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How do you align objects along a vertex using geometry nodes
I'm using geometry nodes, trying to align my trees along a plane with beveled edge, however they are not standing perpendicular to the plane (or directly vertical as I want them), instead they laying parallel to the plane with a seeming random rotation along the x and y axes despite having no modifier changing the rotation of the trees.
Node tree configuration.
Thanks

But how do you really do anything "along a vertex"?.. :D

I assume that your tree has a rotation. Check this: Select tree and press Ctrl + A → Apply Rotation

Yep that did it - Thanks

Don't forget to mark the answer as correct


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Ways to align vertices on a bent cylinder
I have a cylinder that is bent into this shape

what are the ways in which the vertices can be aligned so that the cylinder would be straight again?
So far i've tried selecting each edge loop and then scaling them on an axis by 0 but it gets cumbersome if theres alot of edges
I have also tried switching to top down view and then snapping them to certain vertices so that it is aligned but this also becomes cumbersome with more vertices and edges
Whats a better way to do this?

if you bent this only on one axis you could try to select the centered one, enable proportional editing and the try to move it back by tweaking the radius and moving your mouse. But why can't you just add a new cylinder? or...if the cylinder might have modifiers and so on...delete all vertices in edit mode and add a new cylinder in edit mode?

If you don't need the intervening edge loops, you could box select all the vertices between the two end loops and delete them. Then select the top and bottom loops and use Edge > Bridge Edge Loops to reconnect them.

source: Stack Exchange

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

sort: votes


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How to render composition
I have rendered an image and am doing composition on it. Is it possible to apply the composition to the already render image without rerendering it completely? It would save me a lot of time.

Remove the Render Layers and the Composite node. Then use the Image node under Add > Input > Image and import the image of your render. Then do your compositing, and use the File Output node under Add > Output > File Output.
To output the file, use the Render Image button again. It should not re-render your scene.
Here is an example:

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


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I made a Node group in the Geometry nodes but it does not appear in the templates

I have the file saved in the asset library, but it does not appear whenever I try to add it in other projects

You need to access the node group from the asset browser, node templates are a different feature from an add-on

Look in the Group submenu, not the Templates submenu, I think that should work.

If you want to use your node groups as presets, you would have to save them in a separate file and use the "Node Presets" add-on. However, this is a bit buggy in the current version (v3.1) and you will need to modify it a bit.
You can find out exactly how to do this in the description in this post: How can I use custom node groups as node templates (Blender 3.1)?


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I am planning to use the noise texture to make the cylinders go up and down how can I achieve this?

this image is the current node system I made. If it is a mess I was just toying around

When the Geometry is still an instance, use the Translate Instances node.

Depending on what kind of motion you are going for, animate one of the axes of a noise texture. In my case, I will animate the W axis of a 4D noise texture.

Oh right! I forgot that another word for transform is translate. Thanks

@user15303824 Actually translation is just one kind of a transformation. While transformations can be translating, rotating, scaling etc. a translation is just translating, the shifting of a location. Sorry for being pedantic  ;)

no no, thanks for mentioning to me the meaning behind both and now I know. Thank you


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Geometry Nodes: is it possible to put a curve to connect in vertices of a grid or any other mesh? for a graph
I am trying to make a graph and I want to make it procedural in some way, I want to be able to put a curve connect in between different verts so when the graph gets bigger so does the curve

you can use this node setup:

result:

UPDATE:
you can always move "things" in GN with the transform node:

thanks for this but is there a way to make the curve to move?

please elaborate how the curve should move? you didn't write anything of this in your question. Of course it can move - just append a transform node at the end. But i guess you want something different? And if my answer helped you, please click on the checkmark left to my answer. thank you. If you have additional/other questions, please open a new question because you should only ask one question (these are the rules, i didn't make the rules...)

oh well I wanted to just know how to make the curve move on the x-axis so it looks like a radio or smt similar, but if I'm breaking the rules by asking twice then just ignore it

i updated my answer

I figured it out, thanks for helping me out I was going mad cheers

glad you made it. You are welcome.


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Geometry nodes connection between values

Hello, I don't understand why connecting the random value output and any of the grey inputs on the right doesn't match. What do I need to add? Thanks!

The round inputs/outputs is „kind of“ only one value, but the rhombus show that these are more values. That’s why you cannot connect them.

What do you want the random value for?  GN 3.0 doesn't really have a way to generate a single random float.

The way this seems to normally be done is to drive the Random Value's ID socket with an integer.  This changes the Value output socket to output a single value:

One of the not-well-documented features of 3.0 Geometry Nodes is that some nodes output type depends on their inputs.  In this case, an 'ordinary' ID would lead to a field output (the diamond shape) but forcing an int into the ID socket changes the output type to a single float value.


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How to join objects together for appending without messing up material settings
I need to append this eevee clay-like clock object I made into another blender project.

To do that easily I need to join all the objects together, but when I do, the clay material's scaling and preferences get messed up.

Is there any way to join it all into one object without messing up the material?

I don't know why this is happening, maybe others will have an idea, but have you tried moving all the objects into a collection without joining, and then appending that collection to another blend file?

pls provide blend file

Did you Apply all scales before joining?


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How can I make an object not drop a shadow in eevee but keep the shadows on itself?
I dont want this shadow to be cast, but I want the shadows to be kept that are on the mesh of the projector object. So the method of disabling the shadows in the materials settings won't work. Im looking for a similar option to the shadows off option in the ray tracing settings of cycles, but for eevee.

I have no idea if there is a good way to do this... I would do the following: create a duplicate scene, delete everything except for the projector and the scene lights. In the original scene duplicate the materials of the projector with Shadow Mode > None. Render both scenes, the second one with only the projector and lights with Film > Transparent. Then use Alpha Over in the Compositor to put the projector with shadows over the scene without shadows. If there were objects obstructing the projector, they need to be in the duplicate scene as well set to Holdout.

@GordonBrinkmann Don’t need separate scenes, just use layers. Otherwise, yeah: Use compositing for this one.

@TheLabCat Yeah sure, you're right. Something like that, I guess compositing is the only way in Eevee.

@TheLabCat ... of course it's dependent on the scene, but let's say I don't want to render the original layer with Film > Transparent, is there a way in the View Layers method to render one with background and the other transparent?

@GordonBrinkmann That is a good point. I have yet to find a solution to that. I am going to ask it as a question now.


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How to make an image texture with only transparency and no other Principled BDSF effects?
Fairly new to blender nodes. How can I keep the alpha part of a 2d image texture, without having a principled BDSF changing the lighting/brightness of the original image?
This is what I want, but without the brightness effects
This is the original, without alpha. I want the colors to look like this, straight from the original source, but with an alpha background.

The easiest way is to connect the image's Color to the Emission socket instead of the Base Color socket, then make sure the Base Color socket is pure black.

You want to connect it like this:

You can connect your image as an (unshaded) input into a mix shader, with a Transparent BSDF in the other slot. Use the image's alpha output as a mix factor.
Also, for best color accuracy, make sure your view transform is set to "standard" (instead of default "filmic").

This makes me wonder if the IAP_SHADELESS group node provided with Images As Planes is doing anything different than this. It currently contains 11 nodes, doing a bunch of Light Path calculations. If it is functionally identical, that's hilarious!

@Mentalist This is the same as using an emission node, which will glow (emit light onto nearby objects) in Cycles. The IAP_SHADELESS node is designed to prevent that.

@scurest I see, good to know! When setting up shadeless materials myself I usually just add a Light Path node and plug its Is Camera Ray output socket into an Emission node's Strength input socket. (Of course I also add a Mix Shader with a Transparent BSDF if there's an alpha channel.) Do you know if there's any case when using IAP_SHADELESS gives a noticeable advantage over the simple camera ray method?

@Mentalist That won't glow, but it will appears pure black when reflected in a mirror. IAP_SHADELESS will reflect properly. Judging by the names of the nodes in the group, it also does something for refractions and shadows, but I don't understand the whole thing.

@scurest Thank you for that important info regarding shadeless reflections!

Just plugin the image directly in the material output as you did in your last screenshot.
If this doesn't help, please provide blend file. Don't forget before upload to do File-> external data -> pack resources.


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How to setup reciprocating compressor rig?
Note: I put my object names in "".
I need to rig this reciprocating compressor such, that rotating the "Rotary Base" at its center, should pull the "Rotary Shaft" at the "Pivot" (which is a child of "Rotary Base"). I achieved this by applying a Copy Location object constraint on the Rotary Shaft and setting the target to "Pivot".

Now I need to lock the movement of the "Piston Shaft" on the X-axis, as it should go in and out of the "Cylinder". How can I somehow link the right-end of the "Rotary Shaft" to the left-end of the "Piston Shaft" while maintaining the "Rotary Shaft" movement with the "Rotary Base"(basically, the right-end of the "Rotary Shaft" should be locked on the X-axis while the left should be able to move.)?
I am open to other workflows (armatures included), so please.
The file I included, only has the models. The constraints and stuff I removed.

Does this tutorial help?

https://blender.stackexchange.com/questions/86804/rigging-an-umbrella-like-object


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Problem importing movie as plane
When I import a *.wmv movie using import image to plane in the 2d animation environment, it works correctly. When I attempt to do the same thing in the general workflow setup. the movie doesn't appear. I cant figure out what I'm doing wrong.

Are you able to see the movie when switching to "material- or rendered-preview"?

That did it. The new interface has me a little bit disoriented. Should have thought of that. Thanks, Quacksilber!


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Solidify faces as separate objects that touch
I have a mesh objects with faces. I would like to create separate objects for each face but solidify them at the same time while they still touch eachother. For a cube I could do this in the following way:

Create cube mesh
In edit mode, use Edge split (search 'Edge split')
Extrude E, but cancel immediately
Scale S (larger or smaller doesn't really matter)
Select all faces A and separate P > As loose parts

The result is something like this where each face is now a thick version of itself with bevelled edges that touch (one side removed to highlight the internals, but these are 6 separate objects).

However, due to the way in which scaling works, this does not work well for convex shapes. The scaling scales to the center of the object instead of along the normals.

I also tried extrude along normals, but this loses the shape due to the edge split. Somehow is does not exactly the same as scale and extrudes the exact shape of the face outwards (instead of keeping the edges together).
Which method could I use to achieve the desired effect for freeforms?

