text:
How do I rotate an object around an external axis without rotating it on its proper axis
Here is what I have until now:

I open a new "general" file.
I remove the cube.
I create Suzanne.
I change Suzanne's location to <0,0,3>. She is now looking to the left.
I set the origin to the 3D cursor (which is at <0,0,0>)
I choose rotation type "Axis Angle" and put <45°, 1,0,0> (she moved in space but now looks down ).
I set the origin back to geometry.
I set the rotation back at <0°,1,0,0> (suzanne is now at the same position but looks right up to the left)

What is my question: How can i do this operation is one step?
Why do I need this operation to be done: I want to create, for pedagogical purposes, a rotating cube, with the vertices labeled by text-numbers, but I want the numbers to face de user at all times. I could write a python script that does this but what will the animation interpolate between keyframes?

There are a number of different techniques.  Here, where you're concerned about animation and interpolation, it sounds like you want to inherit location from a rotating object, without inheriting rotation.  One easy way to get this is to use object constraints.  This doesn't involve Python, but it doesn't sound like you're married to a Python solution (and usually, when Blender supports something without custom code, I prefer the codeless solution; "once and once only" is the coding principle here: don't reinvent something that already exists.)
Make a Suzanne and two empties.  Move one of the empties to Z=3, then parent it to the other empty.  Now, give Suzanne an object constraint, "copy location", on default settings, and set the target to the elevated, child empty.  She copies the location of that empty without copying its rotation.
Try rotating the parent empty around.  You'll see that Suzanne rotates around the location of this parent empty but doesn't change her facing.  (If you'd like, you can still rotate Suzanne herself to change the facing.)

I want the numbers to face de user at all times

This is often called "billboarding", and there are other constraints that you can use to achieve this.  Here, my text object has a tracking constraint to track the camera:

We can see, on the sidebar, that the object has no transform, but because of the track-to constraint, it is pointing its Z axis at the camera and its Y axis upwards.

I opted for the second solution and it works fine. The numbers now always  face the user?


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Why is my animated object "shooting" around?
I am trying to animate a cloth simulation. I want to pull the cloth along the floor and drag it up to the ceiling and in between it will interact with some objects.
Two issues occur when I try to achieve this:

I have deleted all the keyframes but the cloth is still simulating? Can I delete the animation data somewhere so I can start animating from scratch?
I have two Hook Empties attached to two vertices and I wanted to parent these to another object to move the cloth around and drag it to the ceiling. However, when I add Location Keyframes to move it around, the cloth just "shoots" around. There is no smooth transition.

Here is the blend file:

It looks like a Cache problem, not sure what's happening, but change a parameter (like the Quality Steps) and play again and it seems to work this time

Ah okay. What about the object that "shoots" around? I updated the blender file.

again I had to change a parameter so that it calculates again and it works

I did change a parameter. The initial problem was solved, but now when I added back in the Empty to drag the cloth around, I still have the issue of the object behaving weird instead of following along the empty. That's why I changed the file.

I'm talking about your new file, it works fine if it recalculates, not sure what happens if it doesn't for you...

source: Stack Exchange

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

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How can I change the upper part of a straight cloth into a circular shape?
I made a curtain with a cloth simulation. However, the top part is still straight and I want this to be in a circular shape. I tried moving it along a BezierCircle, but that didn't do it for me.
As can be seen in the second picture, I want the pink line to be in the circular shape of the yellow line.
How can I change the upper part of a straight cloth into a circular shape?
Do I need to do this while animating or can I move this along a circular curve?
Here is the file:

If I try it with a rectangular shaped cloth, it works fine with BezierCircle.

Here is the file with the curve:
File Oct 23:

You can try with the Curve or the Simple Deform modifier:
First create a gradient vertex group at the top with the Gradient brush:

Give a Curve modifier to your curtain, select the vertex group so that only the top is affected. I had to align the curtain on X to make it work fine though because I was a bit lost with its orientation:

Second solution, create an empty and give your curtain a Simple Deform modifier, Bend mode, with the empty as Origin, Z axis and select the vertex group. Now move the empty on X and Y until you have something circular, it will be hard to fit the exact circular shape but you'll scale the top later in Edit mode with the Proportional Editing option on:

File:
For your current file:
In Edit mode rotate the mesh so that it is aligned with the X axis. In Object mode, right click > Set Origin > Origin to Geometry:

Switch the curve to Edit mode, rotate it 180 on Y:

Put the origin at this vertex location:

is there any other way? I am not sure if that has the result that I am looking for. I added another picture to show that it works perfectly fine with a rectangular shaped cloth. Not sure why it doesn't work with this one.

Yes you can do it with a Curve modifier, just select the vertex group so that only the top is affected, please see my edit

I cannot make it work.. I am getting a different result with that unfortunately. It sort of twists the top part of the cloth.

Please share the file with the Curve modifier

Added a second file to the question

Here is your file, corrected, I had to correct the vertex group, align the object with the X axis, apply the rotation, rotate the curve in Edit mode, change the circle's origin position, etc, now it seems good?

It does seem good. Can you maybe explain this further in detail? I would like to be able to do this myself :)

I've edited, I hope you understand everything?

I am not sure if I understand everything. Couple of questions:

Why would I have to  align the object with X axis, if the rotation XY is already at 0degrees? How do you align it then?
And why would I have to change the curve radius to 1 and do a SX -1?
My gradient in weight painting is not circular like yours, is that a problem? Do you also add another vertex group so you have two or do you delete the first vertex group?

Adding to the align object. If I do Object > Transform > Align object > Choose X, nothing happens?

Hello could you please share your last version? I've shared the file btw, maybe take a look?

I think the problem is that I don't really understand what I am doing in order to get the curtain to be in that circular shape on top. I added the latest file at the bottom of the question.

I've re-dited my answer, please check

Okay that works, can you maybe explain a couple of things?

Why does it have to align to the x-axis?
Why do I have to rotate the curve on Y 180 degrees?
Why does the mean radius of the circle need to be 1? Is that sort of the same as scaling?

I do notice I don't have a lot of control over scaling the top, but I guess that's related to this way of doing it. I also notice if I want to duplicate and rotate it, I have to apply the curve modifier, so it is a destructive method. I am just getting into geometry nodes. Do you think this would be easier with that? Well, not necessarily easier, but do you think I might have more control with geometry nodes?

It's better to have it aligned on an axis as it will get deformed according to the axis you'll determine (by default it is X). If the Radius of a vertex is not 1 the object will get deformed (il will bloat), it can happen if you scale the curve and apply the scale. If you want to duplicate your object, also duplicate the curve. I don't know enough about Geonodes, so I can't answer.

Thank you so much! Very clear!

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


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Why is the bevel/subdivision modifier messing up the mesh of my column?
I want to add a bevel and subdivision modifier to the column I made.
However, when I do this, I get the following result:
Why is this happening?
Here is the file:

EDIT: Okay, I changed the typology and recalculated the normals. So, the bevel works mostly. When I add Subdivision, something is still going wrong. So, where the mesh is getting messy that's also the part where the Bevel stops working. I feel like the typology is sort of divided into two. I added the new file.

You have flipped normals and overlapping faces:

You need to rework your topology, for example you could only keep the corner edges and fill with CtrlE > Bridge Edge Loops:

Second file: The problem is that for the moment your Bevel modifier is set to Limit Method > Angle, it creates bevel between the faces, even with a low angle, which prevents the smoothness between the faces. You'd better right click > Shade Smooth, select these edges, assign them Bevel Weight:

Then choose Limit Method > Weight:

Any ideas about the other issue that came up?

Please share your file again

I put the new file in there

I've edited my answer


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Generate rig produces a "bugged" controller
I'm having a really weird problem. I added a metarig to the scene, edited the pose to fit my character,, apply it as the rest pose, applied loc/rot/scale, and Generated Rig. The problem is that on the rig that it generates there is a "bugged" controller in the image below.

On the left side is the controller in rest mode in the forward position where it should be. On the right side is the controller in pose mode where it slightly rotates on the Z axis, despite it being locked.
I thought the solution would just be to alt+R and G to reset rotation and movement but for some reason these controllers will not reset to the rest mode. And I don't know of any other way to apply the pose mode position to these. Even when I go to the skeleton layer that controls the problem controller I can't fix it because you can't move the actual bone in pose mode and it goes to the rest pose in edit mode.
Does anyone know why this happens and/or how to resolve it?
Edit: just realized it causes problems with the hand bones and toe bone as well.
EDIT2: Here is the file. https://drive.google.com/file/d/1jk5RvFQrdlHRr4Pruz8Sk9br0QX3_IYm/view?usp=sharing
You can see how the rig adjusts itself by going from the rest position to the pose position in pose mode.

I noticed it too! I deleted the rig and generated a new one and that fixed it for me. Is this an option for you?

I looked into your file and noticed the problem. I looked to the knee of the metarig and it looks like your knee is facing backwards. You can see that because the pole is backwards. I posted several pics explaining this. That is why the IK is snapping weirdly when rotating the foot. I removed the rig and generated a new one using your metarig and it seems to have fixed the snapping issue. But there are several other issues with this rig.

While I'm a it, I would suggest you to move the kneecaps a bit to the front, so you're knees won't bend to the back when lifting the IK Foot.

Hope this helps!

Excellent response, thanks so much. I do have a more broad question; is it normal to have some minor discrepancies between pose and rest mode when using the rigify system? I've went ahead and made some changes to my metarig and its fixed it for the most part, but I still notice some small, negligible rotations on a few bones between the two. I'm wondering if this is normal for such a versatile, catch-all system or if the goal should be perfect symmetry between the two (pose and rest mode).

@LuckyCOINNNN
Nice to hear! I have had those issues myself. Normally when generating from a metarig, this is not suposed to happen.
I used a rig for a long time and lost my original metarig. Meantime I made some changes to the new rig and I too am facing this dicrepencany now. Especially on the knees when using the IK. But it doens't has influence on the end results and the rig moves just fine for me.

