text:
A quick way to convert 3D models into 2D
I'm trying to convert the 3D model of a humanoid mesh a 2D flat model,because I've thought : since I want to do the projection painting of an hand drawn image that's 2D,that you can see below :

if I want to get the best result I should use a 2D mesh. I have found this thread :
Convert a 3d model into a simple 2d model
and I have used that tecnique to make the conversion. Below you can see what's the result. The rendered image is good,but the exported svg file is not good. The worst problem of this tecnique is that the mesh is without textures ; there are a lot of doubles ; the body is not splitted into single parts...do you know if there is another tecnique or a combination of modifiers that gives a better result ?
This is the rendered 2D image :

This is the exported svg file :

check the following question How to export fills on Freestyle SVG export?


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Changing IOR for Subsurface Scattering in Cycles

I am using subsurface scattering node in cycles and want to change IOR of mesh (human muscle). But there is no option to do so. IOR option comes with Glass BSDF node but it changes my mesh appearance. Is there anyone how to to that?
Does anyone know physical background (formulas, or law) behind subsurface scattering node in cycles. How much light will penetrate, etc? I checked in blender wiki but it is not stated there.
Thanks

Refraction is when light get bent while traveling through an object. Subsurface scatering is when light enters the mesh and gets scattered inside. It does not "pass through" so to speak. there for their is no IOR(index of refreaction). Besides, refraction on a human muscle would just look plain weird...

Well, I'm really happy that you asked this question.  I decide to try using the Fresnel Input Node to modulate the various Input sockets of the SSS shader and the results are interesting.  Using Fresnel for the radius adds depth, but it does dampen the SSS effect for the front facing poly's, so maybe it would be better to mix this setup with a stock SSS node.  Using 3 Fresnel Nodes with different IOR values and a Combine node for the Radius not only adds depth but adds a tone gradient which makes the SSS results interesting I think.
Here is a basic setup which uses a model that I recently rebuilt for someone so it can be used with Cycles bake.
There is an Environment Texture set to a value of 3 and a front facing overhead sun light at about 11:00.
The model on the Left uses a stock SSS shader with radius values of 0.9, 1.5, 0.7. for the hair.  The values are 2.0, 1.45, 0.35 for the face.
The model in the center uses a Fresnel node plugged directly into the Radius of an SSS node so all 3 values have the same input.
The model on the right uses 3 separate Fresnel nodes to control the 3 values of Radius for the SSS node.  The Fresnel values are the same as the radius values for the model on the left.
It's subtle and mostly just visible at the edges the way I did it here, but if you put some effort into it you may get somewhere with this.

For materials like skin you don't use index of refraction but you use index of reflection. You can achieve this by mixing your sss node with a glossy shader and change the amount of 'glossyness' as you like. Then you plug a color mix into the roughness value of the glossy node. Then you plug in a fresnel node with the IOR value you want into the factor. Then if you change the value of your two colors you are able to control the amount of specularity based on the angle of the light.
Hope this is what you are looking for!
-Bert

source: Stack Exchange

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

sort: votes


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Texture painting on the alpha channel (2.73)
How do I paint on an RGBA texture's alpha channel in Blender 2.73?
I'm not actually using it for transparency, so I would prefer to visualize the alpha channel as a grayscale image while painting, if that's possible.

The paint modes named Add Alpha and Erase Alpha may be what you are looking for.

If you are using a pen tablet then you can use the pen eraser to use Erase Alpha without having to change the blend mode in the UI.  There does not yet seem to be an alt key press that allows the pen eraser to toggle between Erase and Add.
Personally, I think the better way, for now, is to paint the texture the usual way and then use GIMP to add this texture to the Alpha channel of some other texture.  Blender does not really seem streamlined yet for working with and packing multiple images together in a convenient way. Maybe I'm just missing something and it's all there nicely workable already, blender can do lots of things that are not well documented :)
If you follow this link, I show how to add an image to the alpha channel of another image using GIMP.  Dotted line on curve?

Yeah, I might end up doing it outside of Blender, but I'll try Add/Erase Alpha for now. Followup question: is there a way to change the color to something other than white when alpha is 0? (Black would be more natural, at least for what I'm doing.)

I don't use this ability so I'm only mostly guessing but I think the 'white' is the Viewport Material color.  The Black is the default texture color.  If you look in the left window shown above, you can see that there is no white.  It's transparent.  You could put another texture on the lower slot that can be any color you want.

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


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Blender Material Color in Mitsuba (or any other) Shader
I have imported a large WRL file (contains >3000 parts) with colors included (one material for each part!).
In Cycles and Blender-Render, the colors are rendered just fine.
But what do I do if I want Mitsuba, Luxrender or Yafaray as renderer?
Is there a way to get the Blender-material-color and put that in a 3rd-party material?
I know how to make a material with python and apply it to a mesh. But how do I get the color of the selected object's blender-material?
How to make a Mitsuba, Luxrender or Yafaray matrial is one thing I yet have to find out too.
Thanks for your help.

Luxrender and Yafaray provide addons for blender which allow the creation of their respective materials from Blender's GUI.

Like the "Convert to" button? Yes, unfortunately this does not work :-\

More like an interface specifically designed for creating a material for whichever render engine

For BI you can get the diffuse color with bpy.data.materials["Material Name"].diffuse_color. Cycles is trickier due to its node-based nature.

Right! But I've imported a WRL with the correct color from CAD. It creates a Blender material with the color from CAD. Now I need ot get this color with python. How can I do that?

Ok! That might help! bpy.data.materials["Material Name"].diffuse_color

You can read the mat color from Blender Internal material like so:
# from material
mat = bpy.data.materials['Material_Name']
color = mat.diffuse_color

# or from object
ob = bpy.context.active_object
if len(ob.data.materials):
    # get 1st material slots material
    mat = ob.data.materials[0]
else:
    # no slots
    print("No Material")
    mat = None
if mat:
    color = mat.diffuse_color

To change LuxRenders material diffuse color:
mat.luxrender_material.luxrender_mat_matte.Kd_color = color

Mitsuba:
mat.mitsuba_material.mitsuba_bsdf_diffuse.reflectance_color = color

In Yafaray there is no need to change anything, it will use:
mat.diffuse_color

Here we go!
After a few tries it works!
import bpy

if bpy.context.selected_objects != []:
    for ob in bpy.context.selected_objects:
        if ob.type == 'MESH':
            objcolor = ob.active_material.diffuse_color
            ob.active_material.mitsuba_material.mitsuba_bsdf_diffuse.reflectance_color = objcolor
            ob.active_material.luxrender_material.luxrender_mat_matte.Kd_color = objcolor

This is it! Select all objects and run this script. The diffuse color will be added to Mitsuba and Luxrenderer.

Nice usage of active_material! If my answer helped and you figured it out pls mark it as correct;)


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fluid leaking through obstacles
I'm a beginner to blender, so please ignore my mistakes and be kind enough to guide me through this :)
I've scene this question before, but never got a satisfactory answer. I'm working on two animations, a over shot water wheel, and an Archimedes screw.
 My problem is, the fluid simulation does not work the way I want it to be.    when I bake it with the fluid it starts leaking through the solid object, even though i made it an obstacle . I tried baking it with a higher resolution and thicker walls, but i could not get the expected results.
Is there any way to stop this ? please help me to solve this

It is usually about resolution, try adding a subsurf modifier before the fluid and/or increasing the res in the domain fluid settings.

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


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Domain stays a cube when baking?
Whenever I bake my domain, it stays a cube. It does work when the fluid object is outside of a hollow obstacle I've placed it in.

I've recalculated the normals, and tried resizing the domain, but nothing really seems to work. Blend file is below.

Recalculate the normals on all the meshes. Remember to go to edit mode and select all faces. Then go to Your fluid settings on the glass and choose "volume" instead of "both" under volumen initialization:
I have added the fixed file below:-)

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


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Wind Force Field not working in my scene
I have tried everything in my scenes but the wind force field is not working can anyone help for my this file flag animation

Wind must be a large value

Welcome to bse.  Please elaborate a little on what you have tried, (chances are it's not everything), what references you are using, what result you are after.


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Blender 2.79 and 2.78c crash on startup with Exception access violation error
I've been trying to install blender 2.79 on my windows 10 machine but it crashes on start up and shows the error bellow :

I tried changing the sound properties but it did not work, I updated my graphics card drivers, I tried installing a previous version of blender (2.78c) but I kept getting the same error, I tried installing the 32 bit and 64 bit version but the problem persists, I uninstalled every instance of python i have installed, deactivated my firewall... I even tried debugging it and i got this

I also tried the --factory-startup option but i got the same results as the debug case so i tried using the  latest build version with --factory-startup

This is trully frustrating and I really need it for work so any help would be much appreciated.

Have you tried running as administrator?

Yes, it still crashes

What have you tried so far apart from what you wrote? There are a lot google results that will tell you exactly what we will

I tried updating my graphics card drivers and i logged out of my microsoft account, both of these also didn't work

Try --factory-startup

Where are you downloading blender from? Is the version in last screenshot same as in prior?  Can you post result of factory startup and debug together.

Sometimes I've seen that error when Windows defender has decided that the program in question is 'dangerous'. If you have Defender enabled, you can open WIndows Defender Security Center, select App & Browser control, and look at the setting for check apps and files.  If it's set to block, defender may have blocked blender without telling you. This URL has an explanation on how to unblock: https://answers.microsoft.com/en-us/windows/forum/windows_vista-security/how-do-you-add-a-program-to-allowed-items-in/7f5c2ded-394a-40f4-bbe7-762fdd716a2f

sorry, the URL I posted was wrong and it's too late to edit my comment.


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Normals acting weird

I've been modeling these buttons, and the middle one keeps having this weird shading, like there was something wrong with its normals.

I've checked them and they seem to be ok, but the shading problem persists, unless I purposefully flip the normals of the faces framing the 3 buttons.

