text:
Brownian Motion
trying desperately to prepare a short animation of the inside of a cell. I want to show little proteins bouncing around inside the membrane. I have 3 problems, I will post all 3 separately because it seems those are the rules. I've also uploaded the blender session below.
problem #2: is there any way to introduce Brownian motion to my particles?   I want them to float around randomly a little bit.  Only thing I can think of is increasing bounciness so high that it appears to keep moving, but after about 20 frames it all stops moving.

https://www.mediafire.com/file/upw5904htbfry0s/Phospholipids_and_brownian_motion.blend/file

please first read you answers and update your file/screenshots accordingly. Thanks.

If you turn off gravity, you can add a turbululence force field like this:

Give it some strength (like 200) and bigger noise amount.
So you get something like this:

Play around with the values to get a feeling what they do.
You can also animate this values or even animate the movement of your force field.

phenomenal.  it worked. thank you!

Pls click the checkmark left of my answer, if it helped. Thanks.

sorry, forgot.  done!


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rendering transparency in eevee is WHITE background
trying to export with transparent background in Blender 3.  Always end up with white background no matter what I do.   I did a test on a new project and was successfully able to export with transparent background... so that at least means I know how to do it in theory.   However something is preventing it in my current job and I have no idea what it might be.
thanks

hello, please share your file: https://pasteall.org/blend/

https://www.mediafire.com/file/axbd1wa1fsvz1rl/Phospholipids+and+brownian+motion2.blend/file

Here is your Compositor setup, that's why you end up with a white background. You either need to remove your Alpha Over or disable the Compositing option in the Output panel > Post Processing.

source: Stack Exchange

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

sort: votes


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pivot point issue
I'm trying to recreate the animation in the fig below.   Having a really hard time with pivot points though, any advice?
I create the keyframe at the final position, I select the three strands in the bundle and rotate 180deg then push "i" and click "rotation and translation" for the second keyframe.   Now all the strands rotate together but the pivot point is all wrong.  It make no difference whether I set 3D cursor on the central strand and change "transform pivot points" at the top to go to 3D cursor.  ugh.  thanks!!
https://twitter.com/eLife/status/1484901944778964993?t=BmIbFAvxXISCuV4t1KvycQ&s=19

when the animation will play, it won't take the 3D cursor into account, only the origin of the object, so as Nathan says, the best solution is probably to parent the objects to an empty and rotate this empty

Rotating about the cursor is not really just rotation-- it is rotation, about the object origin, and translation, from its beginning point to its end point.  If you are keyframing rotation of 180 degrees about a cursor, you will not have any rotational movement about the cursor-- just moving from start to end across where your cursor was, while rotating about the object origin.
If you want something to rotate about a different point than its origin, parent it to something that's at that different point, and rotate that parent; if you can't parent it to something, use a child-of constraint.  Create and use an empty to parent/constrain if there is nothing better to use.
If you absolutely can't do any of that, then rotate and keyframe in smaller increments.  Rotate and keyframe in 15 degree increments, 12 times, and it will look a lot more like rotation about your cursor.

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


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collisions vs rigid body
I'm a noob, sry if I use poor lingo.
I made a sphere using a particle system and it instances a little sphere building block.
I then filled the sphere with my little blobs that I want to bounce around wildly inside.
to do this, I:

turned off gravity
rigid body for the blobs
collision modifier for the building block in my sphere particle system.

result:
things bounce around as expected, but they fly right THROUGH the sphere.   I can't seem to get the blobs to bounce off the sphere instead.
thanks in advance!

"Collision" is not for rigid bodies.  It does not interact with rigid bodies whatsoever.  It interacts with soft body and cloth physics only.
To make a collider for rigid bodies, that collider needs to have rigid body physics itself.  If you want that collider to not be affected by gravity/collisions/etc, then that collider should either be set to passive (good performance, but not dynamic) or animated (not as good performance, but can be reoriented.)
In the case of the meshes you're showing, these would almost certainly have to be mesh collision (they are not convex) which means poor collision behavior-- lots of missed collision, really bad performance.  There may even be some self-intersection, in which case mesh collision is going to have a hard time figuring out inside vs. outside.  I would strongly recommend using non-rendering proxy bodies for the actual collision you need, so that you can use sphere or cylinder collision primitives, or some other primitive that roughly represents your rendering shapes.
I can't say how mesh collision interacts with particles-- not everything interacts right with particles, and I haven't tested this-- but if you're saying your particles are rigid bodies, then it sounds like you've already converted them to individual, un-instanced mesh objects, at which point they are no longer particles, so that doesn't matter.  But I may be misunderstanding what you're saying, because "blob" and "sphere" seem pretty interchangeable to me, and I don't see any spheres in your image anyways.

AFAIK, the collision modifier does not transfer to object instance particles: They have their own collision physics. Also, the collision modifier does not directly affect rigid bodies at all. I think what you should do is make a sphere with inverted normals to function as the wall for this system, give it a transparent material, set it as a rigid body, and set the rigid body type to “passive.”

hey that's a GREAT idea.  Thank you!

@jhansen6 I just hope the inverted normal thing works. I don’t remember. Anyway, you’re welcome :-)

I made the sphere. I went into edit mode and selected my sphere mesh.  I went to mesh > normals > recalculate from inside.   It looks like ti swapped because the insides of the sphere are orange now.   However I run the animation and my objects still fly through!   Do I need to apply it somehow after I flip normals?

@jhansen6 No, you should not need to apply anything. I guess that doesn’t work…

I ended up making a bunch of planes instead in the rough shape of a circle.  It worked!    thanks for the idea.

@jhansen6 You’re welcome. PTL!


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one object follows two different paths
(Blender 3)
I have an object that I want to go in a straight line then immediately after follow a circle path.  This has taken 5 hours of my day but no progress. Here's what I've tried.

add > path.  select object > add constraint of follow path.  Modify the path so it looks a bit like a straight line then curves in a lasso.  It has been very hard to get the nice circular motion I want.

animation/key frames to move the object in a straight path.  Then create a circle at the end of the path and use 'follow path'.   However I can't get the timing right so that when one ends the other begins.  I tried this, but in graph view with the circle selected I don't see the options he describes.

create two follow paths.  one a straight line and the other a circle.  I was hopeful!!   The goal was to reduce influence from 1->0 at the end of the line, and bring up influence for the circle to "pass it over".   Fail.  I am unable to automate the influence function.  I move the frame, I try to reduce influence before setting keyframe.. but every time I reduce influence it moves my object back to the start of the path.  I guess I am messing this step up.

any help appreciated.

Would you mind explaining under 2. which options you don't see? The sidebar panel? He hits 'N' to bring it up as he says in the video. Or which options do you mean?

All three of your options are reasonable and doable; any problems you're having with them can be addressed.  However, the first technique you've tried is probably the simplest, and the only hard part here is, how to connect a straight section to a circle without screwing up the circle.  Let's see how we can do that:

Start by creating a bezier circle and entering edit on it.  Anything we do to this curve, we'll be doing in edit mode; that will leave our curve untransformed, appropriate for intuitive behavior on a follow path constraint from another object that is untransformed.

Select all curve controls + handles and set the handle type of these handles to "free".  This will allow us to add and disconnect segments without changing the curvature of unaltered segments.

Toggle cyclic on the curve.  A path has a beginning and end.  When you toggle cyclic, you will see that we lose a segment (no worries, it's easy to get back), but because we have set our handles to free type, the curvature doesn't change:

I've given my curve a bit of bevel depth so we can see what we're doing better.

To make a straight section, we can switch to "normal" orientation, then select a control on one end or the other, and extrude it.  To extrude it, type 'e' then 'z' then move your mouse to constrain the extrusion to the normal Z axis-- which in the case of a curve control, means the direction of the curve's tangent:

We only have 3/4ths of a circle.  Let's say that we want to do 540 degrees to come back out the way we came in a straight line.  That should demonstrate what we need to do for most situations.
To create additional sections, we'll start by selecting and duplicating controls.  Don't worry if they're joined or not.  I'll just duplicate my entire circle and then move it up one Z unit (via snap to increment), so that we can see what we're doing:

Now let's join two segments, by selecting two controls and 'f' to connect them, and delete a control on the end:

We can extrude the end of the path in the same way we did the beginning, then move our section back down a single unit in Z, since we no longer need to see what we're doing:

Of course, we can edit this curvature however we'd like.  It's safe to use "aligned" handle types, but the default "automatic" will probably change the curvature in ways you dislike.  So long as we do basic operations on our entire curve, all of its controls and handles together, we'll maintain this same curvature.  We can scale it up; we can scale it up in a single axis to make an ellipsoid; we can rotate the entire thing about its center, perhaps if we wanted our intro and exit lines to be at an angle to our world axes.

One possibility to get your first version correct or the circle more round than your lasso version:

Add a Bézier Circle and in Edit View select the bottom control point when viewing from top down onto the circle.

Then hit E, X to extrude the point on the X axis.

This seems to mess up the circle a lot because it is still cyclic and the new point is connected in both directions. To fix this, go to the Curve menu and choose Toggle Cyclic. You could also press Alt+C as long as you have any point selected.

Since the bottom point of the circle was the end point of the curve and it is no longer cyclic, the new point is no longer connected in both directions.

Now in order to fix the circle back to its original shape, select one of the two points at the bottom of the circle (you can see only one because they are in the same place). Let's say you grab the end point - the one with handles going from top left to bottom right as in the following screenshot:

With this point select, press R to rotate it, type '-45' and hit Enter to confirm the rotation.

Now select the other point in this location, the one with the handles from top right to bottom left, with the latter being longer than the other.

Rotate it half as much as the first point in the opposite direction, i.e. press R, type '22.5' and hit Enter.

Now the circle is back in its original shape. The control point you have extruded in X direction can be moved further out if you need a longer path to follow.


