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Best way of connecting two meshes, one with many faces
I am trying to model a gas mask. I've made three separate meshes and planned on attaching them to the main head mesh. Those three comprise of the two lenses and frontal gas mask filter. But I've run into a problem with that.
I'm unsure of the best of attaching a mesh with many faces to another mesh with less faces. I don't know what the most efficient way of doing this would be.

as explained by Lukasz-40sth, to join all these objects and make only one object, press ctrl J. Now you can work your topology to make only one mesh but are you sure this is necessary? In reality these 4 parts are separate objects so you it would be logical to keep the meshes apart.

A typical subdivision approach would avoid using meshes of different densities where possible, and rely on Catmull-Clark subdivision to create curvatures/circles..
Any (6+)-gon will make a reasonable circle under subdiv. Often made from 4 quads:

Select all quads
CtrlX Dissolve central vertex
AltP Poke single face
-CtrlShiftB Bevel central vertex
Shipped Add-On, Loop Tools > Circle the result

Then, with extrusions, and some rotations/scales around Custom Orientations, you can model something like this mask without having to reduce topology to match between densities.

If you do really need to match areas of significantly different detail, often, to avoid fiddly hand work, you can model at a lower level of subdivision than your intended result, apply one level of subdiv, and continue modeling from there.

..and as moonboots and Lukasz  have said, unless you have constraints such as 3D printing, separate parts are usually best modeled as separate parts. No harm.

With separate objects as described by you the best way is CTRL+J or Combine. Provided that all your objects are modelled as you want them. Other ways require heavy retopologizing.


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Can only Extrude or move vertices/edges in a pre-set distance
I just started using blender yesterday to model a character. I got through most of the head but now, every time I want to move vertices/edges or extrude, I cannot do it properly. If I try, it moves at a pre-set length that I can't seem to get away from. Please help!
You can see the file here (http://s000.tinyupload.com/?file_id=61829621657266848046)

Sorry for the duplication, I had no idea what this was called..

source: Stack Exchange

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

sort: votes


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Problem with tree render
I'm newbie and tried to do a tree in blender, basing on YT tutorials. Unfortunately, it's looks like most of leaves disappear, when i render it, while the rest, are completely dark. In object-mode view, all leaves are normally visible. What is the cause?

Could you post a screenshot of the 3d view and the eventual particle system settings? Could you also add the link to the tutorials you mentioned or describe the workflow you followed? (there are many ways to build a tree)

I based on this: 1. Here is screenshot 3Dview. I didn't do anything with particles systems.
When I turn on "texture view" in Object mode all leaves go dark, despite that in material preview, texture is green.

It could be that your leaves aren't unwrapped, they won't use texture and material settings in that case. Check if unwrapping was done and examine how does UV map look like.

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


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Blender Hair System uses different seed on different computers
I am trying to render a pretty complex hair setup on our local network of workstations with cycles X. I use 3.0.0. The machines all render to our production server with placeholders. Works fine normally.
The problem is that, apparently, the hair systems use a seed specific to each machine. That's a problem, since they are jittering and jumping around, when seen in sequence.
The hair systems are simple, non-dynamic setups. So i can't bake a Cache. Converting is also not an option, since it's millions of hairs.
Is there any way to fix this? I saw a few threads about this from 2017, but I recon stuff has changed since then.
Thanks in advance!

Hi :). Which threads have you read/tried? The particle system hasn't changed in a looong time, so older solutions could still work ;)

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


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Blender randomly loses environment texture
I frequently run into a very annoying problem when rendering scenes with cycles where I use an environment texture.
Upon rendering the animation, Blender sometimes looses the environment texture, displays it as pink and renders the whole frame unusable. The render then stops, I have to manually save, close, restart the program and continue rendering. It happens about 3-4 times in 300 frames during a 6 hour rendertime.
It happens on both CPU and GPU renderers and happens on different computers, even different users (a friend of mine has the same problem). The problem occurs in Blender 2.76 and 2.77.
The GPU renderer outputs this error message: cuda error at cumoduleload: file not found
I tried relocating the texture to a SSD, a different HDD, the projects directory, nothing helps.
Any ideas? Thanks for the help :)

Same Probleme. Not always but often when  i use  a .dds  texture.

If this happens in different computers or under different users you may have encountered a bug in the software or have a corrupt file. Is this happening while rendering from the same file, or is your friend experiencing the same in a different .blend file or the same texture? If so this may be worth reporting to the bug tracker.

I run into this issue all the time, mostly when using scenes that have DDS files as textures.  No idea what the issue is, but I use a workaround to avoid it.
If you run it from the command line with a limited number of frames per run, you can do the whole run without worrying about getting the pink textures.  For example, the following series of commands will render frames 640 through 669, in 3 batches of 10 frames each.  By using the #### format in the render output, it will automatically put the frame number into the filename.  That way you can get a nice image sequences without running into the texture issue.
blender --background intro_scene.blend --engine CYCLES --render-output //tmp/HM-####.png  -s 640 -e 649 -a
blender --background intro_scene.blend --engine CYCLES --render-output //tmp/HM-####.png  -s 650 -e 659 -a
blender --background intro_scene.blend --engine CYCLES --render-output //tmp/HM-####.png  -s 660 -e 669 -a

No idea why it does this in the first place.  It's really frustrating.  Here's the full error for anyone who wants to dig into it a bit more:
Failed loading CUDA kernel C:\Program Files\Blender Foundation\Blender\2.79\scripts\addons\cycles\lib/filter_sm_52.cubin.
Error: CUDA error at cuModuleLoad: File not found


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"Transparency Clipping" when working with multiple transparent objects
Unsure how to describe this. I am currently working on a particle cannon effect with a core and 3 lightning "tubes" around it. Take a look:
First, The elements:

The inner core is a simple cylinder, distorted by a noise texture. I made sure that there is no clipping in the mesh.
If rendered by themselves, as seen in this first picture, there is no issue.
The Material for the core:

The Material for the Lightning bolts

When you render them together...

It appears, that as soon as two or more of the "creases" of the inner core overlap, the tubes that should be transparent get rendered.
Is there any possibility to "increase" the threshold or otherwise solve this problem?
Thanks for any help!

Changing the render settings does not help. I tried every setting possible.
Edit: No I didn't. That helped. Thanks!

Potentially related: http://blender.stackexchange.com/questions/18857/how-to-eliminate-cycles-artifacts-with-many-overlapping-volumes

That did it! Thank you very much! Feeling stupid now haha.


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Trouble smoothing a curve
Issue that I'm having is that I'm trying to round off / bevel smooth the hard edges on this object. Have been watching some videos and reading on different smoothing and beveling techniques but not having any success so far.
What I'm trying to get is a similar profile to what you would find on most eye glasses legs where the edges are smoothed out so as not to bug the wearer.

I can kind of bevel the straight edges of the object ok with the boolean tool or modifier, but they keep getting hung up on that section I cut out.
Here's an example using the boolean modifier:

Here's an example of using subdivision:

If I use the bevel tool in edit mode, the edges get a little smoothing but not to any great effect:

You need to apply your scale (CTRL-A) With your scales that wild the bevel modifier will give bad results. You've definitely got something weird with the curved part. Maybe it is not connected properly? Have you done Merge by Distance of all verts?

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

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


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Advice on modeling stereographic projections?
Hoping to get some advice on modeling stereographic projections. I found a pretty manual process but it doesn't hold up if the model gets too complicated. To clarify, I'm working with meshes because this is ultimately meant to be a printable model. Doing texture mapping isn't the end goal.
For reference, I'm talking about these kinds of objects https://www.thingiverse.com/search?q=Stereographic+projection&type=things&sort=relevant.

These are the my manual steps:
Issues I'm having
The process I describe below works, but its not ideal. Its processing lots and lots of mesh intersections so its really slow and anything more complicated than a simple grid just breaks down. Blender crashes, basically.
End goal
It seems there should be a way to simply project a mesh onto a UV sphere. Some process that will allow much more complicated mesh designs to be used.
I've tried combinations of shrinkwrap, simple deforms, casts, surface deforms, and some other things but nothing is quite working. So far using a cast kind of almost works, but its widely distorted.
My current manual process (poor man's version)
What I have now is creating a mesh grid first.

Then I extrude the grid and scale it to a point. I then select and merge all of the vertices at the point.

I then create a UV sphere, add a boolean intersect on the sphere with the extruded grid, then apply that.

Lastly I delete the resulting top vertex from the modified sphere which leaves me the mesh of the intersection.

And finally, I can get this after adding a light source (final product):

This process works but is nowhere near ideal. If I make the grid mesh any more detailed, or try to make the sphere smoother Blender can't keep up and takes forever or crashes.
I've looked all over and but the only information I've found is about projecting textures, using 2 simple deform modifiers (which doesn't give me the result I'm going for), or a 5+ year old python script that has never been updated.
Anyone have some ideas about how to do this efficiently?

Method 1: Halfway there but easy
You could kinda solve this by adding a shrinkwrap modifier to the plane with your design. Set "Wrap Method" to "Tangent Normal Project" and set the "Target" to a sphere sitting on top of the plane. The projection is correct, but this only gives you half a sphere.

Method 2: Use Geometry Nodes! (I used Blender 3.2)
The Final Boss method of doing this is to use Geometry Nodes.
Using trigonometry (see here https://www.omnicalculator.com/math/triangle-angle for all triangle equations), you can calculate an offset vector for each point towards the light source, such that it falls on a circle of radius r.
Step 1. Calculate angle between light source and a Point
You know the light source location, and you know the location of each point on the plane. Using the formula Beta = arctan(x/h), Calculate angle Beta shown below. You can also calculate the hypotenuse d using Pythagoras theorem a^2 + b^2 = c^2.

