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How to have duplicated meshes with different vertex groups in 3.0+
I have been working with 2.91 for a long time because I have a particular modeling/rigging method that involves duplicating meshes, and altering their vertex groups for use with different bones in a rig- it works as long as each duplicated instance of said mesh has the same amount of vertex groups, in the same "arrangement". This process is particularly useful when it comes to designing machines/robots, as well as any generally repeating shape such as arms, legs, fingers, etc.
The problem however, is that this "feature" was patched out in 3.0+, meaning I would need to have a unique mesh for each instance of a part throughout the design. It's not too much of an issue if I have already compiled everything into a singular united object, but for the general WIP stages where I may potentially need to edit topology or UV maps at any time, this is a major setback as it would require me to try and edit all of these similar pieces at once.
I even remember when 3.0 first came out and this broke my process, I asked around in a modeling group and they just told me that I was effectively working with black magic.
For example, here is one of my character's hands. To be extremely blunt, this is a very intricate design with lots of mechanical detail. This one section alone is nearly forty objects, all spread over eight, maybe ten duplicated meshes.
The list of parts is (Hand), (knuckle), (finger A), (joint), (finger B), (finger C), and (cables)
Meshes like the finger parts have only one vert group, but the knuckles and joints have up to three.

Of course when I try to open this file in 3.0+ (in this case, 4.0) then the whole thing practically implodes- out of the 10-20 duplicates for each mesh, each with their own specific vertex groups, only one setup for vertex groups actually works, and is enforced across every other instance.

If there were a way to have a similar process in 3.0+ or even 4.0, I would gladly appreciate it.

There are a number of ways to do this.  You could data transfer, you could use GN modifiers to re-assign VGs, you could script those, or you could use independent armatures so that you didn't have to rename VGs at all.  It's unclear to me if you're asking to fix your existing technique or replace it, but if it's to fix, we'd need to know what the technique is.  The problems you're showing in your last pic look like more than just VG failures though

Reading this comment and the below answer, I am using the Alt-D linked duplicates. To clarify, my modeling/rigging technique heavily uses linked duplicates, and I am somehow able to have duplicates with different vertex groups. That is no longer possible in 3.0+, which is what I am asking- how can I have the equivalent of linked duplicates with different vertex groups? The key point is that I want these duplicates to share the topology and UV maps of the original piece: I make any edits to one and it automatically carries over to all of the other copies.

Linked duplicates alone won't rename your VGs, not in any version of Blender, so there's something unmentioned to your technique as well.  Rumen's existing answer is a reasonable way to reassign VGs (although it is painful, and reduces much of the versatility of using linked duplicates.)  The precise method I would use would probably depend on my needs-- what is my rendering engine/am I exporting?  What does my armature look like?  Etc.  I'm loathe to give any alternate techniques without knowing that info-- I don't like hearing, "Actually, for reasons I didn't mention, that won't work."

I just whipped up a super quick and rough example of what I am dealing with, it's a basic torso with two arms, and three-fingered hands. In 2.91 it works entirely as intended, and in 3.0+ the linked duplicates all share the vertex groups of only one of the copies, and thus the whole model collapses.

If it helps, I have a third-party program that lets you download older/newer versions of Blender. My default is 2.91, but I've been using the launcher to open 3.5 and 4.0 for testing whatever I could between versions.

Thanks!  I've detailed some solutions below.  I actually have a copy from 2.9-ish around anyways (hunting down a bug), but Blender Foundation also keeps old releases around at https://download.blender.org/release/

If I understand correctly you duplicate your objects by linking (Alt+D)
So you'll get objects having the same mesh data and the same vertex groups like on the image bellow:

Left to Right - Original object, Linked (same mesh, same vertex groups), Duplicated (different mesh, same topology, similar order of vertex groups)
To test the objects I added 3 Displacement modifiers for each of their vertex groups.
The vertex groups of the independent third object is altered as can be seen above.
If you want having the Vertex Groups data mapped from the third object to the second (linked) object. You can do this by adding Data Transfer Modifier before your deforming modifiers. This way the shape of the linked object is still controlled by the original mesh, but the VG data can be read from another template mesh.

As long as the meshes are topologically equivalent and the vertex groups are in the same order (or name) you can easily transfer the vertex data with this modifier.
Here is a closer look of the modifier settings

Make sure Vertex Data is enabled with Vertex Groups - on, Mapping is set to Topology and Layer Mapping is set to By Order (or By Name, if you are sure the names of the vertex groups match).

It appears that, sometime prior to 3.0, Blender stored VGs on mesh data only as indices to VGs and values for those indices, while the names were stored in the object-- the names, as object data, were individually editable.  This probably changed as part of a push to get GN to work properly with VGs.
I can see how this would be described as "black magic"-- it relies on undocumented design decisions in Blender, which of course can change, did change; and it can lead to some unexpected results sometimes (like sorting vertex groups also sorts vertex groups on linked meshes, with differently named VGs.)
If you need to use a model designed like this in current versions of Blender, and you no longer need to edit it, you can "make single user"->"object and data" to unlink the meshes, then save or export or copy/paste into a newer version.
It seems to me that your goal here, with the use of linked meshes, is for the purposes of editing.  There are a number of ways to maintain this kind of edit-once functionality, and not all of them involve linked meshes:

Mirror modifier.  This is appropriate, in lieu of linked duplication, for anything that you're going to mirror over a single plane.  On default settings, it automatically renames *.L groups to *.R and vice versa.  You can specify a mirror object (usually, an unrotated empty at the world origin) to override existing object transforms if you want.

Bone parenting instead of armature deformation.  This is appropriate for any objects that are weighted to only a single vertex group.  Since parenting is object data, not mesh data, each linked duplicate can have its own parent.  This is usually accompanied by significantly better performance than armature deformation, as an added boost.

Multiple armatures:

The only restriction on bones with the same name is within a single armature.  If multiple armatures are used, then vertex groups don't have to be renamed in the first place.  You can just duplicate the armature (linked or not) at the same time you duplicate the mesh.  Then, these sub-armatures are bone parented to bones in another armature.
This can complicate some rigging techniques, and it's not easy to "fix" it back into a single armature without scripting.  It won't export well.

Dynamic assignment of VGs.  This is the use of any kind of modifiers (data transfer, vertex weight edit/mix/proximity, geometry nodes) to reassign vertex group data.  Rumen Belev has mentioned the data transfer modifier as one example of this.  Data transfer is appropriate sometimes, but it limits edits that can be made to the meshes (without corresponding edits to the data transfer object.)

My preference, for a-bomb level reassignment of vertex groups, is to use a geometry nodes modifier:

In this case, the prototype has all of the vertex groups that we'll ever want on any of its linked duplicates, and we use the modifier to assign left to right and vice versa.  Once made, this modifier can easily be copied to any number of objects, but the parameters for each object should be individually specified.  This particular example switches two vertex groups; you can make it switch any number you want, and you can leave parameter fields empty if you want to use a modifier that swaps many number of groups on an object with few groups.  But, there is the tedium of actually setting up the modifier and filling its fields.
It's possible to do the same kind of thing with vertex weight edit and mix modifiers, but the GN way is a lot easier, a lot cleaner.

I have attempted #1 before, it's usually better for parts in the center of the character/model rather than further out like fingers, toes, etc. I have heard about the bone parenting in #2 before, it's interesting, but many of my parts have more than one vert group. I have attempted #3 when I had first started modeling in 2018... it was gross, haha. #4 looks promising however, though it seems like it may effect performance in regards to larger projects like what I had first shown. I'll try looking into it later today, though.


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Objects origin is not moving in edit mode
I probably messed up some of the settings but I couldn't figure it out my selfe.
The problem is, that when I move the wohle mesh in edit mode the objects origin isn't moving with the object, but the pivot point is nevertheless still in the objects center.
And the reason I think the problem lies in the blender overall settings is because I started a new project and tried the same thing with the default cube. The problem is still the same.

No, that is intended, and important.  The object origin does not change with edit mode changes, only with object mode changes.  The reason that the center of edit-mode transformations change is because those are not centered on the object origin unless you use a cursor pivot, centered on that origin; they are probably using the median vertex position as the pivot instead.

Pivot Point and Object Origin are different things.  The Object Origin isn't meant to move in edit mode.  The Pivot point depends on the Transform Pivot Point setting.  Take a look at the top bar in the 3D window:
The second drop down sets the pivot point:
You haven't screwed up any settings.  You just have the Pivot Point set to "median point". Because you have selected a cube, the median point happens to be the center of the cube.
If you want to pivot along the object origin, change the drop down to "Individual origins".
To move the origin, in object mode, Right Click and select "Set Origin" from the popup menu

Would change this slightly to "because you have selected all vertices of cube"  .... as opposed to result of  (median point location) with one vert, one edge, one face selected etc.  (also individual origins will probably not be the object origin location)

Good point. I wasn't sure how much detail would be overwhelming.  One could write a longish essay on pivot points, coordinate spaces, and their interactions.

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Extrude from the vertices
I tried searching this online, but didn't know what it was called, so had some hard time finding anything related.
Just wondering if anyone know how I can turn a flat surface, where the edge and vertices are linked, and extrude it from all sides from the vertices to give me something like below?
Thanks.

https://blender.stackexchange.com/questions/144828/is-it-possible-to-split-a-vertex/144831#144831

You can create this shape relatively easily using CtrlShiftB to Bevel Vertices with 2 segments:

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Fill Spline based curves efficently
As you can see on the image below, I got a lot of vertices after converting the splines to a mesh. The splines a drawn manualy from an old map.

I already started with the filling process. Selecting two edges and fill them with Fwas not a solution, since it causes weird looking artifacts.So my second attempt is to select "nearest" vertices manualy and fill a edge between. This seems a bit tedious and a lot of work.
Does anybody have a good approach to this?
I have a silly Idea in mind: Using a clothing simulation to fall down on my splines and use the fianl result as my shape. Does this sounds like a good Idea?