Once they face in the wrong direction, the shading issue goes away, but the flipped polygons would cause problems down the road, so I really want to fix them.
I've tried smoothing, recalculating, and setting them from the faces, to no avail. I have no modifiers or anything on the mesh.
Does anyone have any idea what's at play here? Many thanks!

You need to Clear Custom Split Normals Data, hard to guess how you messed up the split normals though:


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GN: Controlling the Rotation of an Extrusion and aligning its Normal to Normal/Tangent/etc. of a Target?
Dear Blender Community,
Working on following Idea, I had a few problems:
The original Idea:
So I was trying to create an Extrusion Plus Nodegroup, where I can easily control the Extrusion Length, the Rotation (really the Rotation Offset from the original Normal) and the Scale.
Also this Nodegroup should be compatible with Repeat Zones.
Right now it only works with extruding single faces, since I haven’t figured out how to separate the calculations for every Mesh Island. If someone could give me a hint that would be great!
To control the Rotation from the Extrusion Center, I set the position to Origin and afterwards back to the original Position, if there is a more elegant solution to this I would be glad to learn.
Here is my cureent Node Setup:

The advanced Idea:
It would be great to be able to find the nearest point of a target geometry (i.e. a curve) from the extrusion, snap to that position, read the tangent of the point and align the extrusion normal to the tangent.
Resetting the Extrusion to an arbitrary Position other than the Original one should be easy, but aligning the Rotation seems like I bit off more than I can chew.
First I would need to reset the Extrusion so its Normal faces Z, which I can’t make work.
Would I need to sample the Target’s Tangent AND Normal?
If you have any Ideas regarding one of these problems or can point me to ressources for me to further learn I would be very grateful.
I am still on the low intermediate side of expertise regarding Geometry Nodes, because my Math skills and Computer Logic Knowledge are bad.
Thanks in advance! Best wishes,
todesdigga

i think adding some images with annotations to show us how it should look like would help a lot!

@Chris Oh sorry I totally forgot to add the Screenshots, hope it makes more sense now :)

btw you know you could use the center input of the rotation node. (it's the "more elegant" solution)

Thanks shmuel, I did not get that to work, neither for single face extrusions nor multiple faces. I thought the process would be:
Position > Vector Rotate > Set Position (with Top Selection), and for the Center also the Position but with an Evaluate on Domain set to Face. It wasn't.
Do I need to set a Group ID per Face? And how would I feed that into Set Position?

The reason I stopped trying to make the Vector Rotate Node work with anything other than zero at the Center Input was Markus von Broady's answer here:
https://blender.stackexchange.com/questions/278367/what-is-the-center-in-vector-rotate-node
It seemed the best option is to first Center my Extrusion at 0,0,0 and reapplying the original Position after rotating, since I did not really get the Implications of Robin Bett's explanation...

This answer also did not work for me:
https://blender.stackexchange.com/questions/268570/rotate-each-face-on-their-own-axis-in-geometry-nodes
Set position with Top selected and Position evaluated on Face Domain for Center of the Vector Rotate still gives me a weird Pivot Point which is not the Center of the extruded Face. Is the problem that the Vertices of the extruded Face are also connected to the rest of the mesh? I understand that everything gets more complicated if its several Faces being extruded, but with just one face?? Rotating an extrusion around itself seems like a common idea?


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Triangulated Edge Subdiv for Differential Growth in Geometry Nodes - Improvements?
I tried to create a Geometry Nodes Tool similar to this destructive Add-on https://github.com/inca/blender-differential-growth
This is related to my question here:
Capture Top and Side Boolean from former Extrusion to new Geometry (Geometry Nodes)
I succeeded in getting the mesh to sometimes triangulate and thus providing more Geometry to work with (like in the Add-On), but it is doing it for everything at that iteration and not where it is actually needed most, trying to separate the mesh and only triangulating the parts that need it and rejoining with the untriangulated did not work well.
In the .blend-File below I tried to create some guide-curves with a Differential Growth Pattern and thought I could extrude my Mesh with a second Repeat Zone to always snap to these Curves, but it gets confused pretty quickly and messes up.
I don't know if this way of edge subdivision is news but I was pretty happy to have made it work (with the help of @lemon, thank you!) so I thought I would share it here.
I have cleaner Versions of this but some Alpha-Version of Blender messed them up, so I will share them if they work again.
My Question here about Self Collisions is also related to this tool:
Mesh Self Collision in Geometry Nodes?
If you have suggestions to improve this, maybe without need for Curves, I would be glad!
Best wishes, Todesdigga


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Blender rendering blank videos
I am seeing a strange behavior with Blender. Let me explain the detailed workflow of what I do.

I use OBS studio to record my screen and audio. The output is
produced in mp4 file.
I edit the video in blender.
Final step render the video to produce the final output.

The steps are pretty easy. Everything was working till now and suddenly I am seeing blender is rendering blank video with audio (Preview works just fine). There is no picture at all, its just dark black video. I tried few options and here is the observation

It is happening with videos recorded recently (there was no change in the obs configuration though)
If I render the raw video in after effects/handbrake etc and use that file in blender to render the video again, it still doesn't work.
Old videos are rendering without any problems.

I am totally clueless and not sure what to do. Tried uninstalling and reinstalling blender but that didn't help either. Here are my settings for blender

Update: The problem was occurring due to change in Output Quality setting. I changed it from "Lossless" > "Perceptually lossless".

I realized late night that there is one difference in the Project settings - Output quality. In earlier projects, it was set to Perpetual lossless. I will try to change the setting and re-render again.

Maybe you can provide a blend file with nothing important on it, so we can experiment and try to find a solution more quickly to help you? Maybe it is a project settings you mislooked. You can upload blend files here and link to this question like an image: https://blend-exchange.giantcowfilms.com/

I realized that the problem was happening due to Output quality setting. I change it from "Lossless" > "Perceptually lossless" and it worked.


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Blender 2.8 crashes while compiling scene
enter link description hereI have a new Mac Book Pro - with 32 gig of ram plenty of disk space.  Every time I try to render a scene using cycles I get through 5-30 frames and blender crashes.  Any thoughts or help would be really appreciated.

Share your blend file

I added a link above.  This blend file is about as simple as they come but the render still crashes.  I never had this problem in 2.79.  i9 processor 32 gig of ram.  I have reduced as many settings as I can think of but the scene always stops along the way.

@RSchuler the blend link you shared is not publicly accessible.

This sort of situation is why it is often recommended that you render to an image sequence rather than to a video file. Once all frames have been rendered you can quickly convert the image sequence into a video format.
If blender crashes after 20 frames, then render 15 frames at a time. You could also use a script that will repeatedly start blender and render one (or 10) frame each time.
In the output panel you can enable placeholders and disable overwrite to get blender to only render frames that haven't been rendered yet, note that crashing in the middle of a render will leave the placeholder. This should allow it to continue rendering from where it was when it crashed.
When you have a blend file that causes blender to crash, consider submitting a bug report so that the developers can find why and find a fix for the next release.

Just for the sake of clarity.  The output is rendered to an image sequence all out is PNG files.


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Struggling with making an audience/public for an gladiator arena
I am a blender newbie, slowly catching up with the program and geting into 3D modeling. I've managed to create a huge arena model, and I have a lot of audience seats that should eventually be filled with people... I just can't think of how could I fill the entire arena with people, without making it way to big of a performance struggle... Does anyone have any idea how that is usually done? Like just a guideline in which direction should I head with it?
EDIT: I want to use the scene for gaming purposes (fighters inside of the arena) in Unreal Engine 4. Since it is a top-down level in UE4, I will need the crowd in the audience. Also I need to show the entire arena with crowd for the intro animation in the level. So am wondering how to simulate, let's say 5000 people in a crowd, cheering ? (like they do in the Football games, for instance)

Thank you for your help!

Check out the Crowd Master add-on. http://crowdmaster.org/

Could you better describe your siutuation? Why in your opinion are you struggling with performance? Are you referring to the modeling in the 3D viewport or render times? What's the purpose of thes scene? Are you using this in a game engine or a shot? Does it requires to handle several LODs because you need close up of the crowd or it's always in the background?

I edited the post to answer your sub-questions. I was wondering if having 2000+ low poly people in a stadium, cheering in a simple animation, would be too much for a level performance-wise


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Cant export as .fbx file? Whats going on in here?
I am trying to export my project as .fbx file so I can use it in UE4, but when i try to do it, I get this error in the picture below... What am i doing wrong? The project consists of multiple objects, there are no textures rn animations in it, just meshes.
TY!

export settings:

Hi, it's really difficult to say, I could just spot a repeating "int32" problem there... it could be some kind of conversion of overflow error, maybe, but your scene seems quite complex, and you didn't show/describe it, or your export settings... try if you can export a basic cube, so to be sure the exporter works, then try a copy of your file, and export only one object at a time, so to spot if the issue is specific for one of them, and report what found....

Instead of an image, can copy error message from system console.  Error is a keyerror,  eg when looking up a dictionary dict[key]  their is no value for key. The incorrect key is (nan, nan)  (not a number) returned from _uv_tuples_gen(...) and used to access some lookup table uv2indx[key].  Suggest using the "Report a Bug" button of the fbx import addons preferences.

Hi, ty for your answers. I have tested the exporter on a normal cube and the exporter works just fine. I've managed to export the project as .obj with no problems (its just that in UE4 it imports it as one big mash, not separate objects, and as a very very tiny object). Edited the post with export settings.


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UV unwrapping how to seperate seams
How do I separate them like romeo and juliet

I have selected the middle with alt and marked seam, but they don't seem separated?

so you must not have separated the two parts

So i select again and unwrap?

perhaps share your file to see what went wrong: https://blend-exchange.giantcowfilms.com/

I found the reason, somehow I pressed O and it can be separated, proportional editing?

