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Missing AO panel & increased Cycles render time in 3.5 vs. 2.93
I had a simple setup made in Blender 2.93.9 (see file here) which combines 2 scenes in the compositor:

Main scene, which renders an object in Eevee
Shadows cast on a plane shadow catcher in Cycles

The composite result in Blender 2.93.9 looks the way I want:
But when I render the same file using Blender 3.5, I get this:
The Cycles shadows are much darker. I figured this might be caused by the AO, but I can't find the AO settings for Cycles in 3.5. In 2.93 there was a specific panel in the world settings, which looked like this:

Where is this panel & how do I adjust AO settings for Cycles in 3.5 ?
The second issue I have with this scene is the render time: around 2" on my hardware using 2.93 vs. 30" on 3.5, which is 15x render time ! I can improve this a little bit by disabling the Cycles denoiser without too much loss in quality (it's only for shadows). This reduces the render time to about 8 seconds, but that is still 4x render time.
What changes brought to 3.5 cause Cycles to take so much longer ?

In Render Properties under Light Paths you will find a Fast GI Approximation check box and dropdown menu:

The other option is to use the Ambient Occlusion node in the Shader Editor with the World Shader selected.

The Fast GI Approximation is something different; from what I understand, it mixes AO & real ray tracing for faster renders. If you run the .blend file I provided on 3.5, you will see that the option is activated, because the panel you point out was already available on 2.93 and I created the file on 2.93 with the "Fast GI" option on. The so-called "Ambient Occlusion" panel I'm looking for (see pic in the question) seems to have been completely removed on 3.5. There's a new option which allows me to either "Replace" or "Add", but neither of those are equivalent to what I used to get on 2.93.

Fair enough. I've not really investigated AO changes between versions.

The AO node seems to be a decent workaround, although I don't get exactly the same result. Thank you for taking the time to answer.

Actually I just searched with Google and found this answer from CGCookie.

So, after some extensive research (see this article), I found that the "Ambient Occlusion" panel from 2.93 that I was looking for might not be actual AO, but more like global illumination which adds on top of the Cycles ray tracer. Of course, this is not physically accurate, which might explain why it was removed on later Blender versions... But what if people like me were using this specifically, as some kind of effect ?
For now, the best workaround I found to get this to work on 3.5 is to increase the World Background strength from 0 to about 1.1, to simulate the loss of the so-called AO. I don't get exactly the same result as on 2.93, but at least the shadows are not that dark. As @John Eason pointed out, it can also be done using an AO node in the World Shader, the results are very similar:

However, neither of these 2 solutions are a perfect replacement for the old so-called AO panel, especially if you render the whole scene in Cycles:
Scene in 2.93 with 0 strength background, but so-called AO panel on. This is what I want.

Scene in 3.5 with 1.1 strength background, or AO node in World Shader. Current workaround, not the same, but it looks OK.

And there's still the issue of render time...


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Vector Math (Multiply) chosen axes x 1.0 vs Combine XYZ node?
I have a Geo Node housekeeping question today that I can't quite answer with what I've read/found.
Disregarding specific use cases, which method is more expensive to isolate a one or two axes along a node formula?
a.) using vector math to multiply the axis by 1.0 or
b.) using a combine xyz to socket into the chosen axis
Maybe I'm asking if the math is calculated on all the empty sockets/fields for each node, I'm not really certain. Are they both the same in cost? (I'd like to know if they are different even if the difference in calculation is insignificant.)
Thanks for your time and thoughts!

(Using Blender 3.6.8)
The following GeometryNodes modifier is creating a $10^6$ points cloud.

In a first test, points are projected along the X axis either by multiplying their Position by the vector (1,0,0), either by separating& combining their X coordinate. Switching several times, to get some statistical trend, shows that both approaches run at about the same speed.
Multiply node:

Separate XYZ and Combine XYZ nodes:

In a second test, identity transformation is applied either by multiplying Position by the vector (1,1,1), either by separating& combining the three coordinates. Switching several times, to get some statistical trend, shows that the speed of the Multiply approach is unaffected whereas the time increases significantly for the Separate & Combine approach.
Multiply node:

Separate XYZ and Combine XYZ nodes:

Resources:

Interesting! Thank you! I don’t think I fully understand, so I would guess that some of the increase is contributed by the use of the additional node separating the coordinates. Is there a way to isolate combine xyz vs vector math (mult) for a similar test? Or am I missing the point (no pun intended, but ha, ha) entirely?

source: Stack Exchange

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

sort: votes


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Manual: Mix node update in 3.4 NOT forward compatible?
I'm confused by the syntax in this sidebar tip in the 3.6 manual:

Is this a mistake that should read "backward compatible" or "old node"? Or is the update to mix nodes for 3.4 only usable in 3.4 and thus mix nodes must be replaced in projects made in 3.4 for all future iterations of Blender 3D?
Further: is it backward compatible if not forward compatible?
I assume (if this is an error) that it means "backward compatible" due to the use of "As of" v. 3.4 (suggesting the mix node is broken since 3.4 and no note of an update since), but I don't have any 3.4 files with mix nodes to test this from. Is there any insight on this?

Maybe you could get some clarification at this link: https://devtalk.blender.org/c/documentation/12

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


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Problem with Z buffering with leaves on a tree
The leaves are behaving as if depth-buffering is disabled, so those closer are being rendered over by those further away.
I've looked for a solution or someone with a similar problem, but haven't been able to find anything relevant. I get the feeling the solution is something stupidly simple, but it has eluded me so far. I would rather have uploaded a blend file, but I cannot for the life of me figure out how to do it on this website, so I've taken 3 screen shots of the problem, each one slightly rotated to hopefully help you see what's going on.
The problem doesn't happen when the leaves are instanced onto the branches, but the moment all the objects are combined into one mesh, sharing one material, this starts happening. I've tried using images both with an alpha component, and ones without, and it makes no difference.

The problem that you are faced is well known. As of now Eevee does not support per-fragment (pixel) sorting or per-triangle sorting. Only per-object sorting is available and is automatically done on all transparent surfaces based on object origin.
Then you convert instances, all per-instance origins removed, and alpha sorting works as the model is a single object from alpha sorting perspective.
So as a compromise, you can enable Alpha Clip Blend mode in material settings:

I could kiss you! Thank you very much.


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MIrroring a Hexagon (other than 90°
I'm a total newbie, and I'm tring around right now with some modeling.
My plan is to do a hollow Hexagon and to cut holes in the 6 sides.
Is there a way to mirror it?
I only find the "normal" mirror for the 3 axis with 90°.
For the HExagon i neet other angles.
Thanks for the help and sorry for my bad english.
Happy

Maybe use an Array modifier with an empty as object offset instead of a mirror?

See my answer here: https://blender.stackexchange.com/questions/292075/how-do-i-add-a-mesh-to-a-face-which-is-45-degrees-to-either-the-x-or-y-axis

Thank you for the tip with the Array (https://blender.stackexchange.com/questions/292075/how-do-i-add-a-mesh-to-a-face-which-is-45-degrees-to-either-the-x-or-y-axis)


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Where's the shadow light pass gone (cycles)?
I'm following a tutorial (very beginner here) which wants me to enable the "shadows" light pass in the view layer - the tutorial is in blender version 3.2, which the docs say has this, but I'm using 3.5, which doesn't.
Has this moved? Is there somewhere I should look for equivalent functionality, or has this just been removed?
The usage of it is here from 13:40, if it makes any difference.
Thanks in advance!

It's just been renamed to Shadow Catcher (basically the same thing) - it's still in the View Layer properties under Light > Other:

There's a good video on it's usage here - https://www.youtube.com/watch?v=PeVyu9DPmUk

Thanks - I'd missed that as Shadow Catcher was in version 3.2 as well, cheers!


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How to get same UV Editor view in other workspace?
I'd like to have a UV Editor open in the Shading workspace so I can rotate and scale the unwrapping while I alter the material (instead of having to go back and forth between the two workspaces), but when I naively try and do that, it doesn't show the layout of the model in the UV Editor view.
In other words, I'd like is to get the same info in the UV Editor that I put in the Shading workspace as already exists in the UV Editing workspace - how can I do that?
(Additionally, I'm able to rotate and scale the UV unwrapping in the UV Editor no matter what material it shows, but it'd be nice to have it automatically keep up with the material of the currently selected object - is there a way to do that instead of having to switch to it manually in the UV Editor?)

Found after I actually started getting to work, I keep forgetting you have to go into Edit Mode to activate the UV Editor.
Would appreciate if there is a way to make it so the UV Editor shows the layout in Object Mode though.


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Why is the hair in these models not rendering as I expect?
I downloaded these two models to play with, and importing them into blender, their hair is obviously recognised in some respect, but not how it should be... anyone know what I'm doing/is going wrong?

in the Particles panel, under Children, is the Render Amount the same as Display Amount?

The hair material has a transparency map and you are rendering the models in Eevee, which is in my opinion not great for objects with transparency. Most likely your hair material is set to the default Blend Mode > Alpha Blend. Switch it to Alpha Hashed for all hair materials (and the "Scalp Transparency" material), this should look better:

A much better result you get rendering in Cycles without the need to change any setting on the hair materials:

That's it, thanks very much - I always forget new scenes default to Eevee!

@JohnGraham If you don't want to use Eevee by default, open a brand new scene, switch the render engine to Cycles and go to File > Defaults > Save Startup File.


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Textures from Substance look sharp at UV seams
I exported my textures from Substance Painter and I wanted to make some renders but I get this weird shading at the UV seams. The edges aren't marked as sharp, I've smoothed the vectors, the Normal node is non-color. Where is the issue coming from?

