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Hotkey to move up and down Bone Parent/Child chain?
I'm learning Blender having spent years in 3Ds Max. I'm used to being able to use the Page Up and Down keys in Max to move up or down the parent chain or hierarchy. Is there a hotkey to do this in Blender? For example, if I select the hand and want to move up to the clavicle.
Thanks!

You need to type the bracket keys, same in Pose mode, you can change the shortcuts if you want (right click on the function):

Thank you so much! I appreciate the help. I really hate that Google's search is so bad now that I couldn't even find a simple answer like this. Your help is much appreciated :)


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Weight paint by mesh element (For Hard Surface Meshes)?
I'm brand new to Blender - like today is my first day using it. I've used 3DSMax for 22 years though. Loving blender so far, but I'm rigging a mech (hard surface) and I'm getting a bit frustrated with the weight painting. In Max there's an option for me to simply select the elements of the mesh and assign 100% weight strength to a single bone. This is super helpful when rigging a hard surface model. In Blender though I can't for the life of me find a tutorial that shows how to do this. I tried switching to edit mode on my mesh, hiding everything but the element that I want to affect, but as soon as I switch back to Weight Paint, all of the hidden geometry re-appears which means the painting is affecting parts of the model I don't want it to.
Here's an example of me doing this in 3DS Max: https://youtu.be/4vn97_HywZg
Anyone know how to do this in Blender?
Thanks so much!

In edit mode, under vertex group properties, you can directly assign weight, without the need of weight painting.
If you select some vertices in edit mode, then switch to weight paint mode, you can enable the Face or vertex selection mask, to affect only selected.

Thanks Josh! I think I'll be able to figure out how to do this :) The pictures are well appreciated!

source: Stack Exchange

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

sort: votes


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Can you make a 3D background in Blender but draw in character animation?
I am quite new to Blender and all-things animation, but I really want to get started and I have a question.
I’m an avid fan of Japanese anime, and I’ve been a fan of Makoto Shinkai’s animation for quite a while. From what I see, I notice that he uses Blender for his background works, but a hand-drawn (2D) for his character animations. I believe he also use some Adobe AE and Premiere along side Blender. Is it done by using shaders? I’m curious whether anyone know how this is achieved as I really want to try out animation the way he does it.
Thanks a lot

Look at tutorials on animating with grease pencil, might be of interest to you

Blender is Ideal for this. Start doing even a little 2D animation, and you'll see why.  In Blender, 2D drawings are now  first-class 3D  objects.

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


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How to clean up interrupted edge loops using geometry nodes and fill holes with quad faces?
I've been working on a generated mesh where the topology is mostly good, but I'm encountering issues with edge loops being interrupted by misplaced lozenges. This recurring pattern is shown highlighted in the image on the left.

I managed to select and delete the problematic areas as they are easily detectable by vertices with fewer than four neighboring vertices. However, I need to exclude the mesh boundary edges to avoid deleting them also. While this method works to some extent, I think it is weak and prone to unintended effects. Maybe you can suggest a better way.
My main challenge now is filling the holes left behind after deleting these "offending" parts. Ideally, I want to achieve the result shown in the center example of the image. Specifically, I would like to:

Create a vertex at the center (in 3D space) of each hole.
Fill the hole with four faces, connecting the new central vertex to the surrounding boundary vertices.

I've tried several approaches but I'm stuck. Has anyone encountered a similar issue or can offer a solution for cleaning up the interrupted edge loops and filling the holes as described?

You could use Merge by Distance node instead of deleting them:

This works here at least. If the faces are more or less uniform in size then there should be a fair amount of difference between the distance of the paired vertices and the distance between their merged version and another merged version

You could also animate it if you wanted... https://i.imgur.com/mqs9DSD.gif No idea why you would want it but you could

Thank you, Cornivius, for taking the time to help me. Your solution works perfectly for the example I posted, but it depends on a specific value (the distance at which to perform the merge) that could cause issues in meshes where the features can have much more variable and unpredictable sizes. On the other hand, Markus von Broady's solution seems to work in all the cases I've tested without having to set this value. The animation itself was not necessary for me, but I believe his different approach represents the correct solution in my case. It would be fair to accept your answer, but...


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best way to remove create an object from image
Good day,
I know that this is probably a very simple question, but I have been looking and I have not found the exact answer to my issue.
I have this image and what I would like to do is extract the butterfly portion to be used.
I have tried several options such as mirror modifiers on a plane and then outlining one side.  I have also tried the knife tool.  The mirror modification was the closest but then when I went to fill the face for extrusion it gave me a bunch of extra faces outside of the butterfly.
My next idea would take a cube and work it the same way as the plane, but at least this way I would have faces.  Is that the best solution or is there something else that I could try?

You can import your image with Images as Planes, use the Knife tool to draw the edges along the shape:

Cut off the white part:

Give it a Mirror modifier (enable the Clipping option) and a Subdivision Surface modifier:

Extrude and bevel if you want to give it thickness:

Another solution would be to import an image with a transparent background, in that case you won't have to cut with the knife, but you won't be able to extrude.


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How would I apply a moving gradient across several objects
What I am interested in doing is taking a color gradient and applying across several objects.
This image is the best idea that I have to recreate what I am looking for.  For an example say that the circles at the bottom are actually cylinders spread out across a plane.  What I want to do is apply the gradient at the top across the cylinders.
To take it a step further, is it possible to animate the gradient to create a "breathing" type effect that shows up on the cylinders?

Add an empty, use this shader setup here for all nodes:

you can even animate the colors now via the empty:

of course you can use the x and z values as well, if you want to. Depending on the rotation/position of your object, you might have to take another axis and multiply/add values, than i did.

+1.. Not totally clear from the post ..but is OP's reference  a radial gradient? .. (Maybe need a Length in there)..

you are right - waiting for him to clear that up.


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How to make selected meshes move together in transform sidebar?
I must have hit some button, or typed a shortcut by accident, but my workflow has been shot in the foot by this problem. If I try to select multiple meshes and move them together by typing precise coordinates into the location section of the transform, only the mesh which was selected last moves. I've also lost the ability to deselect all using the "A" key, so there is always at least one mesh selected. I tried to restore blender's default settings but the problem persisted.
Here's a visual representation of what I'm dealing with:

For example, normally if I wanted to move both of these cubes so they were evenly placed on either side of the origin, I could just type "0" into the X coordinate and both cubes would move together.

Now, however doing this results in only one mesh moving. Strangely, if I try to select meshes at the same time using circle select or border select, there is still one mesh that seems to be dominant. Also, if I had another mesh selected, and then try to border select several other meshes, not including the first one, that first mesh remains "selected" and will be the only one that moves, even though other meshes are actually selected.

I have some long-winded work-arounds that I can use for the time being, but this is really slowing me down in a very inconvenient way. If I can't figure out what to do, I'm going to have to try reinstalling blender.

well it seems to me that what you describe is the normal way of working in Blender, maybe you confuse Object mode with Edit mode?

I can't rule out the possibility that's what going on. It may be that I got really used to working with joined meshes or something. I could've sworn that it worked differently earlier today though.

In 2.8 you can select 2 objects, go in Edit mode, and edit both the 2 meshes, it was not yet possible in 2.79

I would say, instead of using the property editor, which only edits the one active objects values, using numeric input which wil move all selected objects the same amount.


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Same object appears inside it in rendered mode
I was making sort of a 3D scenery but as soon as I went into rendered mode, the objects started reflecting weirdly, i got a new file and checked it again, so I saw a cube inside of the cube, it was like a reflection but i don't know what of. Please help me.

Hello. This looks like a GPU problem. Update your drivers

well, I checked my drivers and tired to update them, but it showed me that they were up to date, so that hasn't fixed it.


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Picks Origin Cant Move Cube
Absolute newbie here. Blender 3.6
To be used for 3d printing purposes.
I installed blender and watched a few videos. When I try to move the cube , it picks the origin instead. I have tried the drop down box and a few other methods that were suggested.
Uninstall and installed 3.3 and then 2.9. Still does them same thing.
Im come from SolidWorks background and when I first tried blender I might have rightclick a setting accidentaly.
But if I did wouldnt the reinstall cured it?
I have to run blender from a shortcut of the debug exe to prevent a startup crash.
Windows 10    16 Gig memory     Radeon HD 7570 video      1.3(?) 2 core i7 processor
Please help

Hello, maybe you have enabled the option called Transform Affect Only Origins on the top right of your 3D view? If it's not the case please show some screenshots?

Make sure that the Transform Affect Only Origins option is disabled:


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Blender closes when I select animate or render
Fresh install of 3.6 in school lab running WIN10 that closes/crashes Blender when you select animate or render. This even happens on a blank project. Video card is Radeon RX640, drivers updated, new Dell desktop Optiplex 3000. Any recommendations? Thanks.

we are no Blender developers here. I recommend using Help -> report a bug in Blender so that the developers can fix that.

Hey there! Is it crashing on a default startup file or you load a specific project? In the first case - it sounds like a bug. If you load a project file, please test it on a previous version of Blender. If it works there - report it as a bug. If it still crashes - then your file may be broken. Sharing your blend file can help confirming the crash on other machines.


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how do I change the dimensions of several selected identical objects - como altero as dimensões de vários objetos iguais selecionados
quando seleciono vários e modifico ele altera só de 1 objeto / When I select several and modify it, it only changes 1 object

You can change the Scale instead of the Dimensions, press AltLMB on the value, change the value and press Enter, all the objects will change their scale and therefore their dimension, at last apply the scale with CtrlA.
But maybe you should rethink the way you've worked your objects. For an object that is repeated like this, maybe you should use a modifier like Array, or use Instancing, or use Geometry Nodes, or use linked duplications (duplicate your object with AltD instead of ShiftD so that they share the same mesh).
For the latter, you can still link all the objects: do the dimension changes on one object only, apply the scale, select all the other objects, shift select the one that has been edited, press CtrlL > Link Object Data.

Try holding down the Alt key while modifying the value.

the Dimensions values?