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Issues with rigging pulling on the wrong vertexes, even though they aren't bonded to the bone
I am trying to model and sculpt a medium poly character that has a fully rigged body and clothes. I am having this issue though. The mesh is properly parented and the weights were assigned with a data transfer from the body. I have tried to clean up the weights as much as possible but I'm still getting this issue where the rig will pull on faces that aren't even painted for that bone. The back faces of the hoodie are being pulled through the front faces and im not sure why because they are completely blue for every bone. I am pulling out my hair because of this problem, can anyone help me?

In edit mode if you select one vertex you can read its weights assignements in the "N" properties panel, vertex weights tab, so to understand which are the uncorrect assignements. Be aware that if a vertex has weights assigements to one vertex group/bone only it will follow that bone rigidly, even if the weight is 0.0001 (and looks blue in weight paint mode).
In weight paint mode you can also go to viewport overlays and change zero weights from "None" to "Active"  to better separate the black vertices (no weight) from blue vertices (some weight).


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Rig really Laggy
Im working on making 2 fully rigged human models. The second model has even more polygons,(100k for this one and 220k for the second one) and for some reason this one is significantly more laggy than the other one when posing. They are both using multiple multiresolution modifiers so I was thinkint it was that but honesty im not sure what it is as of this moment

Any help would be appreciated!

Base vert count doesn't matter.  Vert count going into armature matters.  This is 100k verts base, and multi-res makes more.  2) Is that particle hair?  That's slow.  3) Armature performance is number of vertex-influences-- a vert with 6 deforming weights takes three times as long to pose as a vert with 2.  4) Can't really begin to give definitive answers without files.


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How can I play object keyframes at the press of a button?
I want to make a PowerPoint presentation using Blender.
My idea is to have a camera that moves to the next "slide" when you press a button.
At this new slide you can play a short animation by pressing the button again.
And perhaps there's even a constant animation looping in the background.
Is this possible in Blender?

Yes it is possible with Blender

you can use this script:
import bpy

ob = bpy.data.objects['Next']

print("ob is",ob.name)

def object_selected_callback(ob):
    # Do something here
    print("object active ", bpy.context.active_object.name)

    if bpy.context.active_object.name == "Next":

        cam = bpy.data.objects["Camera"]
        cam.location.x = 21.3

    if bpy.context.active_object.name == "Back":

        cam = bpy.data.objects["Camera"]
        cam.location.x = 0

def subscribe_to_cube_loc_change(ob):

    print("called")

    if ob.type != 'MESH':
        return

    subscribe_to = bpy.types.LayerObjects, "active"
    bpy.msgbus.subscribe_rna(
        key = subscribe_to,
        owner = ob,
        args = (ob,),
        notify = object_selected_callback,
        )

subscribe_to_cube_loc_change(ob)

which e.g. moves the camera (of course you can extend this so that the cam is animated), if you press on these "buttons" (meshes/cubes), which have to be called "Next" and "Back".
Run the script and you get something like this:

UPDATE
and here is an idea how you could even animate it:
import bpy

ob = bpy.data.objects['Next']

print("ob is",ob.name)

def object_selected_callback(ob):
    # Do something here
    print("object active ", bpy.context.active_object.name)

    if bpy.context.active_object.name == "Next":

        cam = bpy.data.objects["Camera"]
        cam.location.x = 21.3

    if bpy.context.active_object.name == "Back":

#        cam = bpy.data.objects["Camera"]
#        cam.location.x = 0

        bpy.context.scene.frame_current = 100
        bpy.ops.screen.animation_play()

def subscribe_to_cube_loc_change(ob):

    print("called")

    if ob.type != 'MESH':
        return

    subscribe_to = bpy.types.LayerObjects, "active"
    bpy.msgbus.subscribe_rna(
        key = subscribe_to,
        owner = ob,
        args = (ob,),
        notify = object_selected_callback,
        )

subscribe_to_cube_loc_change(ob)

def my_handler(scene):

    paus=200

    print("Frame Change", scene.frame_current)
    if bpy.context.scene.frame_current ==paus-1:

        bpy.ops.screen.animation_cancel()
        bpy.context.scene.frame_current = paus

#remove all handlers
for i in range( len( bpy.app.handlers.frame_change_pre ) ):
        bpy.app.handlers.frame_change_pre.pop()

#append handler
bpy.app.handlers.frame_change_pre.append(my_handler)

result:


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smoothly connect two meshes at a vertex - smooth transition between objects
I am trying to connect two meshes together. The connection is a single vertex. So:
Mesh>Merge>ByDistance

The problem occurs when I add the Solidify modifier (Simple/Thickness 0.3/Offset 0). The point where the objects meet looks pinched. I also need it to have some width (say 0.5mm).

I have tried adding a few vertices to widen the connection point:

and it actually looked worse:

Can someone please help me figure this out? How can I have a smooth wide transition between two shapes connected at one point.
Thank you very much in advance.

So, I found an answer that satisfies what I was trying to do. Thank you very much @josh and all of you guys. (For some reason, the moderator deleted my earlier post saying it wasn't the answer to my very own question). In any case, here it is again.
I created a face where two vertecies meet:

After adding modifiers, mirror / merge, the final result looks like what I had in mind:

Thank you all very much.

Your first attempt is uncorrect: as points have no dimensions the mesh is not "Manifold", it can't exist in real life and solidify modifier can't create a proper solid from a single point.
The second version has an ugly "pole": a single vertex with more than 5 edges, which should be always avoided, expecially in theese areas of heavy curvature, and triangles and poligons with more than 4 vertices, avoid them also.
The solution is aim to a all quads topology with smooth transitions and no poles with more than 5 edges.
After creating the correct topology use "Smooth vertices" function and proportional editing to adjust the shape.

I'd say that heavy curvature is a problem, but not the single vertex itself... since Solidify doesn't have to generate a thickness from a single vertex which "can't exist in real life", the vertex is an edge point of a face (or two in this case), also non-quads are not a problem in general for the Solidify. Here I have tris, quads, n-gons and a single vertex connection between two faces: Solidify example No problem for the modifier. So I guess the heavy curvature is the main reason (if there are no double verts or anything else).

Josh and Gordon thank you both very much. I learned so much by reading your comments. I started learning Blender 4 weeks ago (come from engineering/Solid-Works background). Then it made sense, in Finite Element Analysis, a single vertex creates a singularity in the model/result. I will pos the final result to the bottom of this thread. Thank you both very much for taking the time and helping me out.

@GordonBrinkmann Kind of.  Apply your solidify modifier, then select non manifold.  After the solidify, the vert is actually a part of 6 faces-- and is part of an edge that connects 4 different faces, a major non-manifold no-no, even though Blender often tries its best to let us get away with that kind of stuff.  Here, also, notice that Aydin's solidify is followed up with a subdivision modifier, and that's an essential part of the problem here.  It's not that a 6-pole or non-quads are so bad for solidify, they're fine; but they aren't going to do CC subdivision the way most people want.

@Nathan Yes sure, you're correct. I didn't say it would be manifold... you just started off saying Solidify couldn't handle this. As you explain yourself it's more the Subdivision Surface and curvature which make it look weird. So everything's fine with your answer

@GordonBrinkmann It's not my answer :)


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Math Function Mesh
Could someone help me understand how to enter an X,Y,Z equation in Math Function Add on?
Here is a sample equation:
Cos(x)+Cos(y)+Cos(z) = 0
range -pi to pi
Thank you very much :)

Some help on how it looks
https://www.mathworks.com/matlabcentral/answers/636320-how-to-plot-cos-x-cos-y-cos-z-0
How to use the add-on in Blender
https://youtu.be/JdoFjxu605c
You may also want to try using geometry nodes will allow you to vary parameters in multiple ways.
Using Geometry Nodes to create and plot equations / functions
Another way to add the equation using the math nodes add-on. Math Formula addon v1.2.0 https://youtube.com/watch?v=II_0Ep1z-Ks
Also could use Animation Nodes (but takes a bit of learning)
How to create explicit (parametric) functions in animation node?
Also if the equation is complex here's a way to import it into blender https://youtu.be/rd7TTVYnz3c

Rick, thank you very much for taking the time and answering my question. Of all options, personally,  I prefer math nodes add on. It is worth going through the learning curve and all. Thank you again.

Your very welcome the members here have helped me tremendously, so when I can help I try to give back as much as possible.


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Blender 3.0.1 exports wrong Metallic/Roughness Map when exporting glTF2.0
I am new to Blender and am recently learning how to use it. I add a plane to the scene and applied base color to the Principled BSDF Node from an ImageTexture node. I also generated the grayscale of the texture using Paint.NET and applied the grayscale to roughness and metallic properties after some transforms. It looked nice inside Blender, but after I exported it to the glTF 2.0 file, it messes up, and the model seems to have a wrong roughness map applied to it. I also exported a .gltf file and textures separately, only to find that the G and B channel of the output roughness/metallic texture has completely the same values, which goes against the glTF2.0 specification. The spec states that metallic value should be stored in the B channel and roughness value should be stored in the G channel, and it seems that the roughness channel is overwritten by metallic values. Is this a problem in the Blender glTF export module or I have done something wrong?
This is how I configured my shading nodes:

And this is the texture output of the glTF files(I compressed it as the original image exceeds the 2Mb limit)

Generally exporters can handle only certain fixed node graphs. The only node setups the glTF exporter recognizes for metallic/roughness (besides a constant) are:

A texture connected to Metallic/Roughness socket through a Separate RGB node. You can use whichever of the R, G or B channels you like. If your texture is grayscale you can skip the Separate RGB node and connect the Color straight to the metallic.

Same as above but with a Math node set to Multiply before the socket. This is exported as a glTF metallicFactor.
All other nodes are ignored.

So in your case, you can fix the metallic path by replacing the Map Range node with a Multiply by 0.3 node that does the same thing. But the Invert and Map Range on the roughness path cannot be exported; you'll have to prepare a separate roughness texture to use.