Actually the problem was that you had activated the Proportional Editing mode (which allows you to select the closest vertices), just deactivate it.


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Rendering "Hand-drawn" Curves on Surfaces
As a mathematician (a topologist), I'm constantly creating diagrams similar to those shown below.

My broad goal is to make these diagrams look more professional by drawing (modeling?) them in Blender and then rendering them via NPR techniques.  The qualities that I'm looking for are:

The drawing is rendered with a "toon" or "hand-drawn" feel.
The pictures look "polished" and "crisp"

Examples of what I have in mind are renders which look like:

My problem is this: when I snap a bezier curve to the vertices of the mesh, the rendering does one of the following:

The curve "comes in and out" of the surface (i.e. the curve is puncturing the surface).
The curve is displaced from the surface and isn't flush.

My question is this: how do I draw an arbitrary smooth curve which is flush on a surface?

This question sounds too broad as it stands. What part of the workflow are you having difficulties with, modeling those shapes, drawing the lines, rendering NPR images? Do you already have the shapes you wist to draw over? Could you rephrase your question to focus on what part you are stuck?

You most certainly can do what you want with Blender, but I have to agree with @DuarteFarrajotaRamos.. so here's a Blend File  that shows a one of many possible approaches. It might get you started,  and  trigger some more specific questions.


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Curve has no vertices when converted to a mesh
I'm trying to make a curved plane using a bezier object, however when I do ALT+C and press "Mesh from curve/meta/surf/text" and go into edit mode, there are no vertices on the object.
Bezier curve in edit mode before converting it

Curve in edit mode after converting it (no vertices)

Any reasons as to why this is happening? (It worked fine on another curve I was working on when I first started the project)

If the 2nd pic is in Edit mode, it appears the object is just a line not a plane as such.  Also it's edges are all highlited which can confuse the view somewhat.  Press A to clear the selection and then CTL-TAB --> Vertices to see the points it should have.

Thanks so much! I guess I was in edge select mode instead of vertex


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Loop cut is skipping one face in particular
The loop cut is skipping one face in particular (the circled one) and then continuing to the other side. I tried removing doubles and that didn't work. I tried selecting the n-gons and that didn't work. I also tried dissolving the edges and sliding them around but those didn't solve it either. Any suggestions? It looks like there's something blocking it or there's a kink in the mesh but I don't know how it got there. I've been working on the top of the anvil for some time and then I go to the bottom to find this. (And yes, I've checked similar questions but the answers did not help me. All of the solutions were things I've already tried).
Here's the file:

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

you already asked the question, there can be several reasons: your face is a ngon, there's a inner face, you have to remove doubles...

I've added the file

Please do not re-ask a question just because you did not like the response to your first question. You can always edit your posts to add more information.

Lol how about no? And besides I already did that and it didn't work. And the answer I did get I didn't mind

The problem is being caused by the parallel set of vertices (circled in red). This is causing a break in the set of faces on which you wish to create loop cut.

When zoomed in, it looks like this

So the solution is to dissolve one set of parallel edges, that is not connected to the edge marked in green.(hot Key 'X')

Once they are dissolved, you will be able to loop cut through those faces.
Checkout the attached blend file in which I dissolved those edges.


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I can't see color in Material tab
I used to use blender a long time ago and now I started to use it again but I can't find the color option in the material. Is there anyone that knows how to fix it please? really appreciate it.

 I know that I can change the color where it says "Diffuse" but when I do that and want to add shader in the "Node editor" it doesn't show any output or input, so don't know how to do it.It would be greatly appreciated if someone can help me with this.

are you in Cycles Render?

Please add a screenshot of the entire blender window, showing where you expected the missing color options to be.

No I am not in cycle render.

It doesn't let me add any screenshot!

An easy way to add a screenshot (if you're in Windows 7 or Windows 10 at least) is to press Win-key and type Snipping Tool and press enter. With that create a new snip, go to edit your post here, press Ctrl+G (insert image) and then just press Ctrl+V, which will paste the snipped image to the post.

Thank you so much mate! I just edit the post and explained more about what I meant.

It would be easier to understand the question if you add a screenshot / reference image of the option or a video from e.g. Youtube with mentioned functionality you're searching for (from e.g. another site or alike) at  as I don't understand what Color option do you want to find, whether you want to use Cycles render or not etc. So far you still use Blender Internal engine as shown in the answer

1.
It might be that your panels are arranged in a non-default way.
If you use Blender Render or Blender Internal renderer (which is the default in a newly installed Blender):

Find the Diffuse panel and change the color there

If you use Cycles renderer:

Find the Surface panel and change the color there

2.
It also might be that you have created the material in Blender Render and then switched to Cycles renderer, or vice versa - which makes the material color slot disappear since the Blender Render and Cycles materials are not compatible (unless you know your way in complicated node setups).
In this case, easy way is to just remove the incompatible material from the minus button and add a new material by clicking 'New'.

I hope this helps :)
If not, post a screenshot of your material panels to the first post, that would be helpful.

But this way when I got to Node Mode to add more stuff to my material, there is no shader (any small boxes) shown to be able to add or edit anything.

It's hard to figure out what you're experiencing if we can't see screenshots of what's happening. I really recommend some kind of tutorial video about shaders and nodes for learning some good working methods with them. Like this one (scroll a little bit down for the video): https://cgcookie.com/articles/pbr-in-blenders-viewport


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Blender 2.91.2: Rendering looks pixelated in Blender's image view (rendering is not pixelated!)
The rendered image, in Blender, looks very pixelated.
But, when I save the image and open it paint.net, the image is as clear as it gets.
You can see that in the following images. Best image is the third one. All images are at the same zoom level as in Blender (1:1).
Any ideas, hints and "duh"s are appreciated.
This is in Blender:

Same image stored and opened in paint.net:

Side by side:

Left image, sharp as it gets viewed in paint.net. Right: Pixelated image in Blender image view.

After a day, the problem went away. Maybe a reboot was required?! Anyways, the problem is gone and I don't know what it was.


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Difficulties centering the object on the middle of the screen
I have some difficulties centering the object on the middle of the screen. Infact when I press the mouse wheel the view seems to fly away too fast. This is what happens : on the picture below you see that the object is too far,I don't see it clearly and I can't edit it :

instead,below you can see that happens when I scroll a little the mouse wheel : the object "disappear" totally.

I have also attached this video to explain better. thanks.

seems you are running into a viewport clipping issue. Have a look at this answer https://blender.stackexchange.com/questions/8553/why-does-part-of-my-model-disappear-when-i-zoom-in-on-it-in-the-3d-viewport

hello man. I tried to play with the start and end clipping values but I haven't been able to fix the problem.

From the dimensions I see that the object is quite large 2000 the the y dimension and the clipping distance of of the viewport in your attached image is 1000 try setting it to 5000 and the near clipping distance to 0,0001

I have solved your problem by Centering the thing I want to look at in every angle. Go to top view [numbpad 7], drag things I want to look at to the centre of my view by holding [shift] and [mouse 3]. Do the same with view from the front and from the right/left. When that's done you should be able to interact with your thing perfetly.
Another way to zoom in slowly is by holding [ctrl] nad dragging with [mouse3].
Yet another way to wiew you object is by using [shift]+[f] shortcut. This shortcut lets you use your WASD keys and mouse as if you were playing a videogame. With [Q] and [E] you can move up and down.


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How to move more objects in a coordinated manner with the particle system
Hello to every blender user.
I'm trying to configure the particle system because I want that it generates a certain number of cars that should follow a curve. I have different types of cars. Here's how I built the cars. Each car has 4 wheels that run continuously. I put the car's origin in the center of the car body and I have parented an empty object to it. Then I also parented the 4 wheels with the empty object.

Finally, to make the wheels spin I created a driver, configured as follows:

type = scripted expression
expr = -var
object = Empty_car_citrus
type = x location
space = world space

I come to the point. I want to configure the particle system so that it can make the car body and the 4 wheels walk together (not disorderly). And I do not know how to do it. On the particle system configuration, I can choose between object and group. I tried to give to it the the car body as an object and the car is moved correctly. Also a single wheel moves correctly. But I do not know how to do if I want to move the car body and the 4 wheels together, at the same time. I also tried to add the wheels and the body inside a group and then I gave the group name to the particle system, but it does not work. The parts of the car move messy. This is because the car is not a single object, but is made up of 6 objects. The car body, the 4 wheels and the empty object. It would be easier if I could join the wheels with the car body, but I can not, because then the wheels do not turn anymore...I have also another problem,the cars cross the floor...

Try applying the scale, so they all have a scale of 1.0 - Ctrl-A->Scale. To align the car to the floor, move the object origin to the bottom of the car.

I have applied the scale to each component of the car,like the wheels and at the empty object,but it did not work. Infact I don't know which object should I choose on the render tab of the particles configuration...if I choose the car body,the wheels haven't been attached...


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Improving an Iterative Shrinkwrap Node in Geometry Nodes
Right now I am trying to create an iterative Shrinkwrap Modifier, to achieve two goals:

Displacing the middle of an otherwise plain Grid according to 3D Scanned Forms, to create some VDM Texture (subtracting the plain Grid Position from the displaced one to get displacement info, to later use that on other meshes, related to here:  Using VDM Brushes procedurally in Geometry Nodes? )

Shrinkwrapping the same roundcube around many different 3D Scans to later mix/morph between these forms, as they all have the same Indices.

I understand that there is no one fits all solution and the scanned forms can be very different, but the approach in the blend-File below works ok for some of them.
The biggest problem is that it relies on the Grid/Cube iteratively searching the nearest point while getting closer, and doesn’t want to get in the Nooks and Crannies of the Scans, as there is always a nearer point on the surface than in those deep areas.