Try this:
In Pose Mode and Skeleton to Pose Position select all widgets/bones and press
Pose > Apply > Apply pose as rest pose


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How to edit Blenderkit files
I just enabled the Blenderkit addon but cannot seem to figure out how to edit the objects. I looked in this reddit thread and amazingly none of the solutions worked for me. https://www.reddit.com/r/blenderhelp/comments/hizn42/i_downloaded_this_model_from_blenderkit_and_i/
Making it a single user object, data, and materials did not work.
I do not see any option to append when adding a model form the Blenderkit asset bar (I even tried saving it and appending the object in another instance of Blender and it still would not let me edit it).
And when I right click I do not see an option to make local on outliner collection.
I am using Blender 2.83 if that makes a difference but can use 2.9 if need be.
Any other solutions?

Change the import settings from "link" to "append":

BlenderKits creates blend file in your disk, by the way.

I didn't see where this menu was at at first, but it is the expendable menu on the right hand side of the screen that I had mistakenly collapse with the N key. Got it.


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Why is my mesh so tiny when I port it to UE4?
I'm using metric degrees 0.01000 and my export FBX settings are scaled to 1.00 but when I open up the mesh in UE4 it looks like this.
I circled the tiny speck so you could see him. Any help?

How tall is your mesh in blender when you left click on its head and read the 3D cursor's location in the right panel (hit 'N' if its not visible) under "3D Cursor?" Your world scale settings are correct.

I edited in all the values in the op. Is that what you were looking for? I don't see the height of it.

Oh, your problem is that the dimensions of your mesh are tiny! A mere 1.6074cm tall—this is why it is so small in UE4. I would scale the character by about 100 times. A quick way to do this is to type 'S' and then '100' on your keyboard. After which you should apply the rotation and scale at the very least. I usually also apply the transform. Note: make sure you are in object mode and apply the transforms to the armature and the meshes of your character. In Blender 2.79 you have to do it one-by-one.

If you have multiple meshes in blender it can be tricky to measure them all together. One way I do it is by clicking on the top of the character's head: the 3D cursor will be placed there, and then in the right panel you'll be able to see the height of your character. It should definitely be somewhere between 1m - 2.2m tall for a humanoid character.


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Bones losing their weights in random parts. Can't figure out why
so when I put the rig in my character and did automatic weights everything worked accordingly. But since I started messing with my vertice groups and adjusting the weights, it all started messing up. My right side arm completely disconnected from the characters arm and the upper part of the thigh is disconnected to. I've been going back and forth from the mesh to the weight painting and vertice groups and can't figure out why. Any help?

if you go in Weight Paint mode, you can see for example that your right arm has no weight, so you must have made a mistake somewhere. Either reparent your mesh, or correct it in Weight Paint mode, or with the Vertex Groups of the Data panel. Also it's strange to give your Spline003 an IK constraint, but maybe you have your reasons...

Hi, thanks for your response. I have the right arm painted in my vertex group, but do you know why it wouldn't appear in the weight paint mode like it would anything else? I'm going to go ahead and fix it in weight paint mode, but I just want to understand why it wouldn't work the first time.

sorry I don't remember, I don't have your file anymore


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How do I add a picture to an 2D animation video
So I am making a video and I want to add a photo to make it look funnier, I know that it works on the General selection (the 3D one) but is it possible to put it in a 2D animation way, just like they do in Adobe Animate, or at least in the video editing section?
For example, at the beginning of his video he used two photos to make his eyes blink. Or how he used the UPS and Jimmy Johns logo, too. So my big question is, is that even possible, and if yes how?
2D animation with the picture of the eyes:

Picture of the logo:

Link to the example video.

Hi Pickme. Please be aware of that we try to help you but you have to do something for this. 2 sentences and a video link is...not enough. At least you should insert the timestamp of the video where the animation is - or better add a screenshot in here. So if you don't want that the question will be closed quickly because it needs more detail you should invest some time to write a better question. https://blender.stackexchange.com/help/how-to-ask

Did you see the video how he added the pictures can you even do that?

yes, i saw the video. But because the question is closed (which - in my eyes is correct because of lack of quality and information of your question) i cannot answer. And yes, of course this is possible with blender.

https://blender.stackexchange.com/questions/39876/movie-clip-on-plane

When you are in the 2D Animation workspace switch to Object mode (Ctrl+Tab, 4).
In the Object mode you can import a picture as plane:

enabled the Import-Export: Images as Planes add-on
press Shift+A, select Image > Images As Planes. (See Movie Clip On Plane for details.)
if you have a picture with more than one logo, duplicate the plane for backup, switch to Edit mode, and use the knife tool (k) to cut the area you need.

The logo's visibility can be controlled by keyframes. Just keyframe the Object Data Properties > Visibility > Show In > [X] Viewports and ... > Show In > [X] Renders to show and hide it when you want.
In the same way, it is possible to add 3D objects (File > Append ...).

To return to Draw mode don't forget to select the greasy pencil object ("Strokes") in the outliner, then Ctrl+Tab, 8 will work.

Thank you so much

well the picture did come up but when I did the visibility part it just kept showing

Have you changed the current frame? Select frame 1, hide object + insert keyframe, then select frame 10, and turn on visibility + insert a keyframe. Select frame 20 and hide it again + insert a keyframe. The 2D Animation has Auto Keying enabled by default & you might not need to insert a keyframe explicitly. Have a look here: https://youtu.be/SZJswvw9wEs If you can't see the keyframes in the timeline because the object is hidden change the editor from Timeline to Dope Sheet & enable Show Hidden (it's the button at the bottom of the picture at the right side, next to "Nearest Frame")

Ok got it thank you so much again


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I can't figure out how to displace lines based on height from an image. Is geometry nodes the answer?
I'm modeling a mountain and am trying to add trails to the top of it. I was able to displace the square mesh to form the mountain based on an image (bottom left of the first pic). However, when I tried to repeat it for the trails mesh (only vertices and edges) it doesn't work right.
Pic 1 - Correct displacement with an image for reference

Pic 2 - The second mesh I'm trying to displace.

As I searched for an answer, it seems like geometry nodes are the way to do it. Especially if I convert the mesh in Pic 2 to a curve. I've tried to learn how to use geometry nodes well enough to do it, but they're very weird to me and I haven't gotten it to work.
Does anyone have an idea of how to do this? With or without geometry nodes, just looking for any kind of answer. Otherwise, I have to move each vertex to the right spot by hand and it's really time-consuming.
Thanks in advance.

Hello and welcome. Instead of having users go through links and external sites please use the builtin tools to embed images in your post. See How to upload an image to a post? or GIF

How was the mesh trail on the 2nd pic created?

You can try shrinkwrap modifier to deform the second object onto the mountain

Since you create the displacement with a shader, you have no chance to use the mesh with Geometry Nodes. However, if you create the displacement with GN (or another modifier), then it can also be solved with GN.


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How I could model a slim cylindrical bottle with a dent on one side?
I tried posting around on various sites to get help creating a model similar to the images below. I'm trying to create a bottle shape that has curves that form cavities like the one in the image but I'm not sure how. Thanks!

From what I understand the cavity doesn't twirl around the object so you could probably do it with a cylinder that booleans another one, then apply and rework the topology:

Thanks for the advice! I think the cavities do seem to curve around the cylinder, I think I may have to twist the cylinder then do a boolean.

I don't think so, the silhouette would have been different, do you have other pictures?

sure! I found an image from the side here: https://i5.walmartimages.com/asr/3c05b557-be20-4cf4-a389-834232495e22.aa7a9cab42d545838edbe2214bd68a2f.jpeg?odnWidth=undefined&odnHeight=undefined&odnBg=ffffff

so to me it doesn't look like it goes around


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Can't use my GPU (AMD/WIN10)
Ryzen 5 3600, RX590, 16gb RAM, chipset & graphics driver up to date as is Windows.
I've uninstalled & reinstalled blender but still nothing.
Here's the debug.
I0611 04:36:52.234308 16820 device.cpp:47] CUEW initialization failed: Error opening the library
I0611 04:36:52.249321 16820 device.cpp:32] HIPEW initialization succeeded
I0611 04:36:52.249321 16820 device.cpp:34] Found precompiled kernels
Switching to fully guarded memory allocator.
Blender 3.5.1
Build: 2023-04-24 23:56:35 Windows release
argv[0] = D:\\blender
argv[1] = --debug
argv[2] = --debug-cycles
argv[3] = --python-expr
argv[4] = import bpy; bpy.ops.wm.sysinfo(filepath=r'C:\Users\xxx\AppData\Local\Temp\blender\debug_logs\blender_system_info.txt')
Read prefs: C:\Users\xxx\AppData\Roaming\Blender Foundation\Blender\3.5\config\userpref.blend
Registering file extension...success (user)
Info: File association registered

Saved session recovery to 'C:\Users\xxx\AppData\Local\Temp\quit.blend'
Writing userprefs: 'C:\Users\xxx\AppData\Roaming\Blender
Foundation\Blender\3.5\config\userpref.blend' ok
Info: Preferences saved

This site cannot help with Blender crashes or technical problems running Blender. There are no Blender developers here, nor does anyone here have any association with the Blender Foundation so your question is off-topic here. See "What not to ask" here. Report your issue via Blender's Help > Report a Bug menu.

It's probably because of the "CUEW initialization failed: Error opening the library" error. I have no idea what this exactly means. Blender 3.0 no longer supports OpenCL, it uses now HIP and hardware ray-tracing is not fully supported yet. Maybe your GPU is too old. Have yo tried Blender 2.9 LTS?


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Blender 3.2 : How to animate 3 different objects in one animation, please..?
It's a traffic light, with a blanking screen and 3 lenses, 1 per colour, each emissive.
I can animate 'Location' for each lens, forward and back, to hide them when 'Off', moving forward each lens so that it becomes visible. Blender plays the animations, in sequence, correctly, but each lens has its own 'channel'. I need to have these 3 animations in one 'channel' (for exporting, where anims are declared by key-frame range: 'Red' 1-50, 'Amber 51-100, etc...).
How may I merge my 3, separate, animations into one 'channel'..? Presently, any export only has one, but not all three.
Disclaimer: Whilst not exactly a 'newbie', I'm far from an expert.
Thanks in advance for any tips or tricks; I've searched around, but found nothing I can apply to my case.