Worth a try although I must admit I hadn't tried it when I posted my comment. In fact it only modifies the last selected object unfortunately. :^(

Yes it makes sense as each object may have different dimensions


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Exporting video from compositing
So I've only just started blender, and the first thing I did was use compositing to change a greenscreen to something else. I followed a tutorial, but when it got to saving the file, it got more vague. I set it to an FFmpeg video file where it says "file for..." and MPEG-4 as the container, which is what the video said to do, but I don't know what to do now. I rendered it, but from there it only let me save as still images. What do I do?

Hello, do you prefer to render a video or a series of images? Generally it is recommended to first render a series of images (PNG is better quality than JPG) then import the images in another blend file and render as video

When you run a "Render Animation" (I.E. by pressing ⎈ CtrlF12 or using the menu Render > Render Animation), Blender will write files as per your scene's output settings.
If you set a FFmpeg-encoded video, unless you had invalid encoding parameters (which should have canceled your render), you should see the video file in the folder you asked to be saved.
If you are unsure where that is, you can always hit the folder icon next to the file output path, which will open the folder in Blender's File Browser:

When using Compositing nodes
Make sure you output your node tree to the Composite node, this node is what is sent to the scene's file saving process:

Alternatively, if you want more complex file output (I.E. saving different versions of your compositing in different files, saving passes and whatnot), you can also use a FileOutput node. Although, it can only save image files, and Blender will still use the scene's render settings to output a file in addition to what you set up in the File Output node.


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Object is invisible, even though its unhidden
Everytime i create an object its invisible no matter what the object is, also im new to blender so sorry if this is stupid

Hello it looks like you've created a mesh > Circle, and it is visible, we can see the circle

If you've just added that Circle object, it seems to be visible to me! What happens if you add a solid object such as a Cube of Cylinder? - The Circle is just a ring of Vertices connected by Edges so won't show up very well when it's not selected.

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.


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Mesh gets deformed when parenting to armature

I used rigify. How to fix this? Here's the file:

The Copy Transforms constraint of these bones needs to be set to Local Space, not World Space:

These bones are available in this layer:

I have a question, when I move the head the hat doesn't move with it, why?

You need to do an Alt H to see the controller bones, some bones move the head but I'm not familiar enough with Rigify or Auto-Rig to tell you how it is supposed to work


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Why is my .FBX scene exporting with only one image texture applied to each mesh, when I have multiple?
I'm trying to export a scene from blender and use it in UE5, but the image textures are all wrong when I export it. I have a few image textures for each mesh, but it seems that only one is applied for each, causing some very weird looking texturing when exported.
note: the objects in the scene are photogrammetry scans
here is my scene:

here is the exported .FBX:

and these are my .FBX export settings:

here is an example of the three image textures present on a single mesh in the scene:

Maybe it is something to do with UV maps, which I admittedly know little about... I wonder also if there is a way to 'merge' all three image textures into the same image, maybe that's a dumb question. anyway thanks for reading.

Could you please share the inside material view of all materials? You can merge them into one image by baking all the textures.

hey Muzammil, thanks for the response. I'm afraid I don't know what that means, what is the inside material view?

I mean this one.
https://i.sstatic.net/9K3gE.jpg

@Muzammil i see, thanks. https://i.imgur.com/ndAxaFh.png here's the one for material in slot 1 of this object. it's just an image texture plugged into the base color

Having multiple materials on one object shouldn't be a problem. However, the materials can. Using the principbled shader with just values and UV mapped textures is the most standardized and well supported material setup for export. Are all your materials built this way? Otherwise, that might be the reason of the issue.


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How do I keep the noise in my Cycles render (animation)
Blender automatically reduces noise on Cycles renders now, but I don't want that. Googling this comes up only with ways to reduce noise, but I want to keep the noise you get in cycles.

It's the opposite to reduce noise, basically, turn in off denoise, lower render samples

@Emir Thanks, but how do I turn it off?

You can turn off the denoising in the render settings. If you want even more noise, reduce the number of samples.

Thank you! it was right under my nose the whole time.


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Emitted hair particles are pointing one direction
When I try to emit branches from a tree, all of them are trying to point into one direction, it looks like if they were following a path. Also, they doesn't sit on the tree itself they just randomly float around it. I've tried many things I found online, for example:
-Enableing rotation under advanced settings and rotating.
-Using modifier Stack
-Rotating the branch itself
-applying all transforms
but none of them seemed to work.
Can someone help please, I've been struggleing for days now.
Thanks!
You can find the project files on this link: https://drive.google.com/drive/folders/1q65u3Pf2utAFqM-MnEINlLLyMt6uAK9M?usp=sharing

Move the leaf mesh in edit mode so that the stem is at the object's origin point (orange dot).

Sadly, this didn't solve the problem, the branches still floating and pointing in one direction. I tried rotating the leafs in edit mode on different axises, but that didn't help either. The origin point was at the stem in all cases (I moved the 3D cursor to it and than moved the origin point to the 3D cursor)

select branch, set location to 0

set tracking axis like this:

set children to none

raise your number here:

result for 500  (emission number)

and just a hint: you can make even better and more customizable trees with geometry nodes, e.g. watch this: https://youtu.be/9mkJg6BZ65k

This really worked! Thanks a lot! This was a life saver.

Glad i could help

Thanks for the tip at the end with making even better trees. This was my second experience with geometry nodes (After Andrew's donut tutorial). It took a day, but I'm glad I tried it. So I made this:
Edit: Sorry i didn't know I can't attach pictures to comments.

You are welcome. If you want another tip:search and watch tutorials of Polyfjord. He is making the best tutorials for Blender right now (just my opinion)

I will check him out, thanks!


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recall saved position object
if the topic had already been discussed, I'm sorry, I don't know what kind of keywords to use for the search.
I come from the Autodesk "Vred" world and I speak of "Vset" a module where different positions of the same object are stored and can be recalled with certain shortcuts.
example: I have an ikea chest of drawers. by clicking on a vset set with the name "first drawer" the column was presented with the first drawer open and the others closed, then clicking on the "second drawer" Vset set the second drawer open and the others closed and so on, then finally with vset " tuttochiuso ”the chest of drawers was set up with the drawers all closed. it should be noted that it was not an animation but a way to speed up the view of the object without having to act individually on the objects with the drag to close and open.
so I ask you, hoping to have been clear, if there is a way to act in the same way on blender. I just ask you for the names of the modifiers, objects or command name and then I study it for myself. so far I have tried with animations but it did not convince me, with armor but I am too early in the program and I am still finishing a general course on blender. I ask you for a little patience.
thanks to many and i hope to read your answers
sorry my english, i use google translate
dd.

Maybe you should look into the new Pose Library. It's still a work in progress so it may lack some basic functions but it works:

You first need to activate the addon Animation: Pose Library. Then create an armature and parent each object to one of the bones with the parent to bone method: Select the object, shift select the armature, switch it to Pose mode, select the bone you want for this object and CtrlP > Bone.
Now in Pose mode, open the N panel, click on the Animation tab, move the bone(s) you want the way you want and click on the Create Pose Asset button, it will add the pose as a new thumbnail, you'll just have to click on this thumbnail to call back the pose.
To manage the assets (like to give it another name or put it into a catalog), open an Asset Browser window. Here you have a tutorial by The CG Essentials that explains more (but you'll find several other ones).
Other than that, you have the Action constraint, but it seems a bit more complicated.


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Texture paint is not showing up on my mesh object but it's showing up on the image texture to the right of my screen
I'm trying to texture paint in some details on the object I have created. I have added in the texture image initially in the shading mode > connected the node to the object colour which has worked (I have saved the image) and moved to the texture paint where the image texture shows up (saved the texture image again). when I try to paint onto my object mesh it does not show up in the location that I want it to. (it also at some points does not show up at all anywhere on the object) but my draw marking shows up on the image that is shown on the left of my screen. How can I fix this problem to be able to paint directly on the mesh object and have it show up in the exact place I want it to go? I have tried the following:

UV > Smart UV Project
flipping the mesh ( Alt >N > Flip ) (which did allow the paint to show up on the mesh at some points but not where I wanted it to go)
UV > Unwrap
Saving the texture image
Applied scale/rotation/all transformations (incase I missed this prior) --> no changes to the issue.

** One thing I think could be an issue is that my original texture image has been stretched on my object (after several searches and attempts to fix this I've given up on trying to get it to stretch proportionately on my mesh: In shading mode I added the Texture Coordinate but this didn't necessarily do too much ( I tried UV projecting also Unwrapping etc and nothing worked) although I quite like how it appears stretched on my object this could potentially be the issue as to why the paint isn't working.) if any one knows how I could also fix this that would be great as I would love to compare which texture image I prefer (stretched or unstretched)!
Any help would be greatly appreciated, i'm very new to blender so any step by step explanation would be very helpful.
https://snipboard.io/ID1LXQ.jpg
Here is the link to my screenshot^^ please let me know if this does not work.

Please share your Material settings or the .blend file with the image packed inside the file.