Step 2. Calculate the offset distance from the light source to the sphere perimeter
We now have ingredients for a new triangle: 2 sides and an angle. One side is the sphere's radius. Another side is the light's height minus the radius. The third side, which we want, is the offset distance between the light and the sphere perimeter.

Here is an excerpt from omnicalculator on how to calculate the third side:

Step 3. Calculate an offset vector to shift each point towards the light source so it lands on the sphere's edge
Finally, if we have a vector between each point and the light source, we can scale this vector by 1 - c/d and use this as an offset in the Set Position node of geometry nodes. We will end up warping our plane mesh into a sphere with a perfect projection.
Node Tree
This is the node tree I used. You can use your own plane design, and replace my grid generator in the node tree with your own geometry.
Here is the node tree:

Blend file - have fun with it!:


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Automated way to find the center line of a 2d mesh?
Given the simple 2d mesh pictured below, is there an automated way to create a curve or line that follows the middle of the mesh? I am able to do this manually with a bezier curve, but it would be helpful if there was an automatic way to do it for better precision.

Example of what I'm thinking (made by hand with a bezier curve):


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Possible to use geometry node on a selection of vertices on a model?
Is it possible to apply a geometry node to a selection of vertices on a model?
Basically I have a model where in certain areas I want to increase the subdivision count to get more details from a displacement modifier, but I don't want to increase the subdivision count for the entire thing.
I have an alternate workflow where I can apply the subdivision surface node to individual pieces, then join the separate geometries later. But if possible I'd like to avoid complicating the final assembly of model parts. This ultimately is all manifold and ready for 3d printing.

you can't subdivide just part of the mesh with geometry nodes, I mean, you can easily select and separate some geometry, subdivide it and join again, but you will get non manifold edges...

@alambre yeah that's what I was thinking was going to happen.

depending on the mesh you could try to fix this inside nodes, picking the edge, merging every 2 or 4 verts and then joining with the rest of geometry... not easy but could work for some topologies I think

A different (also not very elegant) way of doing it would be if you select the faces which should have a higher resolution, then subdivide them in Edit Mode. This way the selection has a higher basic resolution, so the Subdivision Surface increases this even more.

As a workaround, this is how I would do it... this way there's even a slight transition from lower resolution to higher resolution:

Select a part of the mesh which should be subdivided more than the rest, right-click and choose Subdivide.

Then I select a little less by pressing Ctrl+Num - and subdivide it again.

And then I do that once again so the end result looks like this:

Now I add a Subdivision Surface modifier to increase the resolution even more and add a Displacement modifier afterwards, so the object has areas of differently high detailed displacement.


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Help with non-manifold geometry and stl file
Pretty new to Blender and modeling in general and I've spent a couple days trying to figure out this problem. Can someone more knowledgeable take a look and give me some direction?
Background
Been working on modifying a 3d model in preparation to print, but have been running into what's become an insurmountable problem for me.
I've divided the model up into sections and added keys to help printing and assembly later. Have then exported each section as individual stl files to test importing and slicing in the print utility. All of the parts are fine except for one.
Issue
The problem section seems to have some geometry issues that I haven't been able to fix. There appear to be some non-manifold sections but I haven't been able to find a way to fix them. Have spent hours tinkering with the model manually to no avail. I've ran the section through Mesh -> Cleanup, as well as trying to apply a combo of remesh and decimate modifiers. (The last 2 kept crashing Blender so couldn't make progress that way.)
The key hole on the bottom may be causing problems. The stl file that gets generated sometimes has errors in the slicer or completely disappears when I change the rotation of the section model.
Here's an image of the non-manifold sections selected.

Here's a link to the blend file of the model https://drive.google.com/file/d/1ESKfCxDuTgUELPmL98NK5f8HZFfpfKw9/view?usp=sharing.
In the blend file, each model section is labeled like "sword-0", "sword-1", etc. The problem section is "sword-0" and should be the only one visible on opening the file.

Hello :). The non-manifold parts are technically easy to repair, but it's rather hard to explain :). The main issue are faces going through other faces, and simple holes (you probably just forgot to fill them)

I repaired the mesh, and uploaded it here on GDrive so you can check it against the old one. I also included a version with a Mirror Modifier, so you can better see the final geometry.

Since your mesh contained many examples of non-manifold geometry, be sure to check out what it is and how to avoid it :). You can start here: What is non-manifold geometry?.

@JachymMichal you're my f-ing hero right now. Man I wish I could watch how you fixed the mesh. I'd learn a lot from that. How did you get the large side faces to intersect the curved parts so the large face didn't continue behind curves?

Hey, np :). I'll add an answer with some examples of what I did. The file also contains the repaired mesh with a Mirror Modifier - if you disable the modifier, you can see the topology more clearly.

@Geuis BTW, there's a tool called Mesh Mixer which can auto-fix non-manifold geometry in an STL file. Here's a video describing how to use it to fix a mesh for 3D printing.

There were three main issues with you non-manifold mesh:

Faces going through other faces - You need to reconnect them vertex to vertex.
Disconnected edges (with gaps) - hard to notice, check for non-manifold vertices
Holes in mesh - just fill them through Vertex > New Face (F)

To check for non-manifold geometry try this:

Select > All by trait > Non-Manifold. This will highlight all non-manifold vertices. There should be none.
Check face orientation - this will also reveal small holes and missing faces

Faces going through other faces

Disconnected edges (with gaps)

Thanks for gifs. I think I see what you did. Really appreciate this.

Glad to be of help :). Good luck with your project.

Hey @JachymMichal, one other question. How did  you turn the model blue in the updated file? I haven't been able to figure out how to set it back to grey.

Sure :). That's Face orientation, check my answer, there's a link :).


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Texture Painting is not working on ONE file only, other files work fine
I'm currently using Blender 2.8
In the file i'm working on, i unwrapped a mesh (Smart UV Project) -> Add base color in the "Texture Slot", but then i am unable to paint over it.

Therefore, i tried creating a sphere in the same file and try texture painting it, it doesn't work as well.

So i created a new file and try that again, it works. Can anyone explain why Texture painting works fine in other files but not this particular one?
I am new to Blender so any help from you guys is very much appreciated!!

I found the solution. Maybe it is a bug that is causing the problem or i may have done something wrong, but you can fix it by just copying whole mesh to new file. And it works!


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Texture paint showing a random old render on my model
See the following screenshot.
I am trying to paint my model but some random artifacts are showing up on my model and makes it hard to see what I'm painting exactly.
Deleting my models texture, UV map and material does NOT solve it.
I also tried restarting it obviously but without luck.

Have you tried appending the model to a new file and seeing if the same thing happens again? I cannot see anything wrong in the screenshot that woudl explain the weirdness.

.blend would be helpful, with packed textures. https://blend-exchange.giantcowfilms.com/ or http://pasteall.org/blend/

I think you need to look to see if you have your old render as a brush texture.

Hi, thanks for the quick reply. But this is not the issue. The artifacts appeared before I even painted and nothing is set as a brush texture.

Please consider appending to a new file or uploading a file for us to look at then.


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See-through jelly like substance shader
I'm trying to recreate the little red balls on top of the gunkan sushi. So far I have this. Just a glass shader with a translucent shader added on top. I don't know if this makes any sense but if it doesn't please fill me in. Also ignore the rest of the render since it's obviously not final and just a test render.
Looking forward to your answers!

Probably worth looking at sub-surface scattering for both the roe and the cucumber.

Hi, thanks for your reply. How can I can make it reflective like the ones in the photo with SSS on?

I am not that experienced, but there are tutorials on the web (try BlenderGuru as an example) that can go through the basics. Even though you have accepted the answer below, a good learning exercise would be to compare SSS to the glass shader to see the visual differences (maybe even combining the two approaches.

I tried SSS at first but was not happy with the results. I decided a glass shader looks much better.
I just used a Principled shader with transmission set to 1, for glass. Then I added some volume scatter with a slight orange color just so it doesn't look like glass and has some volume in the inside.
I did not do it here but I think slightly deforming the spheres will give it some more realism.

Thank you so much for your reply. I never really looked at volume scatter this way. I'll try it as soon as I can.


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How to model a flial?
How can I rotate them correctly? I want it with a patricle system so i can quickly add more spikes if needed

In the Properties panel > Particles, enable the Advanced option, then activate the Rotation option and choose Normal in the Initial Rotation dropdown menu. If you enable the Scale and Rotation option under Render, the scale and rotation of the peak object in the global scene will be reproduced, it can be handy.

Ohh nice trick with the object rotation. thanks for the quick and good reply!


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How can I turn off the display for these orange dots on my hair particles?

Changing the particle select and display modes won't solve it.
The orange dots just keep floating in air when I comb the hair.

Deselect "Children" from the left-hand menu under "Draw".

Thanks, what's the purpose of those orange dots tho?

If you had child particles in the hair simulation (particles tab -> children), you would see the child particles displayed there. Since you have none, they are just empty vertices that are stuck in place. Child particles are sort of a "virtual" particle thats controlled by a "real" one in a way specified in the Child Particles tab. This allows for a lot denser hair, without all the physics calculations that would go into simulating millions of particles (since only like a thousand strands control the movement of the million particles).


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Blender 2.8 volume over transparent background not showing in rendered image
I made this planet with a volumetric shader for the atmosphere

Left you see the atmosphere rendered in viewport mode
Right you see it just rendered out but now the volumetrics are missing
Any guesses?

Thanks guys for the fast reply. This was the problem indeed. hope they ever fix it, thanks :)


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Tinted glass for a helmet
I have this character with a helmet.
I want to see his face clearly through the glass and see clear reflections from the environment
I also want it to have an orange tint.
something like this:
Clear see through glass, clear reflections

And tinted color

This is how far I came:
I tried shader with glass and shader with transparant and glossy combined with a diffuse shader.
With a HDR and a sun lamp.
Not really reflective maybe?