Hello, maybe share your object or at least a part of it, don't forget to pack the image

First, rule in/out the cause.  Are seams still visible on disconnecting normal map, for example, or are they visible in all textures?  There are two main concerns when using SP + Blender in conjunction: 1) OGL vs DirectX coordinate systems; to use in Blender, you want an OGL bake (if you have a DX bake, you can invert G channel of normal map instead); 2) SP and Blender do not triangulate meshes in the same way, and this affects normals + UV interpolation; triangulate meshes before sending to SP.

I checked my maps and inverting the green channel does help, but the problem seems to be in the low poly model. Even in Substance Painter the textures bake from the HP model well, but when I look at the actual texture the UVs act like individual planes if that makes sense. Here's the model


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How to quickly cut out these shapes

I want to cut this out into shapes the model is hallow btw. I need this to make a lantern and I can't figure it out.

Hi Please use a title that reflects the content of the question. It should be descriptive but succinct, unique and identifying, summarizing the issue so that users can at a glance understand what your post is about. Use the [edit] link below your post and avoid anything not strictly essential to the post. Remember, your title is the first thing potential visitors will see, and makes your question findable for future users. See "What is the problem with posting an image or link and asking “How do I do this?""

Create your pattern, it needs to be tileable:

Array it:

Use a Simple Deform in Bend mode to make it bend 360°:

Give it thickness with a Solidify modifier, deform it with a Lattice cage:

Thank you so much! this helped out a ton!


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One of my objects won't show in my F12 or final render
I've tried to render my scene but there's an object that won't show up. I've checked the camera, I've checked the visibility, it isn't hidden and it's showing in the viewport. I feel like I've opened every setting and have achieved nothing.
I’m trying to render a book with a cover, flipping pages and stacks of pages. I have no idea how to fix the fact that the book cover doesn’t render. If I create a plane and select both the book cover and the plane and join them with Ctrl+J, the render contains a book cover but it doesn’t turn as it’s rigged to do so because it’s now linked to the plane and loses all the animated properties.
As soon as I unjoin them the book cover stops rendering and everything appears as you see it there, a book with binding, pages, but no cover. For the life of me I cannot figure out what’s going on.
Here is an image of what I want it to look like with the insufficient fix:
https://drive.google.com/open?id=1SjhNP9H_sebq0J0v8qn89SyKcTQb366g
Here is an image of what it comes out like:
https://drive.google.com/open?id=10uGX-7Sofb5DSG-eI_PHdyXur6zMTMQL
Here is an image of the settings in my project:
https://drive.google.com/open?id=1ARbn-s2rY2jcHrvfv_06y5C6My6HZHhG
Here is an optional link to my project:
https://drive.google.com/open?id=1Cfk05_-aZB1LpQat-6RGKB9IiDHZNffZ

https://blender.stackexchange.com/questions/215398/object-wont-show-in-render-none-of-the-suggested-solves-ive-found-have-helped

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

In the Properties panel > Object > Visibility, disable Shadow Catcher


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Material at Viewport Shading some lines seem to appear
I have a problem with my material at Viewport Shading, some lines seem to appear. How can i fix this?

Looks like probably Z-Fighting, see..https://blender.stackexchange.com/questions/5441/cause-of-black-artifacts-in-render https://blender.stackexchange.com/questions/21/how-do-i-avoid-rendering-glitches-from-overlapping-faces


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How would one change the way that a mesh deforms, such that a specific area does whilst everything else is left intact?
Practicing rigging and I had added an armature bone to a box with a slit in it to simulate rudimentary lip movement. However, it didn't just move the lips, it also deformed the box itself. I was wondering if there was a way I could change the deform modifier such that only the region where the slit exists deforms but everything else doesn't.
Drew a diagram of it:

please add blend file, we have no idea how you did setup this and how you did weight paint....thx

Add a few more bones that follow the box shape. The new bones will limit the influence of the existing bones and stop the deformation. The weights define how much influence each bone has. As an example, look at the Rigify face rig. The bones around the mouth deform the mouth while the cheek & jaw bones stop the deformation of the mouth and keep the rest of the face stable. The same applies to the eyes and forehead, and so on.


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Particle different in Render and Viewport
I have a particle system that looks different in the unbaked, as well as baked state in the viewport than in the render, in the viewport everything looks normal, in the render suddenly some particles are missing or hanging in space where there would be none in the viewport.[][1

yes, still the same

The problem is also inconsistent, I bake it with slightly different settings and it then suddenly shows the correct particles but not all in the render.

I have found a workaround, if I bake the particles and deactivate dead under Extras, then it does not show me particles in the render, but if I then activate dead again, the missing particles become visible.
As an addition, if I activate dead and then bake, I see too many particles in the render, logically, but if I then switch off dead, too many particles disappear again.
At least I have found a workaround.


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How do I separate by object, not by meshes or vertices?
I’m new to Blender and I wanted to know how I can quickly separate the objects below not by their vertices/meshes but rather by each of the models themselves. I use Sketchup and Enscape as my rendering engine for Archviz. The model I download seems to have different models joined together even though each object is distanced from one another. Blender’s textures can’t be imported to Skp. Whenever I try to import the Blender exports (obj file) to Skp and I try to edit the materials there, the objects are separated by the meshes as seen in Blender. Trying to separate each by selecting vertices is a hassle since there are a lot of them per object. Please see the photos below for reference. Thank you

In Edit mode press 'A' to select all the vertices then, press 'P' to separate from selection, by loose parts, or by material. See if any of these options fits your need

I'm not completely sure I understand what you're asking but I use two ways to separate multibody meshes into separate parts while in edit mode:
1: Select the vertices of interest and press P to separate them. A quick way to select linked vertices is to hover over one of them and press L.
2: Press P and choose "By loose parts". That will divide all separate meshes into their own objects.

But each object, ex: stove, have a lot of vertices and some objects are quite close to each other so selecting vertices of one object sometimes leads to misclicks on another object's vertices

@Carl Salen if you press L it will select a separate mesh within an object, and it won't select another mesh, even if its close or intersecting with the one selected


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Giving individual particles cloth physics, and alternatives?
I wanna make a slime type creature that leaves behind puddles of slime as it jumps around the scene. I had the idea of attaching a particle system that emits cloth-physics spheres that collapse when they hit the ground. I have the sphere with the cloth settings I like (left,) but the emitter doesn't produce its own instances of the sphere so the particles simply copy the state and position of the reference(right.) My goal is to have an emitter that produces individual spheres that each have their own states, so my slime can leave a trail. Does anyone know how I should go about this? Is an emitter the right way to go, or is there another way for me to spawn these puddle spheres throughout the animation?

This is a very difficult and impractical way to go about this . I suggest using dynamic paint with a displacement modifier instead.

Hm, I never looked into dynamic painting before, but after some initial research it looks way more optimized than what I have going on now. I found a solution using animation nodes to duplicate the reference mesh and replace the particles with the duplicates, but I will definetly look into dynamic paint/displacement and do some comparisons to try and get similar results. If I can get results looking similar to what I already have, it would definitely make my animation go a lot smoother!

If you got some solution don't hesitate to answer your own question so others can learn from you. Thanks :)


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Render Solid Background Color Artifacts
I'm trying to render my models as pixle perfect sprties for a game.  I'm rendering with a clear background using the transparent film setting, then adding a solid color (RGB 0,0,255) as the background with compositing nodes : Render Layers -> Alpha Over -> Composite.  The 3d models render correctly, my problem is the background is not a solid color, but has some shading or variation across the image, which messes up the background for my sprites.
In the picture, I've imported the render into paint.net and used the magic wand tool with a low tolerance (4%) to select the soild blue background, and it selects this bizzar pattern.  I can select multiple "strips" across the width of the image that all have this repeating pattern.  The color picker tool only returns RGB 0,0,255 and 1,1,255 thoughout the image.
And I can't just use the paint bucket tool to make it all one color, because it won't get the pixles in between my models ;-)
Eevee and Cycles give the same result, exporting the render as different image formats give the same result. I've tried changing the lighting, this does nothing which makes sence because it should be applied after rendering out the models.
Does anyone know what is causing the background of my render to have this slight difference in color?  It seems like all the pixles in the background should get set to the same value using this method.

The image appears to have some dithering applied, resulting in a less "solid" color. Although dithering can be useful in eliminating banding artifacts, it may not be helpful in your particular case. To determine if it is the cause of the issue, try setting the dithering to 0:

Thank you!  That was the issue!  It's almost comical that I set blender to output one solid background color, then dithering is applied and it tries to break up that one huge color band for a more "natural" look, when I'm trying for pixle-perfect.


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caustics cause way to high render time
I'm working on an archiviz scene, multiflat house with a little garden.
In the garden, I'm adding a small pool, created in a separate file and then imported in this.
During the pool creation, I played a little to set up caustics and I got a pretty good result, done in 5 minutes render in fullhd.
Now, in this scene, if caustics are activated, render time, from 10/12 minutes, render time goes up to 20-40 hours.
Is there any known bug by a chance?
Lorenzo

They're just very calculation heavy in an unbiased path tracer

i guess the issue here is that you have a much more complex scene between your lone pool and your full house with garden. If Blender tries to do caustics everywhere,that explains it. Maybe try to isolate your pool in a layer or even a scene and enable caustics only on that layer/scene and assemble everything in comp.


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How can I smooth out the edges in my object?
I wanted to make my own keychain as a project for school, I am also almost finished but when trying to bevel the outer edges there are multiple faces ontop of eachother on the part I extruded at the top.
I have used the bevel modifier before but in this case it won't work properly and I can't make the circle part first because then the edge between the two parts won't be smooth or it won't work at all.
I drew what I want to make poorly on the pictures below. The things I marked in the first picture is the bevel and the hole I haven't added yet and on the second picture I marked where I want to bevel it.
Any help and tips on how I can smooth the edges are appreciated!
Thank you in advance!