Can your export include animation of a material channel?

To me, it's not clear what you mean by "channel". It's probably the channels in the action editor/timeline/dope sheet. But then I wonder how you want to merge them. If you have 3 separate objects and keyframe their attributes, which creates at least 3 channels then you cannot merge them.

'Channel', in the Blender I'm using, is the series of Key-frame points for each Property being animated. Typically, and in this case, these are x, y and z Locations. I don't know abot Material channels, so I'll pass on that one.
Since asking this question, I've had a colleague modify my animation such that it all exports correctly, with the 3 lenses moving as they should. My issue seems to have been 'over-thinking' my needs, and creating an 'All-Off' animation which made no sense, in retrospect. I think my issue has been solved, but combining animation data is still beyond me. Thanks, all.

The solution offered was to remove entirely the key-frames I'd set up for 'All-Off', which had all the lenses behind the screen. This is not necessary; to have all off it's enough to simply not move any forward..! The other difference was in the speed; I had made key-frames from 1 to 50 for each lens; 1 to 3 is enough. With the 'All-Of' eliminated, all worked, and with the shortened length between key-frames, it's all so much faster. Sometimes 'simple' is the key; t'was the case here.


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How to make this emeral shader look like this?
Is there anyone here who can show me how to make shading like this art?

https://www.instagram.com/p/CGryePsAuaz/ (high quality)
Thank you for the answer

Maybe try something like this - you may need to play with the two different Roughness values depending on your lighting:

Speaking of lighting - I used a couple of "Tricks" to make the Gem look appropriate - below are my world settings and lighting setup - the actively selected light is below the gem, the rest are above - all default 1000w strength.

That's an interesting world shader.  I'm going to add it to my collection.

That particular World Shader simply separates 2 Backgrounds - One providing only the image (or color), and the other providing only the lighting/reflections. In this case I "borrowed" the lighting and reflections from an HDRI image, but still kept the background roughly the same color as the OP's reference image.

all of my world shaders are very simple, they either produce no light, uniform light, or use the HDRI.  It's the way you mix the shaders that I hadn't thought to try.


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Broken Camera Zoom In Render
Anyone knows any possible way to fix the issue where my camera in render will be 10x more times zoomed onto something than it was originally in the viewport (ps - i know bout selecting different cameras..)
ps-i now also noticed that for some reason if i render single image in some parts of the video the sccene is too bright while in another itss too dark..  ://
The drive link to the file..
https://drive.google.com/file/d/1mrdpXDYf0ioREBrAJiDH5LpX-2QLuZrd/view?usp=sharing

Hello and welcome. Please don't write in all caps, it is the online equivalent of shouting, is harder to read and may be considered rude. You can use the [edit] button below to change you text into regular case.

I don't think it's a camera problem. You have a Collection 10 that is hidden in the viewport but enabled in render, it makes objects appear in render:


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Every Normal Map Bake of Mine Has Texture Glitches
Even tho I have followed like 5, 6 tutorials already the bake result does not look right.
Blend file of the mess I have...
https://drive.google.com/file/d/1SQHWamrD589K07PehckcB-0ZHNSdTB4u/view?usp=sharing
And this to be honest actually seems like my best attempt at normal map baking, even tho it's still bad as hell and I have no clue at all how to fix it...
I would really, truly appreciate any help, because this is driving me crazy.
Ps - the already baked normal map texture is applied to the low poly model

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

You need to unwrap the low-poly object properly. Your UV unwrap is bad because some UV faces overlap. As a result, these faces share the same spot of the image texture. This can't work.

There is only one short seam across the face. This results in one huge UV island that has a lot of compressions/stretching. You can see this when you use a checkerboard texture. The model's face has very little detail (small squares) and the back of the head has a lot of details.
Ideally, all squares should be the same size to provide the same level of detail. The head model at the right was unwrapped with Smart UV Project. It creates many UV islands but the level of detail is much better.

A proper UV unwrap gives you a much better result. For the bake, you don't need a cage since there are actually no opposite mesh parts where overlays could occur (such as armpits or between the thighs). Just increase the Extrusion value a bit, like 0.2 m. This automatically creates a cage by inflating the object.

Guess which one is the low-poly.

It's the right one.


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Making MotoBug fangs
I'm trying to make the fangs of MotoBug here:

I've tried using a cone and a cube, but I have failed to get either in the right shape. I've tried using some online instructions but they were from outdated versions of Blender.
Can anyone here provide assistance?

Hello ! Unless you can narrow down your question to specific problems, I suggest you go to a more back-and-forth platform like https://blenderartists.org/ cheers

This a lot opinion based question but I would use low poly (8 faces) cylinder, scale one side with 0 and add edge loops to give it some shape

Hello and welcome. Instead of having users go through links and external sites please use the builtin tools to embed images in your post. See How to upload an image to a post? or GIFs

Box modeling should work. Use a small plane, place it at the tip and then extrude it and follow the outline of the reference. Then extrude it to make it 3D and smooth is with the smooth brush (Sculpt mode). Add more edge loops to put it into shape. https://i.sstatic.net/3n6jk.jpg

One approach to start with a plane. Placed at the bottom, at the tip of the fang. Then you can extrude the plane upwards. Keep the vertices on the outline. Once you have covered the whole shape add three edge loops in the middle (top-down):

Done this, extrude the plane along the Y-axis to make it 3D. Add an edge loop in the middle to have more geometry to deform. Now, you can use the Smooth brush in Sculpt mode to smooth the edges and corners. Use a low strength (0.15).

Don't forget to check the face orientation and recalculate outside if necessary.
With help of the Loop Tools you can smooth the edge loops, too.
This is how it looks like with a few engraved lines, a level 2 Subdivision Surface modifier, and metallic materials:


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quick liquid shows a black box on 3d viewport
I can't seem to figure out why it shows a black box in 3d viewport.
I followed a quick liquid tutorial and I used a quick liquid function from the F3 menu, after changing the liquid from geometry to inflow it looked nice and so I went over to the 3d viewport and it's all just a black box. I tried putting lights and re-baking it but nothing worked.
This is how it looks in 3d viewport:

And this is how it looks in wireframe mode:

I don't know how to reply to the guy who commented on me so I'll just put the domain material here:

You have baked no mesh, there is only fluid data as particles. And what about your domain material, can you add a screenshot too? This complete blackness looks like you have no shader nodes or anything.

provide your blend file so we can check it out

@Chris https://www.mediafire.com/file/j6gwgerr1qhkr4j/quickliquidhelp.blend/file

Is this the correct file? You said you changed Geometry to Inflow, but the file still has a fluid object set to Geometry. And on my system it doesn't look black. But as I said before, you haven't baked the mesh - so whatever you do to make it not look black anymore, it will still look like a cuboid and not a liquid if you don't bake the mesh.

if you follow a tutorial and you are a bloody beginner you SHOULD exactly follow the tutorial because every little step is important and cold ruin your whole simulation

as i could see in your blend file ...you didn't follow the tutorial at all...

to get "something" change these settings:

change cache type to "replay"

change viewport shading to material preview

then you will get:

ohhhh thank you very much <3

You are welcome

Please consider to accept the answer @Moogle How this site works: https://blender.stackexchange.com/tour

About the blackness here. That's a bug in Blender 2.93 when Roughness value is set to a very low value (0.003...) and you have an Intel UHD Graphics unit or another affected GPU.
In Blender 2.92 it looks as it should:

liquid domain in Blender 2.92 with Roughness set to 0.000


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Why do some faces not emit hair?
I am trying to create a bit of a fuzz feeling to my object. However, when I want to add Hair by using the Particle system, the hair are not distributed equally over the faces, as you can see in the picture below.
How can I make sure the faces have equal amounts of hair?
Is the problem that my mesh does not have the same dimensions of faces?
Here is the file:

It may be pure hasard, maybe in the Particles > Hair panel > Emission > Source disable Random Order, or under Emission change the Seed value.

Check your faces orientation

@moonboots tried both - does not make a difference.

@Emir. Checked and everything is blue. I also recalculated Normals so that was also not the issue.

I also cannot subdivide the side faces to create a more denser mesh.

could you please share your file? https://blend-exchange.com/

I have added the file!

Check this, as if not the generated geometry will not be properly taken into account:

Concretely, the issue is most likely due to ngons, that you should avoid.


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Why does my bevel crease disappear when I add a Subdivision Modifier?
I created a custom crease in the bevel modifier in the upper section. I want to smooth it out a bit. However, it disappears as soon as I add a Subdivision Modifier, see 2nd picture.
I want to keep the crease in the shape as visible in the first picture.
Here is the file:

The Subdivision Surface will tend to round the shapse and make the concave bevel disappear, if you want to avoid that for some edges, bevel them themselves or use Ctrl E > Edge Crease. What shape would you like exactly?

I want to keep the shape as it is in the first picture, but I just want to smooth it out a bit.

why dont you just increase the bevel resolution?

The Subdivision Surface will tend to round the shape and make the concave bevel disappear, if you want to avoid that for some edges, put a second Bevel modifier in order to sharp the edges created by the first Bevel modifier, or use CtrlE > Edge Crease on the edge that you want to keep sharp:


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Glare node is visible in the viewer node but not in the render result
So my glare node is not working properly. I am working on an animation and in the composite tab the glare node is visible but not in the render result.

can u pls show us your render result?

Is it not showing after rendering with the Glare node already applied in the Compositor or does the render in the Image Editor not show the glare directly after adding the node in the Compositor? If the latter, make sure in the Image Editor you have enabled View > Update Automatically. But still, the Image Editor sometimes doesn't refresh. For single images you could also switch the image from Render Result to Viewer Node, it updates immediately and you could also save from there. Anyway, rendering an animation with automatic saving should show the glare in the saved files.

i saw and i have enabled the update automatically in the image editor.....i mean at starting with few projects the glare worked fine but after some projects the glare doesnt work properly anymore

ok i will share my render result


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Distribute points on top of instances doesn't seem to work
I'm trying to replicate this Houdini tutorial in Blender for practice purposes.
here is the link to the Houdini tutorial
https://youtu.be/zrmFLvwyZwY?feature=shared
Around 50 second mark.
I can't seem to achieve the same result as you see in the picture below. I can’t re-distribute points randomly on to the instances.
I've also shared my node setup.  Hope it helps to explains better. I would be greatly appreciative if anyone could help.