The easiest way would be having a „weighted proximity“ (like in find shortest Edge Path), where if most of the Grid already conforms to the Scan, the parts that have a greater Distance from the Grid are favored. But I don’t know if and how its possible to hack something like that.
One approach was to raycast from the (negative) Grid Normals and displace according to the Hit Distance. But in my tests it was very prone to glitches, dealing with false hits, no hits and the transitions between.
Another approach was to change the 3D-Scan from simple/bloated to more complex over iterations, to gradually guide the Mesh to the right places.
Remeshing via Mesh to Volume > Volume to Mesh and blurring the Position, upping the detail every Iteration. I haven’t found a sweet spot yet where the result looks better than my original Shrinkwrap, so maybe this is also a dead end.
Furthermore, it would be neat to have a Relax (?) Function to even out the space of the Grid points after every Iteration. I tried the Relax Mesh Node that @crantisz created here
( Relax vertices in Geometry Nodes ). It seems to somehow work with the Grid, but not with the Cube. Maybe I misunderstood what Relax means, I want the Form to change only minimal, while sliding the points to the places with most stretching. Do you have any tipps how to make that work? Otherwise the Points start to gather at the highest points, which I can only counteract with blurring, at the cost of precision.
I am already quite happy that it works okay and see a lot of creative potential, but if I could fix these issues it would be great and could also serve as a clean Quad Remesh Option.
The .blend-File:
The 3D-Scans in the blend-file are already remeshed low poly and have no textures, to keep the file size small, but it works with detailed meshes too.
The Shrinkcube is the newest version, the Shrinkgrid was from an older file.
The Mix Models Nodegroup morphs between two forms and the Image Textures sampled from their respective original models. Only works when the Iterations for both Objects are the same.

Careful with upping the Iterations as there is a Subdiv Node in the Repeat Zone! The Ping-Pong Node sets after how many Iterations it subdivides.
EDIT: While the first Set Position in the Repeat Zone doesn't break the models in these two cases, in many others it does, it can then just be muted.
3D Models used: https://sketchfab.com/3d-models/reishi-mushroom-ab74ec90a0ed41a99b45d67ebc1ee3d3
https://sketchfab.com/3d-models/japanese-rhinoceros-beetle-larva-b67fb6cbe3fa455c81373aaa9f91fa1a
Thanks to anyone who has some Input or can point me in the right direction,
best wishes,
Todesdigga

I've been working on something like this myself.. starting with a spherified target ..my iteration step: [de-spherify target a bit, source captures closest UV coordinate on target,  de-spherify target more, shrink source pos a bit to new target pos at captured UV coordinate, blur source pos, less with each iteration].. trying to get the source to follow the target to its completely de-spherified state. Looking for a shrinkwrap with undercuts, evenly spread topo. If I get anywhere, will share.. all suggestions welcome.

@RobinBetts Uuuh interesting!
Do I understand you correctly that in the first step you gradually smooth out and "bloat" the Target Object to get closest to the roundcube shape of the Source?
How is that possible? I tried a combination of remeshing, scaling Normals, Blurring and Normalizing Position...
Do you use Raycast or only Sample Nearest?
Can't wrap my head around the UV part. Would love to see it, thanks for your answer!

I go all the way.. normalizing to a sphere.. bring it in gradually, and try to coax the source to follow.. ok but not answer-worthy so far.


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After Extrude > Right Click > Scale, I can't scale only one face
I'm new to Blender and found a problem during a tutorial. When I scale, after Extrude > Right Click, both faces get scaled at the same time. I'm sure there's something that I'm doing wrong I just can't figure out what it is.
After a big online search, this answer  How to scale vertices outwards?
was the only answer that is more related to the problem I have and that offers a valid workaround so, thank you for that.
Though my problem is solved with the workaround and tips I still would like to figure out why is it happening since, as Gordon mentioned, there are a lot of tutorials using this Extrude > right click > Scale method.
I'm sure there are two faces in place since I can see the face and vertices count on the model but when I choose G or S both move at the same time. I've started a new file to see if I was doing something wrong. And on a clean file, it works as expected. The new extrude resulting face gets scaled inwards.
Why is it happening? What am I doing wrong?
Thanks in advance for your help.
Joca

As we aren't sitting in front of your computer looking at your screen and we don't have any idea what tutorial you're watching it's impossible to guess what you've done, You can share your file via https://blend-exchange.com/ following the instructions there and add some images of the problem (https://meta.stackexchange.com/questions/75491/how-to-upload-an-image-to-a-post ) but without those we really can't give you any suggestions.

Hi John. Thank you for your answer and sorry for not uploading the file. Already done.

I think it might be that you have Proportional Editing switched on (with a very low radius, so you can't see the circle that indicates falloff) ?

Robin, that was it! Thank you for your answer and thank you for your time!

@JocaFaria Good to hear it's sorted.  That's why it's usually so important to be able to see Blender's window in a question. We'd have been able to see if proportional edit was turned on immediately from the icon on the top tool bar. For future reference you can take a snapshot of Blender's window via the Window > save Screenshot menu.

Duly noted, @JohnEason. Thank you for your help!


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How do I stop so many .blend1 files from being created
Every time I save my files, it creates a new .blend1 file. I only want one backup. I have the same versions set to 1, but it saves a file every single time for some reason. Thanks for the help.

Well you're renaming the file every time, so it doesn't find a match when it renames the file and a new .blend1 is created rather than the matching file being deleted beforehand.

If you have some form of version control running, the automated backup is completely redundant.

If you want to turn off the backups altogether, Set Save Versions to 0 under Preferences > Save & Load then Save Preferences.

...and having researched further there is a built-in Blender addon with a pie menu for automatic incremental backups!
Search pie in addons and enable Interface: 3D Viewport Pie Menus.

Open the Settings section and scroll down to and check the Save Open Pie: Hotkey 'Ctrl >S' entry. (All the others can be unchecked if you wish.)

When you use ⎈ Ctrl S to save you will now get a pie menu which will look like this if you've not saved the file before:

The Incremental Save >(unsaved) entry (1) is disabled and using Save (2) will bring up the normal file dialog. Save as (e.g:) test.blend.
If you now ⎈ Ctrl S again,
you can click on Incremental backup and your file will be saved automatically with the filename incremented as 'test_00x.blend' and each time you save the name is incremented by 1.

Using that method there's no need for a .blend1 file.

is there a way for only one backup saved?

See my updated answer.


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Strange wavy X shaped render artifacts
I'm getting an annoying wavy effect on renders in a low poly cycles file. Whats frustrating is that I've rendered several files now with all the same settings without this artifact. The strange thing is that the artifacts seem to appear only in the first room, not so much the second. The differences between whats effected and not might be these things

the first room is lit by an area light that the second is not lit by
the file is a copied version of another .blend that was then altered and it seems like the objects that existed previously are effected and the objects added after the copy are not i.e. the second room.
this is a low poly project and I don't want anti aliasing so blackman harris is set to 0.01 but this went fine with the other files.

here you can see the strange thumbprint artifacts
and here is later in the render, where this problem is absent

Let me know any settings that would be relevant. I'm using default denoising and have checked for differences in the affected objects with the unaffected ones in their properties to no avail but I'm not insanely fluent with blender.

Heres another picture clearly showing the problem

To me this simply looks like Moiré pattern. But since you do not provide any information on the material setup it's hard to tell what is causing this.

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

Those artifacts are called aliasing - a very wide term, with e.g. the Wagon-wheel effect as a subset of temporal aliasing. Another subset, as Gordon Brinkmann pointed out, is Moiré pattern. The logic is similar to Z-fighting (and perhaps it also qualifies as aliasing, though I didn't find a source claiming so) - two pixel neighbors bifurcate to two significantly different values based on some minimal (unexpectedly significant) input change.
One example of such bifurcation is rounding: you have two consecutive values next to each-other, but one rounds down, and the other rounds up:
>>> round(0.5)
0

>>> round(0.5000000000000001)
1

In case of z-fighting, which might be happening in your case, either of multiple overlapping planes is considered closer to the camera, based on calculation inaccuracies (which depending on the numbers crunched, sometimes will round one plane favorably, and sometimes another). To fix this, ensure no planes are exactly overlapping, and if some are almost overlapping, try decreasing the range of camera clipping (this range is divided into a constant number of subranges, so as you decrease the range, the subranges decrease and so the risk of two planes ending in the same subrange also decreases)

Another possibility is that your shader generates a pattern with cells comparable with, smaller or much smaller with the size of a pixel. While in reality looking from very far on a checkerboard texture results with grey color, when you use a single sample, the Checkerboard texture will only report one of its defined colors, so for a very big scale and 1 sample:

But 100 samples:

Different example:

 v=60
 v=25
 v=10
 v=3
 v=0.11
 v=0.000001
 v=0.0000001
There is no general solution to this (other than ANTIaliasing, which you don't want to use), you have to use such scales that boundaries between colors are further apart than 1 pixel.


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how to make that two different objects have the same number of vertices
I'm trying to join as shapes two objects that don't have the same number of vertices. The white shape is a FBX face object that come from the brekel pro face 2 and it contains the shapekeys / joints captured by the kinect 2. The other shape is the head of a character that I've created by myself. It contains no shapekeys,because I want that the shapekeys of the white face are merged into it. So,I have selected first the white face and then I have shift selected the character's face and I did "join as shapes",but the operation has not completed succesfully,because it said : selected meshes must have the same number of vertices. Is there a way to increase the number of vertices of the white face until that it has the same number of vertices of the character's face ? Or do you know another way to do that ? thanks.

It won't work even if you get the vertex count to match. The vertex order, placement and topology is different so your shape key would be just random garble. Join as shapes is meant to transfer keys between identical base meshes. Look into using Shrinkwrap modifier on the empty mesh to conform to other mesh with each shapekey, then apply the shrinkwrap modifier to shapekey. https://www.youtube.com/watch?v=YBvA2Hduk_w

If I give you my blender file,can you make a short tutorial ? it seems easy to do,but it isn't,at least for me...thanks.