Hello, I'm not sure what you mean, are you trying to achieve the first shape (with the drawn corrections)? Maybe share your file so that we can try?

Hello, yes I'm trying to get the shape of the first picture, and want to smooth the edges I marked in the second picture.

you need to delete some faces, and in order to smooth the edges, bevel them?

I used the bevel modifier, so you say I just need to manually delete the not needed faces?

Yes but maybe share your file?

sure here it is: https://www.mediafire.com/file/110m6uz45y7l0sh/SA_BITCOIN.blend/file

is it what you're trying to achieve? https://zupimages.net/up/23/26/37y2.jpg

sort of but beveled so its smoother

like that? https://zupimages.net/up/23/26/e1dk.jpg

the edges are fine but I'm talking about the flat side to be beveld

do you have a reference image? it would help


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Automatic sound effect on bounce
Using physics simulation, I have created a ball bounce that looks something like this:

How can I automatically add a sound effect on each bounce?

The sound is from a provided sound file (example: Retro Jump 04.wav) and is not generated inside Blender.
It should be louder on the first bounce when velocity is higher on impact, and quieter as the velocity decreases.
It should also be quieter the farther away it is from the camera.
It needs to be automatic since I will have more than just one ball.
It does not need to be perfect. For example, if there are walls blocking the way, the walls can be ignored. Echo is not required.

Scripting to add sound strips on impact is acceptable.

nice description. But i don't see any effort you made to this. What did u try? Where did u fail? Do you know python? or r u just searching for someone who does the work for u for free?

@Chris I have added https://blender.stackexchange.com/q/301883/168154 on where I am stuck.


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Why does my cube not render in python
import bpy
bpy.app.debug = True
# Set the environment variable to indicate running in background mode
bpy.ops.wm.open_mainfile(filepath="/var/www/projects/render/cube.blend")
bpy.context.scene.render.filepath = "/var/www/projects/cdn/temps/cube.png"
bpy.ops.render.render(write_still=True)

# Reset the alpha mode to its original value
bpy.context.scene.render.film_transparent = origAlphaMode

the bpy.ops.render.render(write still=True) line
No addons are used its vanilla blender 3.0.1 and the Blender on my linux server is also 3.0.1 why is the most basic thing not running?
I am using a digital ocean droplet. Also I have used renderings on 2.79 for a long time with no issues.
Debug:
Blender 3.0.1
Color management: scene view "Filmic" not found, setting default "Standard".
/run/user/0/gvfs/ non-existent directory
Read blend: /var/www/projects/render/cube.blend
Color management: scene view "Filmic" not found, setting default "Standard".
Unable to open a display
Aborted (core dumped)
I really dont mind the other errors just the core dump is my priority.

Color management resetting from Filmic to "Standard" will mess the colors up a lot. How are you running the script? You should not run any code after bpy.ops.render.render(). Render is multi-threaded and may happen on multiple devices, python script does not 'know' when rendering is done and if you have code that tries to run after render is started you may get unexpected results. It would be better if you provided some more context. What you are trying to do here? Also why use such an outdated version?

How is this related to Linux server? Please provide full context.

@MartynasŽiemys Hey I dont even use filmic blender is being dumb and its relating to linux servers because Im running the python on it also idk if its colors it might be but I literally run bpy and it crashes every time it worked one time but now it doesnt work I dont use filmic I use standard but it forces filmic for some reason even if blender has it to standard and even if i change to filmic it says filmic is missing or something it makes no sense

@MartynasŽiemys Also its a grey cube even a basic render I changed it to standard im not getting color errors literally just goes unable to open display core dumped

Blender uses Filmic for years now. Is the file saved in 2.79? Make sure it works on your PC first. If you are trying to render with EEVEE, it might need a monitor connected to GPU for OpenGL rendering. Update to current version, it might be improved now. Also if you render on a server, I have no idea how you are trying to do that now, but you should probably try rendering from command line You can specify Python script to run if you need to modify something in the file form command line render.

@MartynasŽiemys no its the current blender for the cube

OK. Makes sense. Current version file will not work with 3.0.1.

Im trying to do a headless render on my server so it cant monitor also I already do that.. its bpy blender python which runs blender --background --python /link/to/py.py and the codes says the import bpy and all the codes to get it to run should I just change it to cycles lol

No.. the cube is using 3.0.1 sorry for confusion, I made sure that it matched up I meant latest package for linux

oh I think eevee doesnt work on bpy natively

Use snap install blender to update Blender to current version on your Linux server. Then make sure you use CLI rendering correctly. If you render from command line, you don't need to run render operator in a script. Might that be the problem?

It doesn't seem to be fixed yet. There seems to be a workaround worth checking out.


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why do merged videos become much large
I have five MP4 videos that I merge into one. The five files were about 50MB total, but when I merge them the file is ~250MB.  I'm using the same encoding, and medium quality output. Any idea why merging in blender quintuples the file size?
There are other questions on here about file size, but the answers all talk about changing the animation in some way, or using a different encoding.
I am just trying to merge MP4s and have the merged file about the same size as the input files combined.

I don't think blender explicitly let's you set the bitrate, other editors like resolve or shotcut will give you more control over quality settings.

You should be able to see in the file properties what the source files' bitrate is, just match up with the highest quality clip and it should be pretty close

@AllenSimpson, thank you, I will check that later to see if it fixes the problem, and edit the question once I do.


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Add bump to some part (the edge) of the procedural material
I was following this guide. Everything works as expected. But my final aim is to make this emission edges a bit different. I want them to be a bit heigher then other parts of the material like these chrome ornaments on this reference:

The best result that I could do looked like this. But it's not exactly what I want:

Here is my material:

So, I'm not really sure whether I chose the right track. I'm not even sure that something like this is possible :*) Help me, please, if possible <3

I don't think those metallic ornaments are made using a material (probably geometry nodes, but I'm not yet familiar with that aspect), and I doubt you can get a satisfactory result that way. (I'm also confused about the "emission" you mention, is that a misspelling?)

also i would recommend providing a link to that guide so that we know what you are talking about.

Well, the chrome parts are definitely not just bump - much too elevated, they are either displacement if done by some texture at all, but do not look like that, more like being real geometry put on there. But as the others said, I do not know what you mean with emission and I have no idea what "this guide" is either, maybe it would help to have a look at it.


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Problem with ALAMBIC animation and different shaders assigned to different vertex group
Here is the problem that I am facing :
export Alambic animation file from marvelous designer.
trying to assign specific shaders to different pieces of the fabric without going throught the UV way. > just want to add procedural shaders per specific items.
so far > I am able to do   VERTEX GROUPS selections and manually assign different shaders.
It's all good and working .
BUT ! . > and this is If I may say > a big but >
When I exit from EDIT MODE FACES.
The mesh goes BLANK MODE if i may say, like a BLANK SHADER "BY DEFAULT one". And I totally loose the benefits of creating those vertex group per farbric items .
here are 2 pictures showing the problem :

In advance, thank you very much.
Oops > I forgot to mention > This is happening on MOST RECENT VERSION of blender 4.2 beta. date 2024-07-08-19:36   hash : d527e3a6bd78    ... i will try on more "stable" 3.6.5 next..
yann

4.2 BETA is just that - a beta version and we can't help here. If you find it's ok in a previous Blender version I suggest you submit a bug report via the Help > Report a Bug menu in Blender so that it can be investigated before the release.

thank you very much for your feeback.   that is very true, and verified when I tried to perform the same operation in blender latest "OFFICIAL" 3.65   Hash cfleled46b7e date 23/10/16 14:30   >>> the described operation is working fine.

It might be an idea to try the 4.1.1 version before you submit a report just to make sure that the settings hadn't been changed when Blender 4 came out.

Thanks for the suggestion about trying in BLENDER 4.1.1.   just did it and it works totally fine. > I can't post a screen grab here any more apparently.    version of blender I did the test is :  Hash  e1743a0317bc    DATE : 2024-04-15  15:11

sinceres appologies for this useless report error message > now during those tests I realised that I probably did something very wrong >>> I was also testing the " REMOVAL OF FACES " on the alambic to save memory/space on the render. (me OVERTHINKING :)   > prior to do the shadin, all that Inisde blender 4.2 beta.   >> I must admit, to play with the NEW EVEE render...    big MISTAKE on my side ! >>  BECAUSE  I realised there the situation of the DIFFERENCE between EDIT MODE where the shader attribution of the FACE SELECT GROUP was working > BUT NOT later when IN   " OBJECT MODE ".

is the SAME in ALL VERSION OF BLENDER.   3.6.5,  4.1   4.2 beta. and evant 4.3 .  just test it again and again,  ervery version I go >> each time I want to delecte a faces > it corrupts somehow the ALAMBIC losing all knowledge of the vertex group...  >>  so I am creating a problem situation, and will avoid that in the futur ;))   my surprise is still there on the fact that in each version ;)) > in edit mode the shader attribution per FACES is still " working"  and goes "blank" when exiting this mode to object mode.   so >> this is problably a    NO PROBLEMO situation to report I assume ;)


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My video clip is playing in slow motion - I don't know why - Anyone experience this before?
I am new to Blender video editing - a rookie.  I have several video clips I want to edit together ultimately making a music video. For some unknown reason, when I drag a video clip into Blender, it plays in slow motion - no idea why. Not all of the clips do it. They were all shot on the same camcorder. The ones playing in slow motion still play at the normal rate in VLC Media Player, so I know the original is fine. Has anyone else experienced this? I'm wondering if I accidentally hit something that changed the speed of this video in Blender...