Do you try and change the seeds with some counter incremented every loop ? Because with fixed seeds, Random Number Generators are producing always the same sequence.

Hello Chien,
I didn’t propose you the same result as Houdini but at least your two problems are solved.

First the random problem you just have to install a counter that change the seeds of every random value at every iteration, as said StefLAncien.
The second was to distribute instances at the top : if you input instances then realized them you can sorted them with a Separate Components so the last instances will be the only one to interact because the rest are Meshes.

I hope it help.

EDIT:
I made a new blend witch look far more like the originals Houdini’s system.

First, I had at the end a Mesh Boolean, a  Mesh to Volume and a Volume to Mesh in order to mimic the VDB from Polygons. That mess a bit with the edges (you need to test it, if the resolution is too low you will have a poor the result, if its to hight tour computer may not like it), it’s called ‘Render Definition’ and you setup the Voxel Amount. This setup is switched on and of by the ‘Work Mode’.

In order to have a kind of fractal look, I used a ‘Decrease power’ witch is the Decrease value powered by the Counter. This output value is used by three setups: the Scale of the Instances, The Random Volume and the Depth of the instances on the surface (the setup of the Depth is limited by to values +/- 0.794655, witch is the ratio between the insphere radius and the circumsphere radius of a dodecahedron, so the instances are always touching the emitter surface).

But points are not equally distributed on the instances, at each iteration there is less and less points. So the amount of point have to increase at each iteration. To do so I use a ‘Density Power’ witch increase the amount of points according to the Power of a value you choose (Density Power) by the Counter.

It’s pretty cool too see what Geometry Nodes could achieve…
The update .blend

Edit:
And just for fun:

Thank you so much Fred & StefLAncien, the counter definitely helps. And thanks for giving extra tips too. You guys are awesome! Here is my result: https://i.sstatic.net/F1y0NSVo.png

@Chien I made a better Houdini look alike, I will edit my post soon, with explanations...


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Why are these two HDRI backgrounds different when they have the same settings?
I dragged a HDRI sky into my project as the world background and it has a very high contrast.
If i do the same thing in a new project it comes out how i want it, what could this be?

could you show the two settings and how you put them in your scene?

I've just edited the post to include photos, are there any more settings you would like me to post specifically? Thanks for your efforts! :)

Sampling settings are different, try adjusting that

From the shader nodes alone, it shouldn't make a difference. Maybe you simply don't use the same render engine between the two files? Otherwise, I suspect the difference is in the render settings. Although I'd be surprised if sampling or bounce settings would produce such a difference. However, I wonder if your current project has any form of color grading different from your default scene options. Look in Properties Editor > Render tab > Color Management. I bet you don't have the same options there.

I would suspect the Color Management as well as @L0Lock does. While the one sky looks "normal", the other looks overexposed and more saturated / contrasted. So if one is your project and the other a new scene, I guess in your project the settings are different then in your default startup file. So check the Color Management for the settings, especially View Transform, Look and Exposure.

@Emir Sampling does not change the exposure. It's the resolution of the sampling map and changing it has effect on memory consumption, noise and render time.

@L0Lock Thank you! This fixed it, it was a difference in the colour management settings, appreciate it!

Awesome! I posted an answer with more details and broader possible issues/fixes so that anyone with a similar issue can find a solution. Please accept it as answer and upvote.

Thank you again! Ive made it the answer and will upvote once i get enough credits (im new haha)

Things to check if they are the same when you have different renders:

Materials. If only parts of your scene differ, it's probably the main issue. Could be the nodes links, the nodes' settings, but also the materials properties (Properties Editor > Materials tab > Properties). If everything in the scene looks different, then unless you have a volume shader in your world's shader, it's probably not the culprit.
Render engine. Easy to overlook, but Eevee and Cycles don't produce the same result.
Color grading. That's what influences the entire scene's colors. So if everything is different, that's one of the possible culprits (Properties Editor > Render tab > Color Management)
Compositing. (note: as of today, this one can be the culprit only if the difference is visible on render and not from the viewport. But once the real-time compositor is implemented, you could have this issue visible from the viewport).
Render settings are different (samples, light bounces, clamps). Although this one will cause a different kind of visual difference.


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Decrease an object with values
Good Morning
I need to decrease an object on edit mode so it gets to 60cm height, but when I use the scale tool, it is proportionally decreased. How can I solve this?
Thank you.

Hello. Please provide a .blendfile https://blend-exchange.giantcowfilms.com/ so others can take a look.
Scale tool in 2.8 has three handles, each for one axis. But the scaling is relative, so achieving an exact distance might be tricky.

@JachymMichal (https://blend-exchange.giantcowfilms.com/b/6847/)

Hey there. This question doesn't allow answers, because it was marked as a duplicate. However I checked your file, and all I said before works. You can also switch blender to milimeters in Properties panel->Scene->Units. for control of the size.

@JachymMichal But how I can scale my object to 2cm height for example? Sorry but I still don't understand

You can just type it into the dimensions panel. Just type over the current value :).

@JachymMichal But into the dimension panel just exist a relative value. I need to change it for real value for example 2cm

not the scale panel. The dimensions panel has absolute values. https://imgur.com/a/8u1TeYN

@JachymMichal I find it. But the dimensions can't be changed on edit mode


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Two meshes stitched together
I want to simulate two pieces of fabric to act like they are stitched together so when I move a cloth, the outher cloth come with the first in a specific point of the mesh
Something like that (the last example with two meshes).
https://www.youtube.com/watch?v=vMVz2iafWt8

Please provide some context and explanation, don't just post an image

Probably apply a physics sim to the emptys that are hooked to the cloth mesh.

@DuarteFarrajotaRamos I want to simulate two pieces of fabric to act like they are stitched together


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the resolution of my model is too high
I made a model of an animal in the blender. I started by doing the geometry and then applied the modifier multiresolution to be able to later sculpted. At this moment the mesh has almost 8000 vertices, but the faces are not properly organized. What I wanted exactly was a way to restructure the mesh so that the model can be used in animation easily, but without losing quality. Retopology is an option?

I am having trouble picturing what your problem is... Do you think you could add a screenshot? To take a screenshot on a Windows 10 device, hold down Ctrl+PrtSc. To take a screenshot on any device running MacOS, hold down Shift+Command+4.

@YusaMac205 the images

@YusaMac205 What if I'm a retopology? I do not have better results?

The best (and proper) way is to retopologize the model (use snaping on face) with subsurface-workflow and adding the detail by baking a normalmap with the highpoly model.
Then you'll get a animatable mesh with fast rendering details.

If you just want your mesh to be simplified, you can use the decimate modifier and change the amount of total faces without modifying the shape too much.


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Random edges that don't exist?

The seemingly random edges that are crisscrossing everywhere do not exist and can't be clicked on. If I click on the connecting vertices, the "edge" disappears. Any fix other than just ignoring them? Applying subdivision or solidify modifiers seems to make them go away but I have to work with those off for now.
Answer: When I press "Adjust edit cage to modifier result" twice it just fixed it.

Hey, could you upload your .blend-file to https://blend-exchange.giantcowfilms.com? I'll have a closer look.
My first guess would be duplicate vertices. try "remove doubles" in Edit mode

@bstnhnsl It says error uploading so I'll try again in awhile. I did try removing doubles which didn't remove any. Also interestingly enough they don't show up in edge or face select, only vertex select.

Certain problem in this case might be different but if unnecessary geometry is only composed of edges you can subtract selection based on selection modes.
Deselect all, enter Edge selection mode, select all. Then enter Face selection mode. Selection will be edited accordingly as edges can't be selected in Face selection mode. Switch to Edge selection mode, invert selection, delete edges.

There are other ways to delete loose geometry, one way is to use Select > Select All By Trait and use options there.

I think I followed what you said correctly but for some reason the edges only appear in vertex select mode so this doesn't work?

@MarkRyan it is impossible to tell exactly what and why didn't work from several words description. Edges by definition can not appear only in Vertex selection mode without being selectable in Edge selection mode. You could upload the file to https://blend-exchange.giantcowfilms.com/ for more detailed diagnosis (pasteall.org if the first isn't working) or at the very least include more screenshots of what happens exactly when selecting them (file is better in this case).

Remove Doubles in Edit mode should fix the issue.
Switch to Edge mode and Remove Doubles
Also switch to Vertex mode and Remove Doubles
And even Face mode

Viewing it in edge or face mode doesn't display the edges but switching back to vertex edit brings them back.

Then you can just ignore it if its not affecting render quality

Why would remove doubles fix this?


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Painting over a texture doesn’t save?
When I paint over an old texture after UV Unwrapping it does not save and if I close the file after saving it is gone. Sorry I couldn't provide a file.

It's true, You have to save the image before saving the file and closing: you can do it in the UV/image window (Image - Save as image, shortcut F3).


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Getting the outside faces of a mesh?
1<- Side of chest1<-Neck
Can I select only the faces that are on the outside of the mesh? I just want to select all of the external faces.

Do you mean the mesh is solidified? Is it manifold or not? (are there any holes in it / areas consisting of only one side of faces etc) What does its geometry look like, is it all quads? Could you show some screenshots of the mesh in Edit mode?

@MrZak I'm pretty sure it's completely non-manifold and I am trying to just get the outside so I can 3d print it. I will add some screenshots to the original post. It's mostly quads. I would share the file but its 32 mb and honestly kind of disgusting I just threw it together.