Kinda better I guess but a little dark and now has double reflections?

With this shader:
How to illuminate the darkness inside glass objects in Cycles?
And volume aborbtion but still double reflection?

I appreciate any help

Thanks for the reply. I copied the shader and it looks pretty good but i still have 2 reflections even though the object isnt that thick. And if i dont give it thickness its working like a lens. any thoughts?

I agree but why is the distnace now greater? In the other render it was closer together now it's distance looks doubled. Also I don't see a double reflection in the first reference image. Now I'm just curious :)


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About clothes for a High to Low Poly pipeline
I need clarification since I've done a high to low poly process before but now there's a new problem that complicates things for me slightly.
How I would do a character is make the high poly with all the details (clothes included) and then retopologize it, clothes included, as one full mesh. Then with the retopologized mesh, I'd bake a normal of the high poly.
But the problem is that this works only for one costume of this character.
Now I'm thinking of a different pipeline for interchangeable clothes. So it'd be the same character. I'd do the high poly of the naked character. But then I'd also need to do clothes over this high poly naked base mesh. That leads me to--

How do I sculpt the high polys and do retopos of clothes over a naked character?
What is the UV mapping process considering it's no longer just one mesh but several different ones like the head, hat, shirt, pants, boots, etc. ?
I'd like it to be possible to iterate or add new clothes whenever a new idea comes up or if problems arise.

Sorry for the noobish question. I've found several low to high poly workflows but not for high to low. Let me know if there's any other solutions or if my reasoning is incorrect. Thank anyone for their times for helping.

I think I dont follow quite well. You want to retopo a hi-poly mesh to a low-poly one but before use the character as a "collision" object when sculpting to prefent the dress go-thru???

I want to make a high poly mesh for a character as a "naked" mesh. Then I want to also have other high poly meshes around that mesh (Clothes, hat, etc.) before retopologizing all those separate objects. How would I go about that?

You want to make that clothes on the naked mesh (using its shapes) or just around it? Probably the easiest way to make clothes in Blender is using part of the source mesh (ie naked) and make tweaks needed or build the basic shape, fill with (a LOT of) polys and use the Shrinkwrap modifier. Check this for 2nd method: https://www.youtube.com/watch?v=szEeu6_b4fg

Yes, I'd like to put the clothes around it, so as to be able to customize and change from one shirt to another, for example. Also, interesting video, it looks like a quick way to do clothes from what I briefly saw.

The important info I need is will You use the base-mesh (naked) during the modeling of the clothes?. If the answer is YES then use the Shrinkwrap, if NO then use standard techniques.

Yup! I think Shrinkwrap/ what the video you linked is exactly what I'd like to do. Thank you.

You are quite welcome Near! Watch this: https://www.youtube.com/watch?v=9zNAATDadJc ...and happy Blending!!!


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Why are my low-poly models rendering smoothly?
Sorry about the probably silly question, in advance.
This is my first time using blender, and I want to get into low-poly stuff, which has been great so far! I managed to make a cat and that went pretty well.
I thought I'd make some trees next. However! Everything was going well until I rendered the models. The "rendered" viewport shading mode brought the result I was looking for (below).

Yet, when I properly rendered the models, they appeared rounded.

Did I click something accidentally? Thank you so much!

Remove subsurf modifier from the modifier tab or if u still not getting attach the file here https://blend-exchange.giantcowfilms.com/

Thank you! Resolved, I somehow had my render subdivisions (?) set to 2.


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How can I create an animation with a transparent background in the Material viewport?
Sorry if this is a repeat. I've had a lot of trouble explaining or putting this into words.
Basically, I want to make an animation with a transparent background, but I want it to render with the appearance of the Material Viewport.
I've been told that OpenGL is the best way to go about this, but I can't find any options for transparency in cycles for OpenGL.
I was able to create a transparent background in the typical Rendered view, but not in OpenGL. If there's a way I can replicate the "Material" appearance in the default rendered view, that also works!
Thank you so so so much in advance, this has had me puzzled!

try setting "transparent" in the top-bar "render > opengl render options > alpha mode", you should get what you want... (default is "sky")

nice :) btw if you use viewport rendering, it is not cycles, nor blender render. just pure opengl, whatever shading the viewport has.

There are three ways to render images or animations with a transparent background.
Using OpenGL render :
Make sure that you set the Alpha mode to Transparent in the Render > OpenGL Render Options > Alpha Mode which is located in the info header.

Using Blender Render :
Make sure that you have set the Alpha to Transparent in the Shading option under the Render tab in the Properties panel.

Using Cycles render :
Make sure that you the Transparency ticked on in the Film option under the Render tab.


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Edge Gap in Shadow Catcher Material Masking Blender Eevee
so I'm trying to render an object with shadow, since eevee doesnt have shadow catcher, (blender 36.2) I use "material shadow catcher", then separate the render in two layer (the object & shadow), the problem I encounter shows that there is a gap between the object and the shadow (I use photoshop to merge those layer), anyone know how to fix this? thx


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Bones rotate outside of mesh
So when i rotate the bones sometimes it leaves the mesh instead of staying inside.
any suggestions?

in Weight Paint mode, make sure that your bone weigh on your mesh

I Checked weight paint, it looks pretty good. the mesh moves with the bone but hardly.

Another bone must influence this part of the mesh so you should remive it from any group then assign it to this bone again


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How can I straighten a bunch of vertices into a straight line? (Odd angle)
As you can see on the Top Ortho view, the selected vertices are a bit of a mess, and I need them to be perfectly aligned like the green line I draw next to them, while keeping the same, circle-ish shape.
How can I go about it?
I tried a few methods posted on this site and elesewhere but I never managed to make it the way I want it.
I would also prefer avoiding redoing the complete thing over again.
Thanks

This might work for you. Enable LoopTools in preferences then select the faces concerned rather than the vertices. Press W, choose "LoopTools", choose "Flatten".

Thanks a lot, that was it. Upvoted and accepted answer.


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Should I Join or Parent?
I am making a battleship, and there are many tiny cylinders and cubes for detail. Because the only things that needs to be animated are the turrets, should I join all idle parts together?

yes why not, you can make a big bone for the whole thing, then small children bones for the turrets

remember that you can always use Separate - Loose Parts to get back from a Join

It's not brutally important when you have a limited amount of parts.
Blender 2.79 is still not amazing at handling many 1000s of objects, so sometimes joining can speed selection up quite a bit.
But there is one thing to think about:
If your detail objects make up a lot of verts, I wouldn't put them into the hull but their own object. That way you can, to speed up test rendering, switch them off and keep the hull.
Depending on complexity, that can make a difference.
Another aspect: you can parent objects to faces. Not too relevant here but if you have an object that might change later, parenting the details to a face means you can change the height of a floor and the objects will follow.
If it's all geometry, you either have to select all tiny meshes or abuse a vertex group for selection purposes.
Yet another aspect: Object origins make for great rotation centers. If it's a mesh, you either need a used or hidden center vertex or you have to select the right verts to place the cursor.
My advise here? Save a backup copy of the unjoined objects, join the details into one or a few objects (bow, midship, stern etc) and parent those to the hull.


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"edit" a bone in pose mode
I have a robotic arm-crane like machine. It has an IK set up so when I move the end everything else moves. But I want there to be an extendable arm that will "edit the length of the long bone. Is there any possible way to do this?

You can use a transform constraint on the extendable arm bone to turn the control's movement into scaling.
You will want something like the following settings:

You only care about translation on the bone's Y axis, so local space and only a y range. The size of the range specified for location (i.e. the Max position) controls how rapidly the control will move the upper part of the telescoping arm.
unused scales should be 1 -1 ranges not 0, or things can disappear.
scale in local Y space again, along the bone's axis. Scale minimum will need to be tweaked for the appropriate rest position.

As you are scaling the bone this can get inherited by child bones, which you don't want, so make sure that for all the children you uncheck the inherit scale option in the relations section:

Depending on how you are attaching your model to the mesh, you may wish to add two child bones to the extending arm to position each part. The lower part can have a copy rotation to the scaling bone, and the upper part can be parented to the scaling bone. In my blend file I have added two smaller bones derived from the main arm are just there to define the position of the two parts or the arm in the armature. This can be useful if you want to rig other parts that need that information, and allows you to use an armature modifier and vertex weights if you need to export to a game engine.
Example blend:
https://drive.google.com/file/d/1Ee_ZH70Mk4e2HfVfx3BCoHiKV6tqwcc_/view?usp=sharing

Apparently blend-exchange is giving me an error, so shared on g drive for now.

This is what I want, But I'm a bit confused as to what the two smaller bones are far, and it seems as if there's more to what you wrote according to the file.

@caleblee the two smaller bones derived from the big ones are just there to define the position of the two parts in the armature. This can be useful if you want to rig other parts that need that information, and allows you to use an armature modifier and vertex weights if you need to export to a game engine.

Wow this works great! Just one more thing that you don't really have to answer: Right now it's hard to move it precisely because the movement are so quick and sudden. Is there a way so that you have to move the control bone say twice as much to pull the upper telescope?

@caleblee If you want a bigger range of input, just change the max location in the transform constraint


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Blender 2.8 Front and Back Background Images
I have two reference images, one for the front and one for the back. I want the images to be slightly transparent, but then I will see both images which will be confusing. How would I make it so that an image only shows up when I'm in front view, and the other only shows up when I'm in the back view?

In Blender 2.8, background is an object.

select one of viewpoint (if you skip this step, the background is always visible regardless of viewport angle)
type Shift-A, and select Image → Background
select an image file

Then, you'll get an object with image. The object has settings for transparency and side, which you want.
So, add two background objects that way, and set the side to Front for one, and to Back for the other.