You can practice with the shrinkwrap tutorial / other tutorials and try to make something with it to understand how it works. What you're trying to do with facial expression shapekey transfers here is not trivial.

please give me some other tutorial to follow.

plus,the empty mesh is the default character's face (it's my face),so I don't want that it conforms to the white mesh,but the reverse.

I need some help or advice. I use shape keys with a mirror modifier to make expressions for my model. But every time I apply the shape keys with the mirror modifier, I always end up with two more faces instead of one. I would be very happy with any help https://i.sstatic.net/uDZ2r.jpg


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Rigid Bodies instantly jump around upon starting the animation
I have a fractured object (pic 1) and on all of the fractures, I have a rigid body animation (settings in pic 2). The problem I'm facing is: as soon as I start the animation, all the fractures with the rigid bodies instantly start jumping around instead of just sitting there (they're on top of a plane with a passive rigid body setting on it). Why is this happening?

By jumping around do you mean fly everywhere and explode, or just bounce up and down?

@LWSSWL Jumping around. They don't go crazy. They just move around and I can't have them doing that.

You can prevent the fracture segments from activating until the frame where that's required...
Take a look at the answer here - https://blender.stackexchange.com/questions/215746/using-cell-fracture-the-object-that-is-supposed-to-break-explodes-or-breaks-bef/217727#217727

You probably should avoid using “mesh” shape when doing rigid bodies. It has an inherent margin and is not as precise as “convex hull”.

@TheLabCat: The mesh is the most precise thing you can do with rigid bodies. The convex hull does only work good on simple shapes which have no holes or indentations. Here you can see an example [1]: https://i.sstatic.net/a9miL.gif: left: convex hull, right: mesh. Same collision margins. The convex hull doesn't "recognize" the indentation. Maybe read this: https://docs.blender.org/manual/en/latest/modeling/meshes/editing/mesh/convex_hull.html

@ProEffectsMAX: it can be more than one reason why this happens. If you provide your blend file, we can say which reason it is. e.g. Overlapping geometries, too big margins...etc.

@TheLabCat: did you look at my video? stack these cubes and it is 1000x better. Now promote me!!!

or do you mean by "stability" just unrealistic!?

@TheLabCat : that’s why I wrote: convex hull only works on simpel shapes….


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Dynamic tesselation with displacement map
Is there a way to have an object automatically tesselated depending on the detail that is painted in the texture? I want to keep non-detailed parts low poly and detailed parts very highy subdivided. Dynotopo is doing this in sculpting mode.

(image from creativeshrimp.com)
I stumbled over the technique of vector displacement but this might be too advanced for what I need.


text:
Regional lightmap UV pack
Lightmap pack makes sure that no face overlaps and that each face is (mostly) scaled in proportion to it's real size and is undistorted. It also leaves a margin between faces.
However, this margin can eat up quite a bit of space in high-poly meshes:

Adjacent faces if the mesh face are smooth (which this example is) don't need a margin because the normal changes smoothly anyway. Also, a small amount of distortion is tolerable. Thus it make senses to pack regions of nearby faces together rather than make all faces alone. Is there an easy way to do this?


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Is it possible to slice a 3d object into many 2d images?
I made a script that turns images into Minecraft .schematic files so they can be imported as pixel art. A simple modification would allow it to use several files stacked up to make a 3D object. The issue is making all those images.
Is it possible to "slice" a 3D object (3D-printer style) into many 2D image files?
For example, slicing a sphere would give many individual image files. When played as a slideshow, they would show a circle expanding, then contracting.

It is absolutely possible to do this and I just covered the method in my upcoming book on OSL, in order to address volumetrics (given the pending support of OpenVDB or Field3D for them). It isn't exactly a menu option so much as a technique, but I suppose it could be worked into a plugin at some point.
What you'll want to do is set your scanning camera to face straight down (0, 0, 0 rotation) and put it at location (0, 0, 1). Scale your scanned model down to fit within the (-1, -1, 0)-(1, 1, 1) range. (Basically you'll want your setup to map every single slice of your mesh, and this is the active area for it.) You will want to set that camera to orthographic mode (not perspective) and set its orthographic scale to around 3.0; you may need to tweak this for the sake of your geometry.
Next, you'll want to add a cube to your scene matching that (2.0, 2.0, 1.0) scale, and make the following modifications to it. Set it to bright white, and go into edit mode. Add two slices to the cube with Ctrl+R and then rolling the mouse wheel up, left-click once, and then right-click to use the default adjustment. You'll want to scale them down along z to match your slice width. We're going to call this middle-of-sandwich space the "aperture". Then, select all four internal faces, and delete them; then (F)ill the space left between the edges of your two remaining capping shapes. The gap should typically be very narrow, you'll want it to be roughly 1.0/(number of slices) in height.
I've enclosed a picture of my general setup here.

The total number of frames rendered should be the number of image slices you want to get.
Now, you'll want to animate the aperture box to go from a starting position at (0.0, 0.0, 1.0) to (0.0, 0.0, 0.0). It should start moving at the beginning of your animation, and stop at the end, on a linear interpolation. Note that your aperture itself should be right on the shape's origin, and directly over the (0.0, 0.0, 1.0) coordinate; otherwise you'll have a skewed scan.
Lastly, you will want to add a Boolean modifier to your mesh, set to Difference mode, with your new clipping cube selected as its object. Here, I've called my modified cube "Clipping". That's effectively what it's doing—the only part of your mesh which will show in the render is the part that's between the two sandwich-slices of the cube, right on the aperture. Everything else is ignored because of this specific modifier.

Now, all you need to do is go to Output Properties and under the Output tab, give it a proper directory (since this is a whole array of images, I suggest a specific single-purpose directory per render). Choose your favorite image file format, and render. You will get an even-stepped set of images, of effective voxel size (2.0/[image width] x 2.0/[image height] x [aperture height]).
Obviously this method is extremely adjustable and tweakable, but this has worked for everything for me so far. The only modification you might need to make is the color of the background, and if you want specific diffuse colors you'll need to map them directly to the surface output in a shader. (Don't bother with emissive or diffuse shaders, just plug the color in directly—unless you want bloom screwing your image up.) By default, this is black on white. And—admitted shameless self promotion here—if you're interested in the full run-down and are interested in learning OSL, the book is "The Warrior Poet's Guide to Open Shading Language", completion and publication pending on Amazon. I'll have my actual Blend file on a public git repo eventually.
My general usage is to create a 3D coordinate space for volumetrics, where S and T map to image coordinate and P to image name. (STPQ is UV, when you need more than two dimensions, so it doesn't bump into W, which would be confusing and annoying.) Handy when you want to, say, map a shape onto a rendering of a cloud, or a liquid volume.
The thing to remember about Blender is that it's effectively a full-featured Python IDE at this point. There isn't a heck of a lot that can't be done with it anymore, if you've got the time and motivation to dig.


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Rigify feet controls generating wrong
I'm having two problems: 1. the heel control is generating on the front of the foot instead of the back, and 2. the red rectangle control on the bottom of the foot is offset forward. I really don't know why either of these are happening. I'm super new to rigging but the rest of the rig seems fine from what I can tell. Any help would be very much appreciated on either how to fix my metarig so it won't generate like this, or, if that's not possible, on how to correct the controls after generation.
This is what it looks like:

And from my understanding this is what it's supposed to look like (foot centred, with heel control on back):

Here is the .blend file

have you placed the heel bone of the metarig at the back of the foot on the floor? Here is the layout described: https://docs.blender.org/manual/en/latest/addons/rigging/rigify/bone_positioning.html#id12

Yes, it's hard to see because the picture's at a weird angle and the bones are set to be visible in front but the heel bone is in position as shown in the guide.

Ah okay, I see. Hmm, hard to tell what causes this. Have you applied the Scale to the metarig? Can you share the file? (Feet and metarig should be enough if you don't want to share the whole model for some reason.)

I have applied the scale to the metarig, yes. I've just edited my post to include a .blend file. I did end up just uploading the bottom of the mesh and the metarig because it seems like blend-exchange requires you to give away the unrestricted rights for them to use anything you upload?? Seems insane and super scammy but anyways... Let me know if you need any other info or more of the mesh. Thank you for trying to help :)

Your model is facing the wrong way. It turned by 180° along the Z-axis. The Front view (menu View > Viewpoint > Front or just Numpad 1) shows in fact the back of the character.
This confuses Rigify (might be a bug or oversight) and causes the foot control to go in the wrong direction, namely backwards from the character's point of view.
To fix this you need to do few things

rotate the model and the metarig. Select both and rotate them by 180° along the Z axis (R180ZEnter) and apply the Rotation (Ctrl+Z in Object mode). This will fix the orientation.
delete the WGTS_rig v3 collection and all objects that it contains. These objects are the shapes for the control bones. Rigify will re-create them, this time without the offset. The collection is disabled in the viewport. You need to enable the toggle button first (Filter dropdown > "monitor" icon), then you can delete them with a right-click > Delete Hierarchy.
re-generate the rig with the Rigify button

(Sometimes the control bones are too small or too big or hidden inside the mesh. Then you still can adjust them in Pose mode in the Viewport Display section. But these changes get lost when you re-generate the rig.)

Thank you so so much, I really appreciate it. That fixed everything. Helpful to know you can adjust control bones in Viewport Display too. :)


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How to scale out Vertices without changing the relative distance to one another
I want to move the center vertices outward without fattening the cylinders. The tops and bottoms should remain the same distance while the middle moves outward. When I scale the center vertices the cylinders fatten and it ruins the shape. I need them to stay the same thickness and slide outward along the x and y axis.

@DuarteFarrajotaRamos It has been fixed. Do you possibly have an answer to the question?

That is trivial to achieve with bezier curve objects, not so much with meshes

Do you want to keep the elliptical profile of the rods, or do you want them circular?