@MrZak Just realized Google drive is a thing please tell me if there is any forseeable fix https://drive.google.com/open?id=1WNXgNJdAf5QwqHgWkjTY5oiwFYa-QQ-U


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point light strength in cycles renderer
I am trying to understand the exact lighting computation going on in cycles renderer. I've set up a test scene as follows:

Cube whose corners are at [-1, -1, -1] and [1, 1, 1]
Its material is set to [1, 1, 1] diffuse and [0, 0, 0] specular
Lamp at [0, -3, 0] with no distance attenuation (light falloff set to constant)
Lamp's strength is set to 10 with 0 as smooth value
Camera at [0, -5, 0]
Background light set to [0, 0, 0]

I've also disabled sRGB output (display device is set to None instead of sRGB). The exposure value is set to 0.
With these I am getting an image with cube's pixel value 65 at its very center (the region that receives light parallel to the surface normal). What can be the explanation of this?
I would expect something like 10 / (4 * pi). The reason of division by 4 * pi is that cycles defines point lights using power (in Watts). I also tried rendering in EXR format and it still doesn't produce the expected value.

Ok, I believe I solved the issue. Although my material's diffuse reflection was set to [1, 1, 1], for physically correct rendering the actual diffuse reflection must be divided by $\pi$. In other words, an energy conserving diffuse BRDF is defined as $f(w_i, w_o) = \frac{k_d}{\pi}$, where $k_d$ is the diffuse reflectance (note that my specular reflectance was zero so we are not concerned about the specular part).
This means that if light fall off is disabled, the actual radiance that gets reflected off the face of the cube is $\frac{10}{4\pi^2}$ (with physically correct quadratic fall off this would be $\frac{10}{4\pi^2d^2}$ where $d$ is the distance).
So in my case, this value turns about to be $0.253$ and that is what I see as pixel value in the center of the cube's face if I save the rendered image in EXR format.
As for the PNG format, cycles appears to simply multiply this number with $255$, the maximum storable value in 8-bits. This corresponds to $64$. This happens because I had disabled gamma correction. Otherwise, cycles would have gamma corrected the value before multiplying it with $255$. This produces a value of $138$ and I confirmed that by experimentation.


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Geometry Nodes: rotate each instance individually after resampling curve
First off, I am new to geometry nodes and am trying to understand what is going on.
I think my setup and question is pretty basic but I can't seem to get it to do what I want.
So I want every log to get a random rotation on the x axis. Every log is 3 meters, so the curve is resampled every 3 meters. On every point on the curve, 10 points are added vertically. Then I am adding a log on every point and want to give them a random rotation.
This is my node setup:

This is what I am seeing:

As you can see, the rotation is random on 1 mesh line, but then identical to every new point on the curve (next mesh line).
How do I make it so every log has a random rotation?
Here is the .blend file

Thanks in advance!

instead of 90 try pi/2 because blender expects radians instead of degrees. if this doesn't help, pls provide blend file so we do not have to rebuild everything on our own. Thx.

The amount of rotation does not matter for now. I just want to have every log to have an own rotation. I have included the blender file to the original post

It's actually quite simple. You are stacking instances on instances. so the 3 vertical lines are actually one object just duplicated 3 times. What you need to do is place a realize instances node in between the two 'Instance on Points'. By that you turn the instances into mesh data and they start to act separately

Edit:
You also need to change the Z rotation of each plank as the rotation of the instances before have been applied. I suggest to use curve to points node that gives you a tangent for each individual point you are sampling and align the plank according to them:

You can also get rid of the resample curve node at this point If you do not wish to make the original curve simplier

Thanks, this makes the logs rotate individually. However, now they are not aligned anymore with the curve.
https://gyazo.com/619478745aef6b59b21da22a7fac202e

The problem should be in the horizontal curve that defines the 3 points for vertical lines. Try recreating it as in the example I provided (in the GN from the beginning) and see whether that works. I had no such problem in the example. This way you'll know where to look

I am sorry, I know the problem is in the curve but I can't find the solution. In your example you are using two mesh lines and no curve as I am intending to use. Could you perhaps take a look in the example .blend file I provided in the original post? Thanks anyway!

Yeah it makes sense. By realizing instances you basically apply all transforms that happend to them before (including the rotation). What you need to do is rotate each individual plank not only along X axis as you wanted but also along Z-axis to align them with the tangent. Look into my answer, I'll put the script there

This is great, Thank you for taking a look!


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Geometry Nodes: Translate each instance by bounding box dimension
I want to have each instance touching the curve only on one side.
I can't find out how to use the bounding box dimension to offset the position of each instance.
I made a small blend file with a basic setup I must use.

This is what I am trying to achieve:

Here is the basic setup to start from.

Small disclaimer; I can't use Blender 4.X so please use 3.6 for example..

Whoops! I misunderstood, but future visitors might benefit from the alternative problem so I leave that answer. And as in that answer, take a look at a bounding box:

Imgur mirror (SE image hosting has problems)
The indices for y-axis alternate in pairs, so you can take verts #0 and #2 to get the y-dimension.

Imgur mirror

Imgur mirror

(Blender 3.6.10, ignore the first word in filename)
Blender 4.3
You can modify all instances to reposition their origins, though that's hard before Blender 4.0 as there's no "Split to Instances" node nor a "Repeat" zone. In the Blender 4.3 you have a "For Each" zone that makes it even easier, but probably slower (which can hardly matter because are you going to have millions of objects in a collection to make the iteration overhead matter?):

Imgur mirror

You are amazing! This is exactly what I needed.
There are more nodes than I expected to be needed but that is okay.
Thank you so much!

Hi Markus, I've come back to ask for some more help.. It came to my realization that in the blend file i need this setup to be in, I have multiple collections as input geometry where 'seperate children' must be off. In the file you uploaded the same can be demonstrated by also turning off 'seperate children'. Then you can see the bounding box data is from the first child. I actually need it to use the total bounding box of all children combined. Is there a way to do this? Please let me know if you need more explanation.

@Ramon if you want to use a common bounding box to offset them all, then they won't all touch the curve with one side anymore, is that what you want? Also how do you spawn them if they're not separated? If you separate for spawning but don't for bounding box, you get this: https://i.imgur.com/IPYcgYA.png and result: https://i.imgur.com/vwMFYQu.png

For this example they don't have to be seperated. As in my project file I have multiple collections to use instead of multiple objects to use. Let me show you what I mean. Turn of the 'seperate children' and you see it is aligned on the curve by using the bounding box of the first child. https://imgur.com/a/1YsRSqt But I need it to use the total bounding box of all children combined. Like this: https://imgur.com/a/TQB6lqR

@Ramon maybe like this then: https://i.imgur.com/WTHzu76.png and https://i.imgur.com/IM4qva8.png

Hi Markus, thanks again for the reply. That setup works when all instances have the same dimensions. Which is not the case in my project. https://imgur.com/a/N5HYU8a Here is the blend file which comes closest to my use case. If you'd have the time to look at it I would really appreciate it. https://blend-exchange.com/b/S53xeY7a/

@Ramon my last screenshot was on your file, where the instances don't have the same dimensions and you can even see that on the screenshot

Yes I can see that. I mean when using different collections which have children with different sizes. In my previous comment there is a blend file with a setup which uses more collections as input instances.

Let us continue this discussion in chat.

I checked the result of Bounding Box node with Set Geometry Randomization operator (it doesn't work on 3.6 unfortunately) and the indices are stable. This makes the setup much easier. Take a look at a bounding box of anything with x-thickness:

Imgur mirror (SE image hosting has problems)
Even indices are on the left side, and odd indices are on the right side. So the strategy is to create bounding boxes, delete all but first corner for them, realize them, and now you have as many points as there were bounding boxes, so as many points as there were instances, and indices match. Then do the same for 2nd corners and sample their positions by index to calculate x-dimension:

Imgur mirror
The Absolute node isn't actually necessary there, as fixed bounding box indices ensure #1 vertex is always to the right of #0. The "Mix" node might be confusing. It's role is to sum two halves of accumulated distances, because each offset is half previous bounding box and half current bbox.

Imgur mirror

(Blender 3.6.10)

It's insane how they haven't made geometry fields available yet.... this bounding box thing should be ridiculously easy.

Hi Markus, thank you for your quick response!
I am not sure if we are on the same page though.
I don't need the blocks to touch eachother, I need them to touch the curve with one side only.
So in theory I want them to translate half of their individual size. In my original post you can see a screenshot of what I am trying to achieve.

@Ramon Ohhh that should be simpler :D Though now that I look because I used a bounding box of a curve it doesn't show Y/Z differences so I need to redo that screenshot, might as well write a separate answer then


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Geometry nodes: translate asymmetrical instances with their Y+ bounding box value relative to points position
This is a follow up / more in depth question about translating instances by their bounding box size.
I would like to translate each instance left with their Y+ value relative of the point position so they will align left to the curve.
This is the basic setup:

And this is the desired outcome:

Is there any way to do this (in blender 3.6) using geometry nodes?
Here is the basic setup blend file you can use:

Thanks in advance for any help!

But the objects seem to be not centered on the curve, at least not all - so half the size of the bounding boxes will not align them all. I'm not at a PC right now so I cannot write a proper answer. But what you need to do is get the maximum Y values of the bounding boxes and subtract them from the objects' positions to align them.

I think this question is very very similar to this one: https://blender.stackexchange.com/questions/327302/geometry-nodes-translate-each-instance-by-bounding-box-dimension

@GordonBrinkmann, you are totally right. Half of the boundingbox won't match indeed. Subtracting the maximum Y value from the point position should work. The problem is that I don't know how to do it per individual instance.

@DanielMöller, yes it is. It is actually a follow up question.

The other answer totally tells you how to do it... just replace the average of the box with one of its max or min X.

Here, I made a node group that makes it easy to get bounding box for random instances.
All you need is to subtract the minimum or maximum from the bounding box in the direction you want:

Geometry nodes
In the example, I subtracted the X from the left side of the BBox (because that value is usually negative). This displaces the instances to the right (if you want to the left, subtract the max).