Are you looking for a solidify modifier followed by an edge split modifier (at 180 degrees)?

You can press ALT + s  to begin scaling along normals.

I tried this but it doesn't give the desired result after the edge split which I need to obtain the separate objects. After edge split, in the scaled version the edges don't stick together anymore.


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Blender and OCIO - Texture bug or what I do wrong?
my first question here is rather technical.
Because of my interest in color management and ACES I am writing articles on my website about this topic. For 3D related tests I am using Blender.
So I am working in Blender with the OCIO environment variable set.
I checked the following what is best seen on screenshots and would like to know what I do wrong or there is a bug.
I marked the important areas on the screenshots from the Blender Compositor (which seems to work fine) and the Shading/ImageViewer which seems to ignore a part of the colorspace transform or clamp values as long as the texture is not a EXR file.

Thanks


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Can't select bone while weight painting after parenting an object to a specific bone in the armature
I've tried parenting a backpack to a bone before and after parenting the rest of the character to  the armature with automatic weights. In both cases, this seams to turn off my ability to select a bone in weight painting mode with ctrl. lmb.I don't have Paint Mask or Vertex Select on, but I do use Vertex Select while weight painting usually. I'm in the latest build of Blender 4.02. I'd be ridiculously grateful for some help on this'n.

Woops! They changed the hotkey in Blender 4.x.  It's now Shift CtrlLMB. Never mind...

Shift LMB should work as well


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Layout tab showing a blank rectangle

the layout tab only shows a black rectangle.

This is normal if you only have that one texture. Once you create a new texture, or import an image, it will show up in that "black rectangle" and you will be able to use it. For reference: this box is not for shaders, it is for textures.

I had a model I made i switched over to the modeling tab and now it won't show up anymore.

You are in the UV editor workspace, Try switching to image editor ?

UV and Image editor are the same.


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How to concurrently layer a second set of image data over a 3d mesh?
I am concurrently recording RGB and thermal data and I would like to map the thermal data along with the RGB data on to the 3d mesh after the model is rendered. Any advice?


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Grease pencil hold frame/extend frame
I just started playing around with 2d frame by frame animation with Grease pencil. And it really has so much potential to be an amazing 2d animation software.
There is one huge thing that bothers me a lot, I have looked around for hours now trying to find an solution. But cant seem to find it. !
Basically I do my animations on 2s(a keyframe every 2 frames) So what I have done is that I have a bunch of frames for my animation. But I noticed that I didnt have enough frames. So I want to insert a frame(still on 2s) between 2 of the frames I already have. Now I can actually do this in Grease pencil, but the workflow it is so slow and tedious. First i have to insert frame inbetween, then move this frame and all frames after 1 frame forward, then I need to select all frames after the newly selected one and move them 1 frame more to get the timing right. Usually in my experience doing this kind of action should be simple one click thing, because you need to do that alot if you wanna add frammes . But in grease pencil this will take forever. Is there a way to do this smoothly?
So basically looking at the picture, I want to insert a frame where the marker is on the timeline, And it should be spaced just as the previous frames. And I want to do this preferably with a 1 or 2 click solution.

EDIT: Actually, writing this answer made me realise how convoluted it was, so today I learnt to write add-ons and wrote one that does the same thing in just one keypress. Get it here: Greaspencil Nudge Frames.

This is indeed a common option in 2D animation software that's lacking in Greasepencil, but it's still early days and I hope that E, for extend, will eventually do that (right now it just does a normal grab). Also note that Blender has always been more keyboard shortcut focused than other software, that tend to have icons for everything.
Here's a slightly faster way do this, but essentially the same as the other answer, starting exactly from your screenshot:

Press ] to select every keyframes after the cursor
G to grab
Move the mouse to the right by 2 frames (or press 2)
click to validate (or press Enter)

In your example you can set the timeline on the 9th keyframe, then hover the mouse over the right side of the dopesheet timeline and Ctrl click (select all keyframes from here to the end), then press G 2 enter. Now you're ready to draw your Inbetween.


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Animation keeps rendering same frames
When I got every setting in place for rendering the frames to images, I noticed that not that many changes were happening in between the frames. Here is frame 30, a rendering of smoke that looks exactly like the first frame rendered. When I switch the type of cache from Replay to Modular, the smoke does not show up on any of the rendered frames. If you have any suggestions for making the frames render how they should, please let me know.

Can you check the FPS. If it is not set to the default that might be a problem.

Yeah it's 24 fps right now.


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New water simulation for 2.8 not showing up
I wanted to do a water simulation in a cube, but for some reason the water particles only show up for a couple of frames before disappearing completely. If you have any suggestions, please let me know.

check the number of frames of the simulation on the DOMAIN properties. the default is 40 (so the simulations stops very early)

Okay so that works now, but after my newly set frame time, it disappears when it plays over the frames after that. How do I make the liquid stay and ripple?

add more simulation frames..


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Why is grass looking tilted?
I was trying to follow CGMatter's tutorial of how to make realistic grass (Create Grass Fast Blender Tutorial). So far so good, but now it looks like there is a wind blowing all of the grass to one side. Is there any way to fix this or do I have too many subdivisions? If you have any suggestions, please let me know.

You need to select the mesh used as particles/hairs and go into edit mode.
Rotate and move the object (in edit mode) till the emitter emits the mesh correctly.

Thank you so much! This solved the problem :)


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Is it possible to switch Transform Orientation from Global to Normal on the fly with just mousewheel?
I favor the mousewheel gesture to lock axes instead of pressing the axis letter on the keyboard. I'd like to know if you can do an equivalent to X,X or Z,Z to change the axis of an active transformation to Normal with just the mousewheel. I was sure I managed to do it at some point but I can't seem to find out how.

The Pie menus all have a quick-swipe gesture..(no button) is that how you did it?

No. That's on colon key or something, right? I was sure I just pressed a modifier + mousewheel click. I must be mistaken and probably remember wrong or something. Is it not possible to do the equivalent to X,X with just the mouse wheel? :(

Someone may come up with it.. it would be nice..


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Black UV editor
Im very new to blender, so im watching a begginer tutorial series on blender, but i ran into a problem, my UV editor is just a black screen and doesen't display the actual UV map of the object i have selected.
I imagine there is probably a really simple solution to this, but as i said im very new to blender, only starting to learn it yesterday so i dont know anything about nothing yet, any help is greatly apreciated.

The black area is most probably a texture, which covers the UV space from 0 to 1. Have you tried to zoom out in the UV editor? This can be for example done with the scroll wheel. And for the wire not displaying, when the mesh isn't uv mapped yet, then there is of course nothing to display. - EDIT, hmm, the image editor shows the NEW Button in the header. So there is no texture active here. Maybe you have a graphics card driver problem?

Another thought. The orange buttons tells me that this is not the default theme. Maybe the theme is broken? Could you please switch back to the default theme and have a look if things looks different then?

try this: move the mouse pointer to the UV editor on the left and press the 'A' key. If everything turns yellow/orange then your mesh is so dense that the outlines of the UV islands cover everything with black. Try to zoom out as suggested and you will see a black square.

People might be able to help you more if you provided a link to the file somewhere.


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Geometry nodes: How can I evenly distribute clusters of points on a cylinder
Goal:
I use the "distribute points on faces" node on faces that form a narrow cylinder (a "ring").
the points should create groups that resemble evenly distributed stripes across the ring (along the x axis).
Current solution:
Since the ring plane is parallel to the y axis i look at sin(y) of the rings position as constraint for the selection.
Problem:
This creates stripes but they get wider and wider towards the "sides" of the ring.
How do I formulate this logic so that the stripes width is constant?

Instead of using distribute points on faces, you can use mesh to points node. That way you can convert each face to a point and instance the stripes on them. Capture the normals first so you can rotate the instances accordingly

I prefer your solution because its ultimately easier to create faces in the shape i need first and then put points on them. directly controlling the point distribution is difficult and vague. In the end i got some nice striped forests on my spacestation: https://imgur.com/a/hbo8f14

tbh this is more a mathematical than a geometry nodes question...but anyway.
The trick is here to use the angle, so that you can get an even distribution:

Im sorry i couldnt reproduce your result at all in Blender 4.0.1 https://imgur.com/a/34XWrNb

then pls use exactly (!) my node tree ...and not something different. thx. and of course it depends on what the size of the cylinder is.


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Geometry nodes: How do I boolean-union N overlapping instanced objects?
I used geometry nodes to point-instance object A to object B.
The resulting instances of A now overlap, which is intended.
For further work it would be nice if the resulting mesh is a clean union instead of an overlapping mess.
In the geometry nodes all the instances of A are represented by 1 line so i dont know how to use a mesh boolean node in there.
And when converting object B to a mesh to apply the geometry nodes the resulting mesh still consists of unconnected instances of A. How do i create a union of the A meshes either during the geometry nodes or after?

If you use the Mesh Boolean node and only plug a single Geometry into it, no matter which Boolean operation you choose (Difference, Intersect or Union), this mesh will be merged together as if you used a Union operation on the separate parts of it, as you can see in Wireframe view.
Before using a Mesh Boolean:

After using a Mesh Boolean:

I used a Bevel modifier afterwards to show the result more clearly, you can see the new edges where the cubes are merged get beveled as well:


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Geometry Nodes: How to check distance along specific axis (with geometry proximity node)?
I instanced spheres on faces with a green material.
I would like to delete the spheres that protrude out of these areas (the ones on the border to the grey areas basically).
My nodetree uses geometry proximity to delete spheres as soon as they contain a face with a certain distance to the green stripes. But this checks for distance in all directions effectively deleting spheres sorted by their size which i dont want... instead how can i restrict the distance check to be only in the x direction?
I tried position node->seperate xyz->only x->combine xyz->source position (geometry proximity node), but that didnt do anything so i dont know where else to input that axis information.

Picture 1: The maximum amount of spheres.

Picture 2: I want to delete the spheres that protrude into the grey areas. But since the distance to the green areas is checked in all directions it also deletes all the big spheres. I just want my forest to be contained in the green area^^

The position must be restricted to X axis not only for the source, but also for the target. That's why your attempt affecting only the source does nothing.