You can select 2 vertices and create an edge as shown on your screenshot.
Then active edge selection mode (2), and spam F which creates faces until the end of the spline is reached. Select the whole spline by pressing L (Select Linked), then remove all faces (X, Only Faces)

Thats a very good hint. Is there also a fast way to create an equal number of vertices on the "curves"? and spread them even?

I used limited desolve which worked great. The manual workload is reduced drasticly and the result is looking great.


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Efficent way to let objects appear/disappear
I have some objects which I want to disappear, if they are out of view. I used the technic to keyframe viewport and render visabibilty. The main issue I have with this technic, if I want to scale my keyframes or move the keyframes it works until they disable the visability. So in Frames in which the object's visability is disabled, the keyframes are also disabled.
My workaround for now is to apply this step in the very last step. I also tried only to change visability of render, but this makes it difficult to analyse the Animation in viewport. I think this is kind of unneccessary and I hope a better solutions exists.

Use this button to view the keys from objects currently hidden:

Also, consider looking at object culling if you are using cycles, that hides objects that's out of view or far away, automatically in render. Object culling should be enabled both in render and object settings for each object that's going to be culled.

@Crantisz Important would also be to disable Show Only Selected left to where your arrow is pointing at - because as soon as the object is invisible in the viewport, it is no longer selected. You have it disabled, but it should be mentioned since it's not the default.

@MartyFouts The OP is talking about seeing keyframes. It is literally stated in the question that the problem is, keyframes will be invisible as soon as the object is invisible in the viewport, but leaving them visible in the viewport makes it more difficult to analyze the animation in there since the objects don't disappear then.

@MartyFouts Quote: "So in Frames in which the object's visability is disabled, the keyframes are also disabled." Actually it is not literally said that the keyframes are invisible, but that's what they are when they are "disabled" because the object's visibility is disabled.

@GordonBrinkmann You're reading implications into the OP's statement by your own admission "it's not literally said".  Ask them what they really mean.

@MartyFouts You know very well that people not always find the right words. You can disable keyframes i.e. make them not contribute to the animation result, but this is not what happens when the object is invisible in viewport. They are invisible but still contribute to the animation.

So to short the discussion a bit since @Crantisz Solution was in the right direction. I actually was using the visability mostly for culling (I didn't realized this feature yet), but also for making an Object disappear after I hided it with one-directional mirrors. So his/her solution was not perfect since the Show Only Selected must be disabled to show my disabled in viewport Objects. This makes it a bit tidious, since I have to manage all keypoints at all but much more reliable than my workaround.

@MaKaNu I agree it's tedious, I don't understand why it operates like this. Disabled curves (by unchecking them in the Graph Editor) are still visible (only greyed out) but have no effect. On the other hand, if an object is invisible the keyframes are too, but still their settings affect the animation - at least while visible. That's confusing. But despite that you can select invisible objects in the outliner and properties like materials etc. are still shown in the Properties tab. It doesn't make much sense, if I want to exclude keyframes in Graph Editor I'd simply unselect the object.


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Not working any more
I use Windows 10
Switching to fully guarded memory allocator.
Blender 2.80 (sub 75)
Build: 2019-07-29 09:41 AM Windows
argv[0] = blender
argv[1] = --debug
argv[2] = --python-expr
argv[3] = import bpy; bpy.ops.wm.sysinfo(filepath=r'AppData\Local\Temp\blender\debug_logs\blender_system_info.txt')
read file
  Version 280 sub 39 date unknown hash unknown
AL lib: (EE) UpdateDeviceParams: Failed to set 48000hz, got 44100hz instead
Error   : EXCEPTION_ACCESS_VIOLATION
Address : 0x5801B2C4
Module  : C:\Windows\SYSTEM32\atioglxx.dll

That looks like an issue with your graphics driver. Try to update it to the most recent version and check if that fixes the issue.

Should be posted to [SU], this deals with system issues (e.g graphics drivers)


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Grease pencil "Failed to find" materials with line art modifier on a blank stroke with Blender 3.1
Update, it is not a bug.
I had changed Preferences->Editing->Objects->New Objects->Link Materials To: Object Data to just plain Object.
But, "Modifiers only affect the Data, so it's understandable not to use Object materials in modifiers."

I'm not sure if I am doing something wrong or if I should report a bug. Be aware that the only way I have been able to get Blender working right again is to reload the default preferences.

Add a blank grease pencil stroke to the default scene.
Add a 'Line art' modifier to the stroke.
Click on the Material slot of the line art modifier and then click on the blank pop up where a black material should be and you should get a Failed to find '' error.

With Blender 3.0.1 I get a default black material for the blank stroke.
Should I just report this as a bug?

Looks like a bug. Did you by any chance modify the startup file ?

It first happened after I made some changes with the startup file. But to check it out I set the startup file back to default and went from there. I could find anything about the problem online so I'll try filing a bug report.

Sorry I did not get if reverting to default fixed the problem

I didn't explain right. If you don't run File -> Defaults -> Load Factory Settings the grease pencil line art modifier won't work anymore.  If you add a stroke or suzanne grease pencil object the line modifier will find the materials for the objects and you can continue on.                                        https://developer.blender.org/T96349

Alright makes sense thanks for the bug report. Cheers

It was not a bug, I had changed Preferences->Editing->Objects->New Objects->Object Data to just plain "Object". But, "Modifiers only affect the Data, so it's understandable not to use Object materials in modifiers."


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I can not make library overrides work for probs making such as cables with splines
I am making a range of probs for a production. When it comes to large scenes I used a lot X-Ref or instancing and referencing.
In Blender the (new) features for this is "library overrides".
You can reference object blocks and data blocks but also override them.
Though I can not get it to work.
Here is a short explanation of the issue:
Video showcasing the cable tray and issue at hand

Any help and best practice is very much appreciated.

You should describe the steps you did as you leave us guessing.    Perhaps References.001 is Linked into this file as a Collection?   Then you selected the Collection and did an Object -> Relations -> Make Library Override... ?   What is the Disable in Viewport set to in the original file that you linked, or in this instance?   Then did an Object -> Relations -> Make Local -> ____ ?   (Gracias to Duarte, for removing the (obvious) "Need Help" from the Subject and adding library-overrides to the Tags

Hey James, perhabs I should have made the video link more obvious. It illustrates exactly that as it is a much better format to see what may be the issue. I saved the file. Opened a new file, linked the scene via import-> link->scene. Then I tried to do exactly what is shown in the blender manual and wento to object -> relations -> make library override. I also tried the same process with linking not the scene but the objects, or the collections or just the mesh mesh data. But none seemed to work. Lastly I tried to just make everything local. But sadly it did not work. Thanks for the help.


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Distribute Points on instanced geometry
I want to instance a leaf on my instanced stems. But it only shows the stems.
Is the geometry output of the Point Instance node not treated as full normal geometry?

I suggest you include the leaves inside the stem object. You can use the same technique twice. You should use a random seed on the leaves, otherwise all the stems have the same leaves. Distribute this stem-leave object on the floor. This should work.

yes that`s what I did but there was no option to assign a random seed per stem instance

Mmm... Maybe you could use the object's location as a seed? I know that the geometry nodes are still under heavy development, so I rackon it will be a thing of the future. Either way, you could always make 3 or 4 stems with leaves and randomly spread these on your plane.

The location as seed did not work... I will go the long route and just create a batch of stems thanks...

The correct answer is: add a "Realized Instance" node then "Distribute Points on Faces" then "Instance on Points". This worked for me on Blender 3.0.


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Geometry nodes Controle point scale with z position
I want to distribute points on my mesh but scale them so they get smaller the higher they get.
I think that we can do this by using a color ramp but I want to separate my position values and clamp the z value so I can properly use it.
For that, I would need a way to feed it into a separate XYZ node but I can't find a node that outputs the position per point to use it later.
This is my current state:

Well, you just need the fresh build of 2.93 alpha.

You can find Attribute separate XYZ here.

Thank you, will go right ahead and download it


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Change default_frames_limit trough Text Editor script
I want to change the default_frames_limit in the movie clip editor. I found a script in a addon that does exactlie that:
clip = bpy.context.edit_movieclip
clip.tracking.tracks.data.settings.default_frames_limit = 10

But it just works from within the movie clip editor, not from a text editor script.
How could I change this value from a different context?

I guess you'd like to run your script for a movie clip which is already loaded into the editor right? If so, I'd suggest to write a custom operator to call your "script" from F3 or to add a button to that editor, related: https://blender.stackexchange.com/questions/167862/how-to-create-a-button-on-the-n-panel/167870#167870

Thanks for the link might work it into a fully-fledged addon, fo now the answer below was helpful.

Its the clip associated with the space.
Similarly to a text in the text editor, an image in the image editor, what is known as the context.clip in the movie clip editor, is the clip assigned to the space.
To the python console:
Loop thru the screens to find a movie clip area and return its active space.
>>> def get_clip():
...     for s in D.screens:
...         for a in s.areas:
...             if a.type == 'CLIP_EDITOR':
...                 return a.spaces.active
...     return None
...
>>> mc = get_clip()
>>> mc
bpy.data.screens['Default.002']...SpaceClipEditor

The active clip of that space
>>> clip = mc.clip
>>> clip
bpy.data.movieclips['Batman_(1966)_S01E01.mkv']

>>> clip.tracking.tracks.data.settings.default_frames_limit
0

As expected, good taste when it comes to movies.

Here's a one-liner replacement for the get_clip function: mc = next((a for s in D.screens for a in s.areas if a.type == 'CLIP_EDITOR'), None). Not a fan of unreadable code like this, but sometimes you need a single statement (e.g. in drivers).