The Random Instance BBox group
This group wraps a random selection of an instance and returns its bounding box:

The Instance BBox group
This group returns the bounding box for a given instance.
It explores the fact that:

The bounding box has 8 points
The lowest point in the bounding box has index 0 (thus in the realized geometry, we multiply the instance index by 8)
The highest point in the bounding box has index 7 (thus we add 7 to the index)

File

Wow, thank you for the great write up! It makes it so much easier to understand what is going on. This is the setup I was looking for. Thank you


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Make plane follow GPS elevation data
I'm trying to create a track mod for Assetto Corsa of the Kartodromo Evora track.
Initially I tried importing elevation data with BlenderGIS (OpenTopography), but the data available there isn't accurate enough. Luckily, I have a GPS trace of myself driving a kart there recorded with very good accuracy.
This is the track model I made using BlenderGIS:

And this is how the GPS trace looks like: (I have a list of longitudes, latitudes and altitudes)

I haven't really done anything advanced in Blender yet, so I don't know how to attack this one. The goal is to make it so the track is elevated according to the elevation data from the GPS trace.
The track model is also connected to the off-track area, where I don't really care about the elevation, but it's important that the off-track and on-track connection is smooth and doesn't contain any holes, so when modifying the track model elevation I will also need to modify the off-track model so that it all stays intact.
Note that I can't just recreate a plane along the GPS trace as it does not follow the middle of the track and does not contain any information about the width of the track. I must use the existing track model and apply the elevation to it.
Any help as for how should I approach solving this will be much appreciated.

Could you provide your Blender file using https://blend-exchange.com/, with your GPS trace already imported ?

Sure. How can I import the GPS trace though? Currently it's just seating in some CSV but I can easily convert it to anything else

Open the csv in Blender, then pack external resourvces to embed it.

Done, attached to the question. Let me know if I did anything wrong.

This script should do the trick.
import csv
import bpy
from bpy import data as D
from bpy import context as C
import bmesh

OBJECT_NAME = "TestObj"
CSV_PATH = r"Paste the path to your csv here"

coords = []

with open(CSV_PATH) as csvfile:
    reader = csv.reader(csvfile)
    for row in reader:
        coords.append(row)

mesh = D.meshes.new(name=OBJECT_NAME)

obj = D.objects.new(name=OBJECT_NAME, object_data=mesh)

C.collection.objects.link(obj)

bm = bmesh.new()
verts = []
for i, co in enumerate(coords):
    if i == 0:
        v = bm.verts.new(co)
        verts.append(v)
    else:
        geom = bmesh.ops.extrude_vert_indiv(bm, verts=[verts[-1]])
        new_vert = geom['verts'][0]
        new_vert.co = co
        verts.append(new_vert)

bm.to_mesh(mesh)

Once you generate that you will probably need to reorient/scale the mesh, it might be a bit all over the place. Then just Alt+C, convert to curve, then you can extrude it and control the twist to change the plane of the road.
After that you can convert the generated curve to a mesh and shrinkwrap your existing mesh to it. Something like this:

Correct me if I'm mistaken, but this simply takes the GPS trace, then creates a brand new plane following it, right?
If that is the case, please read the note I added to the bottom of my question - this solution won't work for my use-case.

I edited my answer, I think that this should work for you.

Yep, ok, this works. Well, the general idea works at least. Had to do a lot of manual tweaking - but I guess that's to be expected. Thanks!


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Export internal faces material booleans
Is there a way in Blender to export an "unapplied" Boolean but have the subtracted object show up with its inner material on export? I attach an image. When I export, I don't get the interior color of the subtracted material.
I want to paint the "n" faces of an interior of a cube subtracted by "n" objects with their "n" faces.
To illustrate a basic example.
Suppose I have this:
https://i.sstatic.net/mpF7g.png
And we apply booleans, with "exact" we have this:
https://i.sstatic.net/0nNG0.png
When I export with "exact" I have:
https://i.sstatic.net/Km8hV.png
If I put it in "transfer" to get a color of the faces I have
https://i.sstatic.net/LWlKY.png
The export does not make any faces.
https://i.sstatic.net/w8hRx.png
This is not a bug?, that is, I can see exactly one of their faces, while with transfer I don't see any.
Maya can do it, but I don't really like the way she does it.
https://forums.autodesk.com/t5/maya-forum/boolean-tool-conflicts-with-materials/td-p/11729151
I've been reading this, but I don't know if it's related.
https://devtalk.blender.org/t/whats-with-the-new-boolean-modifier-materials-behavior/25827
Is there a way in Blender to export an "unapplied" Boolean but have the subtracted object show up with its inner material on export?

Please insert your images directly into the question rather than requiring folks to click on links to see them! https://meta.stackexchange.com/questions/75491/how-to-upload-an-image-to-a-post

"Export" is too abstract. There are thousands of different file formats.
What I assume is happening is that the export script uses evaluated copy of the mesh instead of explicitly applying the modifier. But then instead of using the evaluated mesh's four materials, the script uses the original two. The engine then interprets any overflowing face material indices as 0.
There may be reasons for not using evaluated mesh's materials (they were buggy prior to 3.0), but more likely it's a bug in the exporter and should be reported as such. Adding material slots is a pretty obscure / unexpected modifier behavior.
Now that you've clarified that you specifically meant FBX (you also should update the question with this info), I can confirm that, indeed, the default Blender exporter has the exact bug that I had guessed it might have. Note that alternative unofficial FBX exporters also exist, so you still haven't clarified nearly enough.
You should report the bug to the official bug tracker. In the meantime, here's an extremely dirty fix. Replace the file at \Blender 3.4\3.4\scripts\addons\io_scene_fbx\ with the one provided. It may break other functionality.

Is there a way in Blender to export this part with these materials without applying modifiers?
[Box_1]([Box_2 subtraction colored with their faces] transferred to Box_1)
Just like this: https://i.imgur.com/Sv2XJkW.png
Modifiers are only applied when exporting. Geometry -> Apply modifiers.
Do not commit the part with the booleans, in case it has to be modified in the future. In Maya you do a lot.

Presumably, fixing the exporter would allow you to do just that. You haven't clarified what the exporter or the target engine is. Without fixing the script, your only option as a user is to use "Index-Based" instead of "Transfer" and add material slots manually. It's possible that even simply adding empty slots will do the trick, depends on how the exporter operates under the hood.

I know of 2 ways and the 2 ways don't work. For example, we take FBX. https://i.imgur.com/PnyUZqd.png. https://i.imgur.com/W1Vxn4h.png
They both look like this: https://i.imgur.com/GnM4RIy.png

For example.
Imagine that I have a large object. A house for example. This house has subtractions and each subtracted face has a color, (dining room (floor, ceiling, walls), room (floor, ceiling, walls), hallway (floor, ceiling, walls)...) So that cube matches each subtracted zone it has to have a material type.
So if one day I have to change something I just move the cube (without applying booleans) since these are only applied on export.
It is understood?
Maya does this and that is why Maya is so good. But all good things have mistakes.

The problem is not to paint it a single color, the problem is that Maya has a system similar to UE5 and you can paint every inside face.

I put a screenshot of UE5.
If blender can't do this..
1 - Imagine I have this:
https://i.imgur.com/urUV3co.png
2 - I paint the faces with the material I want (it takes 1 second to drag and drop)
https://i.imgur.com/1gOwR5f.png
https://i.imgur.com/o2OYCwM.png
3 - I can move it at any time
https://i.imgur.com/u5OuGTL.png
The problem with Maya is that it does it mathematically and the faces get lost. EU5 no.

I understand the workflow. Like I said, adding the slots manually, without applying the modifier would have fixed the issue. I have updated the answer with a fix, but you should file a proper bug report.

Solution. You have to add the materials from Box_2 to Box_1. For each slot you have to add them. It's too tedious, but it solves what I was looking for.

write a python script to automate it to make it easy


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"Rounded" extrude from a flat plane?
I downloaded the model of a toe for a 3D Print project as an .stl and imported it.
I am trying to somehow extract the flat part of the model in order to give the toe a more realistic appearance with proportional editing but i wasn't very lucky.
Is there an elegant way to extrude the flat portion to a more rounded "toe-like" shape?

Any ideas, even keywords that I'd have to google are highly appreciated.

You could try to select the center of the toe and then move it outwards with Proportional Editing enabled. But this is a very dense messy mesh, I highly doubt that this will work very good. Another possibility could be to sculpt it...

yeah i would sculpt it. can you share a link of where you downloaded the model if it is free. if not, nevermind.

@HarryMcKenzie not free, unfortunately. Tried scuplting but I'n not very good at it. )-:

well with that type of topology you definitely have to learn how to sculpt. unless you can remesh it.


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Scale works weird with custom orientation
If i move an object using a custom transform orientation axis, everything works correctly. But scale works wrong, scale to 0 using custom X axis can't make object flat. And i can't scale the arm on screenshot correctly. Scale with custom orientation not possible?

Scaling in object mode only affects object-level transformations. Scaling the same object in edit mode will work as expected.
If you look at the object after scaling it in edit mode it should become clear that the same transformation would have been impossible to achieve with just rotation and scale.

One way to do it in object mode is to align the object's origin along the intended orientation.

You can do this without an extra object, by simply rotating the origin point.
If rotating the origin is impossible (e.g. due to armature or constraints), you can instead use a Lattice.

Mesh Deform / Surface Deform modifiers could help with trickier cases, the idea is similar to Lattice.

Thanks a lot for the very detailed explanation! And for showing other ways to do it. This is very helpful!!!


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Dope sheet and graph editor are kind of "dark"
This strange thing happens when some books falls on my keyboard. It doesn't affect to my workflow at all but it's really annoying.
As you can see, it's seems like i have switch off a bright option or something. I can't explain this very good and neither know how to search for a solution.
This only happens on that project. I've tried reseting blender and opening other projects but they looks cool.
Anyone knows the shortcut or the key i missclick or it's other kind of problem?
Thank you

Use "Alt+P" to clear the preview range.


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Strange Offset Keyframe Behavior
Thanks for reading this. I'm working on an animation in 2.8 and am seeing something I've never seen before. It must be a setting I turned on without realizing it.
In the image below, you can see the playback head is on frame 128. However, when I move an armature bone, the keyframe is added to frame 158. I can't understand it for the life of me. I'm used to just making changes and they get recorded where the play head is.