Often times Blender playback is slowed down because of lack of resources in either complex scenes or in VSE with larger video files. Is it generally not reaching the fps when you want to edit this clip alone or is this clip slow at the same time together with other clips playing at normal speed?

you might wanna make sure that Blender's fps is set to the same speed as your footage (ie: if you pop a 60fps clip in, and your blender project is set to 24fps, it will play at less than half its real speed)

Thank you - I was wondering about frame rate and the example you used is exactly what's happening. Video clips I have recorded play fine in VLC media player but when I pull it into Blender, it is less than half speed. I will further explore this. Thanks again!


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How to make the same thickness for an object with different thickness?
there is an object with different thickness, thicker on top, thinner on the bottom, but the thickness is not symmetrical, how to make the entire thickness of the object the same, to reset it roughly

I guess you need to select a side and SY0 (or SX0) and same thing for the other side

... on top of that, you should care the topology, that seems to be a source of issues (https://imgur.com/WHDaZzM)


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Geometry Nodes - Sample unit scale
Pretty much as the title states, I would like to sample file unit scale inside geo nodes. This is to foolproof my node setup if shared with other users. Is there any way to do this?

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

Do you mean Scene - Units - Unit Scale?

Yes that's right, I would like to sample Scene Units Scale to accurately project object thickness regardless of scene units denomination used (1 or .01).

I don't know a way to do it in geometry nodes directly. But there is probably a way by using a script and maybe a way to pass it as a parameter to the node. Anyways, I don't think, that these options are what you are looking for, when you want to make it foolproof for your users.


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Sculpting problem in edit mode
I can't see my sculpt in edit mode but it gets displayed in object mode and sculpt mode.

You don't give us any information on how you sculpted the mesh and what kind of modifier you use - so I will ask my crystal ball ;) You have a Multires modifier on the object to create enough geometry to sculpt. But it is a modifier, the resolution is procedural and the sculpt only built upon this virtual mesh as long as you don't apply the modifier. The Edit Mode always shows the existing geometry, which is still a lower resolution and not sculpted.

how can I fix it?

You could also use Shape > Apply Base in the modifier so that the base mesh will be deformed according to the sculpt - but when the base mesh has a lower resolution this will not be the same as the sculpt. If you really need to see the sculpt in Edit Mode for whatever reason, you have to apply the modifier. But then the change is permanent and you cannot simply go back to a lower resolution.

A common workflow is to use the remesh operation ('Cltr+R') to model the basic shape of the model (use the 'R' key in Blender 3.5 / 'Shift+R' in earlier versions to visually set the Voxel Size value). When you're happy with the basic shape, you can do a retopology to create a low-poly mesh version of the model. Then add a MultiRes modifier and add finer details like wrinkles, scales, etc. Finally, you can bake a Normal Map from the MultiRes sculpt and use it for the low-poly base mesh.

Have a look here: https://www.youtube.com/watch?v=tQfFlzHJJ88 (Dino creature) or here (Grant Abbitt's Old Man) (uses DynTopo instead of remesh in the first step). -- If you're looking for sculpting human anatomy have a look here: https://youtu.be/L5i6SM07DHk (there are several free videos in this channel about female and male heads, body, legs, etc) and https://youtu.be/Sbj-SSdaA_Y

Is it selected?


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Why are Vertices of Plane createt by list of vertices are changing Position when the plane is rotated around the Z axis?

I have the following Problem. The planes you can see here are created with lists of vertices. If you rotate these Planes the vertices "jump" so to speak. I don't know why this is happening. Here is a snippet of my code :
with open(fp) as f:
 json_string = json.load(f)
 with open(lp) as l:
     layer = json.load(l)
 with open(sp) as s:
     static_passes = json.load(s)
 for i, row in enumerate(json_string):
    verts = [(row[0][0], row[0][1], 0), (row[1][0], row[1][1], 0), (row[2][0], row[2][1], 0), (row[3][0], row[3][1], 0)]
    faces = [(0,1,2,3)]
    edges = []
    mesh = bpy.data.meshes.new("Plane")
    object = bpy.data.objects.new("Plane", mesh)

    mesh.from_pydata(verts, edges, faces)

The problem is likely unrelated to your Python code. You have some planes in the background and probably snapping enabled.

Looks like a floating point precision problem. Are your coordinates very far from origin ?

@Gorgious yes they are far from the origin. I try to change that.

Simplest way to go in object mode : Right click > set origin > to geometry. Then ALT +G to reset the location


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Fluid simulation on FBX file to three.js but animations are not showing! (How to make fluid simulation running on three.js)
I'm new to Blender, and I'm struggling for days on this fluid simulation.
I have made a fluid simulation that goes well in blender, but it doesn't animated when I try to load the animation through FBX file using Three js.
I assume that my fluid simulation IS NOT SAVED because when I load my FBX file through the blender, all the fluid simulations I baked in the previous file is gone.
Here's my blender file: https://drive.google.com/file/d/1mfIkt0MNRpwBTxYjsX4pgXCAfIaZB7yR/view?usp=sharing
And Here's my javascript:
import * as THREE from 'three';
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js';
import { GLTFLoader } from 'three/examples/jsm/loaders/GLTFLoader';
import { FBXLoader } from 'three/examples/jsm/loaders/FBXLoader';

let camera, scene, renderer

const clock = new THREE.Clock();

let mixer;

init();
animate();

function init() {

    const container = document.getElementById('canvas');
    document.body.appendChild( container );

    camera = new THREE.PerspectiveCamera(70, window.innerWidth/window.innerHeight, 2, 2000);
    camera.position.set(0, 10, 30);

    scene = new THREE.Scene();

    // model
    let loader = new FBXLoader();
    loader.load( '../static/assets/martini.fbx', function ( object ) {

        mixer = new THREE.AnimationMixer( object );

        let action = mixer.clipAction( object.animations[ 3 ] );
        action.play();

        object.traverse( function ( child ) {

            if ( child.isMesh ) {

                child.castShadow = true;
                child.receiveShadow = true;

            }

        } );
        object.scale.set(0.01, 0.01, 0.01)
        scene.add( object );

    } );

    renderer = new THREE.WebGLRenderer( { alpha: true } );
    renderer.setPixelRatio( window.devicePixelRatio );
    renderer.setSize( window.innerWidth, window.innerHeight );
    container.appendChild( renderer.domElement );

    const controls = new OrbitControls(camera, renderer.domElement);

    controls.update();
}

//

function animate() {

    requestAnimationFrame( animate );

    const delta = clock.getDelta();

    if ( mixer ) {
        mixer.update( delta );
    }

    renderer.render( scene, camera );

    // stats.update();

}

And My current output is so static... I want to make a fluid animation running in Three js.

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

@DuarteFarrajotaRamos Thanks for the link! I figured out that it is hard to export fluid simulations to three js...


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How do i make a brick wall?
I'm kinda new to blender and I'm trying to replicate a living room for studying reasons.
https://i.sstatic.net/rZkD0.jpg
The wall in question lies in the right side of the room along with some windows and I do have a PBR material that fits my needs.
https://i.sstatic.net/r2mrs.jpg (texture I'm trying to use)
I've tried a bunch of stuff, but none worked the way I thought it would. I tried using modifiers subdivision surface + displace with texture I mentioned above and I created a material along with the provided textures, but the material was too flat for my liking and I was having a really hard time unwrapping the mesh and in the end it became a mess.

How to upload an image to a post

If making flat walls, a good set of PBR textures should be enough. For more complex brick work (archways, rounded structures, etc), you might want to create a particle system of brick objects. You can use both techniques together, texturing the particle bricks to match (using the same PBR textures). If you have to cover really large walls, breaking up the texture uniformity can present a challenge, but there are ways around this such as cutting and rearranging chunks of the (already UV mapped) wall geometry, or peppering particle bricks over the textured wall in strategic spots.

The quality of the PBR material that you are using is quite poor if the image you uploaded is what you're using. I would try something along these lines:

These were found on the popular site Poliigon.
You can probably get away with only using the normal maps and displacement.
As far as unwrapping, I'm not sure what you have to unwrap exactly. It's a wall... just unwrap it like you would any other rectangular object and try to hide seams where possible.


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! Going Back in Blender Project History?
I think I may have lost a lot of my work but I'm hoping someone here can help me find a way to recover it.
I'm working on an animation project where when I make a new scene I usually make a copy of one of my existing scenes that has the models I created already in it and use it as a template for the new scene so that I don't have to recreate or append my models.
I usually take an existing scene, make a copy using "Save As" with a new file name for the new scene and then delete all the previous keyframes to get a clean slate, but still have all my models.
However, in my most recent session, I realized that I had actually forgotten to first make a copy of my original scene by using Save As and so had just deleted my original project, which represented a lot of work. I'm been looking around to see if there is a way to go back to my original file or go back in my project history so I can restore my original file but can't find a way to do this.
Is there a way to see my Blender projects history? I just need to be able to go back to the original file before I made all my changes. Is there a way to do this?

You may have an autosave of when you last quit, you can check in this menu.

@blasterfish Or try to check .blend1 file https://blender.stackexchange.com/a/14463/2214

Oh this is true.  I've disabled this because I can go back file versions in a lot of cases.


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Alpha - Image Texture problem

Hello, I am designing low quality alpha hair for a character I created, and when I use image texture on the meshes I made in blender, I encounter such an image. The texture does not appear as it should. Transparent and small details are completely erased. It looks noisy. What is the reason of this?
When I look at the same process in the 3D part of Photoshop, the result looks perfect. I want my texture to look like it does in photoshop.
How can I solve this problem?
The first two images are from blender. The last one is from Photoshop :

Maybe check the Image Texture settings, like choose Closest instead of Linear? Or pack your images and share your file so that we can check?

there is a lot of information missing. You seem to use Cycles as preview engine. How does it look like in EEVEE? Does the result change whenn you increase the samples setting of Cycles?