Thanks for your message, my .blend file is too large to upload so I have left a screenshot of the material settings here: snipboard.io/qGk470.jpg


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The pose bone matrix is reset to an incorrect value
I try to set pose bone matrices for setting location and rotation for bones, like this:
current_pose_bone.matrix = relative_matrix

The first matrix is assigned normally, but for some reason the second is not, the value is reset to incorrect, why does this happen?
First matrix (correct):
Matrix(((0.3579, -0.3624, -0.8606, 0.3231)
        (0.1733,  0.9314, -0.3201, 0.2978)
        (0.9175, -0.0346,  0.3962, 0.0259)
        (0.0000,  0.0000,  0.0000, 1.0000)))

>>> C.active_bone.parent.matrix.inverted() @ C.active_bone.matrix
Matrix(((0.35792356729507446, -0.3623908758163452, -0.8605601787567139, 0.323106050491333),
    (0.17334483563899994, 0.9313840866088867, -0.32011792063713074, 0.29777100682258606),
    (0.917519748210907, -0.03459606319665909, 0.3961828649044037, 0.025910720229148865),
    (0.0, 0.0, 0.0, 1.0)))

Second matrix (not correct):
Matrix(((0.3579, -0.3624, -0.8606,  0.3231),
        (-0.1733, -0.9314,  0.3201, -0.2980),
        ( 0.9175, -0.0346,  0.3962,  0.0259),
        ( 0.0000,  0.0000,  0.0000,  1.0000)))

>>> C.active_bone.parent.matrix.inverted() @ C.active_bone.matrix
Matrix(((-0.07111173868179321, -0.36239081621170044, 0.9293095469474792, 0.3231060802936554),
    (-0.009380493313074112, -0.9313840270042419, -0.3639175593852997, -0.2980000972747803),
    (0.9974243640899658, -0.034596025943756104, 0.06283299624919891, 0.025910764932632446),
    (0.0, 0.0, 0.0, 1.0)))


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rotation 2 objects in opposite direction like a door
I tried to rotate 2 object in opposite direction like a door
I select orientation mode (transform orientation) to local and individual origins
and set origins to the edges of the objects but it rotate also in the same direction how I fix it

You can do this with a Copy Rotation constraint.
Here I've used two planes.  The plane on the left Plane is the one I'll rotate.  The plane on the right Plane.001 is the one that will copy the rotation.

I add this constraint to Plane.001:

Like this, the doors will rotate in opposite directions, as Plane swings "in", Plane.001' swings "out."  To have them both rotate in the same direction simply select the Z` axis in the Invert row.


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Multiple levels of transparency in Eevee not working?
Think of a simple setup with three nested cubes - an outer, a middle, and an inner cube. They all get some simple material with the "Principled BSDF" shader. In the Cycles render engine you can decrease the Alpha value of the outer cube and the middle cube becomes visible. When you decrease the Alpha value of the middle cube the inner cube becomes visible (provided that the outer cube is transparent. So this is quite intuitive and straight-forward as expected.
The situation with Eevee is strange, however. First of all it is needed to change the "Blend Mode" in the additional material options to "Alpha Blend" and "Show Backface" needs to be disabled. However, I found that the Alpha blending is only working to the next surface whose materials "Blend Mode" is set to "Opaque". That is for instance, when the "Blend Mode" of the inner cube is set to "Opaque" (always visible), and the middle and outer cubes to "Alpha Blend", but the middle cube has got Alpha of 1 (so should be visible when the outer cube is transparent), the middle cube is not visible when I fade the outer cube into transparency. When the "Blend Mode" of the inner cube is set to "Alpha Blend" as well, then both the middle and inner cubes are like "not present" when I turn the outer cube transparent.
Is this behavior in Eevee normal or did I forgot some point?
Btw., the application behind that is to fade smoothly between multiple objects while the objects are slightly different in size in order to cope with "Z-fighting". At least with two objects this is working nicely. Perhaps there is also a different way to do this apart from such a nesting/transparency-approach. Ideas are welcome.
One work-around to deal with that issue might be to scale the objects dynamically (depending on the current frame) from within a script and also manipulate the "Alpha Blend" mode dynamically. I need to check that....
Thanks,
Mario

Is this behavior in Eevee normal or did I forgot some point?

This behavior is normal, assuming you're limiting yourself to talking about alpha blend, although there has been some evolution in how its been treated.
Rasterizers work by rendering materials one after the other.  When they render a sample, they write to a depth buffer.  When they are then asked to render another sample, they first check that depth buffer.  Is the sample we're about to write actually further away from the camera than what we've already put there?  Then don't draw it.  This works well for opaque meshes, and keeps performance high.
However, in the case of alpha blend meshes, what if we don't write our alpha blend materials in the correct order?  If we write something that should be alpha blended, then it will prevent anything behind it from being drawn by writing to the depth buffer.  Or, if we don't write to the depth buffer, then we render something behind it, we'll be occluding the transparent mesh inappropriately.  And even if that wasn't a problem, the rasterizer is only keeping track of a single layer: once you write alpha over some other material, you couldn't figure out how to write a different alpha between those two layers even if you could figure out not to occlude it-- the separate information about the alpha layer and the layer behind it is already lost, collapsed into a single value in the frame buffer.
It might seem that you could sort your alpha layers.  In some cases, you could.  In the general case, this rapidly becomes an immense problem.  Meshes themselves can have multiple layers, meshes can be concave, multiple materials can intersect, multiple times back and forth, and that intersection isn't at the locations of vertices, but in the middle of faces.  Accurate depth sorting of alpha blended meshes is a really expensive nightmare.
Because of this, you should only ever use a single layer of alpha blend.  I think there have been some changes to this over Blender generations.  It used to be that Blender would just try it's damnedest to sort, and then inevitably screw up the sort, and maybe you'd only find out on the render when your eyes suddenly appeared to turn inside out.  Now, it seems like it just renders the frontmost samples to a single alpha blend layer and composites it in.  Having been in that position of discovering that viewport sort was somehow different than render sort, I personally prefer just not even being tempted by something that will maybe only look right up until the point that I render.
However, there is an alternative, which is alpha hashed.  In alpha hashed blending, each sample is either opaque or transparent-- if the object has an alpha of 0.25, then 25% of the samples will be transparent.  Because each sample is either/or, there are no sorting problems.  This looks awful when rendering with a single sample, but starts to look pretty good when you get up to 32 or 64 samples or so.
Unfortunately, there are also limits to hashed alpha.  It is not exactly the same as alpha blend in its appearance.  (It is worse IMO.)  It cannot support colored transparency, because there is no "opaque in blue channel but transparent in red channel" possibility, there's just the one frame buffer.
My recommendation is save alpha blend for the very, very important layers of transparency, for the layers that just aren't going to look good with alpha hashed, and use alpha hashed for the rest.

Thanks for your detailed explanation @Nathan. I got the point and try to see how to deal with it at best.


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What is the best or proposed way to feed keyframed/animated parameters into Blender script?
In order to feed some animated parameters into a Blender application (meaning a more or less complex script) I'm actually miss-using simple Input-Value nodes in the compositor.
There I can set the desired keyframe-values and Blender animates them accordingly. From within the script I can grab the current value in the frame-change handler and process them further.
This method is working just fine but I'm wondering whether this is the intended method of doing such things?
Of course, one method is to implement all this keyframing and animation of these parameters inside the script. For a few cases I even did this. But it is not very convenient.
On top of that there is an issue in conjunction with the "Lock Interface" option during rendering an animation. I did not yet sort this out completely, but I often get crashes of Blender during rendering an animation, which is probably associated with multithreading-issues that can be probably avoided by using to "Lock Interface" option. However, when I use that option the animation of the keyframable Input-Value nodes is not working any more. I'm not sure whether this is a bug or a feature resp. the nature of this locking mechanism. At least the script cannot read the proper values any more. So when there is some other method this problem might disappear as well.
Thanks for any hints,
Mario

If you need to input values, you can make UI panels. You can define and save properties for many things in Blender like objects, materials, scenes and so on and you can read them with your script:
import bpy

bpy.types.WindowManager.int_prop = bpy.props.IntProperty(name = "Integer", default=15)
bpy.types.WindowManager.float_prop = bpy.props.FloatProperty(name = "Float", default=3.141592)
bpy.types.WindowManager.string_prop = bpy.props.StringProperty(name = "String", default="dsfsdvcx")
bpy.types.WindowManager.bool_prop = bpy.props.BoolProperty(name = "Boolean", default=False)
bpy.types.WindowManager.enum_prop = bpy.props.EnumProperty(
            #(identifier, name, description, icon, number)
    items = [('a','a','','',0),
             ('b','b','','',1),
             ('c','c','','',2),
             ('d','d','','',4)],
    name = "Enum",
    default = 'a')

class LayoutDemoPanel(bpy.types.Panel):
    """Creates a Panel in the scene context of the properties editor"""
    bl_label = "Layout Demo"
    bl_idname = "SCENE_PT_layout"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "scene"

    def draw(self, context):
        layout = self.layout
        col = layout.column()
        col.prop(context.window_manager, "int_prop")
        col.prop(context.window_manager, "float_prop")
        col.prop(context.window_manager, "string_prop")
        col.prop(context.window_manager, "bool_prop")
        col.prop(context.window_manager, "enum_prop")

def register():
    bpy.utils.register_class(LayoutDemoPanel)

def unregister():
    bpy.utils.unregister_class(LayoutDemoPanel)

if __name__ == "__main__":
    register()

See this: https://docs.blender.org/api/current/bpy.props.html also have a look at Python templates in the text editor's Templates menu:

You can create panels pretty much in every corner of Blender's UI wherever it's appropriate for your purpose.
It's also quite easy to make custom properties:

That would be bpy.data.objects['Suzanne']['prop'] it's not only for objects - lot's of thing can have those.
Operators can have their properties that are available in Repeat Last Operator panel, so you can write operators that can take input from there. See Operator templates in the Text Editor's Templates menu.
So those are a few ways, but you can take input from pretty much anywhere. It's Python - whatever you can do with Python, you can do it here.

Thanks @Martynas Žiemys! I did use the custom properties that I did add to the scene. It's working perfectly. It is also overcoming this issue when "Lock Interface" is active - meaning that the parameters are animated properly as well. So I hope that now I can leave the system working unattended for hours and days without crashes....


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Subdivisions of a plane somehow ignored when bending it with a Curve modifier and a BezierCircle
I'm trying to bend a sufficently subdivided plane with a BezierCircle. For the BezierCircle, in order to be as round as possible I added a subdivision modifier "Catmull-Clark" with 6 subdivisions for viewport and render. The circle became significantly more round with that change.
In the vieport the situation is looking as follows:

Not really nice, although the BezierCircle seems perfect..... Initially I did assume that this is just a viewport issue in order to reduce the complexity for fast editing. However, after checking this in detail the situation is looking identical in the render output. What can go wrong here?
Thanks,
Mario

@JohnEason Thousand thanks! That did the trick :-) "Preview Resolution U" was set to 12. When I pump it up to 64 I get a smooth alignment. And, indeed I can remove the BezierCircle subdivision.