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Rigging issue, disconnecting body parts
not sure where to ask this to be honest, reddit pretty much takes down everything i type. But anyways, im trying to rig a model right. Humanoid. The model was a human i cut up to fit inside of a suit i made.
The suit isn't the issue, because the human by itself had the same issue, im going to be attempting to rig it agian in a few days and would love a head-start on how to fix this issue once and for all.
I try to look at videos online, but none cover this exact issue. In the past, I've tried weight painting, clear parents, assigning automatic weights, assigning troublesome parts to vertex groups and no matter what i do, the arms and head always disconnect from the rest of the rig after ARP creates it.
I don't have an image of the bones on hand, but i can easily replicate the problem and get them. I know for a fact the entire rig is connected, im using a blender Add-on called auto rig pro. Mixamo can rig the model with no issue but i need it from the add-on for my use case.
Any ideas would be appreciated.

Simply put, there is a hole in your mesh, and right now it is not rigged/weighted so as to not pull apart from the bone deformation.
You have two options:

Fill in the hole. How you should do this depends on what kind of hole it is. If, as I am guessing, the arm simply an open-ended tube intersecting the body, a Boolean operation with some smoothing afterward would probably work.
Make sure every vertice involved with the hole has the exact same weighting, so that if part of the hole moves, the rest moves with it, and it stays hidden. This approach is only recommended for situations where a hole really helps with modeling, and where the resulting block of deformation won’t look weird,

Thanks, I'm gonna try some of this stuff and post updates in the morning!


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Changing Geometry Nodes Modifier Input with Python
I'm a novice with Python (at best) and fairly new to Blender, so apologies in advance for the question. Nonetheless, I have been searching all similar Qs/As online for hours and cannot find the solution.
I have a scene with a plane that is displaced in a ripple pattern according to the proximity of another object (using the geometry node modifier set-up from this excellent post: Sinusoidal damping from distance object (Wave function - Geometry Nodes)). I can copy a second geometry node modifier on the plane, create a ripple pattern with a different object, and generate an interference pattern from the two, which works great. Three object version here:

The problem is that I have several hundred objects, and doing this by hand is not viable. Using a simple script I can copy and rename as many modifiers as I want, however, I cannot work out how the change the object reference. Essentially, in reference to the above image, I just need to know how to change the "Origin Object" from "Icosphere.002" to "Icosphere.003", or whatever object I want.
It looks like it should be so simple, using the following where "Input_6" is the "Origin Object" input.
bpy.context.object.modifiers["GeometryNodes"].Input_6 = "Icosphere.003"

But this returns the error:
AttributeError: 'NodesModifier' object has no attribute 'Input_6'

I can see many others have encountered this issue online, but I cannot find/do not understand the workaround. Can anyone help? Thanks!

The correct syntax is:
bpy.context.object.modifiers["GeometryNodes"]["Input_6"] = bpy.data.objects["Icosphere.003"]

You can see it suggested when you type in console:
C.object.modifiers["GeometryNodes"]

and press Tab.

Thank you so much! Interestingly, when I used the correct syntax the modifier stack only updated AFTER I clicked off the object, and back on again. This was the underlying issue, as I had been using the correct syntax previously and copied it incorrectly above.

@QuarantinedMarsh you can use obj.data.update() after you've changed the modifier to show the changes!


text:
How to disable modifier calculations while in edit mode?
I'm working in a project with many boolean modifiers, so the performance when I edit a mesh (that is affected or affecting by all these modifiers) completely freezes my computer for several seconds every time I drag anything.
I noticed that disabling the viewport realtime toggle in the modifiers do not actually disable realtime calculations,
So the only workaround I found is going modifier by modifier removing the target object, making edits to the mesh, and then re-associate all the modifier target objects. Which as you may guess it is not very user friendly nor time efficient.
Is there a way to make the modifiers only to recalculate on exiting the edit more? or to actually disable modifiers temporally?
Thanks!

In a simple situation, disabling viewport display of the modifier does disable calculation.  I tested this, in 3.0, by testing with a couple of subdivided UV spheres with boolean difference.  There could be some details specific to your situation that change that-- but then, we'd need to know those details.

I'm still in 2.x, I will try 3.0.
Do you know which kind of "situations"?
thanks

I'm now in 3.0.1, realtime-disabled bool modifiers are still being recalculated in realtime in edit mode :'(

Then like I said, there could be some details specific your situation that change that, but we'd need to know those details.

Thanks for your time @Nathan, I created a new project, all preferences are fresh from 3.0, I create 2 spheres, apply subdivision to both (enough to stress the cpu), add bool modifier, go into edit mode, drag vert, dragging is slow (bool being recalculated), then for comparison disable bool realtime and is dragging still slow, and finally with bool target removed (so it is modifier is actually skipped) dragging is back to normal. This kinda tell that modifier realtime toggle does not really stop calculations, but just do not draw them in the viewport? Is this expected behaviour or a bug?

The dragging is probably not slow because of your boolean, but because of live subdivision.  Check out https://pasteall.org/blend/a366014b74954ef09a9e1ae1f661b3a9, which has an animation, incl. animated viewport visibility of a boolean, which should make the performance difference clear.  It's set to a fast solver, but it's the same with exact solver (only slower, while the boolean is in operation.)

But in future, just link a file.  When people are asking questions, it's almost always because there's something they don't understand.  The problem is, when they don't understand a problem, they can't distinguish between details relevant to that problem and details that aren't.  Linking a file lets people who can distinguish rapidly identify the cause.

Submitting a project file would be tricky because getting to the point in which the cpu struggles would vary depending on the pc. In any case I found an alternative workaround by using "hide in viewport" checkmark in the outliner, so it is equivalent to actually disabling all the modifiers of the problematic object while working in another one.


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How do I modify a procedural mud material from Blender 2.79 to 3.3?
I'm following this tutorial: https://www.youtube.com/watch?v=vfc3LwNI_aY
As can be read in the comments, the setup doesn't work for recent versions of Blender, and I'd be incredibly grateful for advise on how to do something similar in 3.3? The entire node tree can be viewed in two parts from 6.31 min and forward (I've only attached a picture of half the node tree!).
5.18 in a noise texture + a voronoi texture are exchanged to an image texture too quickly for me to understand what type of image it is — but that shouldn't have anything to do with the problems I get. My results are differing long before that and his result is good also with noise + voronoi.

The linked video of the question is not so much a tutorial as an experiment. It's hard to follow because the values get changed all the time and there is an image texture used that is not available for download. And Blender 2.79 is used. So you have to make some of the settings with a sense of proportion. But you can have something similar in Blender 3.3 ...
A delicious mud ball!

In the video, Blender 2.79 is used and since Blender 2.80 the GUI has changed. So everything looks a bit different. Also, in Blender 2.81 a few nodes have been changed, especially the Voronoi node. But you can replicate them in Blender 2.81+.
Related links:

video: When You Update Blender... (Old Procedural Texture Transfer)
video: Blender 2.81 : Procedural Shader Nodes & Voronoi Updates
question: How to get old Mapping and Voronoi nodes into Blender 2.82?

So, for the mud ball in Blender 3.3 you need the following ...

the default cube with a level 6 Subdivision Surface modifier to have enough geometry for the displacement
Cycles because the displacement of the material only works in Cycles. In Eevee, you could use the Displacement modifier with a baked texture.
in the material settings, set Settings > Surface > Displacement to Displacement and Bump to make the displacement work
in the Shader Editor, you need to add a Displacement node and use its Height value. Use a low value like 0.050 for the Scale input
a replacement for the Voronoi (Intensity) node is a Voronoi node plus a Math (Power) node to multiply the Distance value with itself.
because the 2-meter default cube is used we need to have a Mapping node to scale the texture a bit (Scale group). If you have a smaller object then you need to adjust these values and the Scale input of the Displacement node.

All other nodes and their values are the same as shown in the video before the final optimization, except the Image Texture for the Bump in the Water group. Here a Noise and Voronoi node are used as shown earlier in the video. I did not compare the values shown in the video with the final optimization and skipped it because the result looked nice to me.
Have fun with the mud!


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Solidify outline not working correctly
So I tried to set up an outline, however, this happened. Ignore the bits with clothes, but the rest (head, hair and right arm) don't have the outline. How do I fix this?

It seems you have multiple modifiers. Have you tried changing their orders ?
Please add your blend file so we can better understand the behavior you have in the file

Sure! My wifi's terrible so I have actually been trying to upload it for a while. Also, yes I have tried changing the orders of the modifiers.

i have no idea how you made your "outline", but if you made it via grease pencil, be aware that the outline will only be painted correctly if you look through your camera.

@Pineapple, depending on the way you create your outline effects, if it is with a mesh, have you try reverting or recomputing normals?

@B.Pader Thanks so much! this worked perfectly, I can't believe I didn't think about this sooner heh.


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Can't see blender bake tab
Under render properties I can't see the bake tab. I've tried loading factory settings and OptiX is not enabled in preferences, is there any way to fix this?

Maybe you are in Eevee? In that case, switch to Cycles

Thanks! That was the problem

You can't bake in Eevee, you need to switch from Eevee to Cycles.


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Fly mode - mouse navigation does not work (2.79/Ubuntu)
I have a problem with the fly mode on ubuntu and Blender 2.79. Everything was working perfectly a few hours ago, and suddenly the navigation control is not responding at all. The forward and backward movements, acceleration and deceleration still work fine. Only the mouse no longer allows you to change the direction: the cursor moves freely and the small target that usually appears in the centre of the screen has disappeared.
I have reloaded the factory settings, reinstalled the software, but nothing to do... I also found a thread with the same problem, but unfortunately the solution doesn't work for me. Does anyone have a solution?
Thank you very much!


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My environment texture is not displaying

I have enable equirectangular, pressed 5, not sure why this is happening. Please help.

IN node editor In the properties you don't have source file. click the reload (turning arrow)

If not load the above the source file click the cross button to delete the properties and in the environment load the image

Adding the image to the source file actually worked! thank you so much!


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Editing collada file with built-in UVs
I recently purchased some basic terrain assets, and when I import them to Unity, they look nicely textured.