(Using Blender 3.6.8)
Instead of relying on the distance in (X,Y,Z) space, only the projection along X of the vector connecting the actual face centre (Position node) to the nearest face centre (Position socket of the Geometry Proximity node) is compared by the Less Than node to the user defined threshold. This distance is computed by the four nodes outside of the frame delete trees based on distance to identify the modification.

Resources:


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4.2 Subsurface Scattering Random Walk (Skin) Problem
Does anyone know what is causing these edges in Blender 4.2 Cycles? Object is shaded smooth. Has something to do with the Random Walk (skin) version of SSS. Random Walk also has these edges. Christensen-Burley does not, but the SSS doesn't look as realistic as (skin). This is particularly problematic around tight angles.
I ran into this in earlier versions of Blender and was able to figure out a solution, but I can't seem to figure this out in 4.2.


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How Can I Control Emission Strength from a Light's Power Using a Driver
I'm trying to set up a material's "Emission Strength" so that it is controlled by an area light's "Power" value (for example, adjust the light's power, and the emission strength adjusts likewise) I'm experimenting with a "Single Property" driver type.
Does anyone know if this can be done with drivers? If so, what should the set-up look like?
Thank you.

Right-click on source, "Copy as New Driver", then Right-click on target, "Paste Driver".
You can additionally edit the driver to switch to a scripted expression if you want to adjust the ratio or use a more advanced formula.

I figured it out. Change Prop ID: to "Light", choose the controller light, then copy the data path of the light's "Power" to the driver's "Path:"


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skin textures not rendering from a premade image
So, disclaimer, I'm about six hours in to learning Blender. I've gotten to a point where I can mostly create and render a rough scene in a way that will work for me (I'm using Blender for perspective references to then use in photoshop).
Problem is that I got an image from CGtrader and I can't get it to render right. It's this image
Downloaded it, extracted it, opened the .blend and I can't find any way to get the skin to display correctly. It either renders all in black in Eevee and Cycles (clothing renders correctly) or in greyscale in workbench.
 cycles
 eevee
 screenshot of when I open the .blend
Any suggestions? I feel like there's something very obvious I'm missing but I can't find a solution anywhere. Thanks a bunch!!
ps. I'm using Linux Mint if that makes a difference

A screenshot of the skin material in the Shader Editor would be interesting to see how the material is setup... and the UV Editor to see how the UV map looks. When I look at the model site, I see it's a native Blender model - so I would expect it to be correct right from the start. Usually those problems are more common when objects are non-native file formats... hard to tell without the file what the problem is.

Or maybe it's a graphic card / driver issue like in this question: AMD GPU Material is entirely gray but the resulting error looks different than yours...


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Animation Nodes - convert letters to curve
How can I convert each letter to separate curve object with the Animation Nodes?
I'm  using Decompose Text, not Split Text - (I need Whitespaces on). My AN is 2.2.2 with Blender 2.93.5

you can use this node setup:

result:

The object instancer is a "object factory" which creates (instances) objects. So here i take the text length to create as many instances/objects of my "original" beziercurve as letters in the word are.

Thanks, Chris, that's an interesting solution. As I can see, formatting will be copied from source text. One question - there's some Bezier Curve in the Object Instancer - whai is this for and how it was selected? I'm a noob AN, so some explaining would be welcome.

if my answer helped you, please click on the checkmark left of my answer. Thank you. I updated my answer.


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Rigify grabbing geometry like it's a leopard print
I created a model, followed tutorials on how to set the meta rig, got it parented to the geometry with auto-weight, go to move a finger to test and the model turns into a porcupine. I look under weight painting and it does this. I've wiped out a few vertex groups and repainted, but it keeps resetting to be scattered across the whole body rather than isolated to the geometry I want the bone to move. I can't find why its doing this, I don't even know what to call it to search for a solution. In the attached picture, the vertex group selected is the left breast after repainting to 0 and then painting where I wanted it. I went back into object mode, returned to weight painting and it had automatically rescattered itself across the body. IDKWTF I'm doing wrong here but this is NOT logical behavior from the software. There is NO reason it should be doing this

Can you share the file?

Gonna take 8+hours before I can. Left for work

The only thing I can think of is that the rig is grabbing geometry it THINKS is in that location, but the geometry isn't really in that location. idk how Blender would mistake where an object is in the scene but still display it properly. I'm hoping someone has potentially seen this error before

It will also probably help to mention the model was created by using boolean modifiers to take geometry from other models and combine them together. I don't believe that should matter, but you never know

Did you apply all of the Booleans before parenting?  If so, it might be this: The automatic weight algorithm needs what is known as a "water tight" or "manifold" mesh model.  It looks like you've somehow managed to model your way into a model that has two or more such mesh models intertwined.  To tell if this is so, take the model in edit mode, deselect everything, hover over a vertex and type L.  It should select every vertex in the model.  If it doesn't that's your problem.

Unfortunately, the whole model was selected in that method. It seems it's watertight. I've even gone so far as to start over from scratch and try it again to see if I was still getting incorrect automatic weighting (before posting here) and that didn't solve the issue either. This has been a 2 day head scratcher and definitely one that makes me want to give up on all computers and go live with the Amish

Sharing a file would be great. But it looks like a messy mesh.
Try this: In edit mode select all geometry and

click Mesh menu > Merge > Merge by distance
press Shift+N (recalculate normals)

Then try to parent with automatic weights again.
I'll edit my answer if you share a file.


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Creating multiple curves from CSV
I have a CSV file that contains XYZ points for many separate curves. It is formatted like this

 x  y  z  curve ID
 1  2  3  aB12
 7  8  9  aB13
 8  10  40  aB12
 1  3  6  aB13

 I'm looking for a way to import these points and form them into individual curves based on their curve id. I have over 200 curves, so importing them individually would be quite time consuming.

This is probably quite doable but will likely require a script using the Blender Python API. Certainly you are not expecting anyone here to write it for you.

Related https://blender.stackexchange.com/questions/71458/how-to-read-a-csv-file-and-use-the-values-as-x-and-y-points-in-blender/71466#71466 and https://blender.stackexchange.com/questions/28690/how-to-import-recorded-iphone-gyro-data-into-blender/28796#28796 or https://blender.stackexchange.com/questions/35945/python-script-to-read-in-csv-file-containing-quaternion-coordinates-and-turn-it and many many more

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


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How do I smooth hexagonal shapes more into cylinders?

NOTE: I'm new to Blender/3D modeling, and this is my first project.
Here is a mesh of a clone trooper from a game from 2005 that I'm trying to "modernize." This hexagonal prism on his back is supposed to be more of a cylinder, but due to it's low-poly nature, it's obviously not. I've tried subdividing and smoothing the rectangular faces, but it bows the cylinder out in the middle as well as messing up the 90 degree angles between the rectangular faces and the hexagonal faces (possibly in an attempt to smooth those angles? which I don't want).
What's the best way to achieve a more cylindrical shape without having to manually bisect each face and translate the sides diagonally to make it more round? (If this is the only way, how can I perfectly translate the sides on the X and Z-axis EQUALLY so that I don't have to eyeball it?)

In edit mode, use Ctrl-R to add loop cuts to the sides of the 6 sided cylinder. Once you have an even division, select the vertices of the cap or end hexagon. Using Loop Tools addon, choose LoopTools> Circle, and the new vertices will form a circle. Repeat for the other hexagon.
edit:
Here is how I would approach it.
1. Original 2. Tris to quads 3. Delete the vert in center of the hexagon 4. ctrl-R loop cut the faces 5. LoopTools Circle to get the round 6. Extrude and carefully fill with quads

That didn't work because the rectangular faces on the cylinder are divided diagonally (essentially 2 triangles forming the rectangles), so it won't let me loop around it. :/ At least I think that's the problem. Is there any way to get rid of the divider lines so that I just have rectangular faces rather than 2 triangles that form a rectangle?

Alt-J Tris to Quads will help for the long faces, but if the hexagons are triangle fan then you might want to just delete the faces there until you get the division worked out.

Please see the edit to my answer with the pic of the stages

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


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How to refresh workspace
I do these operations in a for loop:

Selecting all objects
Remove
Add a mhx2 model
Add cameras and lamps
Bind cameras to model
Load a bvh file
Render

The problem is how to refresh the entire scene for next iteration? I have tried to load a fresh file using bpy.ops.wm.open_mainfile, but it causes an error. It seems that the entire project including the script loads again. So, I tried to remove objects in bpy.data.objects but I noted that there are bpy.data.cameras and bpy.data.lamps which should be also removed. What is the correct way to do this job? Does selecting all objects and deleting them makes the trick? Note that there is an animation along with cameras, lamps, etc.

The solution is to delete data collections. There are plenty of collections in bpy.data which are not cleaned after deleting the object. For example if you add a camera, an entry in bpy.data.camera would be added but after deleting the camera object that entry remains that finally leads to out of memory errors. So the solution would be some thing like this:
def clear_collection(collection):
    for item in collection:
        collection.remove(item, True)

def cleanup():
    clear_collection(bpy.data.actions)
    clear_collection(bpy.data.armatures)
    clear_collection(bpy.data.brushes)
    clear_collection(bpy.data.cameras)
    clear_collection(bpy.data.groups)
    clear_collection(bpy.data.images)
    clear_collection(bpy.data.lamps)
    clear_collection(bpy.data.materials)
    clear_collection(bpy.data.meshes)
    clear_collection(bpy.data.objects)
    clear_collection(bpy.data.textures)

cleanup()


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Constraint camera to move with object's bone
I have a person and a camera which is looking directly at him from side view. My question is how to set a constraint to move camera with spine bone? The camera should not rotate with bone, just move with the person to keep the side view. I have tried to set camera as the spine's parent but it rotates along. Also, I used child of, transformation, track,... constraints but can't figure out the right way. Another issue is that after setting the parent relation location of camera changes. Any help or suggestions is appreciated.

add an empty in, line it up with your spine, constraint it to the spine with "copy location"; 2. parent your camera to the empty; //now your camera will follow the empty/spine without picking its rotation data.

thank you. It works but after loading the bvh file for walking, the angle of camera changes. In other words, the camera view is not side view.