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Will excessive rendering damage a GPU?
Whenever I head to school or somewhere else, I sometimes like to render my images(even if they're not complete) at something crazy, like 10,000 samples at a high resolution with many light bounces. Will this damage my computer or GPU, or take up space?

If your computer has proper cooling and therefore doesn't overheat, it won't damage the GPU.
It will have an unfavorable impact on your electricity bill and carbon footprint though.
Whether a sample size that high is actually appropriate is another question. You probably don't need that many samples or there are computationally less expensive solutions to reduce noise, e.g. the denoiser.
The rendered image will take up disk space when you save it. How much it will use depends on the resolution, the image format and its settings. The higher the resolution, the larger the file. For an overview of image formats and their disk space usage, take a look at the last section of this answer.

You're not going to "damage" your GPU. What may happen is that if it is constantly over-clocked or over-used, it may wear out faster than a less-used GPU. Render however you wish, as long as your GPU can handle the amount of processing you're asking of it, then it will be fine. However, 10k samples does seem very excessive.


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Striped Shadows on EEVEE
When my camera is looking at a surface at an angle, the shadows begin to look stripped. I have tried changing shadow settings but that has not helped. The stripped shadows have also appeared when I render in EEVEE too. Is there any way I can minimize or remove these?

I have a hunch that your object might be too big.

I have tried scaling it down but it didn't help

After I updated to Blender 2.81.1, It fixed the problem. Earlier I was using 2.80.

I was answering my own question and this worked


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Have 2 objects act like one
I have an apple that is thrown into the air and then sliced in half. Because of this, there are two different objects (the halves of the apple). When it is thrown, I want to use a Rigidbody to get more realistic physics. How can I make the two halves act like one object for a certain amount of time?

I would do the animation of the single apple first and then swap out/in the two halves. You can do this by animating the Rigid Bodies Dynamic toggle and moving anything in and out of view in a single frame.

If I do that, you will still see the object fly in because of motion blur, which I want to keep on.

Try giving both pieces the same origin, and parent one to the other using the "child of" constraint. Animate it's effect off once it needs to fall away from the other piece.

How would I give the object with the constraint a rigidbody?

You would give it a rigid body in the physics settings, and set it as "animated" (as opposed to dynamic) and keyframe that off at the same time you take the constraint off. Let me know if that works for you!

Ahh, turning off dynamic was what I was missing. Thank you :)

Yikes, the half without the constraint  is getting "pushed" by the other half and it's doing weird things. Is there any way around this?

Has the collision shape been set to mesh? (in rigid body settings)

Yes but even with mesh their is a tiny margin and my objects are perfectly touching to create a seamless look. If I set the margin to 0, it won't work proprely either

what if you made two apples- one whole one, and one that was cut. The first one flies up into the air, and then you keyframe off it's render visibility at the same time as you keyframe on the visibility of the cut one. The pieces could come apart and it would look right (probably.) Is that at all helpful? :)

It shouldn't affect your motion blur either.

Ok, but other fruits are being thrown and the invisible apple still has a rigid body which is interfering with the other fruits. How can I also turn off the collision?

Try placing each individual fruit setup in a collection and adjusting the rigid body settings to only interact with that collection.

Wow! I was not aware that you could have collision collections. This works perfectly, thank you.

You are welcome. I hope you achieve what you are looking for!


text:
Start a particle’s animation when it’s in a certain location with animation nodes?
That title is quite the mouthful, so I’ll try to explain my issue as best I can, which I had for like 5 days now and simply can’t find any solution to.
Context:
I have a plain that is subdivided a bunch of times, and is being warped from point A to B (not really important where, just from one place to another) with a warp modifier. I have a hair type particle applied to this plane, and the particle itself is an instanced object that is rigged with an armature, and is animated from frame 1-80 on the timeline.
Issue:
The problem is that on the plane, all the particles animate at the exact same time from frame 1-80, which is not what I want.
Desired result:
What I actually want to happen is that the particles should animate when they’ve been warped to point B. This of course means that when it’s warped, the particle is in a different xyz coordinate, which I’ve read can be used to trigger the animation of the particle using animation nodes. (specifically I’ve read it here, which I’m not exactly sure is still useful info considering that thread is over 8 years old) So for example’s sake, let’s say when the Y coordinate of the particle is 0<= then start the animation.
Now I’m completely new to animation nodes, I just installed the addon, and watched some pretty basic tutorials on it. So I have absolutely no idea how to accomplish this task. I'm not sure AN is even needed to achieve what I want, but from the dozens of threads I've gone through, it seem it's my only option. So if you can help with this, or perhaps have any other idea on how to achieve this result with other methods, I’d be very grateful for any help!
Thanks!

Not sure if this will be helpful, but I had a similar project where I was trying to animate a crowd of simple stick figures, but wanted them to be in different parts of their walk cycle so they didn't look like they were marching.
In my case, rather than rigging, I used shapekeys to animate the characters, used particles to instance the objects (as you're doing,) then had animation nodes cycle through the shapekey animation based on the overall animation frame #, but assign a unique offset value for each character's animation so they wouldn't be in lockstep.
Using shapekeys like this worked for my simple animation, not sure if it would work for your situation. Sample attached.

Thanks for your reply! I actually found a video tutorial which shows an AN node tree that does exactly what I need, star a particle's animation when it's emitted: https://youtu.be/rmkiRjv7j5c

Excellent, thanks for sharing that!  It looks like a useful tutorial I'll learn from. So much power in AN!


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Physics properties: Will the render be accurate without baking?
I have a scene with lots of objects with physics on them. Dynamic paint, rigid bodies, wind, and turbulence. Now, getting all of this baked and packed in a .zip to send to a render farm is quite the hassle.
So my question is: is the baking process necessary for an accurate render, or will the physics be
calculated accurately during the actual rendering?

Sorry I can't answer that question regarding render farms, I can only tell from my personal experience in the past that sometimes physics simulations produced weird or unwanted behaviour when calculated "on the fly" while rendering the animation. But that wasn't always and I can't say anything about latest Blender versions, because nowadays I usually bake before rendering. My only advice is, if nobody can give you a safe answer, I wouldn't want to waste precious render time or money for the render farm just to find out it went all wrong.

I see, thanks for your input! I was going to use sheep it, so time or money is not an issue. Well I'll just pack the baked cache as well to be sure.

I'd say, without knowing anything about the project there's no appropriate answer. It depends on what you think is the greater fuss, baking all before rendering and pack the cache, or getting it done without baking at the risk to have to render it again.


text:
Start particle animation on-birth with geo-nodes?
This is really old problem that I among many others had, which is about animated particle instances.
Essentially what I'd like is for each particle to start their animations when they are emitted, not globally at the same time based on the timeline. To my knowledge, this was only possible previously with Animation Nodes using shapekeys, but I was wondering if this is possible now with the new geometry nodes, using any kind of animations, not just shapekey animations?


text:
Atmospheric falloff for volumetric materials?
I have a scene with volumetric clouds, and would like to have atmospheric falloff on them using the mist pass, however, as you'll see in this simplified scene, that didn't work.
Here's the scene. As you can see, there are clouds at varying distances to the camera.

If I render out the mist pass, the clouds are not visible at all.

Which leads to "incorrect" results on the clouds when adding the mist pass to the render.

Any ideas on how to solve this?


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Change extrapolation type from Python running in the background
I have a script that that changes objects in my scene and then creates and renders an animation of the object. It does this on a large batch of objects and makes the same four animations for each object. I typically run this from the command prompt with Blender running in background mode.
The problem I have run into is that I need the extrapolation type for these animations to be linear but I think by default is constant. I need a way of changing the extrapolation type from python while Blender is running the background.
I have tried the changing the extrapolation using:
old_area_type = context.area.type
context.area.type = 'GRAPH_EDITOR'
bpy.ops.graph.extrapolation_type(type='LINEAR')
bpy.ops.graph.handle_type(type='VECTOR')
context.area.type = old_area_type

However, this gives me an attribute error for context.area.type saying that it is set to 'NoneType'.
I looked closer at the documentation and area.type refers to subdivided screens within the editor. However, since my script is running in the background there are no area types to change to/from, thereby causing a NoneType error.
But, if I remove the area.type lines it gives me an incorrect context error for the extrapolation changes.
How can I change the extrapolation type from the background if I can't change the area type?

You can't really directly set the context.area.type, or any context property for that matter - it is a read only reflection of the current state of your scene.
To use the graph editor's operators under bpy.ops.graph, you need to override the context for the operator to "make it think" it's running within the graph editor. Here's an example how to do this for another operator.
But instead I would suggest changing the interpolation and handle types using lower level code instead of using the graph editor's operators. Here's a chunk of code that will do this for all of the active object's animation curves:
import bpy
C = bpy.context
o = C.object

# Iterate over all the objects animation function curves
for fc in o.animation_data.action.fcurves:
    fc.extrapolation = 'LINEAR' # Set extrapolation type

    # Iterate over this fcurve's keyframes and set handles to vector
    for kp in fc.keyframe_points:
        kp.handle_left_type  = 'VECTOR'
        kp.handle_right_type = 'VECTOR'


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Add material and apply Diffuse color via Python
This may be another simple question but I can't seem to find a straight answer.
I am procedurally generating figures and as part of the last step I want to color the figure red.
If I manually add a new material to the figure I can change the color with bpy.context.object.active_material.diffuse_color = (1, 0, 0)
But I need to automate this step such that the program automatically add a new material and then changes the color. I've tried the following but it doesn't seem to work:
bpy.ops.material.new()
bpy.context.object.active_material.diffuse_color = (1, 0, 0)

It seems the problematic step is adding a new material. Any help would be greatly appreciated.