Increase the Resolution Preview in the Bezier Circle properties (indicated below). If you set Render U to 0, the render resolution will be taken from the Preview properties. You can also remove the Subdiv Surface modifier from the Bezier Circle.


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How to convert from Y-up coordinate system to Z-up blender system?
I try to write owner importer for blender on python, but my matrices are made for Y-up system, so how to convert it to Z-up blender system?
After importing I rotate my armature 90 degrees on the X axis, but do I need to do anything with the animation matrices that define the location and quaternion or will blender do this automatically?
May be i need to multiply it by rotation matrix?
For example i have this matrix:
Matrix((
    (1.0, 0.0, 0.0, 0.00032),
    (0.0, 1.0, 0.0, 1.1003),
    (0.0, 0.0, 1.0, 0.006701),
    (0.0, 0.0, 0.0, 1.0))
)

Thanks!

It seems you simply need to rotate $90°$ around $x$ axis?

>>> mat = Matrix((
...     (1.0, 0.0, 0.0, 0.00032),
...     (0.0, 1.0, 0.0, 1.1003),
...     (0.0, 0.0, 1.0, 0.006701),
...     (0.0, 0.0, 0.0, 1.0))
... )
>>> C.object.matrix_world = mat
>>> e  = Euler((pi/2, 0,0))
>>> mat_r = e.to_matrix().to_4x4()
>>> C.object.matrix_world = mat_r @ mat

Your matrix then becomes:
>>> mat_r @ mat
Matrix(((1.0, 0.0, 0.0, 0.00031999999191612005),
        (0.0, -4.371138828673793e-08, -1.0, -0.006701047997921705),
        (0.0, 1.0, -4.371138828673793e-08, 1.1002999544143677),
        (0.0, 0.0, 0.0, 1.0)))

Thanks for answer! But why we multiply mat_r @ mat instead of mat @ mat_r? And do i need to do this for every keyframe matrix and for each matrix of bone for t-pose or only to root bone?

@SWR the order of operations depends on what you want to do, try both to see the difference - it either offsets first then rotates, or rotates first then offsets. In other words it either rotates in place (around its own origin, which is at world origin before offset) or it rotates around world origin.


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Blender, and it's relationship with VRam and virtual video memory
My PC has no dedicated video memory and due to this my blender freezes sometimes when I am using it. My question is, can increasing my virtual memory help with the occasional freezing of the software?

You can't do that inside of blender , in the software you can only adjust the rendering settings : samples , lights , shadow reflections , caustics , texture resolution etc.. to increase performance and lower memory usage .
To increase RAM dedication to VRAM you need to do that outside blender , i think it's in the bios settings or something like that , there are plenty of tutorials on how to do that ( videos , articles .. ) . Look on how to dedicate more RAM to VRAM on google and you'll find a way .
Good luck !


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Opening a hole the shape of an image
Good evening.
I am posing a question here, as I have a bit of a problem I'm facing with Blender. For starters, I'm not exactly experienced with modeling, so, even though I have managed to get myself past a larger number of roadblocks than I expected, some aspects of it still seriously elude me.
Mainly, I am trying to make a mesh that has a hole in it with the shape of a suit of cards. At the same time, I want that hole to have a mesh with that exact shape.
I have managed to import the image, and have it be its own plane. However, I am seriously confused on how:
1 - I can turn that plane into a shape;
2 - I can make a hole in the mesh I'm trying to mix it into
Would it be too much if I requested some assistance in this regard?
Thank you in advance.
m

Hi :). I seems you already have the heart shape modelled, so just cut it out of the card using boolean modifier. Or did I miss something?

Good evening. You didn't miss anything, I did. Like I mentioned, I'm sort of bumbling my way through this, so I didn't even know what that was. After looking it up, yes, that would definitely work wonders. However...
The heart shape is actually still a plane. Is it possible to turn it into a 3D shape (like if I wanted to turn a circle into a cilinder)?
I do owe you -massive- thanks for pointing me in that direction, though.

Never mind. I found out how. Solidify modifier.

Happy to help :). You can also directly cut out shapes with the Knife Project tool. Good luck with your project and welcome to Blender :))


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How to keep an orientation of component object on faces of base objects?
I have a problem when I use Tissue tool to make face structure like on pictures below. I don't understand why component object change its orientation 90 degrees when face of base object is changing. Do you have some ideas?

There are 2 buttons in the Tissue add-on that allows you to rotate a single face. Or you can use the UV map (another option, Rotation section > Rotation: Active UV) which works with a Mirror modifier. Have a look here: https://youtu.be/9RDIQvBB8XQ?feature=shared&t=930

It works! Thank you very much!

authors: Дмитрий Тригуб


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How to set the orthographic camera to match a specific width?
Consider a simple setup where the camera is facing a plane orthogonal. For further simplicity, assume that the camera is located at X=0 and facing along the Y-axis. The plane is also centered to the Y-axis. Now the goal is to set the camera viewing area in a way so that the left and right boundaries of the camera do exactly align with the left and right boundaries of the plane.
Of course, this should be done by entering the according numbers at the right place and not by tweaking the orthographic scale of the camera or similar, until it looks that it fits...
The background is that I want to render planes with textures of a specific width in pixels. I want to preserve that width in the output. I.e. when the texture is say 3000 pixels wide, the render output is also 3000 pixels wide and the plane fits horizontally the camera width, then there should be no horizontal interpolation during texture mapping and the initial texture quality is kept.
Thanks,
Mario

maybe I don't understand your question, the output size you define in format > resolution, and you could think of the ortho camera scale in Blender units, so if your image is on a 5 meters width plane you set the ortho scale to 5... I may be missing something though?

@alambre I didn’t know that… #LSNED

of course, but I misunderstand every other question that's why the comment... something else to consider here would be color management, sometimes a rendered texture doesn't look the same as the original picture, you got to see what works the best

@alambre Yes, intuitively I also thought that it should fit when I set the orthographic scale to the width of the plane (i.e. plane width=1 => orthographic scale=1). However, there is some relation with the actual resolution. For instance when the plane is 1m x 7.17m, and I set the resolution to 100x717 pixels, then I have to set the orthographic scale to 7.17. This method seems to work, at least. What you mention with the rendered texture quality is true indeed. Even if I feed the texture without a shader, I'm loosing contrast. I think I will ask this separately here....

yes, it's not the width of the plane, it's the width or the height, the biggest of both dimensions...

Yes, it's the biggest of both that has to be chosen. Anyway, I can deal with this now. I also found a solution for the image quality problem deep in Blender's manual....  The most important thing is associated with the "Color Management" whose default transition is set to "Filmic". This needs to be set to "Standard" in case the input image colors are to be preserved. Then the Render-Sampling needs to be set to 1 (at least for Eevee - Cycles I'm not sure). Together with the proper orthographic setting I can produce now an output identical with the texture (for testing only, of course...).


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CAD like snap base point for moving object
I am new to blender but have some experience on Autocad or CorelDraw.
I simply want to move an object. But not from the center of the object, but from some point on the edges of an object, e.g. one corner of a cube.
I am used from other tools to start move and then get asked "start point", where I can select some standard points of an object like "endpoint", "middle point" or simply interception point of two lines, and after that, define the "target point".
I wasn't able to find the way to do this with blender and would apreciate some help.

hello could you please show an illustration of what you want?

https://blender.stackexchange.com/questions/314440/accurately-rotate-plan-to-snap-to-another

@moonboots I don't know how I could illustrate my question. I would like to snap to the corner of a cube and move it to 0,0,0, the corner, not the center of the cube!

Make sure snapping is on in the header (magnet icon) and make sure vertex or other geometry element is chosen as snap target
Set a selection up
Start some transformation (like Move with G or Rotate with R)
While the transformation is ongoing, but before confirming, press B to set a base point
Click the desired based point with the aid of the snap indicators
Complete the operation by clicking the target placement.

Optionally, to get a midpoint between two points whenever snapping, press the A key to start the Add Snap Point mode, then hover over every vertex you want to average over and press press A to include them in the averaging point.
So if you want to have your base point as middle of a certain edge, after pressing B to get a base point, press A to start Add Snap Point operation, with the mouse cursor hover vertex 1 and press A, hover over vertex 2 and press A again, then click anywhere to proceed with the operation.
You can navigate the scene during transformation operations by pressing the Alt key in addition to the regular navigation mouse buttons.

I found the solution:

Move the cursor by holding Ctrl which then will snap the cursor to e.g. the corner of the cube or other selectable points
Set Transform Pivot Point to 3D Cursor
Select move
In the transform tool you can enter the coordinates to move to

This did the trick!


text:
Question on Sculpting mode
I was watching Youtube video about the sculpting mode in blender, and I realized in this Youtube video, around 01:28, you can see him drawing tiny lines on the dragon's neck with 6 px of brush radius.
Like this

But when I try it on mine, it just won't happen. I tried with Crease brush on 40 px radius. No matter how big the radius of the brush is, the pixels just keep collapsing like this. I did apply subdivision modifier before going into sculpt mode on the objects just to make them clean and smooth. Could it be the reason why it's not working for me?
I would like to know the correct way to use the sculpting brushes without limits and how.

Hello and welcome. Please use a title that matches the content of the post. It should read like a question, be descriptive but succinct, unique and identifying, summarizing the problem so that anyone searching for similar issues is likely to find this. Remove anything superfluous, avoid using words like "this", "help with", "issue" or "question about", instead describe what "it" is. Remember, your title is the first thing visitors see, answers you get depend heavily on it. See What is the problem of asking “How do I do this?"

Hello could you please share your file?

Hi, sure. I am new to both this website and blender. Sorry for my mistakes I made on this  post.
Sorry, I can't find a way to share my file here.

