces and loose geometry is some strange faces without any vertex and edge.

Thank you in advance, and excuse for the probably english mistakes

It's hard to understand what your problem is... but you can try (starting from the 2d surface) to merge by distance (edit mode, select all a and merge m by distance) before extruding, and you will have a good solid. The borders with weird faces are unfortunately the result of something you didn't explain well in your question.

I found a solution! In GRASS I used a region bigger than the raster layer, and I exported the geotiff with a value for nullvalue. In Blender-GIS I imported the geotiff as DEM mesh (not dispacement texture) with 1 step, to give a maximum resolution. The mesh resulted was with a concavity towards a plane of the value for nullvalue defined. So it is possible to create a plane of the same dimension of the region, at a z level less than value for nullvalue, and with boolean difference split the mesh at this plane. The result is a volume without manifold or non-flat faces!!! Yeahhhh


text:
When exporting object animation to FBX, final object is distorted and breaking mesh
I have created a blender animation project that consists of a 3d model with armature and a mesh cloak over the model. The model and the cloak have been parented with weights to the armature. When I preview the animation, it looks perfect (https://youtu.be/tQM2WS0a7eU) but after exporting into an FBX format, there is obvious displacement of cloak, distortion of model’s hands and shoulders and artifacting with the cloak during movement (https://youtu.be/XpxCQ2sIGFQ).
I have been beating my head against the wall for days trying to figure this out so any help would be very much appreciated.


text:
Blender doesn't startup
I use Linux Mint 18.3, I updated my system, then, when I startup Blender it crashed. This is the error:
# Blender 2.79 (sub 0), Unknown revision

# backtrace
/usr/lib/blender/blender(BLI_system_backtrace+0x30) [0x17914d0]
/usr/lib/blender/blender() [0xd2b9d1]
/lib/x86_64-linux-gnu/libc.so.6(+0x354b0) [0x7f2a3cad74b0]
/usr/lib/x86_64-linux-gnu/dri/i965_dri.so(+0x5e2eb6) [0x7f2a0f6f5eb6]
/usr/lib/x86_64-linux-gnu/dri/i965_dri.so(+0x5e4559) [0x7f2a0f6f7559]
/usr/lib/x86_64-linux-gnu/dri/i965_dri.so(+0x5d1468) [0x7f2a0f6e4468]
/usr/lib/x86_64-linux-gnu/dri/i965_dri.so(+0x5d2345) [0x7f2a0f6e5345]
/usr/lib/x86_64-linux-gnu/dri/i965_dri.so(+0x3f34da) [0x7f2a0f5064da]
/usr/lib/x86_64-linux-gnu/dri/i965_dri.so(+0x3f3ddd) [0x7f2a0f506ddd]
/usr/lib/x86_64-linux-gnu/dri/i965_dri.so(+0x42a333) [0x7f2a0f53d333]
/usr/lib/x86_64-linux-gnu/dri/i965_dri.so(+0x17812e) [0x7f2a0f28b12e]
/usr/lib/x86_64-linux-gnu/dri/i965_dri.so(+0x17dda3) [0x7f2a0f290da3]
/usr/lib/blender/blender() [0xd2f76d]
/usr/lib/blender/blender(wm_draw_update+0x882) [0xd312b2]
/usr/lib/blender/blender(WM_main+0x28) [0xd2c678]
/usr/lib/blender/blender(main+0x376) [0xce5b96]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf0) [0x7f2a3cac2830]
/usr/lib/blender/blender(_start+0x29) [0xd28689]

Can someone help me? Please.

Maybe reinstalling the program could help?

this may sound naive but, what's your GPU?, sorry for posting this as a Answer but i can't comment yet (need more reputation). It seems to be a problem with your GPU driver. So you can try reinstalling that driver. Hope this can point you the right way.

does glxgears run? If not you will need to install compatible graphics drivers

I've got a similar issue with Ubuntu 20.04; blender 3.0.1 from snap (also 2.8.2 from apt) crashes when I start it. my GPU is a Radeon R5 M330 (yes, it's old). Not sure which drivers to install.


text:
How can I use nodes to make a Genshin-like grass material?
I have tried to make grass just like in Genshin, but it is still not like how I want it in EEVEE.

Game Screenshot

My Grass

Your grass is a little bit washed out, which actually annoys me about the grass in reality. Maybe you want to resign from Filmic view transform? Or decrease the strength of light.

It looks like the only thing you're missing is some color variation for each blade of grass.
If each blade of grass is an individual object, you can create variation with Object Info -> Random plugged into a Hue/Saturation node.

If you have a clump of grass where multiple blades comprise the same object but each blade is separate, you need to mix in Geometry -> Random Per Island.

I would suggest slightly bigger grass blades, with a gradient image for the color.
I think there's not as many individual blades in the game VS yours.
Lastly, and I might be wrong there, but I think that the game's blade's bottom are fading to transparent and are placed on a same color green surface.
Hope these bullet points help you!


text:
How to make edge half cylinder in edit mode?
I want to make selected edge to half cylinder to make the protruding brick parts looking like half cylinder without making new object.
I know I can extrude and bevel edge. But I want to know easier way.

If by 'Extrude and Bevel Edge' you mean something like this:

With faces intact, and 'Face Dissolved' so no internal edges
E Extrude one face, and then the other, snapping 'Active' to 'Vertex'
Delete end-cap faces
CtrlB the top face-selection with 'Clamp Overlap' set and a shape of 0.5, the default.
GZ (or whatever axis) the bevels back to the plane, snapping again.
M merge by distance.

It's tricky to think of a quicker way, for a one-off. (Maybe someone will come up with one :)  )

I didn't mean it. but after many search, that way was the best thank you!