My plan is to create several variations on this terrain (creating paths etc.) and I figured it would be a matter of importing them into Blender, then painting it, or exporting the UVs and creating a texture in Photoshop or something.
However, when I import the .dae file into Blender, all I get is a grey, untextured version of the mesh.  I can see there's a UV map listed in the file, but I have no idea how I'd go about accessing it or editing it.
Anyone have any suggestions?

Look Honestly because i would post a comment but because i don't have enough rep i have to answer, but with blender try to go into the material properties and hopefully if you got the mesh of the internet it should have different materials, just change those separate materials and modify them to suit you since they should of been already made from the owner.

As seen above, there should be multiple textures for that one model.
I hope this helps and i don't quite know if i completely answered your question. If you don't see the extra materials i would say it wasn't made to be compatible with blender.

Hey man, I think you really helped crack this!  I'll post a more complete answer below, but I wanted to say thanks!

the guy above really helped me with this, but I just wanted to flesh out what all it was (in case anyone has a similar issue).
Sure enough, as he said, there were two materials listed in the material properties window.

However it was still frustrating because the image itself still looked to be one uniform texture.  However, if you modify those materials...

Sure enough, a pattern starts to emerge.  I realize what (I think) these people are doing is setting the materials in Blender, but doing the actual coloring in Unity with a shader.
So I believe to modify one of these meshes, I'd just need to assign different materials to the different faces, and even though they wouldn't look different in Blender, in Unity they should show up as the proper color.  I'm not sure how exactly they're making the conversion from material to color (if let's say I wanted to create my own material with its own color properties) but I think this is at least a good jumping off point.

Hmm actually this didn't work... If I import it from Blender it comes in with that hot pink color.  If I try to replace it with the existing material in the project, it resets the texture to how it was before I put it in Blender... somehow that information of what material goes where is embedded somewhere else...


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Would it be possible to write an addon that allows processing rendering over an Android smartphone in parallel with the desktop computer?
We are engineering students studying management and innovation.
We would like to use our smartphone’s processing power to reduce the rendering time of a Blender project, a short movie for example (and maybe later other software like Premiere Pro, code compiler, etc…).
Our idea is that a lot of people have a high-end smartphone, but a modest computer.
When rendering, we think that we could use an Android smartphone’s processing power to help reducing rendering time.
There would be an application running on the Android smartphone, and an addon in Blender that changes the way Blender manages frame rendering. Some frames to be processed would be sent to the smartphone’s CPU (or GPU ?). After processing, frames would be sent back to the computer and reassembled to the ones processed by the computer. So there would be a parallel rendering between the computer and the smartphone.
More generally, we would like to be able to render a Blender project using multiple devices and OSes.
Have you heard about similar projects, and do you think it would be feasible (even if it would be hard) ?
Thank you in advance

Transmission between computer and smartphone could be done over network  or cable (for lesser latency)

The idea is pointless, did you ever rendered a scene on any phone? You are wasting energy and you'll need to charge the battery before even 1 single frame is finished. Innovative would be finding a way to save energy.

Android version of Blender https://www.blendernation.com/2015/02/12/using-blender-for-android/ just be aware it has not been updated for 4+ years

About energy, the phone would be plugged to the PC, so battery charging isn't really a problem. When looking to IGP specs compared to high-end smartphone's GPU, I can see that Adreno 540 and 630 in Snapdragon 820-845 has more or equal GFLOPS (567-737 GFLOPS) compared to most Intel IGPs (Intel HD Graphics 5xx and 6xx) in laptop (300-500 GFLOPS). Maybe it is possible to use raw GPU processing power of the smartphone for rendering ?

If you still believe that's a thing, there is an android build of ffmpeg to play with - you could encode some raw frames to prores or something and you'll see that this already takes a lot of time. GPU won't drive it anywhere (needs to be implemented) - AMD developers writing code for blender since 2-3 years to support cycles (see blenders history). Hope that helps.

Thank you for your comment, we are investigating about the use of smartphone's GPU through your ideas.


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Fairy's wings material
How can i achieve a fairy's wings material similar to this one when they glow (i'm using cycles).Thank you

How far have you got? The solution will be multi layered. Is the result animated of still?

@rob 1 It's still.I'm just a bit confused on what should i do.

If the final image is not animated then you can do all sorts of things to fake cool lighting and reflections. I would break the task down. Get the model right and add transparency. Then look at the input sharpness node. You can mix gradients and other patterns to create all the affects and finally use the compositor to add the glare. Good luck.

There are a few ways this can be done.
The way I would go with is to draw the pattern of the wings in Photoshop/Gimp and use that as a bump map on a glass shader.
Another way that I did above is to make a base shape for your wing.
Subdivide it 4 or 5 times, apply it, then go into sculpting mode and sculpt the wing pattern (better than I did).
Then use the node set up above.
You can just use a glass shader with an emission shader in the volume, I used 3 different colors for the emission shader and mixed them with a noise texture to break up the colors.
For the glass shader I added a transparent with a layer weight node as a mix factor just so I can hide the glass and make it a little more magical.
If you use the node set up above, play with the noise texture settings and the colorramp flags to clamp what you see.
The multiply (math) node is there just to make the emission brighter or darker.
You can play with the roughness value of the glass shader too, It looks like here wings are a little bit frosted.

comments cleared to prevent a flame war.


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Align multiple objects on same plan
I was looking for a quick way to align multiple objects on the same plan.
I made an architecture with lots of cleats and need to rotate all of them so they are aligned straight. Aligning them one by one would take way too much time..

I'd like to get from here :

to here :

Rotation was reset to 0 in edit mode while modeling so the default rotate position is the position they are currently in..

Does anybody have a solution ? :)

General Idea
The built-in function mathutils.geometry.box_fit_2d could help you with that.

from left to right: original, without correction, with correction
box_fit_2d is a function that calculates the angle by which two-dimensional coordinates have to be rotated to best fit an axis-aligned rectangle.
For every object you take a list of all vertices and project them to a plane perpendicular to the axis around which you want to rotate. Then you convert these projected vertices' coordinates, which are still three-dimensional, into two-dimensional coordinates so that box_fit_2d accepts them. If you rotate around one of the main axes then this is simply a matter of dropping one of the coordinates. E.g. vertex [x, y, z] becomes [y, z] when you rotate around the x axis.
This two-dimensional vector is passed to the function which returns the angle that you can use to rotate the object.
As far as I'm aware, box_fit_2d doesn't do checks about which side is longer. So, if you want the bars to point in the same direction, you have to do an additional check, e.g. whether the range of y values of the rotated object's vertices is higher than the range of z values, like it's the case for the box in front in the image in the middle. And if that's the case increase the rotation angle by 90 degrees.
Implementation
I generally use the add-on Animation Nodes for this kind of calculation, but this method could be done with a Python script in Blender without any additional tools.
The naïve Animation Nodes node tree that was used to generate the middle image is pictured below. Note that you have to would have to list the module mathutils in the advanced node settings for the expression node, if you want to use the module in an expression.

The correction that would increase the rotational angle by another 90 degrees when the object is horizontally aligned was wired like below:


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Scene ran fine, then updated windows, now playback is VERY slow
So, I was animating a scene, not too complex, and playback was fine, then I found out my windows was outdated so I clicked update and restart, it then took 5 attempts to get back into the computer as the CPU would malfunction, and when I did, the same scene(no changes) couldn't even get past 18 fps.  Nothing I've tried works, I updated my graphics drivers and everything.
System Specs:
Ryzen 5 1600
16GB Ram(2400)
GTX 1070(non-ti variant)
MSI B350M PRO-VDH Motherboard
Stock Cooler
EVGA 80+ Gold Supernova G2 850W PSU
1TB WD Red Pro Hard Drive(7200 rpm 64MB Cache)
Does anyone have a clue as to what happened and more importantly, how to fix it?
P.S. All other cases of this happening were because of an underpowered system.  This time, it was working fine and now it isn't.

This last Windows update was the last straw for me... same problem.. but I was lucky: mine was fixed by driver reinstall.. I'm now engaged in the research to return to where I started: Unix... well... nowadays... Linux.

I tried it, it didn't seem to fix the issue.


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Layout bugged after opening .blend file on windows instead of mac
Multiple options overlapping so its hard to press some buttons.
all i did was sending the .blend file over discord from a mac to windows and this is how some places look.

How do i fix this?

https://blender.stackexchange.com/a/2152/110840 - check the bottom section of this answer for newer versions

@AllenSimpson I don't think that helps in this case.  3.0 seems to have a bug where it is overlapping things in the top left of the 3D Viewport.

It didnt seem to help no...


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Sculpture turning black. (most likely beginner problem)
I recently starting using blender and I have been encountering several problems. i usually find the solutions on the Internet, but this time I havent found anything that helped me.
After working for about 20 minutes of a face my mesh suddenly turned black. When I tried to change the mesh color it said it was white (eventhough it was black)  and nothing happend when I tried to change it it. How it looks in Edit/sculpture mode in shown in the pictures below. In objektive mode it looks the same as in sculpture mode.
Please help me change back the mesh to white.

I guess you have masked your whole object. Press ALT + M in sculptmode to clear the mask.

Your Viewport Shading is on Wireframe (upper right hand corner of the 3D View window, the four sphere graphic buttons, the first one is highlited).  Sculpting usually requires a dense mesh, so Wireframe, which shows all the edges of all the polygon faces, will make that black unless it's selected, then it'll be orange.
For sculpting you probably want your Viewport Shading on Solid (upper right hand corner of the 3D View window, the four sphere graphics, the second one is Solid).  Once you've done that click the carat down-arrow symbol to the right of the sphere graphic buttons, you'll get more options to show the surface of your model to best advantage while sculpting.
You also have X-Ray enabled (the button with the cube graphic to the left of the Viewport Shading buttons).  This shows the normally hidden areas of your mesh, which in Wireframe will make it look even denser.

Thank you for the help! It worked!