These are 2 questions asked and both have duplicates: 1: http://blender.stackexchange.com/questions/23433/how-to-assign-a-new-material-to-an-object-in-the-scene-from-python/23434#23434, 2: http://blender.stackexchange.com/questions/23436/control-cycles-material-nodes-and-material-properties-in-python/23446#23446

Actually, I figured it out shortly after posting the question.
Instead of using:
bpy.ops.material.new()

I needed to use:
bpy.data.materials.new(name="MaterialName")

So the final solution was:
activeObject = bpy.context.active_object #Set active object to variable
mat = bpy.data.materials.new(name="MaterialName") #set new material to variable
activeObject.data.materials.append(mat) #add the material to the object
bpy.context.object.active_material.diffuse_color = (1, 0, 0) #change color

Won't always work as obj.active_material will not necessarily be mat

Just use mat.diffuse_color (or bpy.data.materials['Materialname'].diffuse_color) instead.

You're a real hero!


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I'm using 'Preserve Volume' but my model is still going flat when posed?

Did I do something wrong with the model? No matter how I try to weight paint, the leg still flattens. Is my 'Preserve Volume' tick not working?

Is it a 2D or a 3D mesh? Preserve volume is intended for 3D volumes, and is a little help that cannot be a remedy for bad geometry. If you want counselling on how to improve your deformations I think you should upload your .blend file.

maybe it's a problem of IK rotation, could you share your file? https://blend-exchange.giantcowfilms.com/

@joshsanfelici Its a 3D model and its a lower poly remake of a character of mine. I can upload the file if you want:


text:
The 3d manipulator widget just isn't there. Enabling/Disabling it does nothing
Yeah, it just vanished. I pressed the "enable/disable" button, but it still doesn't show up.
Where could it possibly be? What even happened to it?

are you in 2.79 or 2.8?

I'm on 2.79b. Should I update it?

Have you enable the "Use a 3D Manipulator" button on the horizontal menu bar on the bottom of your 3D View? Or perhaps in the Preferences > Interface, enable the Manipulator option?

Yeah, nothing happens. I'll try again, though, and see if something is different after a restart.


text:
How do I fix a tear in model
I don't know how to explain it but I'm pretty sure a picture is more than a thousand words. Problem is I have this tear in my model. How can I fix this?

Not sure I understand, but if this is to merge the selected vertices, use Alt+M

Selecting those 2 split vertices hit AltM then merge either at first/last selected or center


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Blender screws up materials somehow
Okay, I have this problem...i am running blenders latest version on a MacBook Pro. I have been working on this project for the last few days and I went to start up blender today and all the material textures are screwing up and turning into this odd color-coded mess material over everything that I previously placed a realistic texture...
Any ideas i would love to here, thanks.

I found that it has something to do with the Denoiser... if i have it on it does this, when i switch it off and continue to render there is no glitch... but because I'm on a potato of a mac i really need the denoiser to save my life here... It's just a bug i think.

Yeah probably a bug. Seems pretty significant though, I would report it.

so the denoiser is affecting the viewport?

Leo, yeah ha ha.. Thanks, it is a bug and hopefully shall be fixed in the next update as ther denoiser is still in alpha stage... Thanks!

David, Yes the Denoiser is affecting the Material and renderd view port of Blender. Even once i have final renderd it will still appear. Hopefully they fix this.


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Blender VFX Shadow Catcher Screw up
I have been working on a small short film that has a small section of VFX work, However; when I was rendering a test result to see if everything was working the way it needed to, the render did not seem to go as planned. As seen below, the Robot has no casting shadow, instead, it has a plane with a half opacity it seems, anyone that have done VFX before in blender would know that blender creates a plane for you and makes it a shadow catcher. idk whats going on. if anyone could help that would be great :)
Thanks, -Adam

Sorry but this still doesn't answer my question... The layout on that post is different and not using Motion Tracking.

Wow thank you very much Cegaton, i'm still kinda new to this motion tracking with blender...


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How to get glare on "Quick Smoke" (Fire & Smoke explosion)
I have this question that relates to Blenders Quick Smoke tool. Recently I have been rendering CGI explosions and smoke assets to be keyed in later on a short film, but I have this small problem that I think would make the explosion look a ton better, but I just cant quite figure out how to do it. Now as we may also know using composting, you can have a glare node on specific light sources to make the scene a lot more realistic, but Im trying to figure out how to do it with explosions. As seen below I rendered out this fairly simple explosion but I would really like it to have a glare to the flame parts of it.

Thanks if anyone has any ideas, also a quick side question as well, is there a way to hide the emitter (The sphere in the middle) [Cycles]. Thanks

You can check this video, as well as increasing the emission strength of the fire material
https://youtu.be/ctd_09qHacA?t=35m3s

Hello! Thanks for the response, however; im not looking for a way to increase the Fire Emission, instead, adding some sort of glare filter to the image, as you would if you where compositing an image. Now that im thinking of it i may have to do it out side of blender and somehow how add some filter in post.
But thanks!

In the video explains how to add the glare filter in the Blender Compositor, the comment about increasing the Fire Emission was because maybe you want to increase the intensity of the glare filter, and to do that, you need to increase Fire Emission

Okay thanks! i will make sure to check it out once i'm on my computer, thanks for the help!

This site is not based on solutions accessible via external links, they can quickly expire, please describe your answer directly in your post.


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How to get PURE fire in Quick Smoke preoperties
another question here for today.
Im playing around with fire and smoke simulations, and I was experimenting with "Fire & Smoke", and i get, as expected, fire with smoke. But when i go with "Fire", it also gives me Fire with smoke. I just want Pure fire without any smoke, and i think it may have something to do with Nodes. Thanks, if anyone has any ideas.
Thanks.


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How do the number of cores in the CPU relate to the rendering tiles?
Im not sure if this is a noob question but i was intrigued about something that i haven't thought about before. When rendering an image, its obvious to see the rendering tiles rendering away the image (the orange squares working on the tiles). But i never thought about this, do they relate to the CPU at all? like to get more rendering tiles, do i need more cores in my processor? The more cores the more orange squares? anyways thanks if anyone would know an answer.
Thanks.


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Multiple collections for Rigid Body
As written in rigid body physics docs
Allows rigid body collisions allocate on different groups (maximum 20).
How do I use Multiple collections for Rigid Body simulations ?
I see only one collection holder in the rigid body world.
It means support for nested collections under the given collection ?
clarification is welcome.
Thank you.

just wanted to mention -
the simulation will also affect the objects in the nested collections inside
scene.rigidbody_world.collection

I can't answer on the python part. But from what I understand about collections in Rigid Body:
If you keep the RigidBodyWorld collection that is selected by default in the Scene panel > Rigid Body World, and which is a kind of virtual collection, all the simulations will be played, regardless of the collection in which the objects are part of. If you choose another collection than RigidBodyWorld, the simulations will be played for the objects that are part of the selected collection only. Note that if you select the default collection back, it may bug (?), you just need to deactivate and reactivate the collection that the objects are part of in the Outliner:

If you select an object and go into the Physics panel > Rigid Body > Collisions > Collections there is another system of collections that maybe they should have called "layers" as it looks like a different system. Here you can select what layer the object is part of. The object won't interact with the ones that are part of another layer. If you press Shift you can select several layers so that the object is part of several layers:

Well, I wish it could work differently and support multi collections using python.
thanks for the clarification.

oop sorry if it doesn't answer, I don't know anythig about python, maybe wait for another answer

It is answer what the docs means which is great,
thank you for your answer.


text:
low level alternative to bpy.ops.rigidbody.world_add()
What is the non context depended way for adding physics to blender scene ?
at the moment i`m forced to select a scene and then use the ops function:
bpy.context.window.scene = bpy.data.scenes['Some_Scene']

bpy.ops.rigidbody.world_add()

thank you.

https://blender.stackexchange.com/a/136688/53513

Nope - that not an alternative but thank you.

No, there isn't.  world_add ends up calling a C routine BKE_rigidbody_create_world that is not otherwise exposed through the bpy API.
You would have to select a scene even if the C routine had a Python interface, because the rigid body world is attached to a specific scene, and the caller of the C routine would have to know which one.
If you wanted to add a rigid body world to a specific scene and didn't want to change the context, you could use a context override:
override = {
    'scene' : bpy.data.scenes['Scene']
}

bpy.ops.rigidbody.world_add(override)

replacing 'Scene' with the name of the scene you wanted to add the world to.
3.2 Update
Context overrides are deprecated in Blender 3.2 and are scheduled to be removed in Blender 3.3  The replacement is temp_override. The manual has examples of how to use the new function.

Thanks mate,
I can reference the scene as object - why it should be active ?
and if i must,it brings me to write this question
https://blender.stackexchange.com/questions/265266/how-to-set-active-scene-with-bpy-context-window-scene-thru-headless-mode
Do you think blender guys will change this design limitations in the future ?

It doesn't always have to be active. You might be able to use a context override in the call. Not every bpy op allows context overrides, but this one might.

Same None :-( or maybe i do somthing wrong.
using  bpy.context.copy()
gives
{...'window': None, 'window_manager': bpy.data.window_managers['WinMan'], ... }

@barakooda I updated the answer to show how to do it with an override.

Thanks mate!
This override trick really helps !
will use it more.


text:
Get Bone directions
As far as i was able to notice,
there is option to get the direction of the bone using bone.vector .
what if i want to know the side or up vector of the bone ?
There is at-least option to get the points of the box that represent the bone
transform , so i will able to calculate it my self ?
Happy new year !
thank you all for the help!

found my answer here :
from :
https://docs.blender.org/api/2.79/bpy.types.PoseBone.html?highlight=bone#bpy.types.PoseBone.bone
x_axis
Vector pointing down the x-axis of the bone. (readonly)

y_axis
Vector pointing down the y-axis of the bone. (readonly)

z_axis
Vector pointing down the z-axis of the bone. (readonly)

(old)
work around :
I will just stick box \ line on the center of the bone,
then will use the box points for the directions calculation .