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I am trying to make procedural spines but they do not work each time I draw a new curve
I am trying to create a quick way to make spines along drawn curves but am somewhat new to geometry nodes. The circled spine was the first and the other three are new. Each one seam to act differently and I do not understand how to make them all act the same. The segments should scale along the length of the curve from bottom to top. What am I missing? Thank you in advance for your response(s).

instead of resample curve with count, try length. And please, next time use a node tree we can easily read...and even better: provide your blend file so we can test out our solution proposal. thx.


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How do I change the length of the secondary bone segments with Geometry Nodes
I am trying to make spines generated on a Bezier curve and have it 95% working. The rotations are all correct and the scaling is how I like it BUT I cannot figure out how to change the length of the secondary segments (smaller horizontal bones) to match the scaling factor of the main segments. I need to somehow sample the radius of the main bone segment mesh, then add a slight value to that, convert it to a vector format and then use it as input for the start and end coordinates of the secondary segments. But I am at a loss for how to do so.

When instancing, you can use the radius (or other calculation) to change the instance scales.


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How do i make an object emit an object that is emitting objects?
How do i get an object to shoot out an object that is shooting out objects with the particle system.

Blender 2.8 will have this feature, that will allow complex manipulation with particles (not only with particles):
https://www.youtube.com/watch?v=HQi2BqlQtnI
If you want to try something similar right now, you can try to use Animation nodes, but you need to know, that it has not so good performance as particles.


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How do I halve the width of a mesh while keeping it parallel to other edges (locking to an axis doesn't work)?

I want to flatten this cube and keep it a rectangle, all edges parallel.

I cant be sure the mesh is still aligned to the Local object axes from the picture, but if it is, switching  Transform Orientation to 'Local' in the header, and hitting SXX ( that is, tapping the dimension you're interested in, in Local space, twice) will scale the mesh along that axis.

You can change dimensions of a mesh by going to the Transform panel and input values directly into the fields under 'Scale'.
If you input 0.5 in the fields, assuming your mesh was already at Scale 1 for X, Y and Z, then it will be halved in all three dimensions while retaining it's current rectangular shape, it's position and alignment to other object and everything else. It will just become smaller.
You can also just change one or two of the dimensions and keep the other ones intact if you wish.

When i did that, they scaled to/from the point of origin(object center) and ruined the shape. how do i change the length of multiple edges that are equal by inputting a number?

I'm not too sure what exactly you want to do then. Changing the length of the edges will change the shape. What is your goal, what shape or size should the rectangle have when you're finished?

i want to stretch edges out while keeping them all parallel to each other. my object isn't a cube, and scaling isn't working, the object ceases to be parallel when i try


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Cycles Bake Issues
I've used Blender for several years now, but I haven't gone deep into anything. I'm looking at improving my current work and I've started using texture baking. So far I have a small understanding of it but I'm having an unusual issue with the bake results.
This is the original

This is the render view. I've built my materials and so on and, originally, I had metallic active. Because I have no idea how to use specular with Hl2's Engine I took it out and I'm using the reflective property.

The issue is that, no matter how I bake, cycles keeps doing this to all my diffuse, lightning or combine bakes. I've tried using a higher resolution image, adding environments, increasing samples to 800 from 138 default, remaking the materials, changed from 2.78, 2.79 and 2.80.
I've watched tutorials and look around and I seem to be doing everything right, the UV's are on 2048x2048 and are spread out.

But the result is always the same and it is stopping me from completing my work, because I cant seem to get a decent quality bake.


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Particle age acting weird (particle info node)

The colors are equally distributed in the color ramp node but, for some reason, the really bright parts are only shown in the first two frames of the particle age, as seen in the picture.
Even when I remove the color ramp and connect it straight to the emission, it comes out with the same result but in black and white.
How do I fix this?


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Missing brushes for Texture painting in 2.8
I downloaded Blender 2.8 and I wanted do some texture painting. But I noticed that there's only 1 brush in my Blender.

There was more brushes in Blender 2.79.

Where are all the brushes gone? I need them.

Hello and welcome. Please do not use caps in your titles. Using caps online is usually considered as the written equivalent of shouting loudly, and shouting is frowned upon. Thank you.

The tool has changed a bit, and things are now in a different place.
Simply, this in 2.79:

has become this is 2.8:

The latest builds of Blender now treat each of those brushes as their own tool - so  if you are drawing/painting, the default tool is that initial brush TexDraw and you will be able to make multiple versions of it that will now be handled as brushes. This is more in line with Photoshop and other software in that the blur tool, the mask tool, and the smear tool, clone tool, etc. are separate tools with all their own settings and functions. A better design that actually means we have to get used to the new tool paradigm, this also means it will be easier to manage brushes once we have the asset manager. You will be able to select the TexDraw tool and then in the tool properties select an individual brush there.

a little gift to complete your answer: https://i.imgur.com/1sNyNzC.png

Just open the tool menu by pushing U button.
then press X button


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How to select faces while using texture painting in 2.8?
I'm texture painting an axe, and there's a certain part of the axe that I want to select.

I only want to select that whole black sharp part, but I can't select anything while texture painting. I'm using Blender 2.8.
How can I select while using texture painting?

I guess you have this issue on Blender 2.8 because you're using the default Left click select keymap?
First things first:
In order to enable the face selection masking, push down that little button in the viewport header:

Then, in order to select the faces you want to paint on, use the ⎇ Alt LMB. You can also access some selection tools, like Border Select with B, or Circle Select with C.
For more advanced control of selection, you can switch to edit mode, do what you need and switch back to paint mode.


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Copying a detailed piece of a mesh and making it conform to the curve of a sphere
I'm making a model that has a ton of minuscule detail. I was wondering if there was a shortcut to copying a good detailed piece of my mesh and just pasting it to another section of it?
I've tried duplicating but my mesh is a sphere and at an angle which makes it hard to relocate the duplicate to another section.

Added image above^

I think the solution lies in the Array modifier.
Use the Array modifier on your detail, put an empty on the center of your sphere and use it for the Object Offset so that your details will follow the curve of the sphere.


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Script to remove faces with significantly different normals
I have a mesh imported from a Structure Scanner that has some dirty mesh sections. I have a script that imports, orients and simplifies the mesh to this:

However, looking from the inside shows that some faces are facing inwards, causing problems for another program along to process:

The scanner seems to double up some faces causing these problems. I can get away with deleting the erroneous faces/vertices (leaving holes to be filled in blender or the next stage), but I can't figure a way to detect these areas and remove them.
This solution from another question looked promising, but, firstly, I can't get the script to work and, secondly, it takes an average of the whole selection which wouldn't work on this nearly hemispherical shape.
Is there perhaps a simpler way of removing and correcting these erroneous points, CATIA has "clean non manifold triangles"?
Close up of one of the problems:

Answered based on title and script part. For cleaning suggest looking at Related

Just wanted to add that there is an operator bpy.ops.mesh.select_non_manifold()

A script to select verts based on the angle between normal and radial vector.

An alternative script than the one shown in question link.
In the case where the object is spherical, , after changing the object origin to the centre of the base ring if hemisphere (or where sphere centre would be), can then check the angle between vert  normal and vert coordinate (since vert.co is  also the vector from (0, 0, 0) origin). If it was a perfect sphere, all these angles would be zero.
Test script to run in edit mode. (In vertex selection mode) Change the 90 degree value of angle_check = radians(90) to suit.  The script only selects verts with an angle of norm to radial outside angle_check.
import bpy
import bmesh
from math import radians
context = bpy.context
obj = context.edit_object
me = obj.data
bm = bmesh.from_edit_mesh(me)
angle_check = radians(90)
for v in bm.verts:
    v.select = v.normal.angle(v.co) > angle_check

'''
# or by faces
for f in bm.faces:
    f.select = f.normal.angle(f.calc_center_median()) > angle_check

'''
bm.select_flush(False)
me.update()

You could try using the 3D Printing Toolbox add-on.
It checks your mesh for any bad geometry that would prevent proper printing, which includes intersecting faces, non-manifold edges, bad contiguous edges and so on.


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Mesh looking broken in perspective camera but okay in ortographic
I'm newbie, and I've been searching everywhere in YT and forums and I found no one with similar issues with me.
disclaimer I'm not so sure what's the issues here, the mesh/vertex or just the cam settings
Here's the pic.
In orthographic camera:

In perspective camera:

More info about the model:
I worked on viewport with 100mm focal length
The model is very high density. I remeshed until (?) voxel.
I know I should retopo but nope, ain't doing it for this project.
I noticed the broken meshes (or is it the vertex?) are the model for the clothes ONLY, except the top outer shirt
body/skin is unaffected; shoes, hair, eyeball is unaffected.
How I work on the model:
I made those skin tight clothes by using this technique: Mask select and extract. And then I solidify the thickness into negative (-0.01m) because I like the presentation better than the positive number.
I did not remesh or meddle with normals or mesh or merge vertex by distance, or any other mesh/vertex option or tools.

What I tried to do (ofc nothing work):
(feel free to retest bcs I might do someting wrong)

Flipping the normals
Solidifying to positive numbers
Hiding the body (thinking that the mesh is overlapping with the clothes mesh)
Changing the render camera focal length:
it's kinda working but not really what I wanted bcs it zoomed in too much
Messing with Cameras clip end setting

Hypothesis
I think it perspective camera will work with certain camera settings but idk where to start. I don't even know what is my situation called so I can't really search for this specific problem.
Also is this problem happened because my model is problematic? Or is it just simple camera setting issue? I need to know if I should change my sculpting method. How do I avoid this in the future?
Blender file

You really expect anyone to download a Blend file that's over 1Gb in size? That's a ridiculous size for just a simple model anyway.

Nope I don't. That's why I'm putting every details I could.