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How to recalculate a skeleton's pose (all PoseBone matrices) via python without a full scene update?
I'm working on a script to do some retargeting of an animation library to a new figure, and I've encountered a performance issue I don't know how to optimize away easily. My script loops through an animation using bpy.context.scene.frame_set(frame), and makes changes to the matrix and matrix_basis properties of a figure's PoseBones. There is one iterative step in the algorithm where I want to update a PoseBone, and then have the full pose recalculated so that the matrices of bones that are descendents reflect the change.
Calling bpy.context.view_layer.update() is suggested in response to a number of similar questions, but this updates a lot more than I need it to, with a crippling execution time cost when there is a high-resolution figure using the affected Armature.
One thought I had was to temporarily remove the Armature modifier at the start of the script, and replace it at the end, but before I try workarounds like this I wanted to ask if there is simply an API call I can't find to recalculate only the pose matrices of the bones of an Armature without forcing Blender to update all the affected meshes?


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Why Does my Keyframe Path Change?
Im following CG cookies bouncing ball tutorial. I seem to understand everything thats being said except for one thing.
They're talking about deleting unnecessary keyframes on the X, and all we need is the Start point, its First Touch Point, and the End Point, and the rest of the keyframes can be deleted on the X.
The thing is when I delete my keyframes, my path totally changes, and I don't understand why at all, I thought I was following along exactly to the video. Whats going wrong?

Its strange because I've don't this tutorial successfully before, and was only doing it again as a refresher but now it seems to be screwing up.

Ok for some reason when I delete my keyframes my graph seems to curve upward, I can add more pictures if needed.

never mind I guess my path was supposed to change and I just had to manipulate the curves. i didn't realize it would change so much though.


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How can I create a new object in the Outliner?
How can I create a new object in the Outliner?
I'm using Blender for the first time and im watching this tutorial video.
https://www.youtube.com/watch?v=v_X9v29i-Iw
As you can see in 1:16 min in the video, the guy adds a cylinder.
If I add this cylinder, it doesn't appear as a new object in the outliner.
It's a problem because I used the Subdivision Surface tool on the body
The cylinder that I add there has the subdivision surface tool as well then... and it's not a cylinder anymore...
If I want to remove the subdivision tool, the body doesn't have it either then.

I have no idea what is a problem. It seems to me you are confused in terms.  For 99,9% Blender projects you will never need more than one scene. In this tutorial he just insert cylinder. You can do it by Shift+A - Mesh - Cylinder in viewport.

BTW - this is not very good way how to start learn Blender. Go for something easy and learn basics first :-)

If I add the cylinder it's just not a cylinder you know ._. And in his video, the cylinder appears under the other object in the outliner.
In my outliner, there appears nothing.. that's why i thought it has something to do with the scene.. xd
Yeh i know its not a very good way to start with Blender - but i already have the whole body! °-° And I want to finish it >-<

Probably if added object isn't shown in the Outliner the hierarchy in it is collapsed (hidden). Show a screenshot of your Outliner window along with viewport and Properties editor windows. Cylinder with Subsurf modifier remains to be cylinder - just as any object. I think you are mixing different terms and workflows, look into basic tutorials on Blender interface first.

Heyy!! I solved my problem - I don't exactly know how but it was something with the selecting object. Thank ya all! >-< After this project, I'll look into the basics.. x-x

You have to be careful in witch mode you add a new object. If you are in object mode you add the new mesh as its own object and you can see it in the outliner as its own item with its own modifiers, etc. but if you are in edit mode inside another object and you add the new mesh in edit mode it becomes part of the geometry of the object you are in edit mode of sharing that objects texture, modifiers, etc.

@Shallty Don't forget to accept as an answer if it helped you :D


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How to make animation like this using array?
How can I make animation like this using array without deforming the shape of the ball? I already tried to make it using array and curve but the balls are deforming when I make the 2nd layer of the curve.
(sorry for my bad english)

editing my own post since I can't upvote / comment on the other post by cegaton! (use his answer! it's 10000x better! I didn't know dupliframes existed! :D )

hmm, at first, I tried the curve modifier, but this does morph the shape as you specifically requested it shouldn't! (So it's probably the first thing you tried!)
There was another way I 'kinda' got the desired result, or at least, a method that could (with a bit of tweaking), result in the desired output / effect.
That is to turn your path into a mesh (Alt-C), and then apply a particle system to the resultant mesh (you can't make a path itself a particle system). Then you can set the system to:

emit from verts
turn of 'random' emission ordering (so they iterate through the verts)
set lifetime to long enough so that the 'snake' covers the path.

Lastly, to tweak this, you probably want to 'fix' the mesh that's drawn so that you get evenly spaced vertices (the one i made now was very crude & hand drawn though, using shift + clickdrag in edit mode on the path)

Tried it and it worked, but the other answer is more easy to use, but still thank you for answering


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UV mesh does not appear in UV editor in blender 2.8 but does in 2.79
as you can see in the below images, when I try to view the UV mesh in the UV editor In blender 2.79 It works perfectly, but when I open the exact same file in blender 2.8 It does not show up. I have already checked the "view" menu which only shows the options for "view" "mask" and "paint" and not "UV".

I have also tried this with a new object in a new file and that doesn't work either
Thanks for your help!

In 2.80 the Image and UV Editors are 2 different things.
Your screenshot is showing you have the Image Editor open.
Change to UV Editor to see the UV unwraps :


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A procedural asphalt material with inset stones
I'm trying to make a realistic looking asphalt texture, with the little stones of about 3 different colours set into it.
Here's what my current attempt looks like:

And here's my reference:

There are a few problems that I'd appreciate help with:

The stones are too rounded, I've tried adding more noise textures to add some distortion to them but nothing manages to look like the angular stones in the reference.
The stones are all one colour, but in the reference some are brown, some grey, some reddish. I could add some coloured voronoi to the result, but the result would have more than one colour per stone.

Can anyone offer some advice or tweaks? I've added the blend file here:

False-color:

Using the same Voronoi node for the rock/asphalt mask (rocks made rougher with noise) and rocks in three different colors may be closer to what you're going for.


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Exporting as VRM, getting error codes relating to materials?
I am using this addon:
https://github.com/saturday06/VRM_Addon_for_Blender
and have used it successfully before, but am getting an error code when I attempt to export it. I can't make heeads nor tails of the technical jargon- what exactly do I have to do in order to prep the model for export?
Report: Error
A Python: Traceback (most recent call last):
File "C:\User: Downloads blender-2.92.0-windows64\blender-2.92.0-windows64URM_Addon_for_Blender-release\io_scene_vrm exporter init_.py", line 55, in execute
bool(self.export_invisibles), bool(self.export_only_selections)
File "C:\User Downloads blender-2.92.0-windows64\blender-2.92.0-windows64\URM_Addon_for_Blender-release\io_scene_vrm exporteriglb_obj.py", line 58, in_init__
"INVOKE DEFAULT", show_successful message=False
File "C:\User: Downloads\blender-2.92.0-windows64\blender-2.92.0-windows6412.92\scripts modules\bpylops.py", line 130, in call
ret = _op_call(self.idname_py(), C_dict, kw, C_exec, C_undo)
RuntimeError: Error: Python: Traceback (most recent call last):
File "C:\User: Downloadsblender-2.92.0-windows64\blender-2.92.0-windows64\RM_Addon_for_Blender-release\io_scene_vrm editor validation.py", line 43, in invoke
context, self.errors, self.show_successful_message
File "C:\User: Downloads blender-2.92.0-windows64\blender-2.92.0-windows64 VRM_Addon_for_Blender-release\io_scene_vrm editor validation.py", line 248, in detect_errors_and_warnings
for node, material in search.shader nodes and materials(used materials):
File "C:\User: Downloadsblender-2.92.0-windows64\blender-2.92.0-windows64\VRM_Addon_for_Blender-release\io_scene_vrm editor search.py", line 11, in shader_nodes_and_materials
for mat in used materials
File "C: Users Downloads blender-2.92.0-windows64 blender-2.92.0-windows64\VRM Addon for Blender-release\io scene vrm editor search.py", line 12, in
if mat.node_tree is not None
AttributeError: 'NoneType' object has no attribute 'node_tree'
location: C:\User:
Downloads blender-2.92.0-windows64\blender-2.92.0-windows64\2.92\scripts modules bpylops.py:130
location: :-1

I've not used this AddOn before, but, purely in terms of the technical jargon, what the error message is saying is that it encountered a None material, and that None (representing the absence of a material, if you will) has no node_tree (a "node tree" being the computational way Blender materials represent shader nodes). Specifically, it looks like this line is failing, though I'm not sure off the top of my head what the "Surface" attribute refers to: https://github.com/saturday06/VRM_Addon_for_Blender/blob/95785c93de8899e8e33c6ad34a29e84fb9df2928/io_scene_vrm/editor/search.py#L12

It looks like used_materials is created here: https://github.com/saturday06/VRM_Addon_for_Blender/blob/95785c93de8899e8e33c6ad34a29e84fb9df2928/io_scene_vrm/editor/validation.py#L176 If you upload your .blend file, maybe someone can execute that for loop and try to determine why a None is being appended to this list, where only materials are expected

@NeverConvex sure thing- the model is saved here: https://drive.google.com/drive/u/1/folders/1KBVWdJMaK-qhEwVrsnKc0Iruil5iIR3C?ths=true  In the meantime I'll try looking through the materials and see if there is a part of the model that does not have a material, thank you for the response

I think I figured this problem out, but it took me a bit of digging. I've split this into a lengthy description of how I examined the problem, and then a brief description of how I believe @Halppls can fix it in their Blend file.
--Investigation/Explanation of Problem--
Following on my comments above, I ran this for loop (a slight modification of the one in the linked repo, focusing on the list that appears to contain a None value where a material is expected) in a Blender Scripting window:
>>> for mesh in [obj for obj in bpy.data.objects if obj.type == "MESH"]:
...             mesh_vertex_group_names = [g.name for g in mesh.vertex_groups]
...             for mat in mesh.data.materials:
...                 if mat is None:
...                     print(f"For {mesh}, got mat {mat}")