The cause of this problem is that loading bvh changes the rotation value of person and when I include rotation constraint it works well, except that the spine rotation also rotates the camera! Is there any way to overcome this problem?

add a bone specifically for this camera, make it copy your spine location, that way when you load the bvh file, world location of this bone stays the same. Then you use this special bone for what you were trying to do. I don't know loading bvh will change any bones' rotation but I hope this may help. The key concept is always add a lot of in between things to help delivering the value across.

A ChildOf constraint allows you to parent an object to another with the ability to turn off some of the transformations that are copied.
To have the camera move with the character and allow the head/shoulders to rotate within the camera view, you turn off the rotation options in the constraint. You just need to pick a bone that you want to follow, maybe the shoulders or hips depending on how much of the character you want to move in front of the camera.
When you first choose the bone, the camera may jump out of place, click the Set Inverse button to fix this. You can also move the camera into position after you add the child of constraint

Here the camera has a ChidOf constrained set to the selected bone, you can see it follows the bottom point of the bone but doesn't rotate with it.


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Make camera to move with animated object by makewalk
I have imported a mhx2 model and set a camera. Also the model is set as camera's parent to always look from same angle and distance. The problem is when the object is animated using Makewalk, the camera doesn't move with the object. Any help or guidelines is appreciated.

Have you tried using constraints?

This problem is because armatures do not move objects, they move the vertices within the object. Think of objects like containers for their data. So your camera is behaving properly, because your object is not moving!
What you need is to attach the camera to a bone in the armature, not the object itself. Usually the Root bone is used for this, but it will vary. Look at your armature and pick a bone that is moving with the animation. As you are using mocap data, it may not be moving the root bone. If not, you could use one of the spine, hip, or pelvis bones. The key is to use one that isn't rotating, as that will rotate the camera.
To parent to a bone, select your object, then shift+select the bone and hit ctrl+P. (The armature needs to be in pose mode.) Alternatively, in the Object tab of the Properties Panel there is a Parent drop down menu that can be set to Bone, and then lets you pick the specific bone.
It is also possible to use constraints to attach the camera. This is more setup, but can let you do things like only copy a bone's translation, and not rotation.


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How to import mhx2 model programmatically?
I want to import a mhx2 model into blender using a script. I know that the function is bpy.ops.import_scene.makehuman_mhx2() but cannot figure out what the parameters are. Could someone provide an example? Any help or suggestions is appreciated.

Here is an example:
bpy.ops.import_scene.makehuman_mhx2(filter_glob="*.mhx2", filepath="C:\\1.mhx2", useHelpers=False, useOffset=True, useOverride=False, useCustomShapes=True, useFaceShapes=False, useFaceShapeDrivers=False, useFaceRigDrivers=True, useFacePanel=False, useRig=True, finalizeRigify=True, useRotationLimits=True, useDeflector=False, useHairDynamics=False, useHairOnProxy=False, useConservativeMasks=True, useSubsurf=False, subsurfLevels=0, subsurfRenderLevels=1, useMasks='MODIFIER', useHumanType='BOTH', mergeBodyParts=False, mergeToProxy=False, mergeMaxType='BODY', rigType='EXPORTED', genitalia='NONE', usePenisRig=False, hairType='NONE', hairColor=(0.15, 0.03, 0.005, 1))


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Geometry Nodes: How to scale edges along the normals of (unrelated) faces of the same mesh?
I instanced a profile on a curve. Then i selected certain faces and made them red.
I want to move a set of edges along the normals of the red faces.
Using sample index to extract the normals of the red faces does not work for some reason (changing the scale of the vector math (scale) node has no effect). Why?

Solution: Use corners of vertixes node + face of corner node to obtain the index of the faces with the relevant normals. Play around with sort index to get proper normals. no material index node needed.
Thanks @Crantisz

Set position node moves vertices, so normals are coming from vertices. To get normal from face, you should transfer from vertex domain to face domain.
To do this, you have to use topology nodes, that can get face of vertex thought corner:

since you have used materials there is a more elegant way to sort corners by material index

There seems to be a misunderstanding, your solution moves the red faces, i just want to move the top edges marked by the blue line in the picture along the normals of the red faces. @Crantisz

can you elaborate what the "material index - 0" is for? I tried other numbers, even ones exceeding the number of materials and it seems to work as long as it is "substract". weird


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Geometry Nodes (4.1): How to make "hills" connect smoothly to flat terrain
My nodetree creates random hilly terrain on faces with the green material. Hills close to the border of the material get cut off. How can i force the hills to connect smoothly to the border instead of ending "in the air"?

you can use this node tree here:

to get this:
https://github.com/luckychris/blender_gifs/blob/main/flat%20at%20edges.gif
sorry for the gif-link, but since the "improvement" of the pic upload of SE, gif uploading doesn't work at all for me in the last days.
Essentially first i save the old position (flat), then i separate the border by using the face count == 3 (this works because you have nice quad faces, this won't work with tris or bad geometry), and then using the proximity to that border for mixing the factor of the old and the new position. The map range is for fine-tuning the result. Of course you can also use additionally or instead a float curve for even more detail fine tuning.

Thats almost perfect. Using "Edge Neighours = 1" is more intuitive to select the border of areas though, no worries about bad geometry like that. (gotta switch seperate geometry and geometry proximity to "edges" mode then)

that's actually a great idea!


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Glass material "muddens" material below it in cycles
I'm trying to do a render of a wristwatch, I'm not sure what happened, but somewhere along the line when I'm texturing the model, especially the dial part, the problem starts showing up.
This is the issue in question:

As you can see, the dial looks muddy, blurry, and it only happens when the glass is active on top of it. Now, this is the one without the glass:

Without the glass, it looks crisp, I tried changing light positions, problem still persists, it only shows up when the glass is on top of it.
This is the nodes I use for my glass material:

Is there anything I can do to fix this? Before it happens, I'm using anisotropic shader with radial tangent for the "sunburst" effect, but the glass makes the whole dial muddy, I read some solution in this site that the denoise kinda messes up anisotropic, so I changed the whole dial to use texture instead, but the problem still persists.
Another info:
Denoise on, samples 128
My laptop specs are quite old, it's i7 3630QM, 16gb ram, GT650M 2GB (it's ancient). Is this actually simple to solve, or my laptop just not capable for the fix?
Thank you!

Are you using denoising? Denoising usually doesn't work as well for refractive materials such as glass.

This is most likely denoising artifacts. Try increasing the number of samples

It's the denoising. The denoising is quite good, but especially glass materials produce a lot of noise, so with a very low sample rate like 128 the denoising artifacts become much more visible. By the way, is there a good reason why you use this material setup with 6 nodes to create glass instead of simply taking 1 Glass BSDF node? Or maybe a Principled BSDF set to Transmission = 1?

I see, so the denoise is the one producing this, thank you everyone, I'll try to increase number of samples, or just render them separately if possible...
@GordonBrinkmann I'm copying some tutorials for glass, the method you write looks better, I'll try it, thank you!

I agree - use a simple Glass BSDF and maybe bring the IOR down closer to 1 (but not exactly 1 - exactly 1 is zero refraction. )


text:
2.79 Projects are textureless in blender 3.4
im trying to use some room from a compilatory of old game files, the thing is, when i load it into blender 3.4, it shows like this:

but, when opening the file in blender 2.79, it shows normally

is there like a way to pack the textures or something? or maybe even a tutorial?
(PD: sorry if my english's bad, my native language)

Hi. You should provide all the relevant details about your problem if you wish to get meaningful help with it.

The magenta color indicates textures not found.. how were they stored in, or with, the 'old game files' ? What kind of files are those?

the .blend files are the "old game files" , but they only seem to work correctly on blender version 2.79

If the materials are made with the Blender Render or Blender Game engines, they won't be converted to EEVEE/Cycles and are discarded on opening, only the basic stuff is preserved like Diffuse Color. You need to recreate them in the 2.80+ node system.
You can convert materials from Internal to Cycles inside 2.79- manually or with scripts like https://blenderartists.org/t/materials-specials-conversion/664036 and then you can open it with 2.80+.
I had worked on a script that uses https://projects.blender.org/blender/blender-asset-tracer to do that without 2.79 but did not finish.


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origin not moving with pmx model when playing animation
I import the model using mmdtools. I want to create a child parent relationship between a group of lights and the model so there's no weird shadows. It works perfectly fine in object mode however when I start playing the animation the origin does not follow the mesh or the bones, therefore the lights are also not moved. I tried set origin to 3d cursor but failed. And all other option in 'set origin' menu doesn't work for me. The motion data is pmd and I also imported it by mmdtools. I couldn't pack the model data so there's no blend file, sorry. Anything would be really helpful. Another solution of controlling lights would be also appreciated.

I just answered a similar question. The solution should work for this as well: https://blender.stackexchange.com/questions/283900/is-it-possible-to-make-a-text-follow-an-object-assign-to-an-avatars-rig/283901?noredirect=1#comment488034_283901

Thank you sooo much!! Problem solved! This really helped me a lot


text:
why does parts of my objects disappear when moved outside of "beam"
I created this scene a while back and I don't remember adjusting any settings involving clipping.
But there is a clipping "beam", and everything outside of it gets clipped away. The beam is not connected to the camera.
What is that "beam", and where is the settings for it? - any help, is much appreciated.

It looks like Clipping Border (which allows you to limit the view), try AltB to enable or disable.

That was it Thanks a lot
https://docs.blender.org/manual/en/2.79/editors/3dview/navigate/clip.html


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How to apply freestyle on only one mesh?
I have a scene in Blender in which I want to apply freestyle effects to just one object. Is this possible. How can I do it?
(I'm using Cycles)

In the freestyle settings, check the "collection" option for selection by, then you can add your one object to a collection, and choose that collection in the settings menu below.


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IK Arm rotates in wrong direction
After having done my IK rig, I notice that moving my arm control bone moves it in the wrong direction. I am not able to put my arm in the correct way.
How I want to pose my arm (sorry, best photo I could find ):

How it is (tried to pose same as wanted result) :

I have tried rotating the pole target bone to 0 and other rotations, but this twists the mesh in some gruesome ways :

Shoul I restart my rig, twist the mesh itself or are there parameters I forgot?

could you please share your file? (delete all the unnecessary elements) https://blend-exchange.giantcowfilms.com/

I am sending the blend file.