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Baked normal map freaking out. Normal node with it as input is Black
I did a retopo of my sculpt and now wanted to bake a normal map using Blenders bake feature.
I created a cage mesh by scaling the retopo up along its normals and then fixing some issues of overlapping topology in sculped mode. In the viewport is the result of a bake with these exact same settings, if I preview the normal map node everything is black. Only the Lowpoly and Cage meshes are UV unwrapped using smart uv project. Could anybody help me out here, I already tried backing with different combinations of Cage extrusions ( with the Cage option of) and Max Ray Distances but nothing seems to work. What am I missing?

Thanks for your help

hello, please share your file (with the high poly and the low poly): https://pasteall.org/blend/

Excuse me for using Google Drive but Blend-Exchange nor pasteall did due to the file size not work. https://drive.google.com/file/d/1Q55h3dp98P4wMM7hZIFLeXvc6R7_xZZ5/view?usp=sharing

that's weird it seems to work fine here: https://www.zupimages.net/up/21/40/zlwy.jpg ... have you selected the high poly, shift selected the low poly, then Bake?

also maybe try with another Blender version

shouldnt it be the other way around First electing the lowpoly and then shift selecting the highpoly, because wen I do it as you mentioned it complains about missing uvs

Or is it a problem with me using aces? I always set the color mode to Utility Raw

What version did you use

I've used the last version, I'm not sure about what you mean with the color mode, do you mean the Color Management setup? It should not change anything... For the selection order, you need to first select the high poly, then shift select the low poly

Yes, I am using the ACES colour management suit but disabling it did not seem to have helped. I tried it with the 3.0.0 Alpha but there it crashes.

Thanks for helping solved it see awnser

ok that's weird because I didn't change your settings...

Problem Solved by Backing in a new blend file, I suspect that I somehow messed up the render settings


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Compositing fire into footage with Davinci Resolve
I made a fire simulation in Blender. Then I rendered it as a png sequence with transparent background.
Now I want to composite this fire into some real footage (the camera movement is already matched).
But I can't find out how I can make the fire shine a glow onto my actor in the footage.
I am using Davinci Resolve, and have already tried the Light rays effect. But my problem is that I can only give it one colour and I can't use the fire footage as the colour source.
I know that this is the Blendr site but I could find a better place to ask my question. If it is unappropriated over here please point that out.

There is a designated blackmagic davinci forum, tried that?

Can’t be done with PNG! PNG is the worst, most poorly designed file format. Don’t use it.

Why PNGs don't work for this: Render semi-transparent volume with cycles with a great explanation by mr. brecht himself.

@troy_s On behalf of everyone, thank you for opening our eyes about PNGs :).

The more folks who understand the basics of pixel encodings, the better. In more specific terms for folks trying to do things with proper light transport concepts, PNG is an absolutely crippling encoding. This answer (https://blender.stackexchange.com/a/148466/213) from Robert G deserves infinite upvotes for more reasons to avoid PNG like the plague.

In case anyone is still looking for a solution, this video here has a compositing node tree that will fix this problem: https://www.youtube.com/watch?v=wNnFfXxB2Dg Just make sure to set the Set Alpha node to Replace Alpha instead of the default Apply Mask.

Why did you give up on using EXR (I have tried to import EXR files to Davinci Resolve with the LUT's) and go to a useless format like PNG?
PNG cannot handle associated alpha channel, it cannot have pixels that are emissive and transparent at the same time.
Go back to EXRs and be happy.
As for the glow on other elements you have two choices: Create some geometry in blender that will be affected by the fire and use it to add luminance to the scene in the compositor of your choice (fusion can do that) or even as a video track over the original footage in davinci. Or use masks on the footage and selective color correction and try to recreate the effect on other elements of the scene.
In the world of movie-making, such scenes are shot with the special effect in mind, usually having lights that flicker and simulate the color and brightness of the fire. You will find out that it is hard to replicate after the fact. The intensity, direction and movement of the shadows to make a convincing effect will require a lot of work if it was not done in the original plate.

Yes sorry I mixed it up I am going to use EXR in the final version. And okay I will try it with masks.


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Export vertex colors in .abc alembic
I am unable to export an alembic with vertex colours.
I have a cube with some vertex colours on it that I would like to export as an alembic but on reimport, in a different file, the colour attribute has disappeared. Am I missing something?

Thanks for helping out :)


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Can't select vertices of different meshes in edit mode
why can't i select two objects in edit mode?     I am trying to make a face from two different meshes but can't perform the action

Distinct objects can't share faces. If you're using blender versions before the (currently Beta) v.2.80 they can't even be edited simultaneously in Edit Mode.
If you need to make two meshes a single object, in order to be able to bridge vertices belonging to both of them, then in Object Mode select both and Join Meshes (CtrlJ). Then Edit the newly created joint object.

what about A select in edit mode...its not selecting all objects

When you are in edit mode you have only access to the object that was selected and active in the moment you entered edit mode. Or, in Blender 2.80, to the objects that were selected

so if you hit B (for box select) it will only select one mesh that was currently active when you enter edit mode?

also wireframe mode is only displaying the selected object and not displaying on the unselected

yes. Edit mode is for editing the vertices of selected meshes/curves. All the rest is ignored. Object mode deals with the others objects, as the name says. If you need to make faces that use vertices from different objects, just do as the answer says :)


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Blender 2.8 reference image disappeared
I am currently working on a 3D model and I was using a reference image to get the proportions right. Sine 2.8 doesnt have the background image feature I was using an empty object as image. After fixing up some non-manifold edges I just noticed my reference is not visible anymore even though it is still listed in the outliner.
Does someone know why that is and how to fix it?

Image empties are as overlays and you disabled them to display. Enable them back and your image will be displayed again:

Are you in local view? In that case / (or View > Local View > Toggle Local View) should bring everything back

Thanks for the quick reply. I tried toggling local view for all of the objects and the collections but the reference image does not come back.

Yeah, I didn't guess right what your problem was :)

Since I have found this topic while having that same issue with Blender 2.9, I want to add that I had to solve it by re-enabling Extras. Wich might be what L0Lock meant for 2.8. After re-enabling Extras, my reference images were present again.

Tried that solution, not working... Any workaround? Using 2.9 too...

In Blender 3.0 if you're Overlays are on and you're able to see it in render mode but not in wireframe mode then the issue may something in the Object Properties tab for the image.
Make sure Depth is set to Default. Also, make sure the Opacity is something other than zero. If you want to see it from a non-orthographic perspective there is a check box for that in this tab as well.


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Is there a way to exclude parts of mesh from curving when using curve modifier
Is there a way to make parts of a mesh thats bending according to a curve (curve modifier) rigid?

I don't think you can do that with only one pipe object, I guess you have to create 2 objects, a pipe segment and a joint piece, and use a different technique for each one to make them follow the curve: Follow Curve modifier and Dupliframes.
For the pipe:

Create your curve.
Check out its direction in Edit mode, if its bad press W > Switch Direction.
Put its origin at its beginning.
Create your pipe segment, put it at the same point as the curve origin.
Give your pipe an Array modifier so that it repeats.
Give your pipe a Curve modifier so that it follows the curve.

For the joint piece:

Create the object, put it at the same point as the curve origin.
Parent it to the curve with a ctrlP.
Select the curve. In the Properties panel > Data > enable Path Animation, choose the amount of duplications with the Frames value, enable Follow.
Select the joint object, go in the Properties panel > Object > Duplication, enable Frames and deactivate Speed.
If you ever want to make every copy an object, press shiftctrlA, to make each object unique, press U > Object and Data.

Sorry I didnt answer in so long. Your approach works thank you!

For me the elements dont follow the curve that nicely though

please explain what's the problem, maybe share your file: https://blend-exchange.giantcowfilms.com/

My issue is that the curves I am using are are at acute angles so the joint pieces are not following the pipe properly. I uploaded my file where I was testing your method.

so anyway it would not work with any method, I mean you can't ask for both pieces that follows and don't follow a curve, you need to choose, perhaps shift the joint position a bit so that it doesn't fall on a sharp angle

Yeah I think there is really no way around tweaking it manually. Thanks anyway for taking your time to help me.

Yes. Select those parts in edit mode.
Press Ctrl+i to invert selection. Everything else is selected.
Create a vertex group. Assign the selected vertices to the vertex group.
Exit edit mode.
In Object mode apply the curve deformer and select the vertex group. It will be applied only to the parts you previously selected.


text:
Mathematical functions for mesh in Blender 2.8 beta
Does somebody know if it is already possible in the beta 2.8 to use mathematical functions for the mesh? I could not find the Addon "Add Mesh: Extra Objects", which I uses in 2.79. Any other solution for this?

Addons should be updated to 2.8 version, it takes some time.

The addon is still there - you can find it in \scripts\addons\add_mesh_extra_objects within the Blender folder. However, it hasn't yet been updated to be compatible with Blender 2.8 and so is not shown in the list.
Within the __init__.py file within each addon is a section that defines the 'bl_info' that tells Blender about the addon :
bl_info = {
    "name": "Extra Objects",
    "author": "Multiple Authors",
    "version": (0, 3, 2),
    "blender": (2, 74, 5),
    "location": "View3D > Add > Mesh",
    "description": "Add extra mesh object types",
    "warning": "",
    "wiki_url": "https://wiki.blender.org/index.php/Extensions:2.6/"
                "Py/Scripts/Add_Mesh/Add_Extra",
    "category": "Add Mesh",
}

The version section tells Blender what versions this addon is compatible with - in this case 2.74.5. Normally an addon would be deemed to be compatible with anything greater than this version number but it appears that Blender 2.80 includes some changes that mean that only addons that are specifically targeted at 2.80 and later will be considered.
You can try to get an addon to be accepted by Blender by amending its __init__.py to change the version to (2,80,0) - and this will get it to be listed in the list of available addons - but it is likely to fail when you try and activate it.
For example, it appears that the bpy.utils.register_module(...) function has now been removed in preference to byp.utils.register_class(...) - so any addon that uses the older method will now need to be amended to use the new methods. This will require each addon writer to update his/her addon to make it compatible.


text:
How can I view and edit modifier properties in the viewport in Blender 2.8?
I've just recently started playing around with Blender 2.8 after years of modelling in different software packages. I've memorized the most used keyboard shortcuts and customized most of the stuff, so that I could work in a fullscreen mode in Blender all the time, but when I apply a modifier I always have to exit the full-screen mode and divert my attention to the properties panel on the right side of the screen which is really irritating and kinda takes me out of the super fast modelling flow.
So the question is, is it possible to view and edit your modifier properties in the viewport? I know that to apply modifiers you use  object.modifier_add command and I've hotkeyed it, but I really want to have the ability to edit applied modifiers without switching from the full-screen mode. Is it possible to make the modifier properties appear in the viewport without heavy coding? Maybe there's just a code line like object.modifier_add that will allow me to do it?