You can remove everything that is not relevant from the file and upload it here: https://blend-exchange.com/ (max. 20 MB). Alternatively, you can share a Google Drive link or use a share hoster to share the file if it's too big.


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Piñata hangs from rope animation

I want to know if there's a way to have the piñata/hook cling to the rope like in real life.
The rope currently has a shape key that has it drop down like this:

I have tried adding the piñata as a 'child of' the rope, which does move the piñata/hook with the rope but does nothing when the rope's shape key is set to 1.
would it be easier to animate the piñata manually so it looks like it's attached?

@RobinBetts the vertex parenting works, thank you!

It depends how much you want to animate versus simulate the swing.. but at its simplest, you could (Object Mode) parent the piñata to the line, selecting 'Vertex', that's Vertex Parenting.


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Blender cannot read file, permission denied
just downloaded blender, but i cant open any files in blender, it just says cannot read file: permission denied. I have all permissions, tried running it as admin and madee sure folder was read/writeable. I tried uninstalling and downloading from steam instead, still nothing. I tried different folders, different harddrives, no luck.
Thanks, Herm.

https://blender.stackexchange.com/questions/84602/cannot-save-blend-files-permission-denied https://blender.stackexchange.com/questions/91958/windows-10-blender-cannot-open-write-save-on-c https://blender.stackexchange.com/questions/33105/why-do-i-get-a-permission-denied-error-when-importing-an-obj-file

how do ypu try to open the files? What kind of files do you try to read? Please be more specific

You didn't even state what OS you're on...


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Geo Nodes: Resample Curve + Include Original Points (Without Splitting Edges)
I am trying to create a Geometry Nodes for hanging grass on the outside edges of planes.
After deleting the original faces, I resample the curve to add many points, then extrude along Z at a random value to create the grass effect:

However, I don't want the grass to go straight down, but be angled at a 45 degree angle along its normals.
The problem is, when I resampled the curve to add many points, I had to split the edges so the original points were included in the curve:

When I exclude the split edges node, I can first extrude along the Z, and then use that node's Top selection to size my extrusion along the normals, giving me the 45 degree angle:

However, when I include the split edges node, the normals aren't maintained:

I need both the original points in the curve, without splitting the edges to maintain the normals for the angle. I've tried both not splitting the edges and trying to incorporate the original points into the curve, and keeping the split edges in but trying to recalculate the normals with the "Set Curve Normal" node, but couldn't get either implementation to work.
My second problem is that, since I first extrude along the Z, then resize my extrusion along normals, I'm having a hard time randomizing along the angle, to get the straight hanging grass from the first image:

I've tried to give the same value to the Z extrusion and the Resize, with no luck:

Unfortunetaly, I just found out even in my above "good" normals nodes, I get inconsistent results when the seperate planes are too close on X and Y. If two planes are intersecting on X and Y, yet above and below on Z, the intersecting planes get inverted normals, and extrude inwards instead of outwards, while the non-intersecting planes have good normals.

First delete all edges interior edges, then delete the faces in case there's faces with no adjacent faces. Now you have the shape outline.
To get the 45º offset from the $Z$ axis, you can rotate the vector $\left(0, 0, -1 \right)$ by 45º on the axis made by the edge points, but the the the edge points won't necessarily have the correct order, making some edges flipped (they all need to point to the same direction in the edge loop).
To fix the direction, after converting the split edges to curves, we can reverse the ones that have the incorrect order. To detect the curves to reverse we need to first, before splitting and converting to curve, store in each vertex the index of the following border edge in face winding order, so this process needs to be done before deleting the faces.
For each vertex, get the next edge of its face corner that has a next edge with one face neighbor, but don't simply store the edge index since further in the node tree interior edges are deleted, invalidating the indices, store instead the trailing accumulation of: $1$ if the edge has one face; $0$ otherwise. This gives an integer equal to the index of the edge if edges that don't have one face were deleted.
Now that each point has the index of its following edge, first capture the edge index before converting to curve since the conversion changes the index order, then for each spline, reverse it if its first point's stored edge index is not equal to the captured edge index.
With the correct direction, store the rotation axis made by the two points of the lines. After that the curve resampling can be done, and merge the endpoints if desired.
Now rotate the vector $\left(0, 0, -1 \right)$ along the captured axis by the desired angle to get the offset direction.
Result:

Full node tree:

$\small\color{DarkOrange}{|}\hspace{2pt}\color{gray}{{\tiny\text{V}}\text{ 3.4.1}}\hspace{2pt}\color{DarkOrange}{|}$

This is incredible, truly an expert solution! Thank you for the work, I've been trying your file and it truly works with all possible shapes. There is a slight flaw, it only works if there's at least one internal edge to delete, not with a single face. Secondly, I want the grass downwards regardless of angle, this angles the grass more along the vertical slopes. The last thing (hope you can bare with me) is I've been truly struggling to upgrade to 4.0, I copied your nodes in 3.0 but I don't have "Evaluate on Domain" or "Evaluate on Index", I have too many python scripts I can't adapt to 4.0.

@MountainWhirl I fixed the answer, but could only downgrade to v3.4

Wow! What a legend! Works perfectly with my version.


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Thumbnail preview generation
Question: How can one autogenerate a thumbnail for a .blend file with a custom resolution
TLDR: How does Blender generate a thumbnail of a .blend file?
Blender has a tool called "blender-thumbnailer", which file managers use to generate/fetch images (previews) of the .blend files. These previews are in a set reselution of 128x128, in some cases even smaller if the blender window was scaled in some way when saving the file.

Above is an example of a .blend file which has been saved, and the thumbnail (preview) is successfully fetched by the program blender-thumbnailer by providing the following arguments:
blender-thumbnailer <input.blend> <output.png>

Above is an example of a .blend file with a generated preview image of the 3D file. The same command, blender-thumbnailer, has been run on it. However the difference between the two thumbnails can be noted:
Saved .blend file has:

UI menu
Background rendered
Material view

Generated .blend file has:

No UI menu
No background rendered (white background, the same on all .blend
files with generated thumbnail)
No material rendering

The saved .blend file is essentially a screenshot taken upon saving the file. That can be concluded by looking at the missing UI menu of the auto generated .blend file. The autogenerated thumbnail somehow generates the thumbnail in a background process, and I want to replicate that so I can have a custom resolution set for these thumbnails.
What I have attemped to autogenerate my own thumbnails for .blend files:
Using python and blenders API there are three operators I have tried to use

bpy.ops.screen.screenshot
This requires the .blend file to be open, which is neither optimal - or what I assume happens when blender-thumbnailer generates the preview

bpy.ops.render.opengl
Requires opengl, which can not be run as a background process

bpy.ops.wm.previews_batch_generate I do not know how to save the output of this operation, and therefore don't know if this is a way to generate previews. Either way, there is no option (to my knowladge) of scaling the output to a custom resolution

If you want to replace a blend files thumbnail this is quite involved as you would need to add/update one of the chunks of data in an existing blend file.
Older versions of Blender included a Python script to extract previews from the blend file into PNG's (now this has been rewritten in C++), even so, the Python script could be used as a reference for accessing the thumbnail preview.
Check https://github.com/blender/blender/blob/v2.83.20/release/bin/blender-thumbnailer.py - which is a primitive blend file reader, you'll want to read the TEST BHead, it's data consists of an int32[2] for the image width,height followed by the RGBA image data (where each channel is a uint8_t).
You can replace the pixel information, or change the contents and re-write the blend file.
Blender has logic for reading/writing this, check on use of the BLEN_THUMB_MEMSIZE_FILE macro to see where that is  handled.

Other considerations:

The TEST, BHead chunk may not exist and may need to be added.
Blend files may use ZSTD or GZip compression.
Blend files may be saved on 32 or 64bit systems (BHead4 or BHead8 in Blender's code).
Blend files specify their endian, checks for big/little endian files should be done.


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Multires baked texture is overlapped at some parts
My Multires baked texture is overlapped at some parts so the work doesn't look good.
Is there any option to make the bake not spread? The UV map doesn't overlapp

In bake settings set margin smaller:

Please note, that margin is created in purpose. Most engines generate mip-maps, so that this margin is important for low-scale versions of the texture. Without it, seems becomes visible

thanks! it speed up my work


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Why isn't it filling the colour I selected?

I'm very new to Blender.
When I try to fill my object with the fill tool it doesn't fill the correct colour. It's meant to be a light pink but its coming out more of a dark purple
How to fix this?

hello, could you please show a screenshot?

Please have a look at the answer I posted yesterday and try the proposed solutions (i just made some edits specifically for Grease Pencil). If this doesn't help with the issue, please share us a file with the issue via blend-exchange.com so that we can dig in.

Be aware that, unless you set your viewport in a specific way, you will never see your textures' colors "as is" on your objects, there are many shading and lighting systems that can change the look of everything.
For example ; if you use the Texture Paint workspace, it will set your viewport to Solid shading with the color display mode into Texture, but you will still have the Studio lighting ON. You can switch it to Flat so to not have any shade on your object:

If you want to paint with a full material preview, you can switch your viewport shading to Material Preview or even Rendered, but then you have to accept that you won't see your textures "as is", but instead a representation of its effect in the shader and with your scene's surroundings and lighting. But you can switch between modes at any time, and you can have the Image Editor open on the side as well.

For Grease Pencil, more often that not you don't care about shading effects. So not only you should pay double attention to the above to avoid surprises, but you should also make sure you set the color management's View Transform to Standard. The Filmic used by default is designed for CGI with high bit depth and wide dynamic range post processing, which you don't need when only doing Grease Pencil and can mess up your color work.

Furthermore, to help you setup Blender for Grease Pencil, you can select the 2D Animation environment when creating a new file or on Blender's startup splash screen:

This environment will setup Blender for you in a single click.

Could be this, but sounds like he has something like multiply set as the blend mode. Or he could be switching the wrong colours to the wrong side.


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Separating object by toon shading
How to slice a mesh based on "constant color ramp" as defined below into three objects?