Here is the file :

I would not build the armature this way but anyway, I wonder if your problem is not simply because you need to bend the arm a bit in Edit mode, tell me if that fixes the problem

Can I bend directly the vertices or the armature? - P.S. How would you build the armature? I knwo it is not a human character so the face part might be a bit more complicated

the armature, see my answer

I would not build the armature this way but anyway, you simply need to bend the arm a bit in Edit mode so that Blender knows the correct orientation (same for the legs).

I found that the correct angle for the pole would be 90° However if i get to 90° the big deformation on the shoulders is showing up

IT..... WORKS ! Thank you so much!


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How easy is the new Blender to pick up?
So, I used to use Blender a lot in the past for photography/game development purposes. I've recently decided to start using it again, however it feels so very different from when I last used it roughly a year ago...
Is it going to be easy to pick up from where I left off or am I going to have to re-learn the program from scratch?
Thanks,
Cam.

Totally fluent transition... (in my opinion)


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Image will not show through transparent object
So I imported an image using the "import images as planes" plugin. Then placed it in a box, and added a transparent cylinder in front of it.
As you can see from the screenshot the brown of the box, plus other objects shows through, but the image does not.
I am guessing there is some setting I need to adjust on the image/plane to get it to show through?
Screenshot, plus the shaders created by the plugin:

It's because the import images as planes tool sets the blend mode for the material to Alpha Blend, and you're using Eevee.
Your options are to switch to Cycles or change the Blend Mode to Opaque.

Thanks! blend mode = opaque works for me


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Black and white view after splitting window
I have a huge problem (I'm new in blender so it maybe be something stupid actually), after splitting the windows and go back to only one view window, I can not see colors anymore. At the beginning, when splitting the window, the left window is normal (with colors if you had an object or something with a color material) and in the right window you had a black and white image. Ok, after joining the windows I only have forever and ever the black and white view :/, the only way for me to see the material's colors is to render the image. I even  tried to delete and reinstall Blender (2.8 and 2.81a) but I still the black and white view. Can someone help me with this issue?

If I'm understanding your question correctly, the issue is that you are in Solid view and want to see the Material Preview.
Click this button at the top right of the 3D viewport and you will see the material attached to the object.

As an aside, you can change the color of objects in Solid shading mode by scrolling down towards the bottom of the Material Properties tab and choosing a color for the object under Viewport Display.


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v3.0 not using dual GPU's, 2.82 does (same exact file)
I've always used 2 GPU's in blender and it's always rendered 2 tiles at a time. Not anymore...
I recently updated to blender 3.0, after about a year of not using it at all. On rendering my first image with it, I note it seems to no longer use both of my GPU's (identical 1070's).
If I load the exact same file in v2.82, it does use both. It renders 2 tiles at a time, no matter if I have SLI enabled or not.
Back in 3.0, only 1 tile at a time.
Can anyone tell me why 3.0 is not using both and how I might fix it?
In both versions, both of the GPU's are enabled for CUDA, they are ticked and not greyed out and I receive no errors.

Hi :). Blender 3.0 uses Cycles X, a completely redesigned engine, which renders one tile at a time no matter how many cores are computing it. Don't worry, it won't be any slower.


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Displacement in viewport looks NOTHING like render? Adaptive or not makes no diff
I have an appended procedural texture with displacement that looks great in the viewport.
As soon as I render it, it looks like utter trash. It doesn't even resemble the planar version of the displacement texture.
I thought it was an issue with adaptive subdiv, but no - just tried with normal subdiv and same issue.
V3.0 used, and it makes no difference what dicing scale or camera is used.
Screenshots attached showing the same camera view in both viewport and render window, subdiv settings are visible.
CUDA GPU's enabled and in experimental mode (which shouldn't even be necessary for regular subdiv, but anyway...)
What the hell?
Images link in case the inline doesn't work:
https://postimg.cc/gallery/Jhhw32z
Blend file: https://easyupload.io/1z284k

Hi :). The Wave Texture Distortion is keyframed. Viewport shows Distortion = 10, but it renders with only 1 which looks bad. Redo or remove your keyframes ;)

Holy freaking cats! Thank you, this was driving me absolutely mental.

Anytime ;) good luck with your project


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Rigid Body Problem - Objects not interacting with curves correctly
I am trying to make my own Jenga tower with blocks sliding out to practice rigid body simulations. When my blocks fall, they are interacting with the bottom of the plane but slide right through the beveled mesh. The plane, as well as the blocks, are set as rigid bodies and the blocks are active while the plane is passive. Here is the blend file if anyone wants to take a closer look. https://www.dropbox.com/s/iwyg5bh0otwjx9l/JengaBlockCopy.blend?dl=0

Change to shape "mesh" and "deform"

result:

I'm assuming you did the simulation when that plane was flat, then you baked the simulation and then edited the plane to have a bevelled wall. To fix this, go to the Rigid Body cache, delete the bake, and re-bake. Make sure the plane Shape option is set to Mesh and not Convex Hull.

Hmmm, I did exactly what you said and the blocks still slid right through the curved edge.

Nevermind! I had to add a solidify modifier to the plane! Thanks for the help!


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Accessing Geometry Nodes mesh data from Python
I have a mesh object created by geometry nodes - it's basically a plane divided into smaller segments.
In the spreadsheet, I can see the number of faces and vertices. But when trying to access this information from Python, it appears that Python only sees the base mesh (to which the geo nodes modifier is applied). That is - Python only sees 1 face, not N faces.
Is there a way for Python to access the output of the geometry nodes modifier?

Check out the first code example here.

This code prints the number of faces before and after modifiers (original data vs evaluated data):
from bpy import context as C
dg = C.evaluated_depsgraph_get()
ev = C.object.evaluated_get(dg)
print("Faces:", len(C.object.data.polygons))
print("Evaluated Faces:", len(C.object.evaluated_get(dg).data.polygons))

A further question - How do I iterate over all vertices on an evaluated face/polygon? It doesn't appear to be the same as the mesh data before modifiers are applied.

Nevermind - I figured it out. for Vert in mesh.data.polygons.vertices provides an index I can use to call  on the coords in mesh.data.vertices...


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is there a way to hide the cut when 2 objects need to appear as one?
I've been trying to find a way to have 2 objects appear as one.  For reasons this has to be the case for the game I'm working on.  My question is, is there a way to hide the line that appears when you seperate faces into a different object.  I've tried fixing normals but that hasn't appeared to have done anything.  Any suggestions, is this even possible?  Please see examples for reference.  Much appreciated for any responses.

https://blender.stackexchange.com/questions/53749/normals-changed-after-separating-object-in-2-pieces   https://blender.stackexchange.com/questions/133613/blender-material-issue-while-snapping-two-objects-snaps-together   https://blender.stackexchange.com/questions/159008/rip-secret-door-showing-no-trace-of-edges-into-shade-smooth-sphere/159020

Yes.
The reason for the visible line is that the normals are discontinuous.  Once you cut faces off from each other, those separated faces are no longer affecting the normals of the vertices at the cut.  So there is a sharp difference between the normals on one side of the cut and the normals on the other side of the cut.
You can use custom normals to restore the normals to what they were before the cut, by using a data transfer modifier:

Before cutting the object, duplicate it.  Don't move the duplicate, just leave it right on top of the original (but you can hide the duplicate, or move it to another collection, if you need to see what you're doing.)  Then go ahead and cut the original.

Give the original(s) a data transfer modifier targeting the duplicate.  Set it to copy face corner data, custom normals.  Set the mapping to "nearest corner of nearest face."  You may see a warning to enable autosmooth on the modified mesh-- go ahead and do that if it's not already set to autosmooth (in properties/object data/normals.)  If your original is two or more objects, each object will need the modifier, and each object will need to be set to autosmooth.

The correct normals should be apparent now.  To make them permanent, apply the data transfer modifier(s).  After that, it's safe to delete the duplicate.

Awesome I tried this and it worked however the tech artist still had a couple of issues that now the object (once imported into unity) would no longer reflecting light in game.  So something else I tried was actually selecting the faces and splitting them then separating them and that seems to have fixed the normals problem.


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Smoke showing in Preview, but not in finished render
I've been trying to render a weapon, with a passive red smoke behind it - smoke is showing up in the layout tab and is shown when the animation is played. But when trying to render it, no smoke is shown.
The engine I'm using to render the smoke is Cycles on Experimental. I've tried baking the smoke but without success.

Please add screenshots of the viewport and rendered scene and the shader you are using on the smoke.

Do you have proper smoke material?

Have you long enough  camera  range?  Have you changed the volumetricks number  of passes from zero? Sun is not a light source that can be  used  on smoke.  You need an other sort of  light I think. Some wild stabs  in the dark  from  a noob. :)


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Problems trying to use the builtin Spin tool from a Python script
I'm hoping someone can help me use the 3DView->Edit Mode builtin tool 'spin'. I've extruded a number of vertices and their edges to form a (closed) 2D face. The object is named called 'RocketNozzle'. I want to use Python to 'spin' this face around the z-axis. I can do this manually from the 3DView editor, but am running into problems using Python to script it.  The code below shows my current attempt. I'm basing my approach on these two articles:

how to change a tool through the Blender API
how to set the active tool

I know the line with bpy.ops.wm.tool_set_by_id(override_context, name="builtin.spin") is working, because the spin tool is shown active after this line executes.
But I can't get a reference to the active tool back into the script! I think if I can successfully get a reference to the active (spin) tool, that I can set the three properties I want, and then call tool.Execute() ?? to make the spin occur. I just can't seem to get a valid reference to the tool back into the script.
TIA for any help, insights, or links!
# lots of code to get to this point ...