Edit: a clue, if I click on frame 158 with the right mouse button, the playhead moves to frame 128. There's some kind of offset happening...

It was because I was using time remapping on the output options. If "Old" and "New" are set to different values, it creates offsetting behavior with keyframes in the dope sheet and timeline.

Could you be more specific, maybe provide a screenshot? So that people with the same issue will be able to solve it with your answer.  Also, don't forget to "accept" your message as answer via the green check mark on the top left corner.


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How to make quick menu items permanent in 2.8?
When I add items to the quick menu in 2.8, they are lost every time I restart Blender. Any way to make them permanent?
Edit: in addition to the answer below, I discovered that the quick menu keys are different depending on which mode you're in (i.e., Object, Edit, etc...)

yes, i forgot to say that .

go to the edit->user preferences-> and click save(usually this button will be on bottom left.)
i think this will save the settings. so next time you open blender the settings will be loaded.
i hope it work...


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Ambient occlusion bake stops at 0 percent
I am trying to bake textures from high-poly mesh to low-poly. Normals and vertex colors baking right, but ambient occlusion baking resets at 0%. I can see it start baking, but stop after bake of small part, in several seconds after start.  What can be the reason? Here is screenshot of my project:

And a gif, to make it clear:

Ambient occlusion for me usually take a long time to bake. It can be 0% for a while. Just wait

Its not freezing. It just resets, turning off. Like you can see at the picture.

To me baking just finishes its work and turns off. You can see tiny bits of white appearing in the UV islands corners, once it appears around all UV islands baking stops. Probably change AO settings for the scene. Also is there any particular reason to have Bias at 0.001 and Distance at 0? It would be more logical to have the other way around. Note also material in Node editor is for Cycles while active render engine is Internal

authors: Александр Трифонов


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Texture Painting Uv map is gone
My problem is about uv mapping. My model has multi parts. I unwrap my model parts then i create uv map image for every single part. In texture painting mode i painted every uv map image but after paint 3 images first and second is gone.
I clicked first image and it's just show black color not other colors that i painted. I solved this by save as image but i have to do for all uv map images Is there a other way to do this ?

As far as I know, you will have to save these manually every time. Blender will discard everything not used, and not saved. Therefore you will have to save the texture, for it not to vanish.
OR you can pack the image into the blend file.
See this post regarding the same subject:
Why did the texture I painted in texture paint mode disappear?


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Vertex Paint Paint Mask does not work anymore
I'm asking this question again since my first post did not get any answers anymore and my question is still open:
I'm using the current basic steam version of blender and want to use vertex paint with the paint mask feature, so the color stops at the edge of each face and does not " bleed " over to the next faces.
It suddenly stopped working since Blender 3.5
I made a little video directly showing the problem:
https://www.youtube.com/watch?v=HFmBEVjcJ5U
Can you please help me somehow get it working again?
Essentially this:

You have created the color attribute in the Vertex domain but actually, you want to use the Face Corner domain.
With a Vertex color you can only paint the vertices, similar to Weight painting. There is no info stored for the faces.
If you create a Face Corner color then Blender knows which corner of the face you want to colorize. It knows face #5 is defined by vertices #10, #11, #12, and #13, and vertice #10 is green while the other ones are blue for exactly this face.

Note: In the Geometry Nodes spreadsheet, you can check the domains. If you select one you will see the vertices or face corners and their color attribute, respectively.

Thank you a thousand times for your time investment to make that picture and for the explanation. It now works properly :)


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Issues with volumetric fog being too thick
I tried my best to make a fog scene, but when I added volumetric fog it went just a single color. I can't see any objects, but when I zoom in I can barely see the objects.
Scene:

Shader:

I guess the Density value is too high. What does the shader look like?

I've tried with a different mode and it has the exact same issue

link

The Density value (1.000) of the Principled Volume shader node is too high so you cannot see through the fog.
If you want a uniformly dense mist effect, you can simply reduce the value. Try 0.1 or even 0.01. The value depends on the size of your volume cube.
If you want something more like clouds of fog, I recommend using a Noise Texture or Musgrave Texture node for the Density input. For a better clump effect like cloud fog use another Noise Texture for the Vector input.

Finally, use a Map Range node to adjust the final density. Experiment with the From Min and From Max to create holes and clumps. It's similar to a Color Ramp node. The To Min and To Max values define the final density values.
Also try different values for the Anisotropy value of the Principled Volume node for different density and light effects.

Thank you so much!!! I'm ok without the clouds fog too


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Circular progress bar - How to animate from green point to red point?

I want to animate this shape. I want it to animate from green start point to red end point, like there is nothing and then the object will appear from the green point, growing to the red point.

First: there is plenty of animation information on this site to search for and answer your question... try to search before posting.   Answer hint, look at a circular curve to fit the path, and then for the object Constraints, Follow Path of the curve with Follow Curve enabled.  example

As I understand it, the circle is supposed to grow in animation from nothing to a full circle, counterclockwise, starting at the green point. I'm not sure if the Constraints, Follow Path helps here @james_t . I would try it with Geometry Nodes (like the tag of the question suggests ;-). The Trim Curve node can do the animation. I think the challenge is to create the dashed line on it and make it properly growing.

Should the dashes appear one by one or should they grow from nothing to full size? The first case is easy, I think, because you only have to place the cylinders on the points of the curve.

You can do this as suggested with Geometry Nodes.

Add a Curve > Circle (Shift+A) to the scene
rotate it by -90° along the Z-axis so the start and end points are at "the top" (Y-axis) in top view. Then Apply > Rotation (Ctrl+A).
add the following Geometry Nodes modifier (see below)
add keyframes for the Trim Curve > Start value so is goes from 1.0 to 0.0 within 60 frames for examples.
optional: In the Graph Editor, set Channel > Extrapolation Mode to Linear (Shift+E) so that the cylinders all will appear at the same speed.

Geometry Nodes node tree for a round progress bar:

Notes:

the node Transform Geometry with the value Rotation > Z of 5.625d is required to align the gaps on the X-axis and Y-axis. Otherwise, the bars are centered on the axes. The value 5.625d can be entered as 360d/32/2. 360° is the full circle, 32 is the number of bars, and 2 to get it centered.
there is a little flaw: the bars/cylinders at the start and end points are not properly aligned to the curve's normal for some reason. The start point is removed anyway, but if you look closely, you can see that the end point (which is the start of the animation) is tangentially aligned. If it bothers you, you can select them with the Endpoint Selection node and rotate it slightly.
speaking of the tangent, you could replace the Normal + Vector Rotate nodes with a single Curve Tangent node to get the same alignment of the cylinders. (I forgot that there is also this node.)


text:
How do you add extra topology in Blender?
In the following video :
Making a 3D Clownfish in Blender
how was the extra topology added? The part where he says adding in some topology around the 15-seconds mark.

hello, what part of the video are you talking about? Maybe show a screenshot?

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

the part where he says adding in some topology around 15 seconds mark : https://www.youtube.com/watch?v=T5YfWoE_yTk&t=15s

if you are talking about the additional loopcuts it's Ctrl R and MMB or + or - of numpad keys

(The main link in your post is broken, for me) .. The other tool used, (just below the dorsal fin,) is the K topology Knife tool.  If we've managed to help you in the commentary. maybe this post doesn't quite stand up as a question for the archive, and can be closed out? Please let us know how you're doing. Thanks.

At 15 s he is doing a loopcut operation, put your mouse cursor on the edge you want to subdivide and CtrlR, MMB or numpad + and - to add or subtract edge loops. It adds edge loop around the object, as long as it is made of quads:


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Bone is parenting to wrong vertices
My problem is that when I parent my arm object to the arm armature, the middle bone attaches itself to the beginning of the arm, because of that whole thing bends wrong and I don't seem to know what the problem might be
Here is a look at the arm model with armature:

And here is the same model but bent:

For additional context, this arm is a mirror copy of another arm, but the other one does not seem to have this issue
Also here is the blend file:

You should join the armatures together and also join the objects together. Also you need to recalculate the normals as you have some inverted normals (select all the vertices in Edit mode and ShiftN):

The old Inverted normals problem!  I was about to suggest he submit this as a bug when I saw your posting.


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Pose mode question - cannot rotate or scale generated rig controls in viewport - only works in - item - transform panel
I'm having a strange issue that keeps popping up.
I am only able to scale or rotate controls on generated Rigify rig from the item - transform menu. I am unable to rotate or scale any of the controls directly in the viewport (transform works fine). This is true for all controls on the rig...
Any tips would be greatly appreciated!
Thank you so much.
Sincerely,
Jack

here is a link to blender file. thank you for all help!

https://www.dropbox.com/s/i0tdbr0m5nrbrz5/bignoserig1.blend?dl=0

It might be helpful to people trying to help you if you uploaded an example blend file to the site https://blend-exchange.com and add that link in the question.

Thank @RickT will do that next time

You have (probably unintentionally) enabled the Affect Only Locations option. Just uncheck the option and you can use the gizmos again.
The option is hidden in the Pose Options dropdown menu, located in the header of the viewport ...

... and in the first tab of the Properties panel which is called Active Tool and Workspace settings and has a "screwdriver and wrench" icon:

WOW solved! that was it my king!!!!!!  This is my first time ever posting on a forum so surreal. Thank you again!


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empties_to_bones
With Blender 3.4, Windows 11  I have an imported model with some empties that could have been attachment points and I'd like to use them (for building object), I found this plugin but even after installing it it can't show up in the menus and im not sure if it works.
https://github.com/artellblender/empties_to_bones
Can anyone try and tell me if it works? It doesnt work for me

What do you mean, “attachment points”? It is very unclear as to what exactly you’re trying to achieve, so one can’t really say if the add-on works for your purpose or not.

I mean that from the import they could have been part of animation but now I'd like to make them bones as the addon suggests it does. Thats what im trying, once I have them as bones the rest I will deal with. But the menu doesnt show up and I tried 3 versions of Blender

Hi, imc7r, and welcome. This is not really a Blender question.. empties_to_bones is  a third-party add-on, published by Lucas Veber, who has published his contact details here . He has responded relatively recently to  feedback. This question is off-topic, here, sorry. You would be better off contacting the author.