This printed:
For <bpy_struct, Object("Object.037")>, got mat None
For <bpy_struct, Object("Object.038")>, got mat None
For <bpy_struct, Object("Object.039")>, got mat None
For <bpy_struct, Object("Object.040")>, got mat None
For <bpy_struct, Object("Object.041")>, got mat None
For <bpy_struct, Object("Object.042")>, got mat None
... [ellipses mine; all objects between these two numbers were printed]
For <bpy_struct, Object("Object.067")>, got mat None
For <bpy_struct, Object("Object.068")>, got mat None
For <bpy_struct, Object("Object.069")>, got mat None

Selecting just Object.037 (which is the main, red part of the robot's body), I can verify that data.materials contains only the None material:
>>> [m for m in bpy.context.object.data.materials]
[None]

This is surprising, since Object.037, for example, clearly has RED set as its material. But, this is only true in the Materials sub-menu for Object -- i.e., it only has RED as a material linked to its object, not as a material linked to the data (meshes, curves, etc) making up the object. You can see this if you open this sub-menu:

Although you'll see that there is a material linked to the Object, switch that sub-menu to Data view, and you can see that there is only an empty materials slot on all of these objects. If we assign RED as a Data-linked material, now, then it looks like we get the behavior the AddOn expects:
>>> [m for m in bpy.context.active_object.data.materials]
[bpy.data.materials['RED']]

As an aside, this makes me wonder what the proper way to access Object-linked materials through the Python API is. It looks like this (which is not the way the VRM AddOn tries to access materials; it uses object.data.materials, which seems to only collect data-linked materials) kind of call may work, for accessing Object-linked materials:
>>> bpy.context.object.material_slots[0].material
bpy.data.materials['ORANGE']

More information on the distinction between Object and Data linked materials can be found in the relevant Blender docs:

Specifies whether the material is to be linked to the Object or to the Object Data.

The Link selector has two choices, Data and Object. These two menu choices determine whether the material is linked to the object or to the data, (e.g. a mesh or curve). The Data menu item determines that this material will be linked to the mesh’s data-block which is linked to the object’s data-block. The Object menu item determines that the material will be linked to the object’s data-block directly.

--Just The Solution--
I think you just need to go through each of objects numbered 37 to 69, go into the Materials tab, switch from Object to Data linked view, and assign the desired material(s). After this, the VRM AddOn shouldn't see None as a material on these objects any longer.

Holy cow, this is so much effort put forth into this answer! Thanks for going the extra mile to help! I'll get working on this and see if that solves all the issues. Many thanks, you are a wonderful person


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2.8 textures are messed up when rendered but fine in look dev
when I try to render this scene in cycles I end up with the textures not coming out properly:

It also has errors in Eevee but not as severe:
But it looks perfrctly normal when I do a viewport render in Look Dev
I have tried this in two different versions of 2.8 including the most recent version and one from the start of the year
the same problem has happend to me on most of my projects in 2.8
I assume that this is a bug but any help would be apreciated :)

I may be wrong, but I don't think you can use overlapping UV islands if you're using a normal map. Maybe try using a geometry node using Object or generated for the normal map? Also, make sure your sub-div modifer (if using one) that the viewpoint and render value is the same.

May be these object are duplicated and the doubles are hidden only in viewport but not in render.

Ah yes, that was it. thanks so much for telling me that, it has just saved me a lot of wasted time!


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How to speed up selected to active texture baking
At the moment I am doing a lot of texture baking heavy work at the moment and it has got to the point where this is the slowest part of my workflow.
I'm aware of the obvious things like texture and mesh resolution but I was wondering if there was something I'm overlooking, though this may not be the case.

If you don't want to bake the ligths, you can decrease the render samples to 1.

Please describe what your workflow is, so we can point out what may be wrong. It's hard to guess without more info.

I'm baking textures from a high poly photoscan mesh to a low poly retopologised mesh. there may be nothing I can do to speed it up due to the number of vertices involved but I thought there might be something I had overlooked.


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smooth shading error on a low poy model creating sharp edges
I have a low poly model with smooth shading enabled on all faces. unfortunately, when I go into rendered view, I see odd sharp lines on the edges and tris not previously seen in lookdev view:
Rendered view:
Edit mode:

Try recalculating normals ctrl+N in edit mode or merge vertices by distance also in edit mode I think alt+M for the merge

no, I tried that and it doesn't seem to work, so I'm not sure what's up. If it helps it was imported from instant meshes as an obj

Its probably due to lighting does it still persist when you move your light source around, and from the image of your node editor your normal map isn't applied yet.

Yes, the problem continues when the light source is moved and also when all the textures are applied, but the problem does seem to be reduced when I use a larger light source, though that is to be expected. I wonder if this might be a bug?

so it might be the "Terminator effect" (pixellisation effect on the border of the shadow)... to fix this you need to increase the size of your light (called angle in 2.8). I've heard it's a problem that should be fixed in some next versions of Blender.

Your low poly and high poly maybe rendering on top of each other. Check your render and view toggles in the Outliner.


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How to register a collection property to a custom property group
I would like to register a collection property for a list to a property group that I have already created.
Unfortunately, this doesn't seem to work:
bpy.types.Scene.my_group = PointerProperty(type=MyGroupClass)
bpy.types.Scene.my_group.my_list = CollectionProperty(type=MyListClass)

This could help tidy up my code by simply accessing the list through the property group, rather than just from the scene like normal. Is this possible?

define  the collection my_list as a member  of  the propertygroup. MyGroupClass

Yep, that's it, thanks!

Thanks to @batFINGER for the answer.
I just had to use this code instead, using the actual class name instead:
bpy.types.Scene.my_group = PointerProperty(type=MyGroupClass)
MyGroupClass.my_list = CollectionProperty(type=MyListClass)

well kinda, this is monkey patching but it works Ok. Would rather see class Foo(PropertyGroup): my_list : bpy.props.CollectionProperty(type=Bar)  and then Scene.foo = PointerProperty(type=Foo).  But would need to monkey patch to have a collection that is also type Foo.


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Draw object selector property without drawing entire pointer property button
I want to draw just the datablock selector button from the pointer property ui:

I tracked the operator down to bpy.ops.ui.eyedropper_ui, but when I draw it in a panel, the poll conditions are not met and the button is greyed out:

I assume that this is because the operator doesn't know which property to write the selected datablock to.
I had a look at the poll function in the C++ source code:

And while I don't know C++ it seems to say that there needs to be an active button in the UI which it takes it's data from.
Is it possible to fake this (maybe using something like UILayout.context_pointer_set) and draw the button on its own while satisfying the poll function?


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How to change render samples using python
I'm trying to render an image with python, and I want to set the render samples precisely, however, when I run this code:
bpy.context.scene.cycles.samples = 20

the number updates in the viewport but when an image is rendered, the number of samples it uses is unchanged.
I'm really not sure what happening here...

if you execute your line and ops.render.render() in the console, it works fine. try adding bpy.context.scene.update_tag() before the render command.

@FrederikSteinmetz hmm, I just tried that and it doesn't seem to be working, and now even if I edit it manually nothings happening

Sometimes Blender just doesn't update things when the code is executed "blindly", so you need to imitate like some parts of it were called by user. To do so you need to create and register Blender Invoke or Modal Operator and then call it with ('INVOKE_DEFAULT'). In the most cases it solves such problems. I've written and tested this Modal Operator, it works. Maybe there's even no need in the whole modal section and you could place context.scene.cycles.samples = self.samples and bpy.ops.render.render('INVOKE_DEFAULT') right inside invoke method and just return {'FINISHED'} from there, but I just wanted to ensure that the samples have been changed using the modal loop. More information about Blender Operators you may find in the API documentation And here is the code with lots of comments:
import bpy
from bpy.props import IntProperty

class SetSamples(bpy.types.Operator):
    '''Blender Modal Operator'''
    bl_idname = 'render.set_cycles_samples'
    bl_label = 'Set Cycles Samples'
    samples : IntProperty(
        name="samples",
        min=0,
        default=20
    )
    timer = None

    def execute(self, context):
        # in execute method we just create a timer and add a modal handler
        # which handles events in real-time. We set the timer to the class
        # variable to be able to remove it later on.
        self.timer = bpy.context.window_manager.event_timer_add(.1, window=context.window)
        bpy.context.window_manager.modal_handler_add(self)
        return {'RUNNING_MODAL'} # this starts the modal() method

    def modal(self, context, event):
        # modal handles events in real-time
        if event.type == 'ESC':
            # in case something goes wrong and we need to abort it manually
            bpy.context.window_manager.event_timer_remove(self.timer) # remove timer
            return {'CANCELLED'}
        elif event.type == 'TIMER':
            print('Tick!') # just a test to count how many times timer ticks
            # on every Timer tick the Operator checks:
            if context.scene.cycles.samples == self.samples:
                # if everything worked correctly and Cycles samples have changed:
                bpy.context.window_manager.event_timer_remove(self.timer) # remove timer
                bpy.ops.render.render('INVOKE_DEFAULT') # render
                print('FINISHED') # just a test message after
                return {'FINISHED'}
            else:
                # if samples haven't changed:
                context.scene.cycles.samples = self.samples # command to change samples
                context.scene.update_tag() # not sure what it does but it was recommended
                                           # in the comments to the question
                print(f'Cycles samples after changing: {context.scene.cycles.samples}') # test message
        return {'PASS_THROUGH'} # returns us to the start of the modal() method

    def invoke(self, context, event):
        # Operator starts to execute from here when called with ('INVOKE_DEFAULT'),
        # like if it was called by user, not by script
        return self.execute(context) # this starts the execute() method

def register():
    # as we use the Blender Operator class, it needs to be registered:
    bpy.utils.register_class(SetSamples)

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

if __name__ == "__main__":
    register()
    # after register you can use your Operator just like any other Operator in Blender
    # the last parameter is the samples you need
    bpy.ops.render.set_cycles_samples('INVOKE_DEFAULT', samples = 20)

I managed to get it working just by wrapping all my code in between
class SimpleOperator(bpy.types.Operator):
#
code
#
bpy.utils.register_class(SimpleOperator)


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Bending/deforming complex geometries
I am trying to bend a complex plate geometry, using the simple deform modifier however I am not getting the results I wanted.