# The object at this point is a two-dimensional face having many vertices/edges that form the outlines of the inner and outer walls of a complex curved surface
# rotate the face around the z-axis
# Select the entire object
bpy.ops.object.mode_set(mode = 'OBJECT')
obj = bpy.data.objects[PartName]
# Go to Edit Mode
bpy.ops.object.mode_set(mode = 'EDIT')
# Select all of the vertices
bpy.ops.mesh.select_mode(type="VERT")
bpy.ops.mesh.select_all(action = 'SELECT')

# Spin them all around the z-axis
# Select the builtin Spin tool from the Object->Edit menu
# [how to change a tool through the Blender API](https://b3d.interplanety.org/en/how-to-change-current-tool-through-the-blender-python-api/)
# [how to set the active tool](https://blender.stackexchange.com/questions/178959/enable-disable-3d-cursor-tool-properties-from-python)
area = [area for area in bpy.context.screen.areas if area.type == "VIEW_3D"][0]
override_context = bpy.context.copy()
override_context['window'] = bpy.context.window
override_context['screen'] = bpy.context.screen
override_context['area'] = area
override_context['region'] = area.regions[-1]
override_context['scene'] = bpy.context.scene
override_context['space_data'] = area.spaces.active
# Set the active tool to be the spin tool
bpy.ops.wm.tool_set_by_id(override_context, name="builtin.spin")
# Get the active tool
# (https://blender.stackexchange.com/questions/178959/enable-disable-3d-cursor-tool-properties-from-python)
from bl_ui.space_toolsystem_common import ToolSelectPanelHelper

######################
### Manual steps here, 'cause the next line throws an exception
tool = ToolSelectPanelHelper.tool_active_from_context(override_context)
# Using override_context in the line above, throws an exception :
#    line 710, in tool_active_from_context
#    space_type = context.space_data.type
#    AttributeError: 'dict' object has no attribute 'space_data'
#
tool = ToolSelectPanelHelper.tool_active_from_context(bpy.context)
# Using bpy.context as shown in the lineabove causes the next line to fail with the message
#    AttributeError: 'NoneType' object has no attribute 'steps'
tool.steps = 32
tool.angle = 360
tool.axis = [0,0,1]
### Make it spin somehow
tool.Execute()  # not sure if this is correct....
### End area of manual steps
######################

# copy the lines from here to the end and paste them into Blender's Python Console

# remove duplicates again, to ensure the spin did not add any extra unwanted vertices
#  also change the merge distance (make it larger) in case the duplicate vertices from the spin don't quite line up exactly
bpy.ops.mesh.remove_doubles(threshold=0.01, use_unselected=True)