Given Blender 2.8 is still in beta and undergoing changes the following will assist with your request but will need to be modified both initially and after updates that may affect the layout of the modifiers or the file locations/names.
After copying the additional code described in the script; run the script and when in the 3d viewport you can search for the operator "Modifier Settings".
It should allow full access to the modifiers.
import bpy
from bpy.types import Panel

class BasicSettings(bpy.types.Operator, Panel):
    """
    The basic modifiers settings
    """
    bl_idname = "view3d.basic_settings"
    bl_label = "Modifier Settings"

    @classmethod
    def poll(cls, context):
        ob = context.object
        return ob and ob.type != 'GPENCIL'

    def execute(self, context):
        """
        Show settings as popup dialog.
        """
        return context.window_manager.invoke_popup(self)
    # copy ~ 1600 lines from your blender installation
    # (\2.80\scripts\startup\bl_ui\properties_data_modifier.py)
    # class DATA_PT_modifiers(ModifierButtonsPanel, Panel):
    # starting at the draw definition as shown below
    # ending at the end of the class
    # replacing the draw definition here

    def draw(self, context):
        layout = self.layout

        ob = context.object

        layout.operator_menu_enum("object.modifier_add", "type")

        for md in ob.modifiers:
            box = layout.template_modifier(md)
            if box:
                # match enum type to our functions, avoids a lookup table.
                getattr(self, md.type)(box, ob, md)

    # the mt.type enum is (ab)used for a lookup on function names
    # ...to avoid lengthy if statements
    # so each type must have a function here.

classes = (BasicSettings, )

def register():
    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)

if __name__ == "__main__":
    register()

Ratt, thank you so much for your answer and all the scripting work you've done! Although the script is not working as intended (you can't edit modifier properties in that popup window), using your explanations, I've managed to run another script that I've found available written by Vaughan Ling called Heavy poly config (it's available for free). Although he has many weird pie menus, I've managed to use his properties popup script and bind it to a hotkey, and it works like a magic now! I've copied the script into startup folder so that it would boot all the time I start working.

Did you replace the draw definition in the posted script with the code as mentioned in the comments? Pulls up the full controllable menu on version 2.80 (sub 35).

My bad! I've done what you told in the comments of the script and it works, thank you so much for your time and explanations, you're a great human being!

Hard ops modifier has this feature, called hops helper ctrl + ~:

The Speed Flow addon also has this feature:

https://www.youtube.com/watch?v=GoOZ-dn-si8
Unfortunately, it isn't updated for 2.8x yet. It takes some time to update addons for new version.

Thank you for your answer! Yeah, I am aware of those addons, they're really great! What I was thinking is just using standard in-box means of blender to do that, the way you can bind object.modifier_add command to a key. But you might be right, there might be no inbuilt into Blender code library solution for this task though...


text:
How do I change viewport alignment of newly created objects with a python command?
I'm making a custom pie menu with a pie editor addon and wanted to have some buttons with options that will let me change the default alignment of newly created objects from "world", "view" to "3d cursor" as I tend to change these options sometimes and don't want to open preferences window all the time I do. Can somebody tell me if there's a specific python command that will allow me to do that? I can't seem to find one.

Answer:
In Python, the command to set the alignment is  bpy.context.preferences.edit.object_align = 'VALUE' where VALUE can be one of WORLD, VIEW, or CURSOR.
This will affect any objects added after you've made the change.
Background:
The way to find such things in preferences is to enable Developer Extras in the Interface panel.  Then if you hover over the input field and right click you'll get a menu like this:

If you select Edit Source it will make the source for that part of the UI available as text object.  You can go to the text editor and view the code.  You may have to use the dropdown to select the right file.  Here's the code for that field:
        flow.prop(edit, "object_align", text="Align To")

You have to do some decoding to get the proper name.  First you start with the bpy.context.preferences prefix.  The first argument of the prop field tells you that the field is in the edit properties.  The second argument tells you the name of the field.  Putting it all together you get bpy.context.preferences.edit.object_align.
If, as in this case, you don't know what values to assign, you can use the Python console to figure them out.  Before each line in the below sample, I manually set the field to one of the three options.  So the output below is the value you should use if you want that option.
>>> bpy.context.preferences.edit.object_align
'WORLD'

>>> bpy.context.preferences.edit.object_align
'VIEW'

>>> bpy.context.preferences.edit.object_align
'CURSOR'

Bonus for reading this far:
Here's a very crude demonstration of a pie menu using this command:
import bpy
from bpy.types import Menu, Operator

class MY_MT_align(Menu):
    # bl_label is displayed at the center of the pie menu
    bl_label = 'Align Mode'
    bl_idname = 'MY_MT_Align'

    def draw(self, context):
        layout = self.layout
        pie = layout.menu_pie()
        pie.operator("my.align_world", icon = 'EVENT_A')
        pie.operator("my.align_view", icon = 'EVENT_B')
        pie.operator("my.align_cursor", icon = 'EVENT_C')

class MY_OT_align_world(Operator):
    bl_idname = 'my.align_world'
    bl_label = 'Align World'
    bl_description = "Set New object alignment to world"

    def execute(self, context):
        bpy.context.preferences.edit.object_align = "WORLD"
        return {'FINISHED'}

class MY_OT_align_view(Operator):
    bl_idname = 'my.align_view'
    bl_label = 'Align View'
    bl_description = "Set New object alignment to view"

    def execute(self, context):
        bpy.context.preferences.edit.object_align = "VIEW"
        return {'FINISHED'}

class MY_OT_align_cursor(Operator):
    bl_idname = 'my.align_cursor'
    bl_label = 'Align Cursor'
    bl_description = "Set New object alignment to 3D Cursor"

    def execute(self, context):
        bpy.context.preferences.edit.object_align = "CURSOR"
        return {'FINISHED'}

classes = [
    MY_OT_align_world,
    MY_OT_align_view,
    MY_OT_align_cursor,
    MY_MT_align,
]

def register():
    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)

if __name__ == '__main__':
    register()
    bpy.ops.wm.call_menu_pie(name = 'MY_MT_Align')

Thank you for your thorough answer, I am just starting to learn the API of blender after years of use. You saved me, I was looking for the method for quite a while and looked in the wrong direction. For some reason I thought it was somewhere in bpy.context.Preferences class, your answer cleared everything out for me and now the structure makes perfect sense! A new addition to my mega pie!

You're very welcome.  I'm glad I was able to help.  I look forward to seeing what you accomplish.  The Preferences settings take some getting used to, but now you've seen the organization you should have no trouble figuring out the rest of them.

I should add that the script at the end is using a big hammer.  You can do it with a single operator, if you give the operator a string property, set the string property differently in each operator entry in the menu and use it for the assignment.  But I wanted the crude version to not introduce too many concepts all at once.

Ooh, yeah. I figured that 3 operators for 3 methods with one command might be an overkill. Thank you for your help, you saved me lots of headache! :)

You can also directly modify the enum prop by adding pie.prop(context.preferences.edit, "object_align") to the pie draw method


text:
Mesh text individual letters change colors
Is it possible once you change a single text object to mesh, change each word a different colors within the key frames. I thought you could just select the word change the colors within the key frame. Unfortunately, this changes the entire text no matter which word I choose. Any help is appreciated. Using Blender 8.1

Speaking from Vers 2.77 here but 2.8+ should be the same or very similar...
Once you've changed your text to mesh you should be able to do that at least two ways -
1:
In edit mode select only those faces on the word(s) you wish to re-colour.
Assign them a new material slot and change it's colour.
2:
In edit mode, select the vertices in only the word(s) you wish to re-colour,
Part them from the mesh with "P".
Return to Object mode and select the words as a separate mesh and give it a new material slot if it hasn't got one already.  Colour it as required.
Parent the new mesh to the main text body if it's to be moved.
Colours can be changed with keyframes as with any other animation.

@Edgel3D
#2 worked.
I could get it to work by selecting each word then using "P" which takes each word and makes it a separate object. This is the same result if I were to type each word individually then put it together. There is a huge positive of the "P" method. Typing it all out at once, you now know each letter/word is exactly were you want it. No lining up different words to make it look like it's one sentence.

Glad it worked for you.  You're right.  I use the 'P' method to have certain words and even single letters to comically fall from signs and text.


text:
Color Scheme node?
I am designing a little something to be printed onto a T-Shirt.
But I haven't decided which color the shirt should have, which has direct impact onto the colors I want to print in.
Is it somehow possible to implement a Node where I can select between a few color schemes, eg. "Colors for white shirt", "Colors for red shirt" and so on, causing an "If selected first option, output red here and green here and..."
The thing I do not want is to have to fiddle with all the colors each time I change my mind about the shirt color.

Hello :). You could create different color variants as nodegroups, and switch between them inside one material :).

