text:
Draw a sine wave from a revolving unit circle in blender
In Blender 3.2.1, I need a unit mesh circle at origin and path on the x-axis with a length of $2\pi$. Object constraint on circle to follow path. Keyframe on unit circle at 0 & 250 with $360^{\circ}$ z-rotation. How do I get a single vertex on the unit circle to trace the sine or cosine wave?

could you pls tell us what your end goal is?

i want to trace the sine/cosine wave from the rotating unit circle.  i just dont know how to get the vertex to trace the path.  it is a step in a larger gear driven idea.

i still don't get it. you only get a sin or cos wave, if you would move the circle while following path. If the circle is fixed, you only get a right left or up down movement. So what do you want?

do you want that? [1]: https://i.sstatic.net/o8cI9.gif

https://blender.stackexchange.com/questions/48866/draw-line-from-armature-animation/ https://blender.stackexchange.com/questions/104732/is-it-possible-to-achieve-a-spirograph-efect  https://blender.stackexchange.com/questions/261399/how-can-i-trace-an-object-that-move-along-equation

If the circle is moving along the line while rotating, the path scribed by a point on its circumference is a cycloid, not a sine wave ?

yes, the way i was describing it wouldn't give a sine wave.

Just copy the script and execute then press spacebar in the Timeline to play the animation or you can scrub through the timeline from frame 0 to 250.

import bpy
import math

REVOLUTION = 360
TOTAL_FRAMES = 250
SINEWAVE_RESOLUTION = 64
RADIUS = 1

bpy.context.scene.frame_start = 1
bpy.context.scene.frame_end = TOTAL_FRAMES
bpy.context.scene.frame_current = 1

def get_object(name):
    objects = bpy.context.scene.objects
    if name in objects:
        return objects[name]
    m = bpy.data.meshes.new(name + "-mesh")
    o = bpy.data.objects.new(name, m)
    #o.modifiers.new(name, 'SKIN')
    bpy.context.collection.objects.link(o)
    return o

def get_empty(name):
    objects = bpy.context.scene.objects
    if name in objects:
        return objects[name]
    bpy.ops.object.empty_add(type='SPHERE', align='WORLD', location=(0, 0, 0))
    empty = bpy.context.object
    empty.name = name
    empty.scale = 0.1, 0.1, 0.1
    return empty

# ==================================================================================================
# Descritpion: plot the sinwave with some points
# ==================================================================================================

def get_range(start, end, step = 2):
    return [x * 0.1 for x in range(start * 10, end * 10, step)]

def get_sinewave_x(angle):
    return RADIUS * math.cos(REVOLUTION - math.radians(angle))

def get_sinewave_y(angle):
    return RADIUS * math.sin(math.radians(angle))

def get_sinewave_length():
    return RADIUS * 4

def draw_sinwave(angle, id):
    verts = []
    xunits = get_sinewave_length()
    for u in range(0, SINEWAVE_RESOLUTION + 1):
        a = u / SINEWAVE_RESOLUTION * REVOLUTION
        px = xunits / SINEWAVE_RESOLUTION * u
        py = get_sinewave_y(a)
        if (a <= angle):
            verts.append([px, py, 0.0])

    #verts.append([xunits, 0, 0.0])
    edges = []
    for i in range(len(verts)-1):
        edges.append((i, i+1))

    o = get_object("sinewave-" + id)
    m = o.data
    m.clear_geometry()
    m.from_pydata(verts, edges, ())

# ==================================================================================================
# Create Circle
# ==================================================================================================

def create_circle(n):
    o = get_object("circle")
    exists = len(o.data.vertices) > 0
    if exists:
        return o

    verts = []
    for i in range(n):
        verts.append((0.0, 0.0, 0.0))
    edges = []
    for i in range(len(verts)-1):
        edges.append((i, i+1))
    edges.append((i+1, 0))

    m = o.data
    m.clear_geometry()
    m.from_pydata(verts, edges, ())
    return o

def draw_circle(r, segments = 32):
    o = create_circle(segments)
    o.location = 0.0, 0.0, 0.0

    for i in range(segments):
        a = 2 * math.pi / segments * i
        o.data.vertices[i].co = math.cos(a) * r, math.sin(a) * r, 0.0