# more code here...

```

Instead of messing with changing the tool, just call it directly? bpy.ops.mesh.spin(angle=3.14159, center=(0,0,0), axis=(0,0,1))

Personally would ditch using the tools / operators completely. Related https://blender.stackexchange.com/questions/212786/how-to-create-cylinder-with-varying-radius-at-different-height/212816#212816  and https://blender.stackexchange.com/questions/114126/how-do-i-draw-a-parametric-column-or-cylinder-with-varying-radius-using-python/114129#114129

I agree with Ron Jensen's comment.  There's no reason to override the spin tool, just invoke it with settings that accomplish your goal.  You can replace most of your code with:
# lots of code to get to this point ...

# The object at this point is a two-dimensional face having many vertices/edges that form the outlines of the inner and outer walls of a complex curved surface
# rotate the face around the z-axis
# Select the entire object
bpy.ops.object.mode_set(mode = 'OBJECT')
obj = bpy.data.objects[PartName]
# Go to Edit Mode
bpy.ops.object.mode_set(mode = 'EDIT')
# Select all of the vertices
bpy.ops.mesh.select_mode(type="VERT")
bpy.ops.mesh.select_all(action = 'SELECT')
bpy.ops.mesh.spin(steps=32, angle=2*pi, center=(0,0,0), axis=(0,0,1))
# remove duplicates again, to ensure the spin did not add any extra unwanted vertices

#  also change the merge distance (make it larger) in case the duplicate vertices from the spin don't quite line up exactly
bpy.ops.mesh.remove_doubles(threshold=0.01, use_unselected=True)

that is, delete everything between
# Spin them all around the z-axis

and
# copy the lines from here to the end and paste them into Blender's Python Console

inclusive and replace them with
bpy.ops.mesh.spin(steps=32, angle=2*pi, center=(0,0,0), axis=(0,0,1))

This has the added bonus that it won't throw exceptions and you can execute it all within the script.

Wonderful, thank you! FWIW, I also needed to import math, and use math.pi in the final script.


text:
Recreating Houdini Paint Smear in Blender using FLIP (Help!)
I saw this amazing Houdini tutorial the other day and was wondering If I was able to recreate it using Blender.
https://www.youtube.com/watch?v=8TvAe3GxNFs&ab_channel=Entagma
My results, however, are less than satisfactory. I added a screen grab of what my result looks like.
I end up with weird tearing and floating bits. My Viscosity is set to 5 which is large, but according to this video, 5 looks about right to me (folding nicely like paint):
https://www.youtube.com/watch?v=vt2wjrm7pIs&ab_channel=BlenderRookie
What am I missing? My resolution is already set to 100 and I made sure to reduce the speed of the collider just in case that was causing any issues (although the collider has 16 sampling substeps which should be plenty).
I would appreciate any help I can get.
Thanks!


text:
How can I align two faces in edit mode
I have two triangular faces that are connected with one edge (one object, in edit mode). I would like to move the second triangle into the plane of the first triangular face. This means that the third not connected point will have to move.
This would be easy if the plane would be x,y or z by using the scale trick, but I would like for it to work in any given plane. How could I do this?

I think the answer is: yes you can.

Select the connecting edge and snap the 3D cursor to it
Set the pivot point to 3D Cursor
The connecting edge still selected, add a custom transformation orientation and keep it as orientation

Now

Select the first triangle (the target)
Use ShiftNumpad 1 or ShiftNumpad 3 to be in orthographic view aligned with this triangle and so that the connecting edge is aligned to the view. This is useful in order to snap as we want later.

To snap:

Enable snapping, set it to vertex, snap with closest, project onto self and enable it for rotation

To rotate:

Select the opposite vertex (the one of the other triangle)
Rotate R, hit Y to rotate around the connecting edge
Set the mouse cursor onto the opposite vertex of the target triangle

To rotate to the opposite:

Rotate R, hit Y, then hit 180 on the numpad

Script wise getting the rotational difference of the linked  faces normals and rotating about edge does the trick too.   Similar to https://blender.stackexchange.com/questions/68609/lock-edge-length-editmode

This was exactly what I was looking for. A bit strange that the functionality is not in Blender itself. There is an option via cleanup that does pretty much this, but it only works on one plane (with more than 3 vertices of course).

@takje I think this is not built in because Blender is still essentially quad based, so this generally don't matter. But consider batFINGERS answer as his answer leads to a much more simple process.

@batFINGER Yes but you could generalize it to two quads (that are each perfectly planar) and you would have the same problem in my view.

Script Version

For two triangles can use the rotation difference of the hinge edges adjoining face normals.  In angle axis format this will be the angle required to rotate, and axis should be parallel to the hinge edge.
To use, edit mode, edge selection.

Select hinge edge.
Shift select edge on tri face you wish to rotate to
coplanar.
Hit run script.

Test script.
import bpy
import bmesh
from mathutils import Matrix

TOL = 1e-7
context = bpy.context
edit_object = context.edit_object
me = edit_object.data
bm = bmesh.from_edit_mesh(me)

e0, e1  = bm.select_history[-2:]
# connected faces
f0, f1 = e0.link_faces

if all(e in f1.edges for e in (e0, e1)):
    f1, f0 = e0.link_faces

while f0.normal.angle(f1.normal) > TOL:
    axis, angle = f0.normal.rotation_difference(f1.normal).to_axis_angle()
    evec = (e0.verts[1].co - e0.verts[0].co).normalized()

    if axis.dot(evec) < 0:
       axis.negate()

    bmesh.ops.rotate(bm,
            verts = f0.verts,
            cent=(e0.verts[0].co + e0.verts[1].co) / 2,
            matrix = Matrix.Rotation(angle, 3, axis)
            )

bmesh.update_edit_mesh(me)
me.update()

Much more easy... once you have the script : )

Cheers.  Still confused how to do this in one hit from rot dif. Ended up doing the ugly iterative thing. .. Tried looking at normals and dot products changing orders..???  btw noticed galdalf answered other q the other day.  Agree, tis a shame.

In fact we only have to move one vertex. So if we use the altitude of the triangle, it can be move from the altitude intersection point in the altitude distance and colinear to the altitude of the opposite summit vertex (?).

While I picked the other one as the answer since it is a little more generic, I think I will use this one the most. I haven't used any scripting yet before this, but I really like the simplicity.

@lemon since the other two verts are on the axis I didn't bother to find the "other" vert.  The issue is (as I see it) rotating the wrong way, and some test or order to go the right way.  Could project the normals down the axis as 2d vectors and get the signed angle difference but getting to overkill for an answer.

To Rotate the vertex into the plane, follow @Lemon's answer, or a variant.
To Project the vertex onto the plane:

With pivot set to 'Active Element'

Create a Custom Orientation from the face/ 3 vertices which will remain stationary.
This is  the '+' in the Orientation dropdown. You may want to add this to your Quick Menu, or create a shortcut for it. You may also want to set it to 'Use after Creation' and/or 'Overwrite Previous'. Those settings will persist.

Select the vertex/vertices you want moved, with one of the stationary vertices last, so it's active.

Hit SZ0

Actually, for rotation, these steps can be used in combination with parts of @Lemon's answer: use them to project a ShiftD duplicate of the vertex you want to rotate onto the plane, which can then be used as a snapping target for the rotation, and deleted after use.

The answer is: You can't.
But you can trick Blender to do so:
Let's say we have two triangle faces in random locations. They are part of one object:

What we can do to align the faces is this:
1) Since we cannot automatically align the faces in edit mode, we will select one face, and P to separate it into another object, and transform origin to geometry:

2) Align the two objects by selecting both, going to object > Transform > Align, and SHFT-RMB on all axes. This is the result:

Now the objects are aligned so that they are only visible as "one" object.
If you want to connect the faces when making one object, follow these next steps. If not, then skip to step 4.
3) Select one, move it down to about the bottom of the other, (try to make exact as possible), and rotate the object so that is perpendicular to the former like this:

4) Select both objects, and press CTRL+J to join to one object.
Result:
(optional) 5) Join the faces on one edge. Origin to geometry first, then go to edit mode. Choose select edges and select the edges where the triangles meet.

Now press F to mark as a face. This is the final result when one face is moved:

The faces are aligned and joined.
I hope this solved your problem.
Note: Please don't mess up the location of the faces, and if you do, Don't Worry!
Just press CTRL+Z, and you're fixed.

"I have two triangular faces that are connected with one edge"

There is always a longer way.


text:
Color individual faces after modifier
It is possible to color individual faces of a model by going to edit mode and assigning different textures to each face.
I'm using a low poly model to which I apply a subdivision modifier and subsequently a decimate modifier. When I go to edit mode I only see the faces of the original mesh. This does not map well with the final result and therefore I'm not able to color it appropriately. How could I color individual faces without applying the modifiers.

Once you use a Generate Modifier (decimate counts as well) you don't have much control over the mesh anymore. Since modifiers are by nature dynamic, you can't change individual faces, since they might not exist in another frame.
Usually you would use vertex paint in a situation like this, but that's also not easy.
One method to cheat I can think of right now is: Use a texture, unwrap your model and make the decimate modifier respect the seams. It's fiddly, but you might get this working.

A bit unfortunate because the unavailability of the mesh make a couple of non destructive workflows quite hard. I've had other examples where I wanted to extrude a face after a modifier which is simply not possible. I think I'll just make a copy which I hide and apply the modifiers.

Frame change post handler
Note this answer popped up as a thought bubble  wrt commenting on the other python answer re randomly colouring faces,  It is possibly of little use to OP, depending on what kind of control is needed. As OP commented using an applied copy could also be a way to produce a map to color faces in handler.

Render result using handler script 2 levels of subsurf above, 4 below

As a proof of concept wondered whether changing the material indices on faces of the evaluated object of a modified mesh would work.
It does not show in the material preview but renders Ok.

The default cube with 4 materials and one level subsurf
Proof of concept script, randomly sets material index of  each modified face for each frame.
import bpy
from random import choice

choices = list(range(4))

def random_col(scene, depsgraph):
    cube = scene.objects.get("Cube")

    cube_eval = cube.evaluated_get(depsgraph)
    for f in cube_eval.data.polygons:
        f.material_index = choice(choices)

# comment line below when finished testing
bpy.app.handlers.frame_change_post.clear()
bpy.app.handlers.frame_change_post.append(random_col)

To instead set all faces material indices once would calculate the list  outside handler, and use to set indices within handler.

I created a script to help with this:
import bpy
import bmesh
import random

def view_materials():
    ob = bpy.context.object
    assert ob is not None and ob.type == 'MESH', "active object invalid, select a mesh"
    materials = ob.data.materials.items()
    bpy.ops.object.mode_set(mode='EDIT')
    mesh = bmesh.from_edit_mesh(ob.data)

    indexes = [[face.index, face.material_index] for face in mesh.faces]
    material_indexes = []
    for index in indexes:
        tuple = (index[0], materials[index[1]])
        print(tuple)
        material_indexes.append(tuple)
    bpy.ops.object.mode_set(mode='OBJECT')

def make_random():
    ob = bpy.context.object
    assert ob is not None and ob.type == 'MESH', "active object invalid, select a mesh"
    materials = ob.data.materials.items()
    bpy.ops.object.mode_set(mode='EDIT')
    mesh = bmesh.from_edit_mesh(ob.data)
    for face in mesh.faces:
        face.material_index = random.randrange (0, len(materials),1)
    bpy.ops.object.mode_set(mode='OBJECT')

print('before')
view_materials()
print('making random')
make_random()
print('after')
view_materials()

Results:
    before
(0, ('Material', bpy.data.materials['Material']))
(1, ('Material', bpy.data.materials['Material']))
(2, ('Material', bpy.data.materials['Material']))
(3, ('Material', bpy.data.materials['Material']))
(4, ('Material', bpy.data.materials['Material']))
(5, ('Material', bpy.data.materials['Material']))
making random
after
(0, ('Material.003', bpy.data.materials['Material.003']))
(1, ('Material', bpy.data.materials['Material']))
(2, ('Material.003', bpy.data.materials['Material.003']))
(3, ('Material', bpy.data.materials['Material']))
(4, ('Material.001', bpy.data.materials['Material.001']))
(5, ('Material.002', bpy.data.materials['Material.002']))

Instructions for use:
Create your color pallet by creating as many materials as you want in the materials.
Select your object, then run this script. It will randomly choose a selection from the color pallet and put it on your cube or whatever.

A issue here is a modifier like subsurf subdivides the faces of the original and displays the modified mesh.  (eg  Apply the default subsurf modifier to default cube and it will have 24 faces. The OP does not wish to apply the modifier.  Your script only randomly colours the original 6 faces.

Yes, it is.
Go from Object mode to Edit mode. (It's a pull down over a perspective view window)
Press the Face Select button (of the three icons in a row, vertex|Edge|Face select)
Left click on faces to select them (use shift to add more)
Go to the Materials editor, choose or make the material you want.
Press the "Assign" button to assign the material you have selected to the selected faces.

Please read the question carefully. The OP is referring to faces created by a  modifier.  Using method above would require applying the modifier which the OP states they do not wish to do.


text:
Blender video editor cut strips issue
I used to use Blender one year ago and just reinstalled it 2 days ago. I am facing an issue that seems to be a bug to me.
I am on archlinux, last 17:2.81.a-5 blender version with no library issue.
In video editor mode, I upload a mp4 video. When I cut (K) a strip in two strips, half the time (more or less) it cut it at the right time line but the cut is performed between 2 and 10 frames later in the time. I can not fins any sens to this behavior, so I think this is just a bug.
For example, I have a strip from 0 to 200 frames, I cut it at the frame 100 and now, the end of the left strip is corresponding to the 96th frame, not the 100th. So, I have 4 frames in the right strip that should be on the left strip.
It does it pretty randomly.
I tried all the different cuts (soft, hard), with keymap, without.
Could it be a bug from the last release?
Any idea?
Thanks for your time.

Your source file may have variable frame rate. You can use MediaInfo to check: https://mediaarea.net/en/MediaInfo
If it has VFR you'll need to re-encode it with ex. Handbreake or any other GUI for ffmpeg: https://handbrake.fr/

This is the right answer, I figured it out few days ago and was trying this solution.

@yoarch Please don't reply "Thanks" as an answer or comment, instead upvote the post that helped you. If you feel it completely solved your issue consider marking it as accepted.


text:
Hard edges in render
I've been having this problem with several models and I can never figure out what the issue is.

Hard edges are appearing on the model in rendered view despite it being entirely smooth shaded. There are no overlapping objects, it's not the textures, I've recalculated the normals. I have no clue what is causing this.

Is there a normal map involved here?

This could be an instance of shadow terminator artifacts.

I looked up what terminator artifacts are and.. that seems to be it. I added a subdivision surface modifier and that doesn't really help, there are still sharp edges. I don't suppose this problem will be fixed in Blender any time soon?