Hey :-) -- That would be necessary for every material, or am I misunderstanding?

Depends on how you implement it :). Related: Switch node in Cycles material?

Just found this, could that be feasible? https://animation-nodes.com/

I don't work with animation-nodes but there are many experts on this site :).

Just to illustrate a simple switch for two nodegroups.
This answer covers a more complex switch with multiple inputs.
Using nodegroups inside other nodegroups could affect multiple materials at once.

IMHO It would be easier to create a number of differently colored models :).


text:
Render is duplicating random frames when loaded into 3D tracker
I am trying to render an edited clip at 23.98 fps for use with motion tracking in a different project that shares the same frame rate. However, when I go to the tracker when the rendered clip is loaded, some of the frames show up twice in a row, thus throwing off the whole track. Any idea why this is happening?

Most likely the video is recorded using a LongGOP format and not an intraframe codec.
http://tiliam.com/Blog/2015/07/06/effective-use-long-gop-video-codecs/
What that means is that every frame does not contain the full information for the picture, but only records the changes from a reference (I) frame. Blender has a hard time dealing with that format.
Try exporting the video as an image sequence or a video format with intraframe encoding, so that every frame is available to blender for tracking.
Another common error is using video files recorded on some phones and screen recording software that encode using a variable frame rate. Blender cannot deal with such files correctly, they need to be converted to a stable frame rate (or an image sequence) in an external app, before importing into blender.

Ok thanks. I just decided to go with an Image Sequence.


text:
No active image when baking texture
I'm new to blender, so it could be something very simple, but I've been trying to get this texture to bake for two days now. I've watched a bunch of different tutorials and I keep running into different issues.
https://gyazo.com/eb7e89db3ce13c0805ecb87b07e5343c
https://gyazo.com/9a74ca5c29ffc35b9e6d6c5eb107389a
I unwrapped the well, added an image node in every material, selected the well texture in every section and changed the engine to Cycles to bake. It gets four done, then fails with the error message "no active image found, add a material or bake to an external image file"

I would suggest to attach  simplified blend file that still produce the error via https://blend-exchange.giantcowfilms.com/

How to upload an image to a post


text:
Creating shape keys of armature's preserve volume
Since preserve volume doesn't export out of blender, I was wondering if I could convert it into corrective shapes. Is there a way to isolate preserve volume's deformation after posing a bone and make a shape key out of it?

Enable Corrective Shape Keys addon
Set target pose or animation to the rig
Select model. Turn on Preserve Volume
Duplicate model
Select the copy. Delete all shape keys. Apply Armature modifier
Select first object. Turn off Preserve Volume. Create and select new shape key
Select second and first models. In Shape Key Specials select Add as corrective pose-shape
Done! Unpin Shape Key Lock. Now you have preserve volume's deformation in the shape key.


text:
How to uninstall blender
From the control panel, I click on Blender and right-click to uninstall.
Getting this pop-up

How to uninstall old version 2.79 complete blender version from pc.
Any suggestion or help. Im using win7.

It should be in the list under Control Panel > Programs and Features assuming it was installed in the conventional way unless the installation method was different for 2.79? Just click on the Blender entry in the list and then hit Uninstall from the menu. If it was installed as a portable version you can simply delete the folder it's in.

@JohnEason Yes i have deleted the folder but how to remove or uninstall it from the control panel list

We're getting off topic and away from Blender-related questions here but see this page for how to remove an entry from the list. Be very careful if you're not familiar with the Registry! A quick tip to find the correct entry among all the unintelligible entries is to hilight the main 'Uninstall' folder, press F3 and search for 'Blender' to find the right entry to delete.


text:
How to scale with proportion with N panel?
Pressing S to scale it goes in proportion but it shows in which measurement I don't know. With the N panel, it shows the dimension for example 10cm, How can I scale with proportion by inserting the value?
For example, I want to scale to a proportion of 10cm down or up to an exact value. How it will work, any suggestions or help? Thanks

in blender you dont scale by adding or removing a dimension, pressing S will allow you to create a multiplier, for example pressing S, then 2 will double the dimensions, if you go to the yellow button with a square in a shape it will give you the same contents as the n page, also you can type mathematical opperator for example after any value if you add *2 or +2 it will multiply the value by 2 or add 2, this works with many different operators

One way to scale in proportion to a given dimension in X,Y or Z:

Enter the desired dimension in the 'Dimensions' panel
Go up to the scale panel, CtrlC copy the scale from that axis
Swipe the 'Scale' fields, and CtrlV paste

.. followed by CtrlA > Apply Scale.
If you're working to, say, an edge-length, not a major dimension, find the existing length, using, say, the 'MeasureIt' shipped add-on, type "new_length / old_length" (substituted) into one of the scale fields, and copy-paste as above.


text:
How to distribute object in between?
How to distribute objects in between? without addon (not with array).
Video
or similar to Sketchup video
When duplicate and press / the value, the object is divided between 2 objects with the value and distributed, and if press * the value a multiplied and distributed.

Please don't just share a video that we have to watch or scrub through. Links can expire and render your post as unusable. Present all the information directly into this post, be detailed with screenshots of your issue.

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

Can you illustrate what you mean in the post, please? It's not clear what 'the value a multiplied and distributed' means.

This GN group will give you amount linear tweens from the modified object (left) to another with corresponding topology (right)...

If the target is identical to the source, that's a stretchable array ..

..if not, distributed shape keys.
The group assumes meshes with faces.
There are obvious possible elaborations; instances along a curve, automatic generation of the target, indexing better suited to  needs.. that would all depend on exactly what you want.


text:
How to make light similar to LUMION
How to make light similar to LUMION, Lumion uses only 1 HDRI image and not extra lights, why in blender do we need to add artificial extra lights? in exterior rendering? Anyway, to make a scene similar to Lumion just using HDRI image only and rendering in Cycles?

I'm not sure what you mean, you don't have to use lights if you don't want to, you can use an HDRI only

I'm sorry this is a site about using Blender, not everybody knows Lumion. So would you please show us the differences? I've lit exterior scenes with 1 HDRI, you don't need to add artificial lights - depends on what you're looking for (again: not everybody knows Lumion). It's just that some people add artificial lights to have specific control on how certain parts of a scene are lit instead of relying on one magic HDRI that perfectly matches their desired outcome.


text:
How to export in .stl with separate mesh
I want my model to be exported in .stl for 3d printing. When selecting all mesh and exporting as .stl it export but all mesh gets merged and 1 mesh is created. I want all my mesh to be separated after exporting. I tried to import the file and check, but it's a single mesh. How to export all the mesh separately in. stl format. Any suggestions or help? Thanks

While exporting, select the Batch Mode as Object, and then export, all the objects will be saved to separate files.

You should try to use proper terminology which Blender uses, otherwise it gets a bit confusing: one object can have separate meshes. If you choose Batch Mode > Object, those meshes will not be saved separately if they belong to the same object.

Well, it is quite simple: STL does not support multiple objects in a single file. If you want to have them separately, you have to export those parts individually.
But you don't have to create multiple Blender files for this, just select one object at a time and on export enable the Include > Selection Only option.
//EDIT: I don't know when this feature was implemented, maybe it's not even new - but you can use Batch Mode > Object to create separate files per object automatically. In combination with Selection Only you could for example only export 5 selected objects in a scene with 10 objects.

did not work same result, 1 mesh

Do you have separate objects in your scene? Did you select one? This Selection Only is for selected objects in Object Mode, not parts of an object selected in Edit Mode.

NO, I have selected all the mesh. I think i got the answer

@atek Yes, I was just editing my answer to add this batch option. Don't know when this was implemented, never used it before. Still, using Selection Only should have worked with a single object. With the terminology you use it is a bit unclear what you are saying: "selected all the mesh", are you now talking about Edit Mode or Object Mode? Because the mesh is usually what you are working on in Edit Mode and only there you have a choice to select all or just parts of the mesh. In Object Mode, selecting an object always selects all its mesh.

selected all the mesh, i mean without selecting all the mesh it will not work, if u do not select the mesh and try to export nothing will export.

@atek If you disable Selection Only, everything will be exported, not nothing. And still I can only ask you to use the terminology Blender uses to make clear what you are talking about. One object can have many separate mesh parts. But Batch Mode will not separate the meshes in a single object.


text:
How to fix uv with exact dimensions?
i have a wall 10x10 feet and with the regular way i have uv, smart uv, why need to scale up or down, is there any way or addon that fix the exact size or dimension on the face. why need to manually scale and assume the texture looks good, any other way.any way to make it fix or calculate the dimension and set.

Hi :). Yes, you want to keep Texel density the same. You can use addons like Magic UV (shipped with blender i believe)

@JachymMichal can i get detail comment or answer how it works

Hi :). There are many answers already on SE and YT videos explaining texel density. I don't have time right now ;)

@JachymMichal let me search and get you back, Thanks


text:
How to unbend some part of mesh?

I want to unbend some parts of the mesh. Below i have a Plastic model below the plastic model the is leather which has been bend on the pillow. The Plastic model and the leather are been pasted, so the pasted part will not bend on the pillow. (Note i have not attach or join plastic and leather mesh, due to distorted mesh going in the blend file attach). I tried to make verts group and assign, but for me it's not working, Any suggestions or help to fix the issue? Thanks

Just select those vertices and press S,Z,0,,Enter

unbend == flatten? Think from that perspective.


text:
Use volume float vector velocity field for motion blur in Vector pass
I simulated a pyro sim in houdini that generated three vector field (vel.x, vel.y, vel.z) and then merged them into one velocity field that I exported to a vdb.

I applied a basic shader to the volume and enabled the vector render pass:

But for some reason, the Vector Blur node in the compositor does only blur the cube and not the volume. Do I have to pass the velocity field to the renderer? Is there something that I have to do in the shader?