I don't think it's possible to do that with the diffuse BSDF node before the color ramp.
One way to do something close is by removing the diffuse BSDR node and adding a group of Texture Coordinate+Mapping+Separate XYZ nodes:

This way, you can fix the axis chosen for slicing the object (Z axis in this example).
Then you can create 2 cutter cubes which will be positioned in that axis with both drivers, one per color ramp stop:
Select the second stop in color ramp, right click on its value and select Copy as new driver:

Select the first cutter cube, right click on its location Z value and select Paste driver:

Then edit the driver by selecting Scripted expression and in Expression multiply the position var by the Z size of your object (2m in this example):

The first cutter cube is now placed over that color separation and will follow that step value when editing:

Repeat this steps for the second cutter cube linked to the last step of the color ramp.
After that, make 2 copies of your object and set the following boolean modifiers to them:

Original object:

Copy 1:

Copy 2:


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How do I stop Soft Body from glitching?
I have a character rigged with its hair as a separate mesh, which is the child of the head bone in the armature. I have a soft body simulation running on the hair to make it drape down and move around, and it's working perfectly fine, except occasionally when I click to a frame, the hair will appear noticeably far away from where it should be, only to fix itself after a moment without me making and changes and it appears in the right spot. Everything has already been baked and cached, so it shouldn't be moving around at all. The hair also doesn't respond to the snapping around, so I'm not sure what's related to the simulation and what isn't. There are several other objects which share the same parent as the hair (such as the eyes, eyelids, and mouth) and none of them are jumping around in the same way.
I would be okay with this, except it does the same glitch in renders, without having enough time to fix itself, which leads to almost a third of my frames being worthless. If I go to the frames individually and click render, then they render fine. However, I'm working on a project that will eventually have thousands of frames, and I can't be individually checking for glitches and re-exporting them.
Is there a way to fix the soft body simulation permanently so it doesn't do this at all? I'll include screen shots of what's going on. I'd appreciate any guidance or advice anyone might have!

Here's the frame when I first view it.

Here's what it should look like, and what it goes back to if I linger on the frame for a few seconds.

Hey it's been a while with no response, so I figure I'll post my alternative in case anyone else sees this with the same issue. While soft body is nice because it updates quickly in real time, that's not a required feature for a project that you'll be rendering to video.
I was able to achieve nearly identical results using a cloth sim, without any glitched frames during renders. I just turned off the soft body, turned on cloth, and used the same vertex group I had for the soft body sim. Then I turned the stiffness down to match the settings I had before and placed the cloth modifier ahead of the subsurface modifier and baked the simulation. This worked for what I needed it to do, and solved the issue of the mesh jumping around and glitching.


text:
UV Packing texel density
Is there any way to pack UV or organise UV islands without changing there UV scale?
I'm trying to configure a whole scene with 20.48/cm UV texel density.
But when i try to automate the storage of my UVs by packing, it always try to fit the entire UV space and change the texel density of the islands.
Thanks.


text:
State color for bone properties does not respond (i.e. turn orange) to changes from keyframed value
Essentially, the state color does not change to orange when a transformation is made to bones in my armature, which makes it difficult for me to keep track of which transforms have had a keyframe added or replaced. For example:

A humble bone for IK posing at a time when it does not have any keyframes:

That same bone has been moved from its initial position, is still without keyframes, yet the state color for the transforms remains green rather than orange as though nothing has been changed

A keyframe for the previous location has been created, and the state color has turned to yellow as it should, yet moving the bone again (without replacing the keyframe) still does not change the state color to orange

This behavior is exclusive to this armature; other armatures in this project and others do not suffer from it. Because of this, I assume that there must be a setting somewhere for this particular armature that is causing this behavior, but none of them appear to have an effect. I am at a loss for what could be the source of the problem and would rather Blender notify me whether or not properties have been saved as it is supposed to.

The cause of this problem has been established as an NLA strip and track being added to an armature. Removing both allows the state colors to act as expected. I’m not clear on how any NLA data was added, as I don’t work with NLA and wasn’t even making edits to one of the armatures that developed this problem, but there is an easy way of resolving the matter.


text:
Issue with boxcutter applying weird size offset to cutters
As you can see below, whenever I start to draw a new cutter the cutter starts with some sort of negative offset making it very annoying to draw precise cutters. When I lock the shape and create the cut in the extrude phase the cut actually has the correct size (it then appears smaller - see screenshot below GIF). So the functionality seems untouched by this issue just the cutter shape itself visually has the wrong size.
I have re-installed both blender and boxcutter.
This suddenly happens (triggered by some action I don't know, I guess) during the modelling process. When I create a new file the issue is gone. Closing and re-loading my project file won't fix it either.
There is no setting in boxcutter that could cause this either.

Boxcutter is a commercial third-party addon so we can't really help with that, but have you applied the scale (Ctrl-A > Scale in Object mode) to your original object?

@JohnEason I know, but I have searched the internet for days now and have not found anyone with the same issue. Yes I have applied the scale.

Have you checked with the addon developers?

I'm experiencing the same issue. I believe it occurs when using smaller objects, as in my case, where I used 2 inches by 2 inches for precise electrical item modeling.

I don't know if this can be called a solution, or maybe a workaround, but I was also bothered by this problem and I started testing various ways to eliminate it.
I found out that pressing Ctrl at the start of cutting (first click) results in maintaining the dimension we planned to obtain (after cutting is completed).
In both cases below, I started cutting in the same place, but on the right side I started cutting while holding Ctrl.


text:
How to dynamically remove and add points to a curve resp. path via frame-change handler?
I'm having an application where I want to remove and add points to a
curve dynamically from within a frame-change handler.
Before you think that this is not good practice and I should better use
the start- and end-mapping feature of Blender: The actual application
behind that is described here: Troubles with creating a track that is evolving frame by frame This is also including a description why start- and end-mapping is apparently not suitable for that application (as of the state of my understanding as of this writing...).
At first I wanted to care about the removal of a number of points at the
end of the curve. I did run into an issue I was not able to solve yet.
Here is my according handler that is being called with every
frame-change:
def on_frame_changed2(Scene):
 current_frame = bpy.context.scene.frame_current

 # Force the EDIT-mode
 bpy.ops.object.mode_set(mode = 'EDIT')

 # Get a reference for the object that is containing the curve.
 trackpath_object = bpy.context.scene.objects.get('TrackPath2')

 # Determine the number of points we have in the curve
 current_point_count = trackpath_object.data.splines.active.point_count_u

 # If there are more points in the curve than the current frame number, delete
 # all points past the current frame number.
 if current_point_count-1 > current_frame:
     # Deselect everything so that we delete only those points we select later.
     bpy.ops.curve.select_all(action='DESELECT')
     # Select all points to be deleted.
     for i in range (current_frame+1, current_point_count):
         point = trackpath_object.data.splines.active.points[i]
         point.select = True
     # Delete all selected points
     bpy.ops.curve.delete(type='VERT')

The object "TrackPath2" is a path with poly-lines that has been created before.
Now the problem is that this is working fine as far as I did "some sort
of selecting" the path manually beforehand. I write "some sort of
selecting" because apparently this has nothing in common with the
selection within the Blender GUI. When I'm in EDIT mode and choose
"Select->All" for instance, there are selected all points of the path
but not the path as such. Instead, I need to click on either a point of
the path or on a link between two points. Then the path is "some sort of
selected", I can change the frame, and the frame change handler deletes
all desired points. As a result of the
bpy.ops.curve.delete(type='VERT')
operation the path becomes "some sort of unselected" automatically and I need to click on it again to make the script working again.
When the path is not selected in the way it appears to be needed, the
script is already failing at the evaluation of
trackpath_object.data.splines.active.point_count_u
Apparently, trackpath_object.data.splines.active is empty then resp.
returns "None". I can check this also in the Python console. As soon as
I click on the path it is not empty any more.
So the question is: How do I mimick this "click on the path" in the
script so that it will be working under all circumstances?

The problem is that trackpath_object.data.splines.active is not set when the path is not "some sort of selected". Apparently a specific spline needs to be assigned here. In particular this would be
trackpath_object.data.splines.active = trackpath_object.data.splines[0]

However, it is not needed to use or assign the active spline at all. Instead, trackpath_object.data.splines[0] can be used directly.
For those who are interested, below I'm providing the full script that is also including adding new points to the curve (new points are taken from a small list of sample-coordinates). I'm not sure whether everything is made properly there, but all in all it appears to be working nicely. Please excuse that the code is some sort of ill-formatted here. I don't know how to fix this in the StackExchange system. But the important things should be visible...
Important note on animation rendering: The script below does still contain some problem during rendering the animation. I did not sort this out completely, but it is associated with forcing Blender into the edit mode. I did solve that by removing this forcing into the edit mode for rendering the animation but did switch into the edit mode manually before. Although this is not really nice, it is forking fine for me so far. If anybody knows what the issue is and how it can be fixed - your comments are welcome.
import bpy

coords_list = [[0,0,0], [1,0,0], [2,0,0], [3,0,0], [4,0,0], [5,1,0], [5,2,0], [5,3,0], [5,4,0]]
def on_frame_changed2(Scene):
current_frame = bpy.context.scene.frame_current
print("Frame number = ", current_frame)

# Get a reference for the object that is containing the curve.
trackpath_object = bpy.context.scene.objects.get('TrackPath2')

# Set the active object (ToDo: Do we really need this?)
bpy.context.view_layer.objects.active = trackpath_object

# Force the EDIT-mode
bpy.ops.object.mode_set(mode = 'EDIT')

# Determine the number of points in the first spline
current_point_count = trackpath_object.data.splines[0].point_count_u

print("Current path point count = ", current_point_count)

if current_point_count-1 > current_frame:
    # We have to delete points.
    points_to_delete = current_point_count-1 - current_frame
    print(points_to_delete, " points have to be deleted...")
    # Deselect everything so that we delete only those points we select.
    bpy.ops.curve.select_all(action='DESELECT')
    # Select all points to be deleted.
    for i in range (current_frame+1, current_point_count):
        point = trackpath_object.data.splines[0].points[i]
        point.select = True
    # Delete the points
    bpy.ops.curve.delete(type='VERT')

elif current_point_count-1 < current_frame:
    # We have to insert points.
    # We limit the points have to be inserted to what we have available.
    if current_frame >= len(coords_list):
        print("Limiting points to be inserted")
        max_frame = len(coords_list) - 1
    else:
        max_frame = current_frame

    points_to_add = max_frame - current_point_count + 1
    print(points_to_add, " points have to be added...")