https://blender.stackexchange.com/questions/91913/some-areas-of-the-mesh-are-dark/91916#91916 https://blender.stackexchange.com/questions/27982/how-to-avoid-terminator-artifacts-while-still-using-smooth-shading-and-the-new-phttps://blender.stackexchange.com/questions/34074/cause-of-alpha-or-black-artefacts-in-render/34097#34097


text:
How can i remove the white dots
I dont know how to remove these white dots. I already tried to make the lamp bigger. More samples does not work aswell. I dont know what can I do?

Showing only the result makes it a bit of a guessing game. Consider sharing blend, or posting screenshots showing settings.

See also https://blender.stackexchange.com/search?q=remove+fireflies

Those white dots look to me like light fireflies. To fix this, use denoising. You can enable this in the second render collections tab in the properties panel.


text:
How can I solve a far away stacking Freestyle line
Im a beginner to use blender for comic

i try a way to make line on faraway object to be small but it still have a result like this. their are the way or some easy method to make a stacking line look doesn't black like this?

I'm not sure if you're already doing this, apologies if so.
You can assign a Distance from Camera modifier to the line thickness in the View Layer Properties tab > Line Style panel.
Before:

After:

You might have to use separate Line Sets for other features whose
detail you want to preserve in the distance.
You can assign the same modifier to Alpha, making the lines more transparent in the distance -  a possible alternative.
As you can see, depending on the resolution of your rendered image, at some thickness, sampling/antialiasing takes over. This might be before your set 0 point; you'll have to tweak the curve / base thickness accordingly.

You can just exclude some edges from the Freestyle line set.

Select your edges
Mark them as Freestyle (Edit > Mark Freestyle Edge)
Check ✓ Edge Mark and the little × to prevent marked edges from being drawn


text:
Confusion Adjusting/Using the Rotation Vector of Bones in Drivers
I am currently using bone drivers to basically rig a model I created using geometry nodes. While I have been able to get around issues when the local orientation of a bone differs from the object, I have met my match with the last drivers I have to create.
Currently I have two bones that head downward. From my understanding, this means that the local orientation of the bones are rotated 90° around the x axis. Using this, I've managed to be able to use the local position of the bones simply by taking the (x, y, z) and converting to (x, z, -y). This has also proven true (with the exception of the -y) for using the local scale of the bones. However, I'm having issues when extending this property to rotation.

When taking the local rotation of the bones and converting (x, y, z) to (x, z, -y), I run into an issue when I rotate in both the y and z directions beyond 0°/90°/180°/270°/(and so on)(but not when rotation in just xy or xz directions). Below I created drivers that align an axis object (blue for z, green for y, and red for x) using the conversion above. When the receiving results as expected, the z axis points the opposite direction of the bone, however it drifts from this orientation when rotating around both the y and z axis. The "working" example has the bone set to (0°, 50°, 0°) with the drivers reading (0°, 0°, -50°). The "issue" example has the bone set to (0°, 50°, -45°) with the drivers reading (0°, -45°, -50°).

At other times I get unexpected results outputs between the bone and the driver. For one image, the bone is locally rotated (0°, 90°, 45°) which the driver reads as (-45°, 0°, -90°) when it should've been converted to (0°, 45°, -90°). Changing the bone rotation to (0°, 90.1°, 45°) does properly convert to (0°, 45°, -90.1°), though the aforementioned issue of the bone no longer lining up with the mesh appears again. I suspect this is a symptom of the same issue.

When compared to how the conversion (x, y, z) to (x, z, -y) works without flaw for using the bone's local position to control an object's location through drivers, I'm left wondering if bones handle local rotation differently that doesn't let the simple rotation matrix to work.

A possible solution from additional testing may be setting the bone to use XZY Euler when setting rotation instead of keeping the bones on Quaternion or XYZ Euler. I am not sure if there is a problem keeping the drivers on Auto.
Hopefully someone can confirm this for me or provide an explanation for why this is the case.


text:
How to switch the property panel?
When I finish creating an object, or select an object, I want it to automatically from other switch to the object properties panel, but i can't find the relevant interface in the panel.

but you know, that if you switch it once...and create a new one...it keeps on that tab, don't you?

Well, I just want to make the operation experience better. Is it possible

yes, might be possible with python and use as startup file ...should be possible, although i think it isn't worth the effort. You can do a lot of time savings by other things, which aren't perfect in Blender, but saving the time for one click for the day (assuming you are working only on one Blender file)

i see, thank you

the python commmand is bpy.context.space_data.context = 'OBJECT'


text:
How to create a permanent timer？
i use bpy.app.timers.register add timer, but it does not work after open or drop a new blendfile,
can i create a permanent timer?
that's my code:
@persistent
def check_storey_info11(context):
    if bpy.context.scene.active_storey != '':
        context.area.spaces.active.region_3d.view_rotation.angle = 0

    return 0.1

class StoreyWidgetGroup(GizmoGroup):
    bl_idname = "VIEW3D_GGT_use_storey"
    bl_label = "Storey Gizmo Group"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'WINDOW'
    bl_options = {'3D', 'PERSISTENT'}

    @classmethod
    def poll(cls, context):
        return True

    def setup(self, context):
        bpy.app.timers.register(functools.partial(check_storey_info11, context))

You need to use @persistent decorator see https://docs.blender.org/api/current/bpy.app.handlers.html#persistent-handler-example

Re-register a timer when open a new file
import bpy
from bpy.app.handlers import persistent

debug_int = 0
context = None

def timer_fn():
    global debug_int
    context
    print(debug_int)
    debug_int += 1
    return 1.0

bpy.app.timers.register(timer_fn)

@persistent
def run_when_open_new_file(dummy):
    print("new file detected")
    if not bpy.app.timers.is_registered(timer_fn):
        bpy.app.timers.register(timer_fn)

bpy.app.handlers.load_post.append(run_when_open_new_file)


text:
How to do small amounts of fluid?
I want to have some tiny drops of water at a time fall into a mug. I don't want to flood everything. I can't figure out how to do this, help would be greatly appreciated. I've spent the last 5 hours on this. (Also, why do simulations just refuse to work sometimes?)

They sometimes refuse to work because they are part of the BPUUnion. As for your other question…

an easy way would be to animate the inflow object scale

If you are going to create only a few drops so that it's no problem creating them manually, you could do the following:
In my example I took one sphere and made it a Flow object. Although I just want the geometry to become a drop-shaped fluid, I've set the Flow Behaviour to Inflow.
Then I disabled Use Flow on frame 1 and set a keyframe, enabled it on frame 2 and keyframed it, and disabled it again on frame 3 with a keyframe.
Now I duplicated this sphere twice and moved the duplicates to slightly other places (not necessary, but I wanted different locations). After that I moved the keyframes on the Timeline to later frames.
Instead of behaving like an inflow, the spheres now create a drop of liquid on that frame which has their Use Flow option enabled. Since it's immediately turned off afterwards, the simulation won't be "flooded". Of course the drops could be smaller than the ones in my example.
Result:

File:

Using quick liquid You've set up your three objects, the coffee cup (the effector), the emitter (inflow) and the box to put the simulation in (domain).
You can select the emitter, (inflow) you can turn off the inflow at a certain point in your animation by unchecking the "Use Flow" box and then setting a key:

In this example, I am preventing my coffee sim from overflow.
Other answers on this forum have said to make just a couple drops fall you can also use meta-balls as particles.  I have tried this with pretty good results.


text:
How do I freeze a rigid body in its position?
So, I dropped a suzanne using rigid body physics, I want to freeze it in the pose it landed in and remove the rigid body physics. How would I do this?

If you want the animation to stop at a certain frame, you can for example keyframe the Dynamic on option at frame X and keyframe it off at frame X+1:

If you want to completely remove the action, select the object, go into the header menu > Object > Rigid Body > Bake to Keyframes and choose the frame you want to freeze in the pop-up panel:

But I want to save that position and remove the rigid body sim

ok so does my edit answer?


text:
How do I keyframe a shader node?
I want to keyframe this value to change, how might I do that?

 RMB on the Fac field and pick Insert Keyframe, or hover your mouse over the property you wish to add a keyframe to and press I.

Or move the mouse over it and press the I key.


text:
How to render objects with self illumination?
Pretty new to blender, but i feel like i have gotten off to a good start. With that said, i have one issue that i have been struggling over the past week to get a hang off, and that is how to render my character with self illumination.
I am trying to achieve something similar to how they did Ori (detailed here: https://www.youtube.com/watch?v=m8lOwrWNbEY around the 6:10 mark).
I have an unlighted scene with transparent background. I either end up with something that is fully illuminated (white silhouette) or when trying a few other solutions (like this: Making Textured Surface Emit Light) I just end up with weird shadowing.
Any ideas on how to proceed?

what does your material or scene look like? What is your current output? Needs more information or your blender file

Actually a screenshot with what you have achieved so far would be great and maybe a still frame of Ori how you want it to look as a comparison.

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

This answer is just a guess. I didn't get much detail at 6:10 of the video, it just says "100% self illum diffuse".
So what I just did was taking an Emission and a Diffuse shader and mixing them together somehow with a Layer Weight node, since Ori looks like the emission is stronger towards the edges.
The rest is playing around with the Color Ramp and the Blend value on the Layer Weight node to get something that works somehow. Just note that the color of the Diffuse shader as well as the Color Ramp's right slider are not full white but light grey.
Of course you could do something similar with a Principled BSDF shader. If this helped, that's fine - but I'm not sure if this the look you want. (The eyes have a different material.)

Thanks for the super quick reply. I was definitively thinking in the right terms here, but you made it all click together. Worked exactly as i wanted it!

@starfckr Oh, nice to know that it's what you wanted. Glad I could help. By the way, your username makes me think of Nine Inch Nails.

That is correctly thought on your end. Good catch! :)


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Creating Overlock-Seam
I would like to ask if anyone has any experience with building up textiles/seams. I am trying to create an overlock seam. Can anyone give me suggestions on how to build up a seam like the one in the picture as easily and quickly as possible?
Very dear greetings
Silvana

How close-up does the result need to be in your final image?

Hi, congrats on your first question here!  If my answer below didn't answer your question then some more detail could be helpful, such as end use (modeling/texturing for games has important differences from doing it for animation, for example), how closely this will be seen, etc.

It is for a picture rendering. I will render the whole product (1900mmx900mm) and some close ups. Therefore there will be some detail shots.

“ . . . how to build up a seam like the one in the picture as easily and quickly as possible . . . ”  For ease and speed there are two main options:  1) a texture of an overlock seam can be used to sculpt a mesh, or 2) a simple model similiar to a half-cylinder with a tiled texture of an overlock seam.
For the sculpting option there are tutorials that can be searched for (the Blender Tutorial youtube channel has several recent vids that can help you decide if this solution will work for you and give you search terms for further research if needed: https://www.youtube.com/c/BlenderTutorialBT/videos ).
For the textured model option, first you need to find or make a grayscale tiled texture of an overlock seam.  The one I'm using in this example I made from the pic in your ask in GIMP, and I've packed it into the blend file (link below).  This can be done better, searching for how to make tiled textures should give you more info.
Although the seam model can be any shape appropriate to an overlock seam, the UV map must be made straight over the texture used.  In this example I'm using a z-scaled torus section to demonstrate:

This material uses the same image texture for both the Principled BSDF Node's Base Color and Normal sockets, with a Mix RGB node on Overlay providing thread color:

The torus section has been duplicated and joined to show how the tiled image texture with the UVs layered provides a seamless (no pun intended) effect.  Here's the blend file:

Hello KickAir8p
Thank you very much for your perfect explanation. Worked out great. Best wishes

Glad to hear it!  Since I've answered your question please click the checkmark next to my answer.


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How to combine displacement and material
I need to combine a transparent displacement with a material. See Screenshot:

This is the result I need to achieve:

My problem is the mix shader. Either the material is perfect and the holes are almost not visible or reversed. It is a jacquard -> so a 3D mesh with a textile surface/material.
Can anyone help me with that?
Here my Blender-File:

You'll need to pack the images into your Blend file (File > External Data > Pack Resources) and re-upload it so that we can see what's going on.

Hi :). Any reason you're using a displacement output to mix in a transparency? You're also not using the displacement input at all :)

If the answers below didn't answer your question then pls let us know what else you need.  And thanks for posting your blend file, but John Eason's right, the texture map you're using isn't packed into it.  You also might consider posting a .blend that has only what's needed to see (and hopefully fix) the problem -- only that model (or a stand-in), only that material, lighting, etc.

Don't mix displacement with a shader.
Use the dedicated Displacement input.
For transparency use the Alpha channel input in Principled Shader.
example of material shader + with transparency + displacement

In this example the Magic Texture node is standing in for the grayscale image texture to be used for both a Displacement map and a Transparency map:

Note the two different Color Ramp nodes used to make the "deep" parts of the Displacement input also the transparent parts of the input for the Mix Shader node's Fac socket, each adjusted for best effect.  Your mileage may vary, of course -- you'll probably need different positions for the Color Ramp sliders. And in the upper Color Ramp using a very light gray instead of white for the left slider will make the visible part of the material a smidge more transparent, which could make it look more like fabric.
Edited to add:  I forgot something important - in either the Sidebar (n-panel) > Options tab > Settings > Surface > Displacement field, or the Properties area > Material Properties tab > Settings > Surface > Displacement field, the field should be set to either Displacement Only or Displacement and Bump.  Without that the Displacement node won't displace.  With that my earlier recommended Scale value is very wrong, you want something much lower (in this example I used 0.032).  Also please note the Plane and Cube have a Subdivision Surface Modifier using the Simple algorithm at 8 levels -- although that would normally be far higher than needed, Displacement (unlike Bump) requires a mesh dense enough to displace, and you're working with a detailed fabric.