Thank you for your help.


text:
Automaticly merge multiple frames from a camera projection into one
I have tracked my camera and recreated the scene mesh on which I am projecting the frame of the image sequence.

If I step some frames back the camera "sees" something different. A different area is textured. How can I now automatically merge these different projections into one so I get a continuously textured model?

I found this tutorial of CGMatter explaining the process but for a scene where multiple textures are needed, this is quite a labour-intensive job.
Is there any way to automate or speed that process up?
I am aware of this StackExchange question but I do not really understand it and it's quite old too.
Thank you for your help appreciate it a lot. :)

I would suggest use shader for projection instead of modifier that generates distortions. Also merging several projections in shader sounds to me probably easier. BTW ... Next time plan a bit if possible and spend a minute to capture spherical 360 deg environment texture ... easy to reconstruct

Yea, I usually take a HDRI but this was a quick shot in the train station. but thanks for the shader idea did not think of that


text:
how to get 3 balls with physics to animated plane working
I have 3 balls "on" a plane, all with rigid bodies and active.
I have an animated plane with hook and tried both, passive and active, the balls are not reacting correctly to my animated plane.
are there restrictions i don't know or just another very dumb mistake of me?

Here is my blend file:


text:
how to change pivot point of extruded text to the edge of extrusion
Is it even possible to change the pivot point of an extruded text to the edge of extrusion?
I know how to change the pivot point, but i cannot set it to the edge of extrusion...

You mean an extruded text that is not converted to a mesh? Not as far as I know, since there is no real geometry to select and e.g. snap the 3D cursor to. So it would only be possible to try to put the cursor to the right place and set pivot point to 3D cursor, or set the cursor to some value where you know the XYZ position of the edge, for example you extrude it 1 m so you know the edge is at Z = 0.5 m or something like that.

yes, i mean and thought that...thank you


text:
Array with spot light as child possible?
Beginner question:
I have an object with a light as child.
I want to use the array modifier with the object and hoped, the lamp would be "arrayed" too but it isn't.
What am i doing wrong?

not really answer, but yeah, it is a workaround

It's not possible to use modifiers on lamp objects so no, but you can array a single vertex or a face and use that as an instancer like in the linked q&a


text:
cannot add driver for fcurve noise values
I am not able to add any driver to this noise-modifier values.
Ok, i can accept that it is that way. But until now nearly every value i could "drive" with drivers. Is there a special reason for this?
And is there some workaround possible?
Reason is: I want to copy an object with animation + noise modifier but each noise modifier should have different offset/strength values which i would like to randomize.

Marty Fouts (a wee bit grumpy, LOL) writes this.  I want this candy also!


text:
sverchok - how to "update all" via command line
Is it possible and if yes, how can i trigger "update all" from the command line?
I need this because if i render without update all, the animation won't animate correctly (the nodes which are connected to the frame aren't updated). When i press the button, it works. But i want to render from the command line.

Enable python tool tips in user preferences, and then see what method the button calls.

Thank you!! The really bad thing is: i knew it some time ago…♂sometimes I hate my memory! +1

You’re welcome :-) don’t forget you can renew your mind .


text:
orientation of particels in grid mode
Is it a bug or just logically and i don't understand it?
I have c cube with particles facing perfectly in normal direction. I am happy with that:

If i change the distribution from random to grid i got this:

is it a bug? or how can i get normal direction in "grid"-mode?

Maybe it's a limitation of the grid distribution? There is indeed a bug that makes the orientation and location (=an offset) of the instance object go wrong. You can fix the problem if you check and uncheck the Use Modifier Stack checkbox (even when there are no other modifiers). But this doesn't help with the grid distribution. If you want to create a spiky ball you can create an Ico Sphere, use Jittered, uncheck Random Order, and use 1 Particles/Face. Set the number of particles to the number of tris the sphere has.

Try returning to the first frame of the cache


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how can i align two objects and see them from each side with 1,3,7?
If i have a cube and a beziercircle, both rotated randomly.
How can I make the beziercircle exactly around the cube on his orientation?

wanted result:

And is there a way to see these 2 objects now from all sides as if they were flat on xy? as i can see things when pressing 1,3,7 ?
so i would like them to see them like this:

You can select your cube and in the Transform Orientations panel, click on the "+" to create a custom orientation:

Select the circle and Object > Transform > Align to Transform Orientation:

Also with some ShiftS put the 3D cursor at the cube location, select the circle and put it at the same location:

To see their front, side and top view press Shift1, Shift3 and Shift7:


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What causes the unexpected rotation of 3D models in between NLA tracks?
I am using blender 2.82a and can't figure out why my 3D model rotates unexpectedly between NLA tracks when Blend Out is used. I've checked the rotation values in the viewport but nothing changes when the model rotates. As you can see the image, the model is in a 45 degree angle, the model should be standing straight.

This is just a guess, since I'm still trying to get my head around the NLA. But it seems that the Hold, and Hold Forward features are very important when you're using multiple contributing strips, because, and I'm not entirely certain about this, but it SEEMS that the default behavior is for Blender to try and revert your rig to its default pose IF and WHEN it is at a point in the timeline for which no strips are currently influencing it. UNLESS you have the Hold options employed. Sorry if this misleads, but it's at least worth exploring. I hope to know more about how this works, eventually.


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How do I make a translucent/transparent material on eevee?
something like this
ive followed multiple tutorials but they all result in my objects looking shiny, any help?

show us your settings like material settings via screenshot. or provide your blend file.

Shiny as in not transparent and pseudo-reflective?

ive followed multiple tutorials but they all result in my objects looking shiny, any help?

So your question is actually how to make a material not shiny.
If you have looked up tutorials, you probably have found already so I will make it simple and pretend you use a principled shader from which you obtain the transparency effect by playing with its transmission and/or alpha settings.
The first obvious sources of any shininess in a material are the specular and metallic settings. They are the ones that make the surface reflect light, so turning them off if the first step.
The second source can be the transmission itself. As transmission is emulating physical light transmission, it refracts light, meaning the light rays going through are deflected at each environment change, which can make you see stuff in a "weird" way, as when looking through a glass or a filled cup of water.
You can tweak that by playing with the Roughness and Transmission Roughness, though if you want no refraction at all you should just turn Transmission off and use the Alpha only; thus making your material not following the laws of physics, but you need what you need anyway.


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i want to make a wave texture in surface?

i want to make something like this orange cube how can I make one?

you could use 3 materials, one for the bottom, one for the sides, one for the top, for the top use a wave texture and bend it a bit with a noise?


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Script for making every material one material per one object
I need some help with making a python script.
Anybody know how to automatically duplicate any material that's linked to multiple objects
so that there is one material for every object?
For example,

Here you see Material231 linked to two objects; Cone and Cube. I would like to develope a script which duplicates/makes a new material based on Material231 and automatically links it to other objects.
Any help is appreciated.
Thank you!

Thankfully it’s very easy. The material datatype has a method copy() which returns a new duplicate material.
Something like this:
for o in bpy.context.selected_objects:
    o.data.materials[0]=o.data.materials[0].copy()

This code assumes the material is linked to the mesh data block.

Object linked materials.
If you wish to have one material per object, suggest using object linked materials. Have explained this somewhat in https://blender.stackexchange.com/a/185428/15543
Albeit @ZargultheWizard's simple script will work in the question example case, where there are two distinct meshes the cube and the cone, if they were not then would end up with same material on each, that being the last copy, resulting in horrible names and unused originals.  To ensure each object has its own material will instead use object linked materials.
Running script below "should" result in all scene objects that have an active material, having their own object linked  material named after the object.
import bpy
from collections import defaultdict

context = bpy.context
scene = context.scene

mats = defaultdict(list)

for o in scene.objects:
    if not o.active_material:
        continue

    mats[o.active_material].append(o)
    # change to object linked material
    o.material_slots[o.active_material_index].link = 'OBJECT'

for m, obs in mats.items():
    # keep and rename the first
    o = obs.pop(0)
    m.name = o.name
    o.active_material = m
    # copy and rename the rest
    for o in obs:
        o.active_material = m.copy()
        o.active_material.name = o.name


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How can I stop materials from clipping?
I want to model a paper character in 3D. I started by importing the material of the character I want to create using an add-on called "Import images as planes". Then, I arranged the material the way I want it to be, however, when I take a look at the model again it ended up like the image below.

The material on the back seems about fine, however, the material on the front seems to be overlapped by the material on the back. How can I stop this from happening, and if possible, how can I prevent this in the future?

Please share your blend file.  I think you're saying that you have two images on two separate planes and you only want to view one from the back and the other from the front but I'm not sure?  Is that your question?