Be aware there is a separate samples setting for preview render. Have you tried an actual render? What does it look like?

It looks like you have a separate plane on top of the head, and therefore some rays are going through the transparency, some don't, but if you get just one sample per pixel, you will get a dithering, where a pixel has either hair color or body color, with probability based on alpha. You need at least two samples per pixel for SOME pixels to be an average: but with 2 samples you only support 50% alpha, when one sample hits the body, and the other hits the hair, and due to randomness involved you are not guaranteed the 50% alpha won't get two samples hitting hair or 2 samples hitting the body…

if you share your file: How to upload a blend file on BSE - good practices and advice we might suggest how to do it better, that is, calculate the color once, on a single object, requiring just one sample per pixel (at least for this effect, other things like lightning, reflections, soft silhouette etc. require more samples still)

Guys, really thank you for your answers! I'm new to this so I couldn't understand a lot of what you said... Hahah sorry! I think I need to start all over again with a good tutorial.
Is there a nice and simple tutorial you can recommend for what I want to do, which I think can be called Alpha Hair design? What I find on YouTube is a bit challenging for me...

This is exactly what I'm trying to do. However, I think the program used in this video is not Blender. It looks like 3ds max. The texture he added to the meshes looks very clear. Link : https://www.youtube.com/watch?v=_kR4sXeOLKw&t=159s

Please share your file so that we can check it, make sure that you've packed your image (File > External Data > Pack Resources)


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Blend mode ‘Darken’ in Mix RGB node is showing different color
I'm following this tutorial where he explains how the Mix RGB node works, and to better understand, I'm trying to replicate his steps. What I don't understand is why I'm not getting the same color as him despite having the same settings? My only thought is that I'm doing something fundamentally wrong, or perhaps the blend modes of the Mix RGB node have been updated? I'm hoping someone can help me figure this out.
Link with timestamp: https://youtu.be/91UDQnrZMqA?t=196
Printscreen:

You've plugged your Mix Color into a Principlded BSDF, while in the tuto he probably plugs it directly into the Output, the Principled BSDF will add some effects, mainly specularity (the surface reflects the lights and environment and therefore the color looks brighter than you think), lower it down to 0 and you'll have the same as in the video.

Oh, of course! Thank you!


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Question on scaling object and its impact on rendering in Cycles
I am modeling a plastic bottle. The plastic bottle is actually 19 mm and 6 mm. However, when I modeled it in that size, I encountered issues with clipping and auto-merging vertices. Instead I worked in centimeters.
My question now is: how does this affect Camera and the rendering, and how does Cycles calculate things? Is it crucial for me to scale everything to the correct size, or can it work since it's relative?

Hi :). It's generally easier to have the final render in real world size, so that depth of field and light falloff will be correct.

In general you can say, the rendering is affected by the dimensions. If you take a Point lamp and set a Power of for example 100 W then this might give some realistic light strength if you put it in a room with an area of 4 × 5 m. But due to light falloff, the same lamp will be very dim if you modeled the room in a scale of 100:1 and now it is 400 × 500 m.
Not only renderings are affected, but simulations as well like rigid bodies, soft bodies, cloth, smoke and fluid etc. But sometimes the simulations work better if objects have certain sizes, therefore people sometimes the change speed to make the simulation faster or slower depending on what looks more realistic.
About the Auto Merge: first of all you could disable it so that this does not happen even when working on small scales. Although it is sometimes neat if you do not have to merge vertices manually and can help preventing to accidentally have duplicates sometimes, it has the potential danger of messing up objects when vertices are unintentionally merged unnoticed, especially when merge thresholds are too large.
The clipping is only affected by the scale in so far that you can set distances for Clip Start and End, separate for the 3D Viewport in the sidepanel under the View and also for cameras in their Camera Properties. If the model is so small that in order to see it you need to get very close below the clip start distance, it gets clipped. If it's so big that you need to view it from very far away outside the clip end distance, you get the same problem.
So it is not necessary for clipping to model at real world dimensions like for shading or simulations, since you can adjust the clipping as needed - of course you can get away with unreal scales in render or simulation as well if you tweak the settings to a certain degree, it just makes it easier to get something looking realistic if you model it in its correct size.
The most important when changing the clipping is to have a range that is not too wide. For example a start of 0.01 m with an end of 100 or 1000 m is okay, but not 0.001 m and 100000 m. Although 0.01 might already be too large for your small model, so a start of 0.001 m is probably better.

Thank you so much!

Hi again! Just a quick question on not setting the clipping range to wide. Is there any particular reason for that?

@N03 Sure. It is mostly a matter of floating point precision and hardware limitations. If I have for example values like 0.00001 (10$^{-5}$) and 10,000 (10$^{4}$) this is a factor of 10$^{9}$ from start to end. This will result in artifacts because the calculation of faces and their view distance order gets messed up, like in this example with a 40 m high Suzanne and the above clipping values: wide clip range It might even look worse when zooming further out: zoomed out, sometimes the object might even disappear.

@N03  Of course these artifacts can be very annoying when trying to model and make it much harder to see what you are doing. But since the object is quite large, there is most likely no need to set the Clip Start so very low because you might not need to get so close, so you could set it higher to 0.1 for example. This already looks much better. And maybe you could set the End value lower as well, if you are not going to zoom very far out. So here is how Suzanne looks with a smaller clipping range: clip range adjusted.

By the way, not only the range from Start to End overall can be problematic, it seems that very low values for the Start are generally producing more artifacts in perspective view, whereas very high End values are producing more artifacts in orthographic view. Read more about the topic in the Blender manual: Depth Buffer Glitches

Thank you Gordon!


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Can I change middle click to Pan?
I'd like to swap the controls for pan and orbit essentially so it's like AutoCAD where middle mouse click goes to pan and shift middle click is orbit. Where's the best place to suggest this as a feature add?

Are you trying to customize it yourself or learn where feature requests are posted?

You can configure this in User Preferences > Keymap (Input in 2.7x); just set the shortcuts for view3d.rotate and view3d.move accordingly:

Exactly what I was looking for, thanks so much!

I can't find this in Blender 2.8.

Never mind - found it - under Keymap


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Cycles Render, Looks wrong in Render ViewPort, correct in Material ViewPort
Using Cycles Render! Have tried things for hours on end and can't figure it out, please help!
I simply want to bake the texture from the Material Viewport, but it continues to bake the looks of the Render Viewport. Why is Render Viewport so extremely different looking?

Material viewport is approximation, it can't be used as reference point for results of baking certain pass. Note also that network of nodes results only in Diffuse shader and ColorRamp node connected right into Mix shader node (which is incorrect since output of ColorRamp is color not shader). It's not clear which pass are you trying to bake though

Thanks for the response. Is there any way to texture Bake the "active viewport" similarly to the openGL render active viewport option, but instead of a viewport unwrap it to the texture UVs to be saved as an image, such as in a texture Bake? Thanks!

No, generally there isn't. Instead I would advise to go with standard rendered shading. For speeding it up use Node Wrangler addon and Ctrl+Shift+left click on nodes to get their current preview on the model. It would be probably possible to go with your existing result if fixing the node setup as mentioned before (ColorRamp should not go to shader input) and baking resulting nodes into texture


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T POSE CLOTHING PROBLEM
I am trying to apply a T posed mesh Top to a somewhat different T posed static mesh. It is a mesh for Sims 3 and I am saying that because even though I have managed to make the cloth hug the model without any deformations by adding an armature, in the end in order for the armature to bone/auto weight on the clothing part, altered some things on the mesh which is problematic for the texture. I don't know where this data of which parts are mirrored and which aren't is, and it resulted in the texture to follow a mirror path throughout the whole mesh and not exclude the individual parts (f.e. big armlet on the L side). So I am trying to find another way to make the top hug the model. Also I have to add that I don't know after many errors and tries and managed to bind the armature with the top because I had the Heat weight bone problem. I tried deleting doubles but that just drops the quality of the top a lot. And doing the seperate loose parts gives me around 900 seperated parts which is also not good. Can someone help me? thank you.

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

Yeah of course


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How do I UV unwrap a half sphere?

Hello, I am a beginner in Blender and I have tried to make a ladybug for my project. I managed to model it, but now I have to add a ladybug texture to it. I heard that by using the "Smart UV Project" function, I can easily   add my Ladybug pattern to it. However, after doing this, my image started to distort. Now as you can see, the ladybug's patterns has gone really wrong and I don't know how to fix it, so is there any way I can fix this problem and make my ladybug work?

You have a lot of polygons there! That's going to make UV unwrapping a little harder. Try opening your texture image in your UV/Image editor viewport (Image->Open Image), and it will show you how your geometry lines up with the picture. Then you can move those verts around to change how the image lines up with the model. You can also export the UV layout to an image (UVs->Exoprt UV Layout) - this gives you a pattern to draw your texture over, like a coloring book.

Use the primitive's default UV map
It looks like it might not take too long to remodel your bug...
When a new primitive is added there is the option to create the default UV map.

Then tab into edit mode and selecting all, switching to UV editor layout

This was a really quick effort, with all the UV selected and scaled by eye to match the texture image as in question. (eg without rotating image lol)
The nature of the default mapping is equirectangular  360 degrees longitude "U" by 180 degrees latitude (2 x 1) "V".  Will be best at the equator and worst at the poles.

Image from the wiki Equirectangular Projection. showing how dots are distorted toward the pole.

as an image to default UVMap, see how they are now all dots
A black line across top of image would translate to black dot on pole, similarly to how (ant)arctic circles appear across the top and bottom of world map
For half a sphere, delete a half of sphere.