    trackpath_object.data.splines[0].points.add(points_to_add)
    # Walk through the new points and update their coordinates.
    for i in range(current_point_count,max_frame+1):
        trackpath_object.data.splines[0].points[i].co = coords_list[i] + [1.0]

bpy.app.handlers.frame_change_post.clear()
bpy.app.handlers.frame_change_pre.clear()
bpy.app.handlers.frame_change_post.append(on_frame_changed2)


text:
How to selectively disable multiple sampling while rendering with Eevee
I want to render a scene that is containing both regular 3D objects as well as planes containing pictures that are implemented using textures (think of a virtual screen in a virtual scene that is playing some video).
Formally, the size of the plane is calculated pixel-precise. That is, the texture on the plane is passed to the rendered output 1:1 without any interpolation or whatsoever. I did also set the interpolation mode of the texture to "closest" - just to ensure there is no interpolation. Now, the multiple sampling of the Eevee rendering engine is destroying that precision. The image texture is loosing sharpness, which is not desired here. When I set the sampling to 1, everything is fine.
Unfortunately, the multiple sampling is needed for other objects in the scene - i.e. some texts. So what would be needed here is some way to turn off that multiple sampling for
the textured plane. One way to walk around that issue would be a two-way process by rendering the objects where multiple sampling is needed and those where none must be used independently on transparent background, and combine both afterwards with some video editor. However, I want to avoid that, if possible.
Thanks for any hints,
Mario

Probably not directly an answer to that question, since such selective sampling is probably not possible in Blender as of today. But a suitable work-around:
I'm doing this sort of overlay not with a textured plane any more, but I'm using the compositor and an "Alpha Over" node in order to put the image sequence in place.
However, be warned: There is another pitfall that might lead to distortions even in the compositor. You have to take care about the "evenness" and "oddness" of the resolution of the rendered/total image size and the overlaid image size. If the total image size resolution is even (say 100 on the X axis), the exact center is directly between two pixels (e.g. between pixel index #49 and #50). Now, consider the overlaid image resolution is odd (say 25 on the X axis). The center is not between two pixels here, but is falling on a certain pixel - here index #12. In case the overlaid image is centered over the total image size, the pixel #12 of the overlaid image is falling half on pixel #49 of the total image and half on pixel #50. Of course, this is leading to distortions then. To deal with that, one has to either match evenness and oddness of the involved resolutions or by additionally offsetting the overlaid image by +/-0.5 in order to compensate for that shift.


text:
Error on any FBX import or export on Blender 3.6
Whenever I try to import or export a model, I get this error:

I have tried rein-stalling blender, and the same thing happens. This has only happened recently, and I did not modify Blender in any way that I know of. It just seemingly happened on its own.
I have Blender installed through Steam, so I don't know if that would cause an issue.
My other version of blender (2.8) is still totally fine, so this is specific to that installation in particular.
This happens with ALL FBX files, even ones I've exported from that same project previously.
Thank you in advance to anyone who might know a solution!

For anyone who finds this later: I found out it was one of my addons. I don't know which one, but I disabled literally every addon that isn't built in and it works now. I'll have to figure out the exact cause and specific addon later, but at least I know not to trust the error message.


text:
Baking a cube texture, only one face is visible?
I tried to follow a tutorial on how to bake a texture, but it does not work, the second cube has only one face from the first cube, I don't understand why, is it related to the seams ?

Hello please share your file: https://blend-exchange.com/

Were the two cubes in the same location when the texture was baked? They must intersect for the rays to hit the surface.

@Blunder great thank you !


text:
Changing the size of the box by the user
I want to create a box, export it using Blend4Web to html and post it on the site. And so that the site visitor chooses the width, height and depth of the box. I need these parameters to be changeable. Is this possible in a blender?

Blend4Web appears to be a third-party version of Blender so you should ask the developers of it if what you want to do is possible.

To make objects configurable you need to write custom JavaScript code using B4W API. But I don't recommend using Blend4Web at all, since it was deprecated long ago. For a modern and much simpler approach, use Blend4Web's successor called Verge3D.


text:
How can I close thick hair tips made with curves while keeping their tubular form?
I wonder if there's a way to close thick hair tips made with curves while keeping their tubular form (not with pointy ends).
I'm using Blender 3.6.
Thanks in advance!
It would be nice if the hair tips look like the example in the image below:

Check Fill Caps in your Curve to Mesh node and set the resolution of your Curve Circle profile to 4. Then add a Subdivision Surface node to round off the tips of the hair.

Thank you so much for your quick reply! Unfortunately, adding the Curve to Mesh node is making the hair curves lose their thickness. There must be something I'm doing wrong.
I'll put my test file at this link if you want to check it out:
https://1drv.ms/u/s!Ar5iNc2c3ZKIgbpvG4yb400GNTKfUw?e=fFeuS1

Here is how to set up your geometry nodes based on the file you shared:

You can go back to your second modifier : Set Hair Curve Profile
and play with the hair shape and radius.

I'm so thankful! This is exactly what I was looking for. Definitely, I have to keep learning about geometry nodes

That's the spirit! Keep on blending ;)

This may not be the exact answer you're looking for, but you can use Alt + S on each of your curve vertices to scale the profile of your bezier circle up and down, which means you shrink the bezier circle at the end of your path to narrow the end of the hair to a point. If you want more of a rounded end, just subdivide the the path of the curve near the end to slowly taper those curves.
Another way to do it would be to right click on your hair curves and go to Convert To > Mesh, then just Grid Fill each end and manually taper them how you want


text:
How to relink lots of missing image files with changed file extensions?
So here is my situation: I have a huge PBR Shader Library and most of the images in there are .png and .tif. I would really like to convert all of these images to jpg to save on disk space (This should save me aproximately 200gb of diskspace). But if i do this blender will lose all of the links to these images because the file extension changed. Is there a way to tell Blender "Hey here are all the missing files, just only look at the file names and ignore the changed extensions"?
I really dont want to do this manually... Thanks in advance for your help!


text:
A custom node group socket identifier
Is it possible to add a socket to a node group with a custom identifier?
So it would be:
>>> bpy.data.node_groups["NodeGroup"].inputs["My Socket"].identifier
My Custom Identifier

It is necessary because the "mapping" depends on it. I know I can utilize the order of adding, but a custom string is better.

A gist for testing.

A script to edit identifiers.
It requires Blender Asset Tracer and Python with Tkinter 8.6+. Blender's Python does not have Tkinter.

Can custom identifiers be set via code run on Blender itself nowadays (Blender 4.x), or is this property never meant to be set by us?

@UseTheFarce They are still readonly, so I don't think it can be. I still edit and create my groups in an old version of Blender. I need my node groups to remain backward compatible, but there have been changes regarding the internal structure of the node group sockets.


text:
Is there some way to show bending/folding deformation on a surface due to another object?
I have a platform that moves in a clockwise direction throughout the animation. then, another object needs to come down into frame and touch this object, dragging itself across it, which creates deformations on the surface as well as a permanent cylindrical divot. I can simulate the divot pretty easily by animating an expanding cylinder on the platform and making it invisible while also adding a boolean modifier. I've tried using soft body physics for the deformations before but it never seems to work. I apologize if this post seems like its missing details, but I cant share much as this is part of a research project. Any pointers?

Could you please share some drawings at least? Apart from Soft Body you have Cloth simulation or even you could fake the simulation with some shapekeys

See if this tutorial by PIXX0 3D helps. I've set the start position to where he is describing setting up Dynamic Paint. To leave the displacement, just don't check Dissolve on the Canvas setting.


text:
how to avoid collision while paper folding
how to avoid collision while paper folding

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 need to add topology, you need at least 2 edges where the topology is supposed to fold:


text:
Get a group note from the scope of a node within that group
Is there a way to get to the group node from the scope of a active node with the group? Let's say I have a material with a group (G). With that group I have let's say a Noise node. How can I get to the pointer of the group (G) if I only know the pointer to the Noise node. I've tried the "Parent" property but that always return "None".
The overall issue is, that I want to add a socket to the Group Output node from within the group. But it seems as if that can only done from outside the group. If I try to add a socket to the Group Output node directly, I get a "Cannot add socket to build-in node".
Thanks for any advice on that.

Can you elaborate why you only have a node, but without its group? what is the context for that?

I use Serpens, a plugin for creating addons. So my options might be limited or not as easily accessible as if I used plain code.
The addon that I want to create start from the selected node. In the case of this issue, the node is inside a node group. The question is, how to get the pointer to the container group if I have to pointer to the selected node. I hope this makes it a bit clearer.

node.id_data should refer to the node group.

Thanks, lemon. That works.


text:
Offset all keyframes to reposition animation
I have two mocap animations on a skeleton which are pointing in different directions, and their root bones are centered at different locations. For example, my walking-in-place animation is facing X+ and is at location [10,50,0] while my run-in-place animation is facing Y- and is at location [30, 10, 0].
I want both animations to face Y+ and be at location [0,0,0].
I cannot simply reposition and rotate the root bone, because the root bone also has keyframe data that would be lost.
What I can do is to turn on 'Automatic keyframe insertion', and then manually offset the root bone rotation and location by the relative amount on the appropriate axis. However, this is impractical as my animation has over 100 keyframes, and if I were to do this manually it'd take a really long time.
It should be relatively straightforward to write a script that does this automatically. For example, for the walking-in-place animation, I'd just tell the script to subtract vector [10,50,0] from the root bones location for every single keyframe, and then subtract [90] from it's Z axis.
However, I want to know if this functionality already exists either within Blender or in an addon. Seems like an issue that should be relatively common.