I'm trying to make a 2D character in a 3D space, I only added one plane, extruded it, kept one face on the front the same and relocate the material on the back to the back sprite. I made the sprite to contain both front sprite and back sprite, I used the "Import Images as Planes" add-on to add transparency to the character, I wanted the front and the back of the plane. to have different sprites respectively And here are the link to the .blend file and the sprite: http://www.filedropper.com/model (.blend) http://www.filedropper.com/acesprt (sprite)

First of all, you should prepare two images A and B such that A flipped horizontally has the same contour (the same alpha channel) as B. Otherwise, you will see that the character changes pose when flipping.
If you do that, then your problem will probably be solved: if you have a a very thin (0.001 m) cube with one big face depicting the front of an astronaut, and the other big face depicting the back of the astronaut, you won't be able to see the wrong side, as the right side will cover the other completely (because the alpha channels match).
Without doing the above, you can enable Backface culling to not display insides of an object:

Also, you don't need a cube and a single plane is enough - just use the Geometry > Backfacing to determine which side you're displaying:

Of course for a single plane, the Backface Culling has to be disabled.


text:
Moving an object by its vertices to another objects vertices
so I'm quite new to blender and may have missed something glaringly obvious. What I am trying to do is move a mesh to another mesh so it overlaps let's call them Mesh A and Mesh B. The meshes itself has quite a lot of vertices. I need these two meshes to align exactly so my thinking is to select one of the vertices of mesh A and move the whole mesh by that specific vertice onto another specific vertice on Mesh B. Here is where I am stuck. I cant seem to select individual verticies in Object mode and precisely guide it to another vertice. I tried Vertice snapping but it seems to only want to snap the "edge" vertice instead of the one i am trying to use. In Edit mode, moving verticies only move the vertice and not the whole object so thats not what i want either. I feel like its such a simple task esp as i'm used to other 3D modelling software like Rhino so this simple task not working makes me think i am missing something. I have attached some images below to try illustrate what i would like. Appreciate any advice and help on this! :)

EDIT: Ok so halfway through typing this i figured out you had to move the pivot point of the mesh to the vertice you want to use and go from there.... Quite a bit of effort just to move one vertice to another please tell me there is another method...

yes you can put the origin on the vertex you want on one of your objects, then put the 3D cursor on the same vertex on the other object, select the first object and Shift S > Selection to Cursor

(That's the Selection to Cursor with the 'Keep Offset' option)

as moonboots said, it can be easily done, but i am not sure whether his explanation is "enough" for beginners, so here the short story long:
Let's say you got a plane and a cone and you want to move one vertex of the plane to the top of the cone:

1.) select your plane

tab for edit mode

select your vertex

Shift - S -> Cursor to selected

Tab

Object -> Origin to cursor

select the cone

tab for edit mode

select your vertex

Shift S -> Cursor to selected

tab

select your plane

Shift - S -> Selection to cursor

result:


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Hiding node group input (compositor)

To compact my node (it will allow to add more adjustments) I would like to hide unused inputs. With dropdown list I could unhide chosen adjustment. That would be awesome if unhided adjustment will be added as a new field. Is it possible?
If not, is there any way to hide the group inputs with simple switch. For an example those 4 I have marked by red color will be hided in one field "adjustment" that will unfold when ticked.

Right-click on the node and select Toggle Hidden Node Sockets or press Ctrl H

Right- click on the node doesn't work in 2.82
CRTL-H is hiding all unused sockets. This is not what I'm trying to do.


text:
Unable to select individual parts of the mesh
I've been having issues when attempting to select parts of models. Due to the software I work in, I cannot export models as an entire part due to a poly limit. Whenever I attempt to select individual parts of the mesh, it selects the entire thing, rather than the body, headlights, etc, stuff I can pick out individually in Sketchup. I am importing into Blender .obj files and exporting in .obj files. I know I can go in and individually group faces, but that's a massive hassle for models that can be into the tens of thousands of faces.

One of the ways I can get around it is by selecting similar materials, but not all models I use have materials applied, so a solution is appreciated.

If your model consists of multiple meshes, you can

Select all other faces of the mesh using Select > Select Linked > Linked, Ctrl + L
Then separate the selected faces through Mesh > Separate > Selection, P
Or make each mesh into a separate object through Mesh > Separate > By Loose Parts, P


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Wrapping objects around a helmet
Currently I'm trying to model this military-style FAST helmet. I'm running into difficulties with wrapping this velcro around the side as well as this mount on the front (both circled), I've tried shrinkwrap for the velcro, but it doesn't seem to want to work with planes around the surface, and I'm unsure on how to go about modeling this mount on the front and making it flush with the helmet. Am I doing something wrong with the modifiers? How would I go about doing this?
(

I think you would be better off intersecting the helmet with the mount, and then Boolean-ing it to union them.

Duplicate some of the geometry from the helmet and then P > Separate by selection and you can just move it out a bit and hit it with a solidify modifier.

Thanks guys! I'll give these things a shot.


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Integrating CG imagery with footage from cameras using ACES
As a Corollary to this question (Using Blender with wider gamut than 709 primaries (like ACES)). How can I use blender to integrate CG, and footage from cinema cameras using ACEScg?
My goal would be to convert the footage to ACEScg in Resolve, generate and composite in blender and return to resolve without having to re-grade the images. Is that workflow doable?

As a loose outline, it’s much better to skip the ACES complexity and focus on what is required. ACES comes with its own entire set of issues, not the least of which is obfuscating the goals and the technical needs.
It’s All About Radiometric-Like Ratios
Integration requires using a specific encoding. That is, the key here is that we seek the radiometric ratios as they existed in the scene. This is perhaps the number one aspect of integration that is, and has been, overlooked for a long, long time amongst many folks.
The key here is to understand that cameras capture scene data. However, despite all cameras doing so, they all do not encode the data in a manner that is useful. Typically, camera encodings can be described in one of two manners:

Ready to view as an aesthetic, display ready encoding
Ready to decode and work with further

The Encodings
You’ll find countless examples online where people take random footage and attempt to integrate it. Some even can look pretty remarkable, such as some of Ian Hubert’s work.
The sad part is that this isn’t the appropriate means to make life easy for themselves. If the footage “looks ok” when played back, it likely is the absolutely wrong encoding to work with, and will result in no end of massaging, sucking up countless hours of time and energy, only to never-quite-look terrific.
This should be common knowledge now for anyone who has tried to take a generic JPEG photo found online and attempted to integrate it into a Filmic based scene; it just can’t be done well. Why? Because the display-ready image has become an impossible to decode combination lock on its way to becoming pretty to look at.
The Cameras
It might shock a majority of readers to learn that you don’t need an Arri Alexa LF to get these sorts of magical encodings. Sony, Nikon, Panasonic, Fuji, Canon, and other vendors now commonly include a log-like encoding scheme in their affordable consumer grade cameras. A good number of them offer the ever-more-useful-and-important on-board 10 bit or greater bit depth recording.
While countless YouTube videos wax lyrical with misinformation about “flat” picture styles and what they are good for, the value of the documented log encodings is entirely and completely missed; log-like encodings capture and encode scene reflectance!
That is, for every log-like encoding scheme such as Sony’s SLog1-2-3, Fuji’s F-Log, Panasonic’s V-Log, Nikon’s N-Log or Canon’s C-Log1-2-3, there is a documented function available in a PDF that describes how the values are encoded with a unique transfer function.
Unlike a display’s transfer function that encodes display linear light however, the gold is in the little detail that those normalized code values can be unlocked back to scene reflectivity!
Where sRGB’s transfer function can be undone to reveal the display linear light output from 0-100%, a log-like encoding can be taken back to the scene’s ratios from some low value to some high value.
Try It Right Now
To really hammer this point home, a simple and revealing test can be done:

Take any old generic render with a reasonable dynamic range to illustrate the point.
Save the image with a sixteen bit integer TIFF using Filmic Log Encoding Base. That’s the very flat, non-aesthetic looking one.
Assert that no looks are baked into the output. We want data, not aesthetics.
Using the Image Viewer, sample around the render using the Right Mouse Button. Note the values from some of the scene energy that appear on the left side of the information bar that appears. That is, the RGB values to the left of the CM values, not the right. They should extend up arbitrarily high.
Also save the exact same image using Filmic with Base Contrast to make it look OK. Save the exact same sixteen bit TIFF.

Once saved. Open up another instance of Blender.

Load the Filmic Log Encoding Base image.
Set the colour space on the image to the corresponding Filmic Log Encoding Base.
Set up a compositor node to assert the file is promoted to float and sample the values in the Image Viewer.
Add in one more input and load the aesthetic output Filmic with Base Contrast. In this instance, the image was encoded for an sRGB display, so the transform is sRGB.

Note the values? Despite the fact that the sixteen bit integer TIFF was encoded using a device referred 0-100% range in both cases, when properly transformed via an appropriate transfer function such as Filmic Log, the values magically are transformed right back into the scene referred domain. The aesthetic “looks good” Filmic with Base Contrast? Hrm... only 0.0 to 1.0 representing the display linear aesthetically warped light, not the scene.
And guess what? Those logs for all of those awesome cameras listed above? They’ll do exactly the same thing!
This allows one to take the log-like encoded footage and seamlessly integrate it into any CGI with nearly no effort whatsoever. Use them as reflections, as emissions, and have interactive lighting on all your work.
But Wait, There’s More
There is one little gotcha with the log-like encodings; they are almost always coupled with a unique set of primaries that are different from the BT.709 assumed lights in your sRGB display, and the default set of rendering lights in Blender for Cycles and Eevee. The details of the particular encoding are unfortunately often referenced as some sort of a “gamut”. That is:

F-Log will be also encoded with F-Gamut
C-Log 1-2-3 may be encoded with a few different gamuts
N-Log will be encoded with N-Gamut
V-Log / V-Log-L will be encoded with V-Gamut
S-Log 1-2-3 may be encoded with a few different gamuts

One must take care to, after linearization with the proper transfer function, to also take the primary lights to the same primaries in the rendering / working space. This is a slightly nuanced subject, and likely requires another answer unto itself once the camera specifics are known.
No Log Camera? No Problem!
Beyond all doubt, this is a mind blowing experiment for the intrepid 3D peep to muck with, and hugely encouraged for anyone who has a log-capable camera.
But what about all of us schmucks who don’t have the releativey more recent cameras with log encoding options? There is indeed hope with a little bit of effort.
It’s entirely possible to take generic camera footage and document the transfer function manually. It’s a little elbow work, but the results will be similar to a native log, and the output will be significantly better than ignoring the core issues. Thankfully, there is an absolutely amazing set of tutorials to achieve just this via Paul Chambers’ website. After having read that amazing series, there is another little hidden gem on his site to help you use that radiometric scene reflectance too!
The key point in all of this is never let some overhyped bit of a plug-in or system prevent one from learning the core principles. No amount of any canned system can help you here; it takes a bit of elbow grease and learning to unleash a heck of a lot of amazing work. You never know... there might even be a super top secret and visually stunning project being developed in dark crustacean labs. I wonder what would happen if someone asked them...