It will be hard to have perfect circles on your ladybug this way. You could do it several other ways, but here are 3 ways to do it:
1) DIRECT PAINTING

Unwrap your semi-sphere in Blender.
Prepare a red image texture in the UV/Image Editor
Plug the Image Texture node with your image in a Diffuse (and plug the Diffuse in the Output).
In the 3D View window, switch to Texture Paint mode and paint your black dots with a very steep curve brush.

2) PAINT A MASK

Unwrap your semi-sphere in Blender.
Create a 100% white texture and plug it in a Diffuse (and plug the Diffuse in the Output).
In the 3D View window, switch to Texture Paint mode and paint your black dots with a very steep curve brush.
Now change your node organization and use your texture as a factor in a mix between 2 Diffuse nodes: one black and one red.

3) TRANSFORM A PLANE INTO A SPHERE
You could also create a plane, map your pattern on it, transform it into a sphere with some Simple Deform modifiers / Bend mode, then cut the sphere in half: How to animate morphing a rectangular plane into a sphere

yes you're right, I'm going to edit  ;)


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Stacking UV-island on top of each other
I have a quick question. I'm asking just in case so I won't get in trouble further down the line. I'm texturing a model, and it's only for rendering an image of it with some render passes. I'm stacking the UV islands on top of each other, and I'm wondering if that can cause some problems? I am unsure if it might create any issues for me or if it's better to work in a different way? I hope you can provide me with an answer here.
Thanks in advance.

As already said in the answer, this should cause no problem if you don't need it for baking. It makes totally sense to overlap UVs, let's say you have an image with a logo, and this should appear multiple times on a certain object. It is a total waste of resources if you want a high resolution logo and need a gigantic image texture just because you need to place the highres logo a dozen times on it so that there is enough space between them to keep the UVs non-overlapping.

Overlapping UV islands is not a new technique. It has advantages like reducing the overall memory requirement for the scene. If the repetition of the texture is not an issue, this technique should work fine. If you're creating the asset for games, you need to be aware that overlapping UVs are not going to work in light baking. Typically, a second non-overlapping UV map is created for that.

Thank you for your answer! It's not for a game, so I won't be baking the texture. I will only render it with render passes :)
What is the technique called if I may ask?

When you stack UV islands, it creates overlapping UVs. That's the name as far as I know. When you make the UVs in such a way that they never stack, they will be described as non-overlapping UVs.

Thank you so much!

You're welcome!


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Gradient light with Area light
I have just learned how to create a plan and make an emission of it, then create a gradient to control the light as I want. I was then advised that it should be possible to use nodes in an area light.
However, what I can't figure out is how I can, for example, see how my gradient looks (such as on my plane) when I apply the same principle to an area light?

Since lights have no directly visible geometry per-se the effects are only visible through the light effect on the scene (through diffuse influence, shadows, reflections etc.). If you require them to be visible, you are better off with an actual plane. Alternatively you can use the same node group on both a light and a plane to see the effect

@DuarteFarrajotaRamos In Cycles you can turn on visibility for lights in a way, see answer.

To make the Area light visible for the camera, go to the Object Properties and under Visibility > Ray Visibility enable Camera. This option is turned on by default for "normal" objects like mesh objects, but by default turned off for light objects. Note that it is only visible if the light is directed (at least partially) towards the camera - this goes for spot and area lights, point lights can be seen from any angle and sun lights look very weird. And it only works in Cycles, I do not know if there is an equivalent in EEVEE.

Nice one, wasn't aware of that

Thank you so much!!


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Create your own texuture from image
I have a large image that I want to turn into a texture, with roughness and a normal map.
I've never done this before and am wondering what methods are available and if there's a preferred approach?
I would be very grateful for tips!

You have some softwares that do that, also some websites, but the result will also depend on your texture, for example if the lighting and shadows are not correct it won't work fine, how does your texture look like?

What software would you recommend? I can share you the texture if you message me?

You can convert an image to a normal map, but the result will depend on the lighting you have, if its low angle it won't be interpreted correctly of course as dark is supposed to be hollows and white is supposed to be heights...
You can do it with Photopea for example (it's an online version of Photoshop), open the image and Filter > 3D > Normal Map (put a bit of Blur), then File > Export As > PNG.
You can also do it with Krita, Normalmap Online, etc...
As for the Roughness, if black parts are supposed to be rough and white glossy, just plug the image texture into the Roughness input of the Principled BSDF, the values of the image will be interpreted as 0 to 1 values. You could also blur a bit the image in an image editor if you want to avoid too sharp edges.

Thank you so much!


text:
UV unwrap, tick box: Use subdivision surface
A quick question,
When I UV unwrap, I can choose "Use subdivision surface." in the box
I'm using Subdivision Surface (which I haven't applied to the model).
I don't understand what it does. But the result is better.

As stated in the manual : "Map UVs taking vertex position after Subdivision Surface Modifier into account." https://docs.blender.org/manual/en/2.79/editors/uv_image/uv/editing/unwrapping/mapping_types.html

Could you please clarify the meaning

@N03 I'll prepare an answer to show it.

Thank you so much!

To explain what this means: let's say I have this not so great model which is quite low poly and I have a Subdivision Surface modifier on it to make it more smooth. I also put some seams on it for UV unwrapping. I just focus on the faces of this one side view to show the effect.
If I simply unwrap it without the Use Subdivision Surface option, the unwrapped faces are shaped more or less like the original low poly mesh:

But if you enable the option, the UV unwrapping will take the change of the overall shape due to the Subdivision Surface modifier into account. Of course the UVs still just have the low poly mesh so they are not as rounded as the subdivided version, but they are matching a bit more (here I have enabled to show the effect of the modifier in Edit Mode so that you can see the deformation better):

Below I have traced the outlines of the UVs and laid them over the model to show the difference better. What this can be useful for is take into account that textures that use the UV map to be placed on an object are less distorted when the Subdivision Surface modifier smoothes the mesh. When the mesh is not so extremely low poly, the result might be even better.
If in the example below when you place a logo or text etc. on the side of the object mapped to the left UVs, then the result on the subdivided object will be squashed more than when using the UVs on the right.

How much this option has an effect on the UV map, how good or bad the result for your model will be etc. of course depends a lot on the model itself, the unwrapping process, the seams, just like normal unwrapping there are a lot of variables taken into account when it comes to good or bad UV texturing.
Another example, this time comparing the effect of Use Subdivision Surface with some logo on the side of the object. While on the left without the option enabled, the logo is squashed vertically (the yellow part is supposed to the a circle), it looks a lot better on the right although not perfect due to the very low poly base mesh.

Thanks for your explanation. I feel like I've got a solid grasp now! :)

@N03 I just added a "real" example with a texture at the end to show (one of) the uses cases for this. Basically you can of course tweak UVs manually to reduce the distortion of textures, but this option helps reducing the need to or the amount of work manually.


text:
Objects are falling outside instead of inside when using rigid body
I have a text converted into a mesh. I want a bunch of cones to fall into the hole in the text. When I use rigid body, all the cones end up outside the text instead of inside. How can I get them to collect inside the text?
What I'm trying to do is to fill a logo with objects, like lots of cones. The logo is extruded but has no top face. They should then lie still in the logo, just looking natural.
The file:

Check your face orientation:

Blue is good, red is bad.

Select all cones
Press Tab to change to Edit Mode
Press A to select all
Press Shift+N to recalculate normals
In Object Mode select all cones, choose Object > Set Origin > Origin to Geometry
Select your text and all cones, then press S, type 100, press Ctrl+A > Apply Scale

The scale of your objects was ridiculous low. Blender simulations don't like "wrong" or extreme scales.
The result:

I flipped the normals but the cones ends up outside the text instead of inside still!

Thank you!! What are ideal scales for Blender simulations?

"normal" sizes for rigid bodies. So like the default cube. For cloth better 10x or 20x of that size.


text:
Remove top Faces still using curves, is it possible?
I have a logo in .svg format that I imported into Blender. I've extruded the text upwards. However, I would like to know if it's possible to remove the top face of the logo. Is this doable while working with Curves, or do I need to convert the Curves to a mesh?
The file:

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

I don't understand. Do you want me to explain in more detail? :)

No need, just add a few screenshot images showing your model and your settings

You can change the Fill Mode option, choose Back if you want to remove the top faces:

Thanks!! This is what I wanted!


text:
Add Bevel to curves when using a solidify modifier for thickness on a imported .svg logo
I have an imported logo .svg file that is in curves. I have eliminated the top faces by using Fill mode: Back.
I now want to add thickness inside the logo itself, so I have used a solidify modifier.
My question is how to add a bevel to this thickness.
I tried using Bevel in Curves in the data properties, but that gives me artifacts on the model. Is there another way to add the bevel, or a better way to thickness without solidify modifier?
The file:

(Using Blender 3.6.8)
A Bevel modifier can be added after the Solidify modifier, unchecking the Clamp Overlap limiter that is probably confused by such a small geometry:

Resources:

Side note: May I recommend to scale up your objects, or to change the "Length" parameter in the "Scene/Units" panel to "Millimeters", to avoid such small numbers to edit (and to adjust...) ?

Yeah, I get alot of clipping :)

Thank you by the way, I didn't get the bevel to work, but when I looked at your settings I had Clamp Overlap. So many thanks to you! :)


text:
Fluid animation, object which holds generated fluid
I'm working with fluid animation and i struggle with one thing. I want my cup to hold the fluid that came from object which is set to Type: flow, Flow type: inflow. I've tried to set the cup to be effector and guide but that doesnt work i've also tried to set the cup to be domain, but fluid doesnt rly want to exists outside the domain to that doesnt work as well  :<. I read somewhere that effector has to have some thinckness to i add a solidy modifer, but that doesnt change anything.