Why can't you just use the Graph editor to re-position the keyframes?
Select the keyframes you want to offset, grab, and move in the X direction:

You can also type in the exact number of frames you want to offset the keyframes by... positive or negative amounts.

@AlexRamallo - No problem at all, you can also type in a value after selecting your direction and it will move that many frames, positive or negative.

I believe the OP was asking how to reposition the animation relative to world space, not how to reposition the keyframes in the timeline.

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


text:
Custom properties for node-tree/network-style structure
Kind of a generic title, I know, but I haven't decided on any specific implementation at the moment because Blender offers many different potential ways to accomplish what I want.
Basically, I'm trying to setup a quick level editor for a project I'm working on. Rather than write my own from scratch, I decided it would be much simpler to just extend Blender with the Python API, especially since my requirements are very simple.
What I need is just a method to create a network of "nodes", and give each node a small set of custom properties including a unique 32 bit integer ID. An Armature, Mesh, or Curve seem like the most obvious objects to use, since they are easy to work with and are even connected visually in the editor. However, I can't seem to find out if it's even possible to add custom properties to each bone or vertex.
The only other solution I can think of is to use empties and connect them manually. This works, and I actually wrote a script already to do just that. However, working with a large map with many of these "nodes" would get very difficult to manage since the relationships/connections need to be input manually (e.g. each node has Next and Previous list properties which contain IDs of the nodes connected before and after). Also, there isn't any visual representation of these relationships in the editor (like a line connecting them as you would see in meshes or armatures)
So is it possible to add custom properties to individual vertices or bones? If not, is there a better method to accomplish what I'm trying to do besides creating and manually connecting empties?
Alternatively, if I DO have to use the empties method, is there at least some way for me to represent the connections between them visually in the editor? Something as simple as drawing a line between two nodes, or even just displaying some of the properties as text.
Here is an example of the data/relationships I need to store in properties as JSON:
{
"TestMap":[
        {
            "ID":0,
            "ntype":0,
            "RulesetType":0,
            "RPreset":0,
            "x":0,
            "y":3,
            "plist":[-1,-1,-1],
            "hlist":[false, false, false],
            "Prev":[0],
            "Next":[1]
        },
        {
            "ID":1,
            "ntype":0,
            "RulesetType":0,
            "RPreset":0,
            "x":1,
            "y":3,
            "plist":[0,2,1],
            "hlist":[true, false, false],
            "Prev":[0],
            "Next":[2]
        },
        {
            "ID":2,
            "ntype":0,
            "RulesetType":0,
            "RPreset":0,
            "x":3,
            "y":3,
            "plist":[-1,-1,-1],
            "hlist":[false, false, false],
            "Prev":[1],
            "Next":[3,4]    << Notice there's a fork here
        }
        ...
    ]
}

As you can see, the data is just basic numbers, lists, bools, and (possibly in the future) strings
Thanks, any help is appreciated!

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


text:
How to export model's mesh with adjacency information
I am working on raytraced engine, for faster ray queries I need my exported models contain information on their triangle's adjacency. How can I export my models along with triangle(face) adjacency information? i.e. triangle 5 is neighbour of triangles 2, 6 and 8.

Theres nothing really Blender specific here, the question is really about data-structures.


text:
How to add color to a black & white 3D laser scan (.wrl) file imported into blender?

I imported a 3d point cloud into blender .wrl file. The scan was without color just black and white. The image shows the point cloud, I want to add color to it, but not sure how I would do this.

Hello and welcome to BSE. When you have a point cloud, you basically only have a mesh of vertices. There are no faces but you need mesh with faces to put "color" or material to it. To convert a point cloud to a mesh with faces you could use this strategy: https://blender.stackexchange.com/questions/301218/how-can-i-convert-a-complex-point-cloud-to-mesh

Cool, Yes this will work, thank you.


text:
how to script python to get the index menu geometry node modifier?
i want to get  the 'Gold' value material in script python to use like this bpy.data.materials['Gold']

This question is similar to: Set group input to attribute in geometry nodes python without ops. If you believe it’s different, please edit the question, make it clear how it’s different and/or how the answers on that question are not helpful for your problem.


text:
Unexplained, automatically assigned parenting/constraints between objects
I'm encountering a strange issue in Blender. When I move/rotate/scale an object, random objects move along with it but with reduced influence. It's like they inherit the transformations somehow.
What I've checked:

No obvious parenting issues
No constraints detected
Tried Alt + P many times, even on the whole scene by selecting all objects and Alt + P'ing them

These objects seem to have been randomly assigned as if parented or constrained together, and I can't un-parent/clear them. They don't even appear to be parented in the usual way.
And they are many of them in the scene, it's ruining it.
Does anyone know how to clear these relations? I'm willing to clear everything.

pls provide blend file because we can only guess around. Thx for your understanding. Also make sure proportional editing  [1]: https://i.sstatic.net/UH82W0ED.png is turned off.

Oh wow ! That was it.
Never suspected that could affect surrounding objects.
That was driving me crazy. Thank you very much !

you are welcome

Take care. Opensource wins !

Make sure Proportional Editing is turned off.


text:
Crumpled Look After Rendering
I was trying to make a jet engine but encountered a baffling problem when I rendered.

One of the 28 fan blades looks kinda crumpled after finishing it's viewport render when it should be completely smooth as is in the viewport preview in the image below:

I tried recalculating normals to try fixing it but it didn't work.
How do I fix this?

Found out why:
when I used the spin tool on the blade to make it complete, I forgot to merge it. Found out after making a spin animation and it not being centered after centering origin.

Hi, Fin, ...Glad you found it!  Sounds like a simple slip-up, and you have  a fix without needing an answer.. either post a quick self answer, or we can close this one out.. whichever you prefer.

Stacked blades. When i used the spin tool i forgot to merge the stacked blades and it made the render glitch out a bit. So i just select all and merge by distance since they occupy the same coordinate in space.


text:
Duplicate Hair Curve Node Not Masking Properly in Geometry Nodes
I've been working extensively with the Geo hair system, but I've hit a roadblock when it comes to making the Duplicate Hair Curve node play nicely with vertex group data. Here's the situation:
Issue
The Duplicate Hair Curve node doesn't seem to respond to vertex group masking as expected. Despite trying various node setups, I haven't achieved the desired results.
Custom Masking Attempts
I experimented with custom masking Geometry Nodes, which worked well with an interpolate hair curve. However, when it comes to the Duplicate Hair Curve node, things get tricky. I've already created six characters using this node, so starting from scratch isn't an ideal solution.
Seeking Solutions
Is there a way to fix this without discarding my existing duplicate hair curves?


text:
Why does my cloth simulation bounce for a moment before settling down?
Whenever I play/try to render an animation with cloth simulation active it bounces for a second before settling down. Is there a way to effectively start rendering the animation from a point where it has settled and reacts to the models movement normally? The only thing I can think of is to add a couple of seconds to the animation before it starts to give it time to settle but that would increase the render time significantly.

You are right with the idea of starting the simulation before the start of the animation so that the first rendered frame uses a stationary version of the cloth.
Note that this will have no effect on your render times, the simulation only needs to be baked once before you start rendering and the cached results are then used during render.


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Material is not showing in eevee
When i wanna asign material to my mesh i'm not getting any result except this one:
I have no idea what is wrong, also on the carpet i cannot get material to work. Do not know if is it a Blender 2.8 bug or i'm doing something wrong. I hope that somebody will know the answer. Thanks in forward for the help.

Yes, the top one is correct, botom one is basic material for the walls and the celing. Also preview of the material is not showing texture which is seen in UV part.

Yes, edit mode, select faces, assign. I'm already have a headache from several hours of trying to find what is wrong. :)

Which object are you trying to put a material on? Just the carpet?

Later i found out that was my mistake. I did'nt change mix into multiply on the shader node and some other minor (begginer) mistakes. Now is ok, with another problems. Now i cannot get reflection from the mirror which i put over the bed. Reflection is shown in viewport but when scene is rendered there is just transparent glass. I'm using reflection plane, already spend around 6 hours, changed probably every parameter and still not figured out.


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noise.random always outputs the same value (Blender 2.80, Python, Compositor nodes)
I have code that procedurally generates images with a lot of random values for models, lighting, textures, etc.. Part of this process is randomly shifting hue/saturation/value in the compositor to get a wide range of rendered images. A problem I am having with Blender 2.80 is that the random values in the compositor are always the same each time I run the script.
In order to test things I wrote a simple script that imports a scene with the compositor setup and prints the hue value. The hue node uses the #noise.random() expression (which does work in the editor in all versions of Blender). Here is the code:
import bpy
path = "D:\\virtual_imagery\\render_data\\plot_row\\procedural-scene.blend"
with bpy.data.libraries.load(path) as (data_from, data_to):
    setattr(data_to, "scenes", ["procedural"])
bpy.data.scenes.remove(bpy.data.scenes["Scene"], do_unlink=True)
print(bpy.context.scene.node_tree.nodes["Hue Saturation Value"].inputs["Hue"].default_value)

Each time I run the script with blender 2.79 I get a different value. Each time I run the script with blender 2.80 I get the same value.
Am I missing something? Is it possible I discovered a bug?


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Object Shows up fine in Editor Render Shading Mode, but not in Final Render
As you can see below, when I render my scene, the icing from my doughnut disappears, however if you zoom in on the render, you can see some faint traces of the pink icing. Why does the final render (pic 1) not look like the render shading in object mode from the perspective of the camera (pic 2)?
Here is my blend file

Hey @cegaton, I read through this earlier, but my issue seems to be different, my object didn't disappear completely, you can still see pieces of it if you look at the first image. It is almost like the doughnut is expanding in the render and blocking the icing. I'm a noob at blender and it's possible I have something silly like overlapping nodes/faces, but am unsure of how to check or if it is a different issue.