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I used to be able to get volumetric clouds to look decent but haven't been able to for this render
Using 3.1.0, optiX albedo/normal denoising just isn't cutting it for my volumetric clouds (which use noise > voronoi > absolute > map range > color ramp > mix value between a clear principled volume and a dense principled volume).

Everything else is denoising fairly well, but the volumetric clouds just come out as salt and pepper and look really awful even with hundreds of samples for the denoiser.

I'm rendering a hollow world with clouds inside and a sun at the center to make an HDRI for a DND map, so the clouds really need to recognizably clouds etc. I'm sure I'm missing something basic, it's been a while since I did a lot with Blender.

Edit: added photos of renders and of settings. My bad: I hadn't seen where to add the images so I just didn't.
If anyone has some higher-level feedback I would like to ask: Does anyone know how I might possibly take a sun and using shadow-casting objects and clouds reduce the light level to approximate full night-time darkness in the regions in shadow? The main obstacle seems to be all the indirect light (can I decrease that, is that something doable?) and that if I decrease the light level using dense volumes it decreases the visibility and drama.
Also, since the distances involved in looking up in the sky and seeing the other side of a hollow sphere the size of the earth should involve a massive loss of detail: does anyone have pointers as to managing decreasing levels of detail?

Hello and welcome. As it stands this question is unanswerable and was put on hold for lack of essential details to understand the issue. Risking stating the obvious, only you have access to your scene, so unless you describe it thoroughly you alone know your exact setup, settings and what steps you took to arrive where your are now. Describe the issue in detail, add images of relevant settings and user interface, with the [edit] button above. Don't post comments or ask a new question, editing will automatically queue it for reopening review.

What is your question exactly? Could you rephrase your post with a clear inquiry ending in a question mark so we can understand what you are trying to achieve?


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Curve Index of control point
I have a Curve object with two Splines and I want to use the Sample Curve node in conjunction with the Set Position Node to move the curve points. But with two splines all points are mapped to the first. Is there a way to get the Curve Index to which the control point belongs to feed that into the Sample Curve node?
Or other how do I find out what Spline the point belongs to / its parent's spline index?
Thanks for helping.

if you are using always curve index 0 - this is what should happen. Why don't you just enter values in the curve index depending on a condition of your choice? Since your question is very vague - i can only comment vague. Would be great if you could describe precisely what you end goal is. Also providing a blend file so we don't have to rebuild everything on our own would attract more people. Because usually GN is a very popular thing here...

The curve spline index can be accessed using the following nodes, that's what I tried to find.

I'm not sure whether you want the instanced points to move or the guide curves themselves. If you want the guides to move, you don't need the curve factor at all. Just feed a Noise Texture into the Position input of the Set Position node and animate its parameters. If, on the other hand, you want the instanced points to slide along the guide curve, you need a somewhat diferent setup. Instance your Ico Spheres on your control points, and connect a Set Position node after the Instancer. Divide the index by the total points count (use the Domain node in Spline mode). Feed the result into the Factor input of the Sample Curve node. Check the All Curves toggle, and connect the Position output into the Position input of the Set Position node. If you want to animate the points along the splines, insert a Math Add node after the division, followed by a Math Fraction node. Animate the other value of value using Time or keyframes. The Fracture node will make sure that the points jump from the end of the each spline back to the beginning of it in a seamless way.


text:
how to reuse the render result for second scene?
Ok, i am pretty unexperienced with multiple scenes/view layers.
I know i could solve my "problem" just with shader nodes - the question is more about a general workflow.
Is is possible to make a view layer/scene and use layer1/scene1 as basis for layer2/scene2? and how can i do that?
e.g. i have a scene with a colored photo. In the compositor i make it b/w. And then i want to keep on working with the render result and use this as an image texture for my cylinder and animate that cylinder (i assume in scene2...?)

so this is my first scene which just "makes" the image b/w ...but i don't know how to "reuse" now in my same project my render result for scene2.
I want to do this in one file.

Could you add a diagram or proof of concept of what you're trying to do ? I don't understand if you're talking about the render result or the actual objects in the scene ?

yes, i mean the render result

Have you tried plugging the output of the HSV node and the output of your second scene to a mix RGB ? When hitting render the first scene will render, then the second one and they will both be available in the compositor

https://i.sstatic.net/vAx8m.png ?

dunno if it can be done, maybe consider instead just rendering scene1, saving to file, using file in scene2?

@JordanSzubert: this is what i didn't want. I want to save time ;)

You should mention in your question that you do not want to save a file, which could be an option -> edit ;-)


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How to turn an attribute to an integer output with geometry nodes
I want to use a custom attribute as float/integer output, is that somehow possible? e.g. drive the radius of a Circle by an attribute.
Like this:

Do you mean a custom property on an object ? I think we won't be able to do it until they add the possibility to refer to object container properties, like the Attribute node in the shader editor where you can choose between geometry / object / instancer. You can do it with a driver but it won't automatically be linked to new or duplicated objects

@Gorgious: yes, i meant this! Yes, i hoped for something like this "Attribute node" in shader nodes. I thought/hoped this would be easy to implement ;)

Named Attribute? ...or did I misunderstand the question?


text:
How can I get a colored preview of all the blend files in the file browser?
Some of my blend file previews are shaded and colored. Most of them are just solid shaded:

How can I get a colored, nice shaded preview for all of my files?
fyi: i am using a mac...so a "windows only" solution won't help me.

did you color them in the Material > Viewport Display?

Äh…no…cause I didn’t know

That's a really good question. I really don't know, I only know it has neither to do with the Shading Mode in the moment you are saving the file, nor if the material has a given color for Viewport Display, so that it looks colored in Solid Mode. Or if any of these factors have an influence, I cannot willingly decide what I want to see in the thumbnail by changing any of these settings.

@moonboots: Gordon is right. Viewport display doesn't work :( or do i have to set something special?

If I give a color in Viewport Display, the file icon will display a color when I'll try to open it, but it may not be what you're expecting

@moonboots: i want a colored preview of my blend file as shown in my pictures. Not just a colored icon ;)

I mean the object is colored like that: https://zupimages.net/up/21/26/ccwx.jpg

äh...possible duplicate ♂. https://blender.stackexchange.com/questions/170712/how-to-have-color-in-your-blend-file-preview

the answer you link cites the Viewport Display color, not sure what he meant with Random color though, it doesn't seem to change anything

i am just trying...but his answers seem to work...

so that was my answer as well  ^^  Material > Viewport Display

@moonboots: yes, but you "forgot" to mention that the material shouldn't use nodes... ;)

mmh, works with nodes for me...

if you once put the nodes to "not use nodes" and put them on again - then he "kind of" shows the colors from "before" -> the behaviour is a bit weird....but if you "use nodes" at once you won't see any color. Just try out with default cube, use nodes, give color and save.

I'm not sure to understand but OK  ;)

if you are really interested i can make a yt video to show you ;)

I don't think the Use Nodes is important, I figured out an answer though it might not yet be the complete "magic" behind this all...

EEVEE:
You get colors in the preview, if your objects have materials which don't use nodes (this is the case when the "use nodes" button isn't checked).

or if you choose a color in material -> viewport display. Then this color will be shown in the preview.
But...there must be some other possibilities, because i see more colored previews with different settings...
If once set your materials to "not use nodes" and the preview was colored, you can set them back to "use nodes" and the previews will stay colored.
Ok, one new "rule" i found out:
If you uncheck "use nodes" and set a color, this color will be used in the preview.
If you then check "use nodes" it still will use the color of the "unchecked nodes" color in the preview.

That seems odd... as if the thumbnail preview is saved at some time and doesn't get refreshed - or refreshed at some (random?) intervals. Does this mean if I change the objects in the scene, the thumbnail won't show that either? Well, switching all materials to not use nodes to have colored thumbnails is definitely not worth the effort for me, if that's the solution :D

@GordonBrinkmann: The preview will be refreshed whenever you move/add a mesh object (i just tried) but the colors won't. So i think i you start a new blend file, this might be a solution. For old blend files...for sure not ;) I am also not sure whether it is a bug because it's seem to be weird...

This "Use Nodes" option is not available in Cycles, so to get your Cycles file colored in thumbnail there must be another way.

oh sorry, yeah, i just tried out eevee so far. i will adapt my answer

Okay, this seems tricky. The linked answer to the other question here is only "half the truth". The following I found out for both Eevee and Cycles, although it seems like @Chris pointed out, that option 2. below is not working on Mac, only Windows.
In the Viewport Shading settings you can use the following three Color options if you want a colored thumbnail preview:

Material: This will show the color you've set under Viewport Display in the Material Properties.
Object: Enabling this will show the color under Viewport Display in the Object Properties.
Texture: Now here comes the tricky part - if you choose Texture, the thumbnail will show the last Image Texture you've selected in the Material. If you select some other Texture Node like e.g. Musgrave, then the preview will show the Viewport Display color from the Material Properties.  My guess is, this texture preview doesn't work with procedural textures, only image textures. Also it will always show the image mapped to the UVs at scale 1, no matter if you use other texture coordinates or maybe scale it up or down.

That said, there is still room for further investigation I suppose but that's a first approach on getting colored thumbnails where you can decide what colors you want there.