Look if this may answer your question as well I am trying to fill a bottle with liquid. I wrote the answer, so i believe i can say it should cover what you may need. In your case just think of the bottle as a cup, if you only have the bottom part of the bottle, it's pretty much a cup ;) And yes it needs a thickness.

Thank you <3 one question more tho, do you know how to fill a bottle/cup with exact amount of liquid, using inflow? ( ik i can use copy of geometry of a cup, but it wont look like its pouring from teapot)

I believe there you may need to use the "Replay" mode and adjust the length of the time the inflow is active and or the size of the teapod-spout (opening where the tea comes out from) aka the sphere of the inflow.


text:
Weird Texture paiting glich
i was texture paiting donut and some weird glitches happened:   this pattern isnt dissapearing when i paint it down again.

It would help if you could show the UV-map, as i believe there might be some problem with that.

https://gyazo.com/f0573eb33a2815c35dff89d91f50d07e
Yes indeed sth wrong, but i cant delet those vertices on the map

You can't delete vertices in the UV-Map, as they represent those from the mesh, but i'd suggest to select an edge loop along the outer middle marked a seam and maybe one on the inside. Then uv-unwrap and you should have a clean UV-Map and can paint without the weird issue.

Yes that indeed helped, i forgot to respond. I've done whole sceen :)
https://gyazo.com/662705ca1a48e8689539386f54812fc7

Glad it helped and you have one nice project under your belt, i know it feels good to finish a project, congrats ;)


text:
Trouble with point visibility at boolean intersection edge with Geo-nodes. Trying to make a disintegration effect
Im trying to make a disintegration effect using geo nodes. My plan is that when my boolean intersects the plane, particles appear at the intersection. My problem now is that when I’m trying to make the point only visible right at the edge of the plane where my boolean intersects it, I can’t get it to work. (Less than is set to 0.001) What could be causing this?

The file:

assuming that this...

...is what you want, you can use this node setup:

Note 1: always try to avoid boolean nodes, because they make your node tree slow. So use proximity whenever it is possible.
Note 2: Delete the link i marked with the blue x -> i just wanted to show the plane so that you can better see how it works.
With the proximity to faces, i get a distance to the surface. With the greater than node, i can delete all distributed points on my object, so that only points near the surface stay on it.
Hope that helps.

Not on a PC right now: could you also use the proximity for the Density of the Distribute Points on Faces node instead of deleting generated points? Like for example distance < 0.001 and multiplying the result with 800?

Thats a really good idea!

@GordonBrinkmann: i didn't try either, but i assume: yes

Also thank you for the solution! Chris


text:
Help with 3D Axe Model - Issue with Materials
I've recently created a 3D model of an axe as one object. I'm using texture maps for the material, but I'm having a problem with the cutting edge part of the axe.
I want the edge between the cutting edge part of the axe and the head of the axe to have a soft transition in between.
When adding two different materials, one for the axe head and one for the cutting edge I get a sharp edge where the materials meet. (See images attached)
If I instead combine these two materials as one and separate them with nodes I’ll get a soft transition but the cutting edge material becomes a straight line instead of a curved line.
I would like to have the cutting edge material curved with a soft transition and was wondering if anyone has any tips or suggestions for how to solve this.
Any advice would be greatly appreciated! I’ve added print screens as well.
Thank you in advance for your help.

Hello what does it give if you use the UV output of the Texture Coordinate? Or please pack your images and share your file?

Hello. Have you tried using a texture map insted of using generated coordinates to separate both shaders ? Use black and white values dpending on where you want the edge to be

As gorgious commented, a good way out is to use UV coordinates for the transition rather than generated. The UV map for the side of the axe head should be a normal rectangle, so that the straight gradient will bend along the cutting edge. Note that you may want to set up other UV maps for the other textures used in this material. You can manage UV maps in the UV maps panel of the Mesh tab of the Properties editor.


text:
Clarification on node setup when applying surface imperfection
I'm trying to understand shading and nodes and would appreciate it if someone could just confirm that I have understood correctly, and I also have a question.
Currently, I am experimenting with adding surface imperfections and following this example:
Link: https://cdn2.cgbookcase.cloud/textures/guides/blender/surface%20imperfections/dirt_setup.jpg
My question is, what is the purpose of the value node in the example?
If I understand correctly, Color 1/A should be my roughness map, and completely black should mean no roughness, and vice versa if I want roughness, it should be completely white.
With Fac set to 0, only Color1/A is present. Fac set to 1 becomes A+B with Screen.
But in the example, what is the purpose of the value node that is used? Is it simply setting the Value to 0.03 in HSV? So if I have 0.03 in Value in HSV, will I get the same result as with the Value node?"

If it is not used as a driver for some field, it has absolutely no use because it is not plugged in anywhere.

Its plugged into in the example I was following: https://cdn2.cgbookcase.cloud/textures/guides/blender/surface%20imperfections/dirt_setup.jpg In my picture if have disconnected it and used a value instead.

Well, when asking if it is of any use you should show a screenshot where it is actually in use. In this case, plugging a float into a vector input (a color input is like a vector) will set the float in all three channels. So with RGB having all the same float, it is basically as you suspect, creating an RGB color with (0.03, 0.03, 0.03) which corresponds to an HSV color with a saturation of 0 and a value of 0.03

Thanks. Could you clarify what a float is, and I though Vector was a Normal. But im new to this, so could you help to explain that?

These are not Blender-specific terms. Generally, a float is a single decimal number (a scalar), vectors are quantities which cannot be expressed by a single scalar, like normals or directions etc., they can be expressed by an $n$-dimensional vector, where $n$ is the number of scalars they contain. In Blender vectors are usually 3-dimensional, holding an X, Y and Z value. But RGB colors are 3-dimensional vectors, too, only that you call the dimensions here R, G and B. That's just a quick explanation, not meant to be mathematically 100% accurately phrased but hopefully you get the idea.

By the way, the Screen mode in the Color Mix node does not become $A+B$ when you set the mix factor to 1, it becomes $1-(1-B)(1-A)$, because the formula is $$1-((1-Fac)+Fac\cdot (1-B))\cdot (1-A)$$ which means, it will only be the same as $A+B$ when one or both values are 0.

Im not quite sure I understand what you mean, could you explain it in a easier manner?

Let us continue this discussion in chat.


text:
How to remove these strange lines?

When I coloured the texture with "F Fill" tool, then these strange lines appeared.
I tried to remove them desperately but they never disappear.

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

It's easy. Your UV map islands overlap with each other, and with the image border. Consider using some gaps for your UV map. Also you can use some bleeding in the paint Options tab to extend filling even more.
Also ensure if the 'Subdivide UVs' in the subdiv modifier is checked.
And also you can disable subdiv modifier when you paint the texture. The paint mode considers subdivided UVs, hence it keeps some edges uncovered.

Also, to get rid of them right now - you can set your UV/2D Image Editor to 'paint' and use the fill tool there, set the thresh hold high so that you can drop the fill there into the black pixels of the image editor.


text:
Trigger particle emission on collision with another particle system
I have a particle system A whose particles have been already emitted.
Now when these particles collide with Particle Emitter B, I want B to start emitting particles.
How should I go about doing this?


text:
Is there way bevel inside corner?
Trying to bevel inside corner without adding extra edges.

Is there a better way bevel corner without adding extra edges? On the example below having extra edges is not a problem but some other situation needed to have fewer edges as possible. Trying to avoid Ngon.

https://topologyguides.com/post/126426510380/sub-d-corner-types-click-to-see-high-res


text:
How can I selectively change custom split normals in python
Using 2.80. I have a solution how to get the wanted loops via the bmesh faces. I can set all split normals at ones with normals_split_custom_set. But for this to work I need to read the old normals so that they will go unchanged when I overwrite them. How can I do this? Is there a better way?


text:
Make a transparent background of texture w/o Principle BSDF shader
I have some textures already made; all I need is to know how to make that texture, when put on objects, to have a completely transparent background. The problem is I need to do that without the use of the Principle BSDF shader as that makes any object it’s attached to have shading, and for the retro style I’m working with shading is something I’m avoiding entirely. Unfortunately every video tutorial shows transparency only working with that aforementioned Principle shader, and fiddling around with transparency without it does work in cutting out the background but the texture of the foreground becomes black.

You can use the mix shader node to balance any other shader and a transparent shader.
If you have an alpha channel, just plug it in the mix shader fac input.
If you don't, use color informations to drive the fac (Black means 0.0 > top input. White means 1.0 > bottom input, it works with colors value as well).
If rendered in Eevee, you have to change the material setting blend mode from opaque to alpha blend.
Set the Color Management to Standard, look None, to get exact colors of the texture.
In my example a Color Ramp node is used to refine the transition between emission and transparency.

Thank you this is exactly what I needed! I’m so glad for your help I’ve been stuck with this problem for so long! You are a life saver!


text:
Modifying single-object Python script to execute on all selected objects
I have a Python script that I am currently using to (excuse the confusing description) rename a given object's material's image-datablock-names to their actual filenames.
It works correctly, for a single selected object. When selecting multiple objects it only executes on the first object.
Is there a way I can modify this script to execute/iterate through each/every/all selected objects?
import bpy
import os

# Set the material_index to 0 ( the first material )
bpy.context.object.active_material_index = 0
# Go through list of materials assigned to selected object

for material in bpy.context.object.data.materials:
    material_index = bpy.context.object.active_material_index
    old_name = material.name
    try:
        # Get its first material slot
        material = bpy.context.active_object.material_slots[material_index].material
        # Get the nodes in the node tree
        nodes = material.node_tree.nodes
        # Get a principled node
        principled = next(n for n in nodes if n.type == 'BSDF_PRINCIPLED')
        # Get the slot for 'base color'
        base_color = principled.inputs['Base Color'] #Or principled.inputs[0]
        # Get the link
        link = base_color.links[0]
        link_node = link.from_node
        # Rename texture to image name
        link_node.image.name = os.path.split( link_node.image.filepath )[1]
        # Rename the material to the image name excluding the extension
        textName = os.path.split( link_node.image.filepath )[1]
        textName = os.path.splitext( textName )[0]
        # Print the results
        print( "Material Old Name:", old_name, )
        print( "Material New Name:", material.name )
        print( )
    except:
        print( 'not found' )
    # Add 1 to the material_index count ( move to the next material )
    bpy.context.object.active_material_index +=1

My meager misunderstood attempts at wrapping the entire script:
for obj in bpy.context.selected_objects:
    #pre-existing script, etc

perhaps obviously failed.
Thank you very much for any help, in advance.