Thanks I will look to contact him

The UI location and how to use the addon is detailed in the addon's repository already: artellblender/empties_to_bones
After installing the addon, you should find its UI in the viewport's sidebar > Tool tab:

Download the .py file and install it in Blender. Select the empties and click Create Armature in the Tool tab.

I don not find the menus after I installed them but as the others suggested maybe will look the answer from the author of the script


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How to simulate bendy antennas/sensors?
I want to simulate the antenna of an insect following the movement of its head, what would be the best way?
I tried simulating using cloth and soft body sims, but its either folding too much or very jiggly. I also thought about bendy bones but then again I would have to place keyframes, which I want to avoid.
This is the result I got with playing around with the cloth sim and a weight map but Im not really satisfied because faster movements will tear it apart.

So is there a way which is ideal for that kind of simulation? Thanks in advance!

This is the file if anyone is interested in the settings beeing used.

There is a free add-on called Wiggle Bones that maybe can help you. Just throwing the tip in here until someone comes whit a proper answer.

It might be helpful to people trying to help you if you uploaded an example blend file to the site https://blend-exchange.com and add that link in the question.

Wiggle Bones would be a good idea, but a Cloth simulation should work fine, it's just a matter of settings

Does this help, at all? .. maybe you've already been there.

The wiggle bones add on looks very promising, thank you guys! The cloth sim could work too I guess but nailing the settings can be difficult and I havent even tried it on a more detailed model, this one was just for testing. Also I added the file if someone is interested in the settings.


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'Import image as planes' Image fading in animation
my image is fading during my animation; how can i prevent this. this is making my animation look vey unrealistic.
https://drive.google.com/file/d/1h2cdI64SwF2_oFxhuQuAnM4VJQG2C61u/view?usp=sharing
this is an image sequence of 6 frames.
► I am referring to the background of trees. in the first image(red circle) the trees are there and as each frame passes to the last frame(red circle) . the image as plane disappears.

There's no way to tell just from that image without more details. https://blender.stackexchange.com/help/how-to-ask

Please look at link: https://drive.google.com/file/d/1h2cdI64SwF2_oFxhuQuAnM4VJQG2C61u/view?usp=sharing

Sorry but 6 frames from a video doesn't help. You will need to show your Blender settings and share the Blend file if anyone is going to be able to help you.

forgive me , it was simply a matter of adjusting "Clip End".
cheers m8,


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can i make a shape follow a line (not as an animation)
I am making an object with a triangular hole in it and I want to know if it is possible for me to just do a circle and somehow have it make a cylinder follow the edge of that hole to make something that looks a bit like a cartoon plunger without me having to make every cylinder by hand and it it is possible how do I do it?

The circle I am talking about in my example is for the diameter of the ring around the edge of the plunger. Basically what I want is, imagine you have pool spaghetti, you know what that is right? The long foam cylinders at most pools. Well, imagine you have one of those. I want to decide the diameter of the circle at each end of it and to have Blender put the edges of the hole at the middle of the circle at the ends of the cylinder and shorten the cylinder to fit on the line.
Steps:

take a cube
cut a triangular hole in the cube
see the edge of the hole
tape a cylinder
make that cylinder clip through the cube until the line/edge of the hole is at the exact middle of the circle that is at each end of the cylinder
make the cylinder the exact same length as the line/edge.

Now I want to be able to just decide the diameter of the cylinder and have it follow the edge/line automatically and exactly rather than having to make it approximatively by hand.

Hello, do you have a reference image?

Please clarify with an illustration of some kind. It's not obvious what a 'cartoon plunger' is.

Thanks for the update. But to me, it's still not clear what you want to do. What do you mean by "do a circle and somehow have it make a cylinder follow the edge of that hole to make something that looks a bit like a cartoon plunger"? Do you want to turn the triangle hole into a cylinder?

the circle i am talking about in my example is for the diameter of the ring around the edge of the plunger. basically what I want is , imagine you have pool spaghetti, you know what that is right? the long foam cylinders at most pools. well imagine you have one of those, I want to decide the diameter of the circle at each end of it and to have blender put the edges of the hole at the middle of the circle at the ends of the cylinder and shorten the cylinder to  fit on the line. i have no idea if that helps or make it more confusing.

I understand the example of the pool noodle with different diameters on each end. But the part with the hole ... do you mean something like this? https://imgur.com/a/f23AAuL

step one take a cube, step two cut a triangular hole in the cube, step three see the edge of the hole, step four tape a cylinder, step five make that cylinder clip through the cube until the line/edge of the hole is at the exact middle of the circle that is at each end of the cylinder, step six make the cylinder the exact same length as the line/edge. now i want to be able to just decide the diameter of the cylinder and have it follow the edge/line automatically and exactly rather then having to make it approximatively by hand.

hello, maybe show a drawing of what you want

i added the picture to my first post, if you don't see it or still don't understand please tell me

So, this is what you want, right? What should the corners look like? And should it be fully procedural/non-destructive or is a manual modeling process ok? Here I've duplicated the edges of the hole, converted it into a curve, and extruded it. It looked bad (squashed, non-uniform scale for some reason). So I used a GN modifier to convert the curve into a mesh. That's what you see in the image. Another try was to use a vertex group + GN modifier. But this didn't work well for the corners. It's not one part but 3 parts, like 3 pool noddles placed together.

The example with the cartoon plunger confused me. You just meant the shape of the handle, right?


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How to get a Blender Obj to render in Adobe Dimension properly?
I would really appreciate any help. New to blender. I am trying to make a 3d model in blender then export as obj to take into Adobe Dimension. I have been trying for days and everything I make that I render in Dimension is black. My guess is the UV on my models. Pre made items like the monkey or far left tube with the top taken off work. but not the 2 center things i made using the circle mesh. Also I noticed the inside of the far left tube is always rendered black on the inside. I can also import other obj from online, add sub surface to smooth and then into dimension and it is fine. Any insight into what I need to change on my model to render correctly would be amazing. Thank you.

Looks like normals issues, your models probably have inverted normals

you can see that the ones that dont work are a different blue/gray colour in the 3D viewport. This means the normals are inverted and need to be flipped (your mesh is inside out). Select the object, go into edit mode, ctrl+F, flip normals and see if that fixes the colour.


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Change Color Associated with Transparency?

ok so here is my problem. in this picture i want the White outside the Blue to be Transparent, and the White inside the Blue to to White.
this is as far as i get when just using the Transparent BSDF.

As you can see, both White areas are Transparent. is there any way that i can make the Outter Area the Only Transparent one??
EDIT 1:
after using cegaton's Advice i set up the nodes and such according to the 4th example,however the full sphere seems to be transparent now, regardless of color placed on the texture.

EDIT 2:
i get the feeling this may just be too advanced for my level of skill in this current time period... perhaps somethin like this might be easier.
In this example im using a stock lightning effect i found off Google. is there any way i can have this so that the black parts are see through, while keeping the rest of the image the same?
FINAL EDIT:
turns out im an idiot and just didnt realize the Alpha channel on the Texture got removed completely some how....quick trip to Gimp and 5 minutes later i got the results i wanted

You change the color input? What exactly are you trying to achieve. Also, if you are trying to make lightning, that is general done with volumetrics/compositing, see https://blender.stackexchange.com/a/28371/3127

The program im making a model for is relatively basic and cant handle much above simple models and textures. And the problem is im trying to use pure white in the model, but when i color anything that way its invisable since that is the color set as the transparency by default by the transparency BSDM.

In that case you will probably want to use an image texture for your lightning.

So is there no way to change the default transparency colour?

What do you mean be default? You can click on the color input and set it to anything you like.

I tried that in the node editor and it didnt work. Changing the setting in the transparency node just changes the base color of the object. Im at work right now but when i get home ill upload some pictures of what in trying to explain.

If you are exporting this to another program why are you worrying about node colors? Those will most likely be discarded anyway

ill be honest im new to blender, so i dont know terms or phrases very well, im probably using most of my words wrong here... i cant seem to find the correct way of describing the effect im trying to get


text:
Loopcut in a script
I'm a beginner in Blender and I want to do a loopcut in a script, and I saw that it was possible only in 3D view.
Is that why this command doesn't work?
bpy.ops.mesh.loopcut_slide(MESH_OT_loopcut={"number_cuts":1,
                                            "smoothness":0,
                                            "falloff":'INVERSE_SQUARE',
                                            "edge_index":81,
                                            "mesh_select_mode_init":(False, True, False)},
                           TRANSFORM_OT_edge_slide={"value":-0.25,
                                            "single_side":False,
                                            "use_even":False,
                                            "flipped":False,
                                            "use_clamp":True,
                                            "mirror":False,
                                            "snap":False,
                                            "snap_target":'CLOSEST',
                                            "snap_point":(0, 0, 0),
                                            "snap_align":False,
                                            "snap_normal":(0, 0, 0),
                                            "correct_uv":True,
                                            "release_confirm":False,
                                            "use_accurate":False})

Is there someone who has a solution to by-pass this problem?
PS: Sorry for my bad english, I'm french

You'll need to pass a custom context override as a positional argument:
bpy.ops.mesh.loopcut_slide(override, MESH_OT_loopcut={"number_cuts":1, ...}, TRANSFORM_OT_edge_slide={"value":-0.25, ...})

The override can be defined as follows:
window        = bpy.context.window
screen        = window.screen
view_3d_areas = [area for area in screen.areas if area.type == 'VIEW_3D']
regions       = [region for region in view_3d_areas[0].regions if region.type == 'WINDOW']
scene         = bpy.context.scene

override = {'window':window,
            'screen':screen,
            'area'  :view_3d_areas[0],
            'region':regions[0],
            'scene' :scene,
            'edit_object':scene.objects.active
            }

Also note that the active object needs to be of type MESH and in edit-mode. You can check for this with the following code:
active_obj = bpy.context.scene.objects.active
if active_obj.type != "MESH":
    # alert user that active object must be of type 'MESH'
if active_obj.mode != "EDIT":
    # alert user that active object is not in edit mode