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Saving render result directly to python object without saving on disk
I want to copy render result from memory to python object like list or later on numpy.
(without saving on disk)
After rendering
bpy.ops.render.render()

A new blender image object named "Render Result" appear in images
rendered_image = bpy.data.images.get('Render Result')

When try to access its data
rendered_image.update()

it says :
 Image 'Render Result' does not have any image data

Please let me know what is the correct way of doing so.
thank you.

I feel like this has been asked before, but it’s something I also want to know.

https://projects.blender.org/blender/blender/issues/53768


text:
fisheye formula of 3d world position to image space
Can someone from the dev team or other can share the fish-eye formula between
single 3d position in world space or camera space
into final image coordinates. (image space).
as used in cycles.
thanks !

There is no one from the Blender Foundation on this Q&A site. Suggest you ask on https://developer.blender.org/

I found the answer to your question in the functions direction_to_fisheye and fisheye_to_direction in the Blender source code: https://github.com/blender/blender/blob/main/intern/cycles/kernel/camera/projection.h. Even though the code talks about directions, I was able to use a version of these formulas to map 3D points from camera space to final image coordinates.


text:
Edit bones transformations with no context use
How to edit bones transformations while staying in blender "data" approach.
(no use of context)
getting this error :
AttributeError: bpy_struct: attribute "matrix_local" from "Bone" is read-only
A_obj = data.objects['A']
B_obj = data.objects['B']

bonesA = A_obj.data.bones
bonesB = B_obj.data.bones

for boneA, boneB in zip(bonesA,bonesB):
    if (boneA.name == boneB.name):
        boneB.matrix_local = boneA.matrix_local

The matrix_local of an armature bone is defined by the head, tail and roll of an edit bone.

@batFINGER sorry to hijack a thread, but matrix_local doesn't seem to update unless I toggle edit mode. Should we call an update method before trying to read it?

The head tail and roll of an edit bone define the matrix local of the bone. eg b.head == b.matrix_local.translation   and b.tail ==  b.matrix_local @ Vector((0, b.length, 0))  Any changes are not written back to data while in edit mode. (Whereas mesh has an update_from_editmode method, to do this) not aware of an update method other than toggle edit mode, for bones.

Copy a new one.
For the case where the desired result in target identical to source could simply assign it the same bones as the other with a copy of A's armature data, this will not only copy all edit bone transforms, but also all relations, parent, connected etc.
B_obj.data = A_obj.data.copy()

or even use the same armature
B_obj.data = A_obj.data

Converting Space.
Can see issues with simply copying local matrices from to when bone names match but not much else does.
To allow for changes in space between the rigs, like for example rig b having a different origin to rig a. see Python, How to get pose bone to rotate with another pose bone from a different armature? Finding Rotational difference re using convert_space to create matrices to copy from one rig to another.  eg in this case to take the local matrix of bone A and convert it to a local space matrix of bone B

As far as I understand now, modify armatures possible only with context
related approach.
this is my current solution.
A_obj = data.objects['A']
B_obj = data.objects['B']

bonesA = A_obj.data.bones
bonesB = B_obj.data.bones

B_obj.select_set(True)
bpy.context.view_layer.objects.active = B_obj
bpy.ops.object.mode_set(mode='EDIT')

bones_b = B_obj.data.edit_bones
for bone in bones_b:

    try:
        print (bonesA[bone.name].name)
        print(bone)
        target_bone = bonesA[bone.name]

        bone.matrix = target_bone.matrix_local
        bone.matrix = target_bone.matrix_local

    except:
        print ("removed " ,bone.name)
        bones_b.remove(bone)


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using random face corner attribute value for radomized color faces
Trying to use face corner attribute to randomize mesh face colors (grayscale at the moment).
Seem not to work properly so far.
Its weird that similar concept have done using python and bmesh, worked well.
I can try and use the UV and texture but its the last thing i want do.

don't quote me on this but I think  attribute transfers only works in Cycles in this setup

O my,
You seem to be right !
Lets hope it will change soon.
thank you.

I also think it will be fixed in V3.0 (due in december)


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Should my models be actual size?
I am making a battleship in blender and in real life, it is 887 feet. If I scale it up to the actual size, will things be more accurate or will it just slow things down?

Related What are the implications of a very large scene (scale-wise, relative to the default cube)?  Setting unit scale to 24 (for example) will make 1 blender unit approximately 8o feet.

It won't slow things down.
However, Blender's default settings may not be good for such a large piece.
Especially the viewport and camera clippings settings (these settings define the minimal and maximum distances rendered). The End clipping is quite small by default so if you happen to have your objects kind of cut in far distance, this is why.
You will find the viewport clipping settings in the View panel of the options bar (N) of the viewport, and the camera clipping settings are in the Camera tab (select the camera first), in the Lens panel :


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Background image not appearing in motion tracking render
I have another project that is exactly like this one but that one works, even though they have the exact same compositing setup. Any reason why this one doesn't show the background?
Blend file: https://drive.google.com/file/d/1Zsjwe7C50eo_h7rROzzBAzxy1M5y_gZI/view?usp=sharing

You need a layer with Alpha information if you use alpha over.
As you can see in the preview in the node editor your background is  gray instead of transparent.
To fix this just go to the properties window -> Render -> Film and tick transparent.


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Object Swinging
This is a very beginner question, but I don't know how to word it.
Let's say that I have a cube a distance away from my pivot and I set a key frame. Then, I move a couple frames and then rotate the cube around the pivot and set another key frame.
Obviously, the cube will move in the shortest path-a straight line-to the next key frame. How would I make it so that cube moves in the swinging/circular motion that I saw when I manually rotated it around the pivot?
Thanks in advanced.

Maybe I was showing too much of a broad of an example. I'm trying to make a rubik's cube to rotate one side, but each individual cube moves in the shortest possible path instead of the natural curve.

I get how that can change the speed, but how do you make it control the trajectory?

You can add an Empty object at the location of your cursor, parent the cube to it, then annimate the rotation of the Empty :
Shift+A / Empty / Plain axes (or what looks better to you, it's just visual).
Select the Cube, keep shift pressed, then select the Empty, and hit Ctrl+P. In the menu select Object.
Now if you rotate the Empty, the cube will follow.

Ok, but I'm making a rubik's cube so I would have to change the parents everytime I want to rotate a different side.


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Line appears in final render
In the LookDev mode, everything looks perfectly fine.

However, when I render the image or go into rendered view, there is a strange line between to vertices.

There is no crease and it is a flat face.

It seems these lines are a shadow from one light source. In look dev, there is a environment texture that enlightens the scene. But this light source is not used when rendering. Try to use several light sources or add an environment texture.

I suspect your faces are not actually planar - try viewing your face "side-on" as a visual check that all vertices are actually in the same plane. If not, adjust them so they are (one way to do this is to select the face in Edit mode, set your Transform Orientation to 'Normal' and press S, Z, 0, Enter to scale all vertices back to a plane (although this will distort your mesh).

This worked perfectly, maybe answer it instead of comment it so i can check solved


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How to constrain an object to one of it's local axes?
How can I make it so that when I move it around, it will only move on it's local Y axis?

Use G to grab then Y twice (Y and Y) to have local Y axis displacement.


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Switch all render layers back to normal
I originally had a motion tracking scene but now I want to get rid of it. I tried reverting everything back to normal like deleting the foreground and background and  every time I try to fix something it starts a whole new problem. Just fixing one thing would be a huge help. As of right now it won't render.
https://drive.google.com/open?id=1K-V7MpXHIMxf9NMI6AINt6JmXopBGbmZ

Hello, Caleb Lee. Use this link to upload your file: https://blend-exchange.giantcowfilms.com/

Hey, is the blend file from version 2.8?  I only have 2.79, and it won't accept 2.8 files

@RBlong2us yes it is blender 2.8

@LeoNas my file is too big for that converter...

Ok, is it possible for you to get me a 2.79 version?

nvm, just copied everything onto a new blender file

I just copied my entire scene onto a new blender file and everything was fixed.


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Different objects selected on different tabs
I am currently rigging a character and every time a make a vertex group for a bone, I want to test to see how it does. However, switching from edit mode from one object, to pose mode on another object takes time, and with a complex rig, this could stack up to lots of wasted time.
I want to have one tab on pose mode of the armature, and one tab on edit mode of the character. However, when I change the selected object, it changes it for all of the tabs. Is there a way to do this?

Maybe it won't make the process as fast as you'd like, but if you disable the Lock Object Modes option it will speed up a bit when you'll switch from the armature to the object and back to the armature.

This is quite helpful, but does this mean that there is no way to do what I wanted without using python of some sort?


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Low quality render help
This is my first post.
I am new to Blender and am following a tutorial to simulate an ink drop using smoke particles.
I have set up the simulation and have rendered some stills with cycles but no matter what i do i can't seem to get a crisp image.
I have cranked up the number of samples and have the image resolution at 1920x1080 (same as my computer monitor). It looks great when i zoom out to 1/3 the size of the image but when it is displayed fullscreen, it has this very low quality look to it. Not sure what i am doing wrong here. Please have a look at the images. I was hoping to upload my project file but couldn't figure out how to.
Below are images of the render and the render settings.

Many thanks in advance.

Try decreasing your Volume Sampling step size - this will increase render time but should make the volume render more defined. Also, consider swapping Sampling to Branched Path Tracing and increase the Volume rays in those settings and then increase Anti-aliasing samples until you get a sharp render (your current setup is using square samples of 48 which is 48x48 = 2304 samples so try Volume of 6 with Anti Aliasing of 400 (6x400 = 2400)).