Here's a suggestion using Pathlib and bpy.types.Object.material_slots.
Using bare try: except doesn't let you debug your code in case something goes wrong. You can either catch the right exception at every step or test if your variables contain the correct data beforehand. Ask for forgiveness vs Ask for permission.
import bpy
from pathlib import Path

def rename_materials_and_image_textures(obj):
    for material_slot in obj.material_slots:
        material = material_slot.material
        if material is None:
            continue
        principled = next((n for n in material.node_tree.nodes if n.type == 'BSDF_PRINCIPLED'), None)
        if principled is None:
            continue
        base_color_input = principled.inputs['Base Color']
        if not base_color_input.links:
            continue
        link = base_color_input.links[0]
        image_node = link.from_node
        if not hasattr(image_node, "image"):
            continue
        image_filepath = image_node.image.filepath
        if not image_filepath:
            continue
        image_stem = Path(image_filepath).stem
        image_node.image.name = image_stem
        material.name = image_stem

for obj in bpy.context.selected_objects:
    rename_materials_and_image_textures(obj)

You could use a cache system to avoid processing materials multiple times since one material can appear in multiple slots in one object, and it can also appear in multiple objects' material slots. Hopefully the script doesn't take too much time to compute so it shouldn't be a concern.

This works very well. Thank you very much for the help and information. I noticed you added back in the material renaming which I guess I had only removed part of in my initial example (didn't need for my use-case), but is simple to activate and deactivate as needed and could definitely come in handy.

import bpy

def func(obj):
    # Set the material_index to 0 ( the first material )
    obj.active_material_index = 0
    # Go through list of materials assigned to selected object

    for material in obj.data.materials:
        material_index = obj.active_material_index
        old_name = material.name
        try:
            # Get its first material slot
            material = obj.material_slots[material_index].material
            # Get the nodes in the node tree
            nodes = material.node_tree.nodes
            # Get a principled node
            principled = next(n for n in nodes if n.type == 'BSDF_PRINCIPLED')
            # Get the slot for 'base color'
            base_color = principled.inputs['Base Color'] #Or principled.inputs[0]
            # Get the link
            link = base_color.links[0]
            link_node = link.from_node
            # Rename texture to image name
            link_node.image.name = os.path.split( link_node.image.filepath )[1]
            # Rename the material to the image name excluding the extension
            textName = os.path.split( link_node.image.filepath )[1]
            textName = os.path.splitext( textName )[0]
            # Print the results
            print( "Material Old Name:", old_name, )
            print( "Material New Name:", material.name )
            print( )
        except:
            print( 'not found' )
        # Add 1 to the material_index count ( move to the next material )
        obj.active_material_index +=1

for obj in bpy.context.selected_objects:
    func(obj)

You can directly iterate on material slots without having to change the material index, for mat_slot in obj.material_slots: material = mat_slot.material. see https://docs.blender.org/api/current/bpy.types.Object.html#bpy.types.Object.material_slots also bare try:  except are not a good idea, they will suppress any error in the block of code which is quite long, so it will be harder to debug. Also, this doesn't seem to rename the material ?

This, at least just directly copy/pasting in to my Blender 3x project, does not seem to function correctly. Could be an error on my part, though. Thank you very much for your reply and help, regardless.


text:
How do i remesh a Circle?
I am trying to find a good solution for remeshing a circular faces...
Is there something obvious i am missing ? I want the circle to be made out of quads, like if you would subdivide a plane...
thanks in advance

Hello, could you please show your current mesh?

you can use grid fill, to get a circle mesh filled with quads:

here is how you make a circle in a grid and then you can delete the inner vertices and do grid fill:

for this you need to enable the LoopTools add-on (which is delivered with Blender)

thanks, super helpfull

you are welcome!


text:
Text Cursor animation using Geometry Nodes
I want to make an animation of a text cursor going back and forth.

Right now, I'm using a plane and animating it's position using keyframes, which is imprecise and annoying.
I have tried inserting a pipe | character in the middle of the text, but that pushes the text forwards/backwards which is not what I'm looking for.

Is there a way to animate a text cursor in a way shown above (using a position value), but so text doesn't get pushed forwards/backwards?

Maybe this can help...
I'm using a mesh island node to individually select each of the characters, and then using a bounding box node to find where the cursor should be relative to that character. I'm then setting my cursor x position to match, with some extra scene time nodes to make it blink :)

It works great, but unfortunately it skips spaces...


text:
How can I get the evaluated transform of a simulated rigid body without baking to keyframes?
I'm trying to get the current evaluated transform from a simulated rigid body.
I have tried to use the evaluated depsgraph but that doesn't seems to work like expected:
obj = bpy.context.object
dg = bpy.context.evaluated_depsgraph_get()
dg.update()
eval = obj.evaluated_get(dg)
eval.matrix_world
obj.matrix_world

This returns the same thing for both the non evaluated and the evaluated object.
>>> obj = bpy.context.object
>>> dg = bpy.context.evaluated_depsgraph_get()
>>> dg.update()
>>> eval = obj.evaluated_get(dg)
>>> eval.matrix_world
Matrix(((0.7632400989532471, -0.6457931399345398, 0.020389333367347717, 2.950727939605713),
        (0.6242920756340027, 0.728961706161499, -0.2808455526828766, -4.03101921081543),
        (0.1665050983428955, 0.22708149254322052, 0.9595363736152649, 4.02522611618042),
        (0.0, 0.0, 0.0, 1.0)))

>>> obj.matrix_world
Matrix(((0.7632400989532471, -0.6457931399345398, 0.020389333367347717, 2.950727939605713),
        (0.6242920756340027, 0.728961706161499, -0.2808455526828766, -4.03101921081543),
        (0.1665050983428955, 0.22708149254322052, 0.9595363736152649, 4.02522611618042),
        (0.0, 0.0, 0.0, 1.0)))

How could I solve this?


text:
Stop a long running operator with escape?
Would it be possible to write an operator that would allow the user to interrupt it with the escape key or even when a value gets changed in the redo pannel? Any pointer about how to do this?

This can be done with modal operator (you can find example here, look for 'Modal Execution'). I'm not sure about redo panel but executing some function on Redo can be done with handlers bpy.app.handlers.redo_pre or bpy.app.handlers.redo_post. Just append your cancelling function to them, like this:
import bpy

def my_func(self, context): # must have 2 arguments (3 if called from class)
    print('Got Redo!')

bpy.app.handlers.redo_pre.append(my_func)

It will be executed on each redo. Use bpy.app.handlers.redo_pre.remove(my_func) to remove redo handler or bpy.app.handlers.redo_pre.clear() to clear all redo handlers

Thank you for the answer! Are there not a way to check if a key is down or something. Making it Modal is just a bit too overkill maybe?

I don't think there is another option because the idea of the modal operator seems to be exactly in serving as a listener to the user commands (keyboard, mouse, etc). It can run in the background, you just need to return {'PASS_THROUGH'}  in the modal() method instead of {'RUNNING_MODAL'}. In this way, as I know, it doesn't freeze other operators and waits until some event which you defined in the modal() method happens. Or I guess it can also check some value. By the way, the full list of events references you can find here.


text:
Moving multiple faces at once
I am having trouble trying to move multiple faces at once in different directions.
I can't move all the faces selected without altering the other parts of the model, even though I have already hidden those parts. I also don't know how to move every individual face in particular different directions (in this case, to the center).
Can anyone help me? Thank you.

I am not sure about Move but you can Extrude all faces from the center using the Extrude Individual on the Tool menu when in Edit mode. Center is calculated based on which Faces you select not the Origin Point.

Sorry, I meant "extrude". How do I use this tool?

Enter Edit mode, Select the Faces you want to extrude, in the Tool panel (on the left) there is a button "Extrude Individual" click on that and use your mouse to set the Extrude distance.

That worked. Thanks. I have another problem now, can you help?

I want to select the faces in a specific pattern, having an unselected face after a selected and vice-versa.

It is best to ask a new question. But I do know the answer to this one. In Edit mode, with all faces selected, on the Select menu chose Checker Deselect. I created a script that does a very similar job before I found that command. http://www.jumpstation.co.uk/flog/Oct2017.html#p141020171620

Okay. Thank you for helping.


text:
How do I replicate this series of numbers in my practice project
so I followed this tutorial to make a digital clock and I hit a snag around time 4:07 when I wanted to replicate the numbers displayed in this first screenshot.
I tried to use the 'join strings' node and a bunch of other things but it did not work. I have attached the screenshot to this post. Here's the link to the blend file.

The "string to curves" node should be outside of the "Timer" group:

Something like this:

If, from this group, you output a geometry for each time part, you can't join them as "string" after that.

Thank you @lemon!!! So sorry I didn't respond earlier : (. I gave up on the project, lol. But I know I shouldn't have that attitude though, just moved on to another one, but I tried it and it worked! Thanks for helping a noob like me!