Instead, after bending it looks like this:

Does anyone have any idea how to fix this? This is what the geometry looks like by the way:

Check if your deform modifier is limited to a vertex group, or upload the blend file if you can.

It's a question of object orientation, it bends the wrong way, try first to apply its rotation and see what you get

I never use a simple deform.  An armature modifier is better for any "simple" deformation I want.  Your topo here isn't great, and it will impact whatever you do.   You can't get a better deform than you have verts/topo.  Consider subdivision before modifiers here.  Pics of goal, and of course .blend file, would help people help you.

Hi :). Simple Deform modifier sometimes acts up, and you need to rotate your origin point to make it work correctly: https://blender.stackexchange.com/a/165766/78972


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How to connect objects and keep it smooth?
When I want to join 2 meshes in one object this happen. I am using mirror and smooth modifier. How I can join 2 separated meshes into one object and keep it smooth? What I am doing wrong?

if you join 2 objects into one it won't merge the 2 meshes, you need to boolean or to merge manually to have one unique mesh. If this is the case here, what you're showing looks like inverted normals

I merged it manually it is one mest but it is not smooth anymore

so smooth again and check the normals? Also make sure you don't have overlapping vertices or innder faces

@moonboots yes I did it but it doesn´t help. Vhat is the correct wayto join 2 meshes and avoid that shape ?

Could you please share your file?


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Invert "bake sounds to f-curves" f-curves?
Basically, I am trying to rotate the mouth bone of a model to simulate talking, and to do that I want to bake the sounds to f-curves, but the mouth moves up, not down. Any idea on how to invert the f-curves or the movement?

In pose mode go to pose menu, animation, bake action.
Then in curves editor select all and press S, Y, -1, Enter.

i cannot find curves editor, can you please tell me where I can find it? the only thing close to that would be the graph editor, but idk

Yes, graph editor, select the channel, select all baked keyframes and scale.

that did not work :(

nvm it worked i did it like a dumbass

sorry and thank you

well shit now the mouth is fucked :(

If useful please marke the answer as accepted.


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Texture from .png>dds
Is there anyone of you who knows if this question is maybe already answered.
All my textures in my .blend file are now .png is there any way i can change them from format with a little script to .dds so my export tool works correct for my game.
Thanks in advance

You would need to convert the files from png to dds fromat outside of blender; but you could write a script to find all of the png image files in your blend file and change the names to use the dds version.  This exchange on BlenderArtist has an example of how to do it for a single image.

Okay i already have all the textures set as .dds and they are all in a folder.
but the textures linked to the objects are still .png and to change every texture manually from png>dds takes a lot off time so i whas wondering if there is a script what can do it for me quickly

Ok so i tested it and i still got an little bugg
I added an video to make it more clear
https://streamable.com/htlr87

Assuming that you have all of your dds files in the same folder (directory) and each png file has a dds file that has the same name with png changed to dds, this script should do what you want once you've changed the line to point to your dds files.
import bpy

def find_nodes_by_type(material, node_type):
    """ Return a list of all of the nodes in the material
        that match the node type.
        Return an empty list if the material doesn't use
        nodes or doesn't have a tree.
    """
    node_list = []
    if material.use_nodes and material.node_tree:
            for n in material.node_tree.nodes:
                if n.type == node_type:
                    node_list.append(n)
    return node_list