Thanks for the detailed answer, lots to digest there. To further clarify, I'm not dealing with jpegs or any imagery in or sRGB. I'm looking to use footage from Canon c300MK and Blackmagic cameras recorded in RAW (blackmagic does not provide any documentation on their color specs, but can be converted from resolve into any other colorspace).

I guess it makes a lot of sense to work in log encoding, but what color space? The only reason I was looking at aces was to work in a "common" color space, so that I could mix shots with cameras with very different color rendition and add some CG elements created in blender, all using Scene Referred values. Should I just aim for Rec2020 colorspace and log encoding then?

One of my concerns also being able to view the footage correctly while working in blender. My goal would be that the CG elements, once rendered and composited into the footage, don't look different. Roundtripping back to resolve without messing the color correction for the shots.

Correct that BM does not publish white papers, so you are saddled with using Resolve to decode to EXR, and the path is fraught with potential pitfalls. Canon does publish white papers, for example https://downloads.canon.com/nw/learn/white-papers/cinema-eos/white-paper-canon-log-gamma-curves.pdf. The issue with using wide gamut rendering spaces is gamut mapping; the results look like ass without it. ACES suffers this. Gamut mapping is tricky, however, and on smaller gamut devices, one can make a case that the result should be similar to rendering in the smaller gamut.

Are there benefits to rendering in wider gamuts? Absolutely. Without gamut mapping however, the results are simply unacceptable. Feel free to look at the garishly over saturated ACES examples out there for a good reason to stay away until more nuanced handling lands. Take all footage to the same rendering space and your concern about mixed sources largely goes away. It’s probably easier to break this open question into smaller sub questions as you work through it.

Final note, you are never working in a log encoding; the goal is to always work with radiometric ratios, or as close to radiometric-like ratios. The log encoding from the camera is simply that; a known encoding that permits decoding to that vital radiometric-like response.

It might take me a while to digest all of this, but I feel I have a grasp on it now to begin experimenting. I might be back with more questions later. @troy_s thanks again for taking the time to help. Much obliged


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Pose Mode - Clear Transform - All still creates jumbled skeleton
Using tutorial to give character a bone in its body:
https://www.youtube.com/watch?v=SBYb1YmaOMY
Following the guide:
Akward pose in Object Mode
(Which explains for to clear the transform very well.)
When I am following this guide, I get a Random Generated collection of bones being jumbled.
What am I doing wrong as I have followed the guide but it does not revert to the edit mode state in Pose?
See screenshot here.

EDIT - This is fixed if I remove my Inverse Kinematics, but i need them to move my character for the animation.

So following this tutorial below fixed my problem -
https://www.youtube.com/watch?v=S-2v_CKmVE8
its a double loop, and to fix it, I had to create a duplicate of the hand.


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Why does the simple deform modifier not bend when created or strechted on the Y axis?
When I create a simple cube and stretch (or create other cubes as one object) along the x or Z coordinate it and then add lots of loops cuts it seems to bend just fine. However, if I did all of this along the Y coordinate it messes up really bad.
Above I create a simple cube and stretched it along the X coordinate and add lots of loop cuts. I added the modifier and went to bend and it seems to bend fine.

Above I did the same thing however I did this along the Y coordinate and as you can see they both have very different results. I also selected X, Y, and Z-axis on the modifier itself still looks bad. I also tried adding an empty but the results still don't improve it. Is there a fix for this? or do I have to create everything on the X-axis? I am relatively new to Blender. Thanks.

There are two axes to take into account when using the Simple Deform modifier.

The axis of deformation, set in the modifier, around which, in 'Twist' and 'Bend', vertices rotate.
The axis of extent, which determines, according to the fraction of the object's bounding box along it, either side of the origin, how much the vertices are rotated.

The examples below have their 'Bend' deformation axes set to X, Y and Z:

as you can see, the axes of extent are Z,Z, and X.
I wish you could set both axes in the modifier. Personally, I always wind up using an Empty as an axis/origin object, and fiddle with it until it works.


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Not showing faces, edges, vertices and background ref images
I worked well with making this M4A1. I added a background reference image too. But because of a mistake of mine, now the vertices, edges, faces while in edit mode and background ref images can not be seen. i dont know how this happened but as I think this happened due to key in keyboard. But I dont know how to fix this.

please share blend file

Turn on overlays in the upper right area of the viewport.

You have Viewport Overlays turned off. (Icon with dot and overlapping circle top right of viewport.)


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Install torch in blender
I need to install torch in blender.
I've Blender 2.92.0 version installed in Ubuntu 20.04.
While trying to ensurepip I've the following issue:
(base) paolo@paoloIns:/snap/blender/111/2.92/python$ sudo ./bin/python3.7m -m ensurepip
Looking in links: /tmp/tmpf8idgzxo
Collecting setuptools
Collecting pip
Installing collected packages: setuptools, pip
ERROR: Could not install packages due to an EnvironmentError: [Errno 30] Read-only file system: '/snap/blender/111/2.92/python/lib/python3.7/site-packages/easy_install.py'

How can I solve this "Errno 30" ?

Are you running the console in administrator mode ?

Yes, I've used sudo before the command ./bin/python3.7m -m ensurepip

Try installing pip, ensurepip, and torch within blender's Text Editor. https://blender.stackexchange.com/a/283142/142292


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UV Editing - how to quickly select another object
I would like to quickly select another object and see its uv editing.
I know i can

change to object mode
select the other object
go to uv editing again
change to edit mode again

which are 4 clicks.
Is there any quicker way?

I thought Alt Q worked only in Sculpt mode, nice to see that it works in every modes   ^^

Try AltQ to switch from an object to the other (works since the latest versions). Also works in Texture Paint mode, Sculpt mode...

In complement to moonboots answer, the possibility to change object is also indicated in the outliner.
When in UV editing (or other modes), the edited object is indicated by a mesh symbol and other objects compatible with this mode are indicated by a dot.
You can change the object or add one, clicking or ctrl clicking on this icon:

All is in the documentation here.

+1 works also perfect, but moonboots was a bit quicker ;)

yes he was and his answer should be accepted (of course) Chris


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how to write text in the 3d viewport as statistics does?
Is it possible to "write" in the viewport as statistic does?

or this?

...and no, i don't wanna parent text objects to my camera.... ;)

an example here: https://blender.stackexchange.com/a/150314/19156

great! +1. thank you!

You can define a draw callback to do that and use blf module to draw the text you want.
Like for all callbacks, be sure to remove it when needed (add/remove should go in pairs so that you don't accumulate the drawings).
Here is a usage example with a modal operator (but you can also set it from a panel or others):
import bpy
# Blf is the blender module to draw fonts in the viewport
import blf

# A function to draw something (here mouse position)
def draw_callback_px(self, context):
    font_id = 0
    blf.position(font_id, 15, 100, 0)
    blf.size(font_id, 12, 72)
    blf.color(font_id, 1, 1, 1, 1)
    blf.draw(font_id, "Mouse position: " + str(self.mouse_pos) )

class ModalDrawOperator(bpy.types.Operator):
    """Draw a line with the mouse"""
    bl_idname = "view3d.modal_operator"
    bl_label = "Simple Modal View3D Operator"

    def modal(self, context, event):
        context.area.tag_redraw()

        if event.type == 'MOUSEMOVE':

            #Get the mouse position thanks to the event
            #So that it is update for the next time draw callback will be fired
            self.mouse_pos = event.mouse_region_x, event.mouse_region_y

        elif event.type in {'ESC'}:
            # When finished remove the callback from the callback list
            bpy.types.SpaceView3D.draw_handler_remove(self._handle, 'WINDOW')
            return {'CANCELLED'}

        return {'PASS_THROUGH'}

    def invoke(self, context, event):
        if context.area.type == 'VIEW_3D':
            args = (self, context)

            # Install the draw callback named 'draw_callback_px'
            self._handle = bpy.types.SpaceView3D.draw_handler_add(draw_callback_px, args, 'WINDOW', 'POST_PIXEL')

            self.mouse_pos = [0,0]

            context.window_manager.modal_handler_add(self)
            return {'RUNNING_MODAL'}
        else:
            self.report({'WARNING'}, "View3D not found, cannot run operator")
            return {'CANCELLED'}

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

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

if __name__ == "__main__":
    register()


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why does this geometry node tree not work if i make a nodegroup out of it?
This is a follow-up question to the great answer of quellenform here:
Texture map to a beveled curve or path
I only wanted to make a nodegroup out of it, then i created a plane, added a geometry nodes modifier like this:

and added the same curve + curve profile, but i got this:

why is it distorted? what am i missing? what am i making wrong?

Works for me fine (without distortions) ... https://imgur.com/3oQjr68

I can't check this at the moment unfortunately, but did you follow the notes? The whole thing only works in the Face Corners domain. You would have to pay attention to the Group Output(s).

@vklidu: thank you for checking that

@quellenform: of course i didn't follow the notes and obviously i cannot read ♀ sorry for that stupid question - that was the reason and thank you for your help!!

The node group you are using creates coordinates in UV space for the vertices of the faces (Face Corners) after the node Curve to mesh has created the mesh.
If you put this node tree into its own group, you would simply have to write the generated coordinates into the domain Face Corners for it to work properly.
The reason why Face Corners are used here instead of Points is because you are using closed curves (cyclic splines) as the profile for your mesh. Therefore the endpoint of the curve is always at the startpoint, which causes this strange distortion of the mapping where the points meet. On the other hand, if you recalculate the coordinates of the Face Corners, you get a homogeneous mapping even with a closed curve.
PS: If you don't want to begrudge me the RP, then please delete the question ...I just didn't want to leave a question unanswered here.