To get a crisper image without increasing the resolution, try lowering the Pixel filter width under the Film section. A value like 1.1 usually does the trick for me. Also try playing around with the different filter types to get the look you're after.

Quick and dirty:
when the render looks fine when zoomed out just double the resolution and it should look good when displayed in screensize.

*Thanks can do for a temp solution but would like to figure out why it is not clear at the correct resolution. Any ideas?

Of course you can always raise the sampled. 2403 is not that much for such an effect. Try with 10000

Hmm. Ok will do. Will take forever on my hardware so will let you know in a couple of days haha


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My object appears jagged with shape keys and subsurf
So, I made a human face model and tried to animate some basic animations with it using shape keys. I was using subdivision surface to make it appear smooth as well.
(Also, if this could be the problem, I had just assigned everything to an armature)
In the middle of a blink animation, I noticed something strange about the eyelids as they were in mid blink, I paused the playback to see if I was right
And this is what I saw.

I turned off subsurf and I saw what it used to look like

Can I get an answer? I want this done soon, (tomorrow is best).
After doing a little exploration, it seems that the shape keys are only affecting one vertice at a time, and not vertices created by subdivision surface

If you need a fast answer, please upload your file.

Ok, so I figured out what the problem is;
So you know the list with all the modifiers on it?
Well, the subdivision has to be on the BOTTOM of the list, I moved it up to be able to access it quickly, but that made it so that it subdivided before the hook modifiers, making it appear jagged!


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Ambient Occlusion Help
I am trying to bake and ambient occlusion texture to my object but a few of the faces are turning up black. I know the are facing the right direction as I have recalculated the normals and flipped them manually in the shading/UV tab multiple times. IN the picture is hows a handle that I have built quickly  that has the problem. It is not a complex object at all just a spawned cylinder scaled down and extruded a could times and moved to look like a handle. I don't know why just a few of the faces are black doesn't make any sense to me. A lot of the cylinders I have used have the problem. Also the actual .png that has the textures laid out on it does not show the black just the red like it is supposed to be.

Just adding to my post the faces that turn up black do not have a texture at all in the uv image editor so idk why when i bake the model as a whole it misses these faces

If you add a file with blendexchange I will take a look at it when I get home. https://blend-exchange.giantcowfilms.com

 @SilverRain Thank You!!!


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Is it OK to have huge object library for using with BlendDataLibraries?
I'm developing command-line scripts that would need to get and append some objects from library, and the library is going to have over 9000 objects.
Will it overwhelm blender to have such huge library?
Question is whether blender loads and parses whole library file when it's opened, or it only parses it on demand when a particular object requested.

You might want to add a little more information here. Things like how big in terms of vertex count, materials etc. are your objects, what hardware are you using...

Does behaviour of blender depends on such parameters?

why yes, of course it does. More vertices means more calculations which obviously require more computing power.

so, you don't know if it loads all objects in file or only those that requested?

All I know is that the appending Blender instance doesn't work like a database engine and it doesn't "stream" the .blend file. There is also no separate "search index" to speed up the process, so I guess it loads all the objects.


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Maximizing Render Field of View in Interior Scene
I'm new to Blender and love most things about it, but the camera is hard to work with, especially in tightly enclosed interior settings.
When I've positioned the camera where I want it and bring up the camera view (Ctrl + Alt + 0), it only captures a small portion (maybe 50 percent) of what's in the viewport. When I try resizing the window, it doesn't go all the way to the edges, so the only way to get everything in the shot is to zoom out... but that's often not an option with an interior scene, because I end up going through a wall. Changing the focal length distorts the image.
Are there any other options to solve this problem? In most other 3d apps I've used, you can simply resize the render window to fit what you're seeing, and even go beyond the field of view. Is there anything like this in Blender? Are there some camera constraints I can turn off for this?

You can change the sensor size in the camera settings. Or you can change the focal length. But what about distortion for a wide lens - it's physics, you cannot cheat it. If you want, you can use orthographic, or panoramic camera (the latter seems to work in cycles only). If you want an impossible camera shot, you also can make some of your walls to be transparent for camera rays from outside, and make the shot through the wall with the lens focal length you want.

Those are useful workarounds, but not really what I was looking for. It's not an "impossible shot," as Blender clearly is capable of capturing that part of the image (if I hit Shift + Z, there it is). So the programmers have decided to artificially limit what I can do with the camera, I assume because they want it to match the limitations of a real world camera for some pedantic reason. So I was hoping there's some way to disable those restrictions, or perhaps someone familiar with Blender's coding can point me to where I need to go to hack the source code.

I think you really didn't try to play with Sensor size in the camera settings. Just go to camera view (numpad 0), and increase the sensor size until the view will satisfy you. Just think about the fact, that the viewport of the 3d view also mimics a lens (default is 35mm), and a sensor. So if you have the same lens in the camera, you can have the same view from the camera as from the 3d view. The only thing to change is the sensor size.

I see what you mean now. It's a slightly different method than what I'm used to, but it seems to be effectively the same thing!

new software - new buttons, but for centuries the idea is the same :-)


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Geo nodes: Translate a single instance
I'm using "Distribute points on Faces" and "Instance on Points" to distribute objects on a plane, and I would like to move/rotate only one of those instances. I want to avoid realizing those instances if possible. How could this be done?

just compare the index of the instance with the index node + compare node, use that for the selection input of set position node. Use position offset input to move your instance.

Awesome, that worked. Thanks a lot! (small addition for clarity: make sure the compare node is set to "integer" and "equal")

glad if it's helpful


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Distort procedural texture along concentric circles
I'm trying to distort a procedural texture along concentric circles, so far without success. I'm not even sure how to illustrate the type of distortion I want, so search google I found this image that shows perfectly what I'd like to achieve with a Voronoi type texture:

I'd also like this pattern to work in a 3 axis coordinate system so I can use it for volume densities, so it's really distortion along concentric spheres in 3D space. Is this possible with blender nodes?

You can use this nodes to achieve a similar effect:

This is good, but unfortunately it doesn't work in a 3 axis coordinate system due to the Radial gradient texture.

no problem at all

Can this be made to work as a volume material so it's the same pattern in the 3rd axis as well? Currently it looks like this: https://i.sstatic.net/uDUQ7.jpg

I didn't work that out yet, but doesn't Length or a Gradient Texture set to Spherical provide usable 3D information?

I've been going at it, too, but no luck yet. Curious to see if you can figure it out.

@GordonBrinkmann Any luck with this?

@Geri No, unfortunately not. My problem is that I don't actually understand what this Radial Texture in combination with Ping Pong and the Length does, and so I have no idea how to use the third dimension of the Length.

I see, thanks for trying anyway!


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Custom image/HDRI background for solid/wireframe shading modes
I have a scene where using the X-Ray feature of the Solid / Wireframe shading modes is essential to my modelling process, however, I need to see the background HDRI as well.
Material Preview and Rendered shading modes do not allow for the use of the X-Ray modes, and even if I go into Edit mode, I do not get the same see-through effect that Solid / Wireframe X-Ray gives. And I didn't find a way to show the world background in Solid / Wireframe shading modes.
Any solution to this?

Maybe try this, in Material Preview:
Of course enable the Scene World option in the Viewport Shading in order to see it when you are in Material Preview:

To see a transparent wire in Object mode, choose Display As > Wire:

To see a transparent wire in Edit mode, enable Viewport Overlays > Hidden Wire:

Awesome, that worked. Thanks!


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How can I "bend" object coordinates?

As you can see, the object coordinates don't bend along with the object itself. I know this is intentional, but is there a way to perhaps make them follow the contours of the object, or to manually bend them to approximate the shape, using vector curves maybe? I was unsuccessful with my attempts.

This is how I'd like the coordinates to bend.

I'm not even sure if that is possible XD. But can I ask why you need that? Maybe there is another way for you to archieve what you want..

Well it's complicated xD Essentially, I'd like to be able to use a volumetric material that is a thin, flat layer of cloud, stretched to a dome surface. The cloud has lots of detail made with procedural textures, and I'd like to sort of map that onto a dome. If that makes sense to you.

If you can align the object with the coordinates somehow, and then change it procedurally to the final shape, you can use the Generated coordinate space:

It shouldn't be too hard considering it applies also to shape keys.

Oh that's nice! Yes, switching to Generated shouldn't be a problem. Shapekeys will work perfectly for me, thanks! Unfortunately though, this won't work with volumetric materials that I need this for. It works well for surface materials, but not for volumetrics, as they do not bend with the mesh coordinates. Do you perhaps know a solution to that? I fear that may be a limitation of volumetrics in blender.

@Geri all 3 coordinates bend, so I don't see why it wouldn't work for volumetrics. Unfortunately I can't help a lot with that as I lost a small fortune rendering some projects with volumetrics and stay away from them ever since... How about creating an object guide, to which you apply the technique above, and then use that object's coordinate space in another object?

@MarkusvonBroady: you are making me curious!!! you lost a small fortune....how did you do that? You rented 10 renderfarms for a year?

@Chris renting 10 renderfarms for a year is only a small fortune for you? Can you lend me a few grands without a well precised payback date? ;)

@MarkusvonBroady : I never used Renderfarms so my experience is very very low….

@MarkusvonBroady That doesn't work unfortunately, the volume stays there and doesn't move with the mesh. Is there maybe a way to achieve what you showed through nodes? I feel like simply manipulating the mesh just won't do the trick with volumetrics.

@Geri I took a look and volumetric object ignores procedural transformations, that's probably what causes your issues. One idea to investigate is to reverse the shape keys like this: https://i.imgur.com/MI6Xbe7.png then bake the texture from 3 or 6 sides (but with 0..1 data instead of banding which I just use for visibility). 3 sides variant could be used to use the coordinates to read the texel on 3 textures, each showing the offset for different coordinate. The 6 sides variant is where you get 2 values and interpolate between them depending how close you're to one side versus the other...