path_to_dds_files = CHANGE_ME_TO_PATH_TO_DDS_FILES

for material in bpy.data.materials:
    texture_nodes = find_nodes_by_type(material, 'TEX_IMAGE')
    for texture in texture_nodes:
        if texture.image.name.endswith('.png'):
            new_name = texture.image.name.split(sep='.')[-2] + '.dds'
            new_image = bpy.data.images.load(filepath = path_to_dds_files + new_name)
            print(f"{material.name}: {texture.image.name}, {new_name}")
            texture.image = new_image
```

Thank you verry verry much


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How do I make it so that Blender would select everything no matter how much zoomed out I am

So If I zoom out and try to select mesh in Edit Mode, I am left with some vertices unselected.
Maybe because of the density of each individual point blender can't select the neighboring vertices.
So how do I select the entire thing even from a distance?
The transparent mode wouldn't help, because I only want to select the outer shell of the model, without touching the insides.

How are you trying to select and why doesn't just using the A key to "select all" work?

if you are using a solidify modifier, you should have written that in your question instead of downvoting an answer which would work, but this could nobody know what you are using....

I didn't downvote your answer.
it's not about solidify even.
I am using CTRL + Mouse over the mesh in edit mode, but because vertex points are too thick it doesn't catch all of the vertices.
I wanted to know a way around that.
Setting scale of vertex points in interface helps, but only a little bit.

Can't you use circle or lasso selection to select the outer vertices?

@blunder you can have similar problems with circle select in dense meshes.


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Can't see objects with basic camera
I did a big scene, but can't see it all in basic camera view. Even in rendered mod.

but i can see it in with created camera.

So i thinking there must be some setting for basic camera like for created camera in scene.

Please show your entire blender window for your first screenshot including the Properties menu (Press "N" key if it is not present). Or better yet upload your blend file.

its looks like u need to change in properties>view higher number for "end" value

Rumen is right. I had there 10m and that house has like 10,5m. I dont know how mark you comment for usefull so i writing this comment.

Also see https://blender.stackexchange.com/questions/8553/why-does-part-of-my-model-disappear-when-i-zoom-in-on-it-in-the-3d-viewport

Just scale the whole scene down so that it is going to fit in the camera distance.
Blender is acting very strange when there are so big scaled scenes

On the right side, you can also see the limits of the camera (the line)

Well done sir. You beat me too it.


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how to make new object from the duplicated part of other object in edit mode?
i need to make new object from part i duplicated from other object.

Select mesh and press P> Selection. In object mode, to join the mesh press Ctrl+J.

Select the part of the mesh, press P (separate) > Selection


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Why is this Mesh broken up?
I'm practicing with a mesh body from a game. I'm using XPS to import it into Blender, but the body mesh appears to be separated and not one uniform object. I can't find the mesh listed as an object in the layer tab either- am I uploading it incorrectly?

Sometimes Importers will separate things into multiple meshes, or even multiple separate objects. It looks like the mesh in the picture is still one object, but the mesh has been "cut" along various seams. First thing to try, in Edit mode, select the entire mesh, open the space-bar search, and and find the "Remove Doubles" tool. You may have to adjust the merge distance option, depending on the size of your mesh.

not sure that's the right tool to use to get these 2 pieces back together. Keeping the merge distance as low as possible, it doesn't appear to have an effect- pieces are still separate. When I raise it to 0.1, the leg start to collapse in on itself. If I convert it to an object and join the pieces, I can edit them both simultaneously, but they're still separated.

*I also tried merging the overlapping vertices but the areas still register separate.

Is the mesh in the picture one object, or multiple?

I imported this from an xps file so I'm not sure, the obj wasn't showing up. So I exported it as an object and re-imported it to find 2 objects, the groupings you see.

Ok. In that case, from Object Mode, select both objects and press ctrl+J to join them into one object. Then try my suggestion above.

I did but there's still seams :l

Can you post the .blend file?

oh! I found out what it was! The blue lines were an indicator that it's "marked as sharp"- so I unmarked it! Whew, that was a small fix and a rough learning experience lol thank you for your help with merging the mesh Andy <3


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What's the name of this Tool/Feature?
In advance: newbie here, thanks for your help! I used to play around with NURBS in Maya and loved this feature where I could mold the object like clay- pushing and pulling with a red/yellow mapping of the strength. Though, I don't remember what the tool is called or if its even the same for mesh/Blender.
I have a model I want to move uniformly instead of just the faces/vertices I select- which gives long, hard lines instead of a gradient. Example: I need to move the arm up in a T-pose, but if I select it to rotate and generally manipulate it, there's an unnatural edge to where my selection starts/ends. How do I get the option to click a point, see the radius of strength, and then push/pull so it moves all in the radius uniformly?

I'm pretty sure that's proportional editing.  press o to enable it.

See https://blender.stackexchange.com/questions/21131/is-their-a-way-to-move-multiple-vertices-gradually-at-a-time

Blender do support NURBS BTW. But it is not that simple compare to polygon vertices.


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Trying to render an emission layer with environment reflections on transparent background in cycles
Long time lurker, first time poster.
I am making a rendering for a video wall during a live performance coming up, and what I am trying to achieve is two separate renders;

the background/environment, unaffected by the pink "Laser Bridge" and its emission reflections,
and the laser bridge itself with its pink reflections on transparency that can then be overlayed over #1.

I have done a lot of learning of how to composite render layers and such, but given I am no expert, I am looking for advice.
I illustrate what I am trying to achieve in the diagram below. The three colored layers represent layer #2 (only separated by color to indicate what I will be doing in my live performance, shifting the hue of the laser and its reflections on the environment, thus why I am trying to render it out separately)
The gray layer represents layer #1, which also contains the white emissive environment lights you see in the two renderings below.

This is the environment layer with the white emission textures on the lights as you can see. I am not done texturing the scene but I wanted to get this problem out of the way before I continued.

Below is what the final thing should look like when I overlay both the environment layer and the laser and its reflections in my live performance

I have not found any solutions, and I am probably making it sound more convoluted than it is, but any help would be appreciated.

Bump? Is that a thing?


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Problem with parented control bones? affect other values that should not be effected
I have two control bones that control the shape key of each eye respectively. And then I have constrain (child of) these bones to one main bone (in center), so that I don't have to grab each bone to control the blink. now the problem is that, I have parented the main blink control bone to the rest of the rig. Now whenever I move the rest of the rig down the character close it's eyes. I don't know what to do now?

could you share your file so we could test it?

I can't share the full file but I will try to share the parts that have problem


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Material not showing full geometry
Okay, I'm not sure if the title is quite accurate but I'm having an issue with materials in a blender project I'm working on. I'm working on a model of a truck (as you can guess from the colour it's based on Optimus Prime, it's a private project)
Now the first picture I've got is the model in solid (I use 2 monitors, I don't know how to print screen only one so the left side is BTS of this post)

You can see there is geometry on the surface, such as the bit the spoiler's mounted on, the wheel arches, the frame behind the window etc.
Now this is the the same model in material preview
You can see the probleme, or rather you cannot, all the geometry I previously discussed is impossible to see, for that matter you cannot even see the edges of the shape, if the textures were coloured black it'd look like a silhouette for additional reference here is the Shader Nodes

Please, anyone with suggestions, tell me how to make the materials show the edges.

The normal map should probably be set to non-color.

Just tried that, didn't work.

Not ideal but removing the Bump worked.

for screengrabs we don't need to see the second monitor... in blender you can use Window > Save Screenshot. (or crop the images to show only the relevant information)

Thanks, not the specific issue I was struggling with but that's still helpful.


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Controlling Shader Node Sliders outside of Shader Mode
It's not a major issue but I felt that if someone knew how to do it it could come in handy. I have a tendency to use a fair few textures using sliders, particularly mix shaders or emission nodes which I want to use to switch between different settings. Now as far as I know the only way to control these sliders is to open the shader editor and interact directly with the nodes, and it can get mildly irritating.
Now sliders connected to the direct output node appear on the materials tab, does anyone know a technique to make sliders on other nodes appear on the materials tab or as well? Or another way to adjust the sliders outside of shader mode.

You can expand the nodes in the properties window with the small arrows to the left and control any sub nodes, albeit with some digging

Thanks, that'll help out a lot in the future.


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Is there a way to color different strands of curve hair without using multiple hair objects?
I'm fairly new to doing hair using the new-(ish) curve hair system, And basically want to know if there are ways to, as I wrote, make a single hair system with different colors, to offer an elaboration I have some examples: In this picture of Reed Richards we see the back of his hair is white while the rest of his hair is brown, probably the easiest to just do multiple hair systems;

The next image is of Jason Todd from Gotham Knights, in which he has a white streak of hair running right through the rest of his hair, a far more difficult effect to replicate with multiple objects, since I'd have to match the grooming of one part with the other:

Does anyone know a way to make something like this work?

Thanks, that will work perfectly. In hindsight I cannot believe that It's that simple and I hadn't stumbled on a tutorial for it.

Great that it worked for you. I'm going to vote for this question to be marked as a duplicate.


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Geometry nodes: Morph between two meshes with UV
Okay, I have no idea if this is possible but I figured it's worth trying I am working on a concept using the geometry nodes morphing effect seen in my example below.
Now, what I am trying to achieve is to have the morphing object to use to two source object's UV map. So when the object is in sphere form it has the UV Map of the Sphere, and when I morph it into a Cube it switches to the UV Map of the cube.

To offer a better example of what I am talking about, here is a basic example of the texture I would use on the morphing object. I don't know how to make the UVs work here, beyond obviously storing them as attributes (I don't know if it could store it as a single UV that morphs with the mesh, or if it should be stored as two separate UVs, one for the Sphere one for the Cube) with a second/third attribute or a driver controlling the Mix factor.

And to be clear the end idea isn't a cube and a Sphere, the idea would be clothing on a character that can morph into different forms (think how Dr Strange's clothes morph from the suit he's in at the wedding to his Sorceror Robes in Multiverse of Madness) with the different forms featuring texture painted details, necessitating the UVs.

If you morph your mesh correctly, there's no additional step needed to morph UV. Yes, if your two meshes are unwrapped differently, you would need somehow to switch between the two, but any interpolation will cause some faces to travel a long way across the UV space, because you have no guarantee for a face to be in similar place in UV space for both forms. I'd recommend to only unwrap UV once, and after morphing to the other shape, bake the used texture using morphing target and old UV to the morphed mesh and new UV.


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Mist with Photo in compositing
I have a problem with Mist.
I am compositing a photo with blender, using the cool mist tool.
The problem is I don't have any clue how to exclude the foliage over my cosplayer model.

This is my cycles node so far. I suppose I need to add another mix node, but I didn't succeed without excluding the entire photo.

You could use the Alpha Over node for combining it and using the mask to exclude anything in the area of the character.

@rjg that's what I was thinking, but I don't know where to put the alpha over or the combination to achieve this

I'd say alpha over last (before the color grading), if the character isn't supposed to be affected by the mist.

@rjg the thing is the mist should affect the character, but you can see too the foliage is transparent in the body of the model


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Trying to set transparency on the viewer Node
First time posting in blender but it's important. Thank you for your support.
I have a model which have a Mix Shader with Glass and transparency shaders mixed, both with a texture as Color.
When I use the nodes for compositing, the glass of the model doesn't transparent with the background. If I set to Multiply, all the model multiplies and I can see through the glass, but cannot with Mix.

Someone can help me with these? Any advice for handle those situations? Thank you very much.


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Can a curve be a parent of a bone?
I would like to control multiple bones with a bezier curve but I don't want them to follow the path of the curve.
I want the heads of the bones to follow the curve without rotation. Is it possible ? Can their tails be fixed to a position and the heads still follow the curve ? And a last question can the heads ans the tails be attached to 2 different curves ?
I'm animating a dragon and i want the wings to follow the exact shape I want without moving every bones of the wings. It would be so easier and faster if blender could do it.

What you're asking for, and showing with your pic, sounds a lot like the behavior of bones with a clamp-to constraint.

These four bones, parented unconnected in a row, each have the same, copied clamp-to constraint that keeps them clamped to the curve, without affecting their rotation.
If I duplicate this structure, then add damped track constraints to the bones, I get this:

The heads of the bones are clamped to the bottom curve, while the tails point to the top curve.  Note that I have to specify where on the top curve they point, with the top four bones.  These four bones couldn't be parented directly to the bottom four bones, because that would involve a dependency loop, but both could be parented to the same (unpictured) bone, so that bone slid them along their respective curves from the same controls.
Note that the bottom bones don't reach the top curve, they only point at it.  In order to reach the top curve, you could add stretch-to constraints for the bottom four bones.
Finally, be aware that tails don't mean very much, not as much as they seem to.  The location of a tail has absolutely no effect on deformation-- any unconstrained bone will rotate, scale, and translate in the exact same ways, regardless of where its tail is located.  Tails are useful only for controlling local bone axes and for use with some constraints.


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GeoNodes - Convex Hull Triangulation Issue
I’m having some issues with the convex hull node on my wrap generator.
The wrap generator basically uses a difference Boolean between a plane and the object (a hand in this case) you want to wrap around, deletes everything that is NOT intersecting edges, convert to a convex hull, then converting to a curve to get the boarder edge to deform geo around.

The problem is I am finding that the convex hull node is very unpredictable with triangulation. If you intersect a flat plane with an object, it produces a nice clean Ngon which makes extracting the border edges very simple. However if you introduce any rotations to the plane, the convex hull is very heavily triangulated and not useable.

So far my workaround was to extrude the convex hull to give it thickness and then Boolean the original plane with the extruded convex hull to get the intersecting edges but it does not produce predictable results a lot of the time as the extrusion is all over the place due to the messy convex hull topology.
Does anyone have a workaround to getting past this, is there a way to perhaps force the convex hull to always produce an Ngon to avoid the triangulation?
Thanks!

"normally" geometry node questions are answered very fast (and i tend to prefer the ones with blend files, so i don't have to waste my time recreating everything manually).

It's hard to help without an example .blend file in this case, I would try taking the convex hull, merge by distance (so it's flat and single-sided), then remove edges that have 2 neighbors (internal edges). Then convert to curve.

Thank you for the response!
I ended up finding a solution on the blenderartists forum from the user Zebr4he4d.
Thread here:
https://blenderartists.org/t/geonodes-convex-hull-triangulation-issue/1509445/2


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I want to make "god rays" in my nature scene
I am now busy with my first nature scene ever in cycles but I can't seem to get the hang of god rays for my scene, in a very simple scene with just a window I got it to work but it doesn't work out for this scene, I watched every tutorial I could find but still then it doesn't work, so you guys are sort of my last resort :), see the images for my settings and scene

And my goal is to get god rays through the trees.
Thanks in advance!

Unrelated to the question, but related to your scene: cycles water.


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no transparency in cycles render
I'm sure someone already asked this, and yes, i googled it, but in cycles render, i do not know how to fix the transparency problem here. however, transparency works fine in blender render, so it is not my laptop not being able to support it.

i need to get rid of the black
i have a separate alpha png, but dont know how to apply it

if your PNG has a transparent background, plug the Image Texture with your image in the bottom entry of a Diffuse, plug this Diffuse in a Mix Shader, and plug the Mix Shader in the Material Output. Now plug a Transparent BSDF (100% white) in the top entry of the Mix Shader, and plug the Alpha output of the Image Texture in the Factor of the Mix Shader. It should work

This might not be an answer for the general transparency problem, but there is an Addon called "MCprep" that automaticaly sets up your exportet Minecraft-World for Cycles/Blender internal...

i already used mcprep... only works for blender render for me...

i DO have an rgba, but no difference is shown between the rgb and rgba

If your PNG has a transparent background, plug the Image Texture with your image in the bottom entry of a Diffuse, plug this Diffuse in a Mix Shader, and plug the Mix Shader in the Material Output. Now plug a Transparent BSDF (100% white) in the top entry of the Mix Shader, and plug the Alpha output of the Image Texture in the Factor of the Mix Shader. It should work

does not help me at all... still showing black in the texture.

are you sure your PNG have a transparent background?

i didnt say that. i said i also have an alpha png to render transparent stuff

also, i can obfuscate to get rid of the black, but its a hassle

maybe share a file with just the object so that we can check (and pack the PNG)

ill send u a zip of the entire project... be prepared for a minecraft one...

Need to turn on "Transparent" on the render settings panel.

The problem is with surface transparency - that setting only affects render result background transparency.

please remove this answer... i would delete it if i could