And here how it turns out using Material (the object on the right has two different materials):

I've chosen different colors in the Object Properties so this is how it looks if I switch to Object:

And if I now switch to Texture and there is an Image Texture selected or you select one afterwards, at first this image is shown on the UVs of the object. And the preview won't change if you select the Mix RGB or Texture Coordinate notes afterwards:

However, if you select a node which is found under the Add > Texture menu in the Node Editor (in this example the Musgrave texture), the shading preview will now show the Viewport Display color set under Material Properties:

Here are the thumbnails:

sorry, but point 2 does not work  -> preview won't change its color. Your answer sounds like "if you change to object your preview will take the color of object properties -> viewport display" but it does not. It always take the color for the material -> viewport display

It works. If you change the Viewport Shading Color to Object, the thumbnail will change its color if you have set a color in the Object Properties.

not in my version. 3.0.0 alpha on mac

Well, I base my answers on stable official releases to make sure you're it's not subject to change... unless I want to point out differences between official and experimental releases. And if the problem depends on the Mac version, I only have Windows so I can't try that, sorry.

and 2.92 doesn't work too

I've edited my thumbnails in to show it working... I've tried 3.0.0 Alpha and it works there, too. Maybe it's Mac-related? I mean, Windows has its own thumbnails system so maybe they are in a way different that make it not work under Mac? But anyway, since you have Material and Texture there are still options to get your thumbs colored.

i believe you that it is working for windows...but it doesn't work on Mac. That's all i can tell.


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Why does the stethoscope node not work inside groups in Sverchok?
Sverchok: Does anybody know why the stethoscope node doesn't show values inside a node group? Or does some workaround exist? (yeah, of course i could have the nodes "outside" the group...i know ;)

I think it's the same issue for which we didn't have ctrl + shift + click with node wrangler in the shader editor, a node group can be instantatied any number of times in any node tree, and I don't know if there is a way to know exactly when its logic is ran, and for which instance the inspection node should show its values. I don't know the in and outs of all this though, so it's pure speculation :)

My note is also blurry :) and doesnt have to relate ... it just happens from time to time to me - since nodes are closed into group, node tree provides some  disfunctions.

Ok, i asked this question on github and they answered:
you found an unfortunate corner case for monads ( a very early and primitive implementation of Group Nodes for sverchok); namely those two nodes:
-frame info node
-all nodes that draw openGL-type instructions (either to nodeview (stethoscope..) or to 3dview..(viewer draw, doesn't create a Blender mesh in realtime it only draws a mesh)


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how can i change the blend mode to alpha in 2.79
In Eevee in newer versions you have to change blend mode to Alpha blend if you want to use transparency.
How do you change this blend mode in former version before 2.8? So how can i do this in 2.79 with Blender Render engine? (thanks Jachym)

Hello :). Since Blender 2.79 doesn't include Eevee, are you asking about the Blender Render engine? :)

ooppps, sorry for my "not knowing" - i started learning Blender with 2.92 :( ...and....yes, i must have meant this! ;D

And for Cycles: How to see Cycle's material transparency in 3D View

thank you!!!!!!


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how to change fcurve for material value
So i made these funky cool material ;) with a custom node group and an input value, which i like to animate. Works. But...
I cannot see in any animation-change editor the fcurve so i cannot change it which i would like to do. Is this possible? if yes, how?

Click on the group node so it's active. The fcurve should show up in the graph editor. Is that what you mean?

Can't reproduce. (Yet.) Are both the object and node-group active, when you attempt to see/modifiy the f-curve?

thank you both!!!! i am too silly. My object was hidden, so i did not select it. works!!!


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Hair works in viewport, but won't be rendered
I have this blend file:
https://www.dropbox.com/s/zj42em9ia5fa91s/running_mixamo_animated_hair.blend?dl=0
and it works in viewport and i can successfully render the viewport animation.

However whenever i try to render this, it simply does not work. It renders this:

my settings:

maybe it is important: i use multiple cameras (although i don't believe this causes the problem)

Which Blender version do you use? If I open it in 2.92 there is no visible hair in the viewport. I have to clear the cache and switch the type from hair to emitter and back to hair. Then it's displayed... (?)

thanks Blunder. it happened in 2.92, 3.0.0alpha and 2.93. For me it looks like the hair "thing" is pretty unstable because although i did this what you said and cleared cache...only sometimes it worked. But more often it just showed no hair. And often Blender crashed. :( As i said - i see hair in the viewport, but not when rendering


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Rotation Value ist not the same as given in the driver output
I am just trying to set up a dynamic circular array of objects. To keep it as dynamic as possible, I want to make my helpers empty z rotation driven by a driver. The Scripted Expression looks like this:  360/count while count is the count value set in the arrays modifier on my object.
The final value calculated in the driver is correct.(45 in case I have a count of 8). The actual value set in the rotation property is different. See the Screenshot below.

Am I missing something?

While all angles entered into the transform input field are interpreted as degrees, when you set the value in a script or driver it's interpreted as radians.

Your driver sets the rotation to 45 radians which is about 2578 degrees. The expression 2*pi/count should provide you with the desired angle.

or radians(360 / count)


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How to see/change vertex weight of vertex groups create by skin modifier?
i made an armature by skin modifier -> create armature.
Can i somehow see and change the vertex weights of the created vertex groups?

Yeah, this is a problem.  Most operations of weight paint won't even work if we try to weight paint a mesh that has no faces.  If we take a vert string and try to do a weight paint gradient, we won't even get an operator box, much less any change in weights.  And that's ignoring the fact that even if we could change the weights, we couldn't see how we changed them.
I haven't found a good solution to this, so here's the best (not very good) solution that I've found instead:
Add some faces to your string and use a mask modifier to get rid of them before the skin.  Once we have any faces whatsoever, even if they're being masked away, we can paint weights.  We still can't see them, not while the mask modifier is active, but we can paint them.
If we need to see our weights, we can disable the mask modifier temporarily.  This is far from ideal, but it's what I've got.

love that work around!! +1

The modifier Skin creates an Armature from the edges of a mesh and additionally creates a vertex group for each bone.
You can see and edit the weight of those automatically created vertex groups when you switch the object interaction mode from Object Mode to Weight Paint in the upper left corner of the 3D Viewport.
If you then select a Vertex Group in the Properties under Object Data Properties, the corresponding weight is displayed and you can repaint it.

EDIT: If you want to draw directly on the mesh that the modifier skin has created (for example, if you used only vertices as a starting point), then you would have to apply the modifier first:

Alternative solution:
Another way to influence the weights without applying the modifier Skin is to simply use the Bone Envelopes instead of Vertex Groups.

For this you would only have to change the value Bind To in the modifier of the Armature to Bone Envelopes.

Ähm….if I go to weight paint, I just see the edges….without weight paint. I know how to see „normal“ weight paint and I don’t see a skin modifier in your example. I just use a vertex, extrudes that, then added skin modifier and pressed create armature. i added a gif so can can see what i see/made ;)

Um... yes, that's right, with your screenshot it is all a bit better understandable ;-)

Ok, that’s sad. Hoped for another possibility.


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different output in rendered view and material preview
I tried researching for question How to apply material correctly to such kind of shape?.
So i made this:

which looks like this in material preview:

but in rendered view my textures are "gone"!? what can cause that?

blend file:

Hello, in Rendered mode it will reflect the image called je_gray_02_4k.exr but you haven't shared it

oh sorry, will correct that

blend file updated

Possibly a bug with GN? I added a new cylinder and modeled it directly then added your material to it and the textures appear fine.
Also setting to Eevee the textures are fine with your models

@Psyonic Not really a bug, I'm working on the answer.

ok....waiting......... :D

@Psyonic I guess it works in Eevee for the same reason (whatever that might be) why it works in the Material Preview, since the Material Preview uses Eevee.

@Chris What are you waiting for? It's been ready forever now :D

The problem is the attribute name you are using. You have a Vector output in the Geometry Nodes modifier that's called "uv", and that's the name you are using in the Attribute node in the Shader Editor. I checked if there is some spelling error or anything but it's all correct.

You also have a Texture Coordinate node in the material. I checked all outputs and all of them showed the texture (incorrectly mapped, but visible) excluding one: the UV output. It actually looks like before with the attribute.

So I got the idea that maybe the Cycles render engine uses the attribute uv internally for the UV map? The Material Preview works with Eevee, no problems there as it seems. I have no idea about the details inside Blender, but I just made a little test and decided to rename the attribute to "test" in both the modifier and the material and then it worked (in the object to the left I changed it before making screenshots):

@Chris It looks like it might be best when using attributes (and you can't find a reason it doesn't work) to not give them meaningful names making sense, but totally crazy and absolutely unrelated names to ensure they are not colliding with some other attributes :D

wow, chapeau for finding that!!!

@Chris ...but I'm really curious what the real reason is. Is Cycles actually grabbing the UV map when you use the attribute name? And if so, why doesn't Eevee mess it up? Why can Eevee distinct between them?

I have no clue…♂


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How to scale a rigged object just in z direction?
Bloody rigger beginner here:
So i successfully rigged my little cube here:

Now i wanted to have exactly the same just with half z height of that.
So i saw another answer here on SE and the answer said: scale down the root bone.
So i scaled down my root bone on z by 2 (so the scale z value in pose mode is 0.5)
result:

Nope, that's not what i wanted :(
I think you pro rigger know how i wanted that, right?
What did i make wrong?

Does this answer work for you? (Scale the rig not the bone)

Does this answer your question? How to scale a rigged character to a new height?

unfortunately...no. i tried that. Didn't work :(

post the rig and I'll take a look

posted it.......

Two armatures and bone parenting instead of vertex parenting is just a bit much for me.  I made it work by scaling both armatures and not applying scale, but I think that will give you problems later.

@MartyFouts: For me personally i think direct parenting of mesh to bone is much easier than with vertex weights ;)

Let us continue this discussion in chat.

This is the procedure for what (I think) you wanted:
Select bottom face of the mesh and use Shift S to set there the 3D cursor.
Set 3D cursor as pivot point.
In pose mode scale Upper and Lower bones in Z by 0.5.
Select top mesh and use Alt P clear parent (Keep tramsform).
Same for bottom mesh.
Apply Scale for top and bottom mesh.
Select Armature in pose mode and use Ctrl A Apply pose as rest pose.
Bone parent the meshes to the relative bones.

i got it working, thank you very much. Is it possible, that i had to apply visual transform to pose? because if i chose pose as rest pose the cubes got big again...

You have to do it after clearing parentship (and keep transform).