Just an idea, no guarantee it would actually work.

@MarkusvonBroady Thanks for the tip. I'm not entirely sure how to do what you described. How would a baked 2D texture give coordinates to a volumetric material?

@Geri that's the problem, it wouldn't give it 1 to 1, you would cast the point inside a cube to a point of the nearest surface of the cube, to read how you should offset X,Y,Z coordinates (the offsets stored in RGB values of the texture). Or you could cast the point inside to all 6 sides and interpolate between them, something like this: https://i.imgur.com/SxUexZ7.png (you could combine 6 textures into one)


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EEVEE SSGI add-on question
After trying out the eevee ssgi add-on, I started wondering if using the add-on is really necessary? Because you can just append the node groups to another project without needing to even install the add-on. The add-on really only is just a few sliders in the N menu, which can also be accessed in the node groups.
I'm mostly curious about this for the purposes of sending out projects to render farms which do not support add-ons.
aDd-oN

Honestly talking , i downloaded the SSGI yesterday to use it with a project and immediatly removed it after 1 glance....didnt like it , but if u get what you like with it , then u should really keep it

Yes true. That addon is not that necessary. Mostly all of addons doesn't make sense if we think that it can be done manually. But, add-ons are created with the soul purpose of making things easier than it is. If your render farm do not support the addons than it's up to you weather you want to use it or not.

Honestly, I have downloaded SSGI add-on yesterday to use it for a project I work on and immediately removed it after some time playing around. I personally didn't like it but if you get what you want with it, keep it.Addons like this are not that Necessary because Addons do not implementing some new functionality, they are just taking 10 steps inside blender itself and shrinking them down to probably 2 and 3 clicks. I'm sure this would be also be possible to do using the built-in tools manually.
Talking about Render Farms which are paid per hour, don't getting the desired result compared to your viewport, then it is wasted money for sure but nothing that you can fix by yourself (as you mentioned) so I'd suggest do not use it in combination with render farms that actually don't support the add-on or ask the support team whether you can use it on their farm beforehand.

@brockmann,  will keep in mind

Just a suggestion, roll it back if you don't like it.

Thsts actually better , tq @brockmann

Judging by your wording, I feel like you misunderstood my question. I'm not asking if it's necessary because it's a good add-on or not, but because you can use its functionalities without needing to install and use the add-on -- you can just append the node groups from another project, and get the same result -- or, that's what I'm actually curious about if that's true (though judging by my own testing, that does seem to be the case). Also I'm using the Sheepit renderfarm which is free.

@Geri if you are getting the same results then that really good and sheep it render farm is free , that's also good , by your question , yeah its not necessary and because you can append the node group from another project that works fine then you git th answer your self , that its not necessary …


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Edges Look Uneven
I've been searching for and answer but can't seem to find one. i'm not 100% on how to explain but i have attached a image.
The edges on my model don't look straight they seem to zig zag there way up. is there a way to make it completely straight? i am only new to blender.
Thanks in advanced.


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Ways to create woven rattan garden furniture?
I'm working on a scene and need to model a garden chair with woven material similar to this:
https://www.bau-outdoors.co.uk/shop/outdoor-furniture/garden-dining-chairs/montreux-woven-rattan-garden-chairs/
I have modelled all the frame of the chair but am struggling to come up with any ideas of how to create the fabric. The frame is alot more curved than the image so would need more work to get it wrapped around. Would it be possible to use a normal map and a texture or is there a way to use arrays or a cloth sim to get it to wrap around properly? Any help would be greatly appreciated as I am replicating an image so would really like to keep it accurate. The chair is not the focal point so does not have to be perfect.
Thanks

https://blender.stackexchange.com/questions/19317/creating-a-thatched-rattan-material

tutorial


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Different view from viewport than the render
I am a beginner in a blender and this is my first model. I have a problem because the final render is not the same as rendering the viewport. I do not know if this is a problem with the rendering settings or the model. I add screenshots and file.
And sorry for my english, im from Poland and still practicing.
View from viewport:

Render:

File:
https://drive.google.com/open?id=1b76DHKwo7jI0lJFjp9LYZqWLeJivarTh

For the bottle you have different levels of subdivision (1 for preview, and 2 for render). That gives the inconsistency.

I was changing subdivision settings in many different ways and applied on model, and nothing got better.

Ok, sorry after restart render view i see flatter render. But how to get the result from the earlier viewport :/

We all have your old blend file as a backup. :-)  So it's easy to roll back. As for differences, maybe your solidify modifier. It's disabled for preview, but enabled for render. (those little eye and camera icons).


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I can't add drivers
So, I know how to add drivers, but for some reason it is not working at all.
I go to my object and hover over rotation on the Z axis, then I press ctrl+d and choose Single from target and the problem begins here I think. I use the eyedropper to choose my target, but I doesn't work. When I press on it the eyedropper just disappear like I added the target. But when I go to my graph editor (I choosen to show drivers no graphs) it is not there...
Am I doing something wrong?
Thank you in advance,
Leonardo.

The eyedropper needs to hover a value, not an object; so in order to use it you have to open two properties panel, in one of them choose the target (in my example the sphere), pin it with the little pin icon, choose the source in the other panel. Anyway generally you will have to edit the added driver because often Blender doesn't guess exactly which value will drive which target value.


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add controls to already generated meta rig
I saw some answers to similar question here, but either it doesn't match my needs or I did not understand them.
Long story short: I didn't change rigify type on the fingers to super_finger but I already did the weight repaint job and generated the rig. Do I have to redo the whole thing? Is this losted hours of work?
full story:
My problem is I have an already generated metarig. I did aaaaall the weight paint corrections (there was a lot because I added few custom bones to the original armature, like a bag, some swords etc) But when I started animating, I noticed there was no controls for the fingers (you know, the lines you select and scale to retract fingers) I found out on stackexchange that I should change the rigify type on those fingers to super_finger instead of tentacles. Do I have to regenerated the whole thing and redo the whole weight repaint job again?
Thank you

The weights are properties of the vertex groups, so they belong to the mesh object, no matter which rig you use. They get overwritten only if you perform an automatic weighting or a "with empty group" option.
So you can create the new rig and parent it to the mesh using the simple "Armature deform" option.
The names of the new rig bones should be the same as the old, so everithing should work fine (except for the new fingers bones, of course).
Later you can also perform an automtic weghting limited to the new fingers bones, to have a good starting point to be refined with weight painting or direct weight assign.

Thank you, I'm trying that and let you know

That worked seamless! You just saved me a big time. Thank you so much


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Bake object with many parts
I need to bake this model for a game, but there are lots of small cylinders. If I join all the objects, the bake comes out with lots of black spots. Do I have to manually bake each object or is there an easier way?

I suggest you to "explode" the geometry and then bake,
explode means; you take everything apart so there is a margin between they, you have to do this for every pass except the ambient occlusion pass
-separate the pieces when there is a weird angle(not sure of this last pàrt)
Supplementary:
this video shows the process done in maya and substance painter, but its the same for blender
https://www.youtube.com/watch?v=3fY3LEnoRxU&t=7s


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Animate Collision On and Off
I have an object that a cloth is colliding with, and I want the collision to be disabled in the middle of the animation. However, I cannot just turn off object Collisions on the cloth, because there is another collision object that I want the cloth to continue interacting with. I cannot find an 'on/off' switch in the Collision properties. In another forum, scaling the collision object worked, but doesn't in my case because it pushes/pulls the cloth. Is there a way to animate collisions to turn off or another solution around this?
(I am using Blender 2.81a)

To essentially stop colliding with one particular object, or to have one cloth stop moving, and another one continue to react?

I want the cloth to react as normal to all objects. The only thing changing is that 1 object 'vanishes'

You could render animation to the point where the object disappears, delete the object, and render another animation starting from the point where the first animation left off. Combine the two scenes in an editor.

Technically, this question should be called "Animating the permeability of a cloth collision object".

YES you can Turn ON and OFF of it's visibility in simulation:
Try insert Keyframe on the eye icon by pressing 'i' key:

Then on the frame where you wanted to turn it off, enter '0' manually here:

And it's no longer colliding with anything as shown here:

The answer is: No
You can not directly animate the modifier so that it will be cloth-permeable, but you can easily find ways around it.
I fixed this problem by running a simple small animation myself, a cloth plane falling on a cube with collision settings, and a large plane (with collision settings to act as the floor).
I animated the cube with a LocScale keyframe at frame 1, 50, and 75.
At frame one I added a single keyframe to the cube without doing anything.
At frame 50, I did nothing to the cube, and set another keyframe.
At frame 75, I scaled the cube down to .0001 size, and moved it beneath the plane.
The final result is that the cube shrinks below the cloth, and gives the effect of the object disappearing.
I believe this is the best way to animate these kinds of simulations, so I hope this helps you.
Here is the .blend. (Note: you may need to re-bake the cloth):

Here is a video, too, if you don't want to have to download the .blend.


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Where can I find the number of vertices, edges, and faces in my scene in Blender 2.8?
In Blender 2.79b, you could see the number of vertices, edges, and faces in your scene on the bar at the top. Is there a way you can access this information in Blender 2.8?

Bottom right corner in the status bar.

+1.. i have a big @ss thunderbolt display... need to look around more before throwing my hands up in the air and searching on SE..

My stats were missing from my status bar somehow and I had to right-click the status bar to bring up the option to display the info I wanted to see

That's Blender 2.9x isn't it?

Correct, 2.9x. I thought I'd add it seeing how this thread came up when I searched for the issue and it's nice when old issues have updates.