# ==================================================================================================
# draw lines connecting circle and x-axis
# ==================================================================================================

def draw_line(x, y, px, py, id):
    o = get_object("line-" + id)
    m = o.data
    verts = m.vertices
    exists = len(verts) > 0

    if exists:
        verts[0].co = x, y, 0.0
        verts[1].co = px, py, 0.0
        return

    verts = []
    verts.append((x, y, 0.0))
    verts.append((px, py, 0.0))

    m.clear_geometry()
    m.from_pydata(verts, [(0,1)], ())

# ==================================================================================================
# draw geometry
# ==================================================================================================

def draw_empties(x, y, px, py):
    get_empty("empty-1").location = x, y, 0.0
    get_empty("empty-2").location = px, py, 0.0

def draw_circle_angle(angle):
    rad = math.radians(angle)
    draw_circle(RADIUS)
    l1x = RADIUS * math.cos(math.pi * 2 - rad)
    l1y = RADIUS * math.sin(rad)
    l2x = angle / REVOLUTION * get_sinewave_length()
    l2y = get_sinewave_y(angle)
    draw_line(0, 0, l1x, l1y, "1")
    draw_line(l2x, 0, l2x, l2y, "2")
    draw_empties(l2x, l2y, l1x, l1y)

# ==================================================================================================
# animation functions
# ==================================================================================================

def animate():
    f = bpy.context.scene.frame_current
    angle = REVOLUTION / TOTAL_FRAMES * f
    draw_sinwave(angle, '1')
    draw_circle_angle(angle)

# ==================================================================================================
# execute code
# ==================================================================================================

def on_enter_frame(a,b):
    animate()

bpy.app.handlers.frame_change_post.clear()
bpy.app.handlers.frame_change_post.append(on_enter_frame)

draw_sinwave(REVOLUTION, '2')
on_enter_frame(None, None)

for o in bpy.context.scene.objects:
    o.select_set(True)
bpy.context.view_layer.objects.active = get_object("sinewave-1")

bpy.context.scene.objects['sinewave-2'].select_set(False)


text:
Is it possible to display vertex normals in object mode?
I want to preview how vertex normals will look like after WeightedNormal modifier without actually applying it. Is there any way to do that?
I am aware about Y.A.V.N.E. addon but it hasn't been updated to work with 3.0. (yavne and blender face strengths are not the same which adds confusion).
"On Cage" button isn't an option because I might have some generative modifiers before the WeightedNormal.

It takes a while to find it but it does work in Blender 3.0! Check in the Tool sidebar, under Workspace, and you can turn YAVNE back on. It will be in the Extended Tools panel, not in Tool anymore.

Can't get it to work. Can you please upload some screenshots with these settings and with YAVNE normals showing in the Object Mode?

source: Stack Exchange

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

sort: votes


text:
How to start animating folding fan like this?
I'm having a bit of a problem on how to animate a foldable fan for an animation that I'm making
you twist the circular wire then it folds unto itself
How do I make this kind animation?

This is what I came up with using a curve circle and adding shapekeys.

I added the shapekeys in every frame of the timeline
since its a curve circle I also shaped key the mesh inside the curve circle trying my best to align them to each other but both are not calculating it the same way so I'm getting this

bad alignments on my animation.
Also I think my animation is not really representative of the look that I want.

Thanks. Another note that might help you get answers faster. You should show efforts towards reaching your goal, describing what you have tried and why it failed, so we don't risk recommending something you already know. The scope should also focus on a particular step you encountered an issue with. Describing the whole procedure from start to finish would be too lengthy to explain, and is beyond the goal of this site. Could you [edit] your post to focus on where you are stuck?

Thanks, I'll do this.
Sorry I if don't know how to use the forum.
is it possible to post gif or video here, and is it ok to post lengthy post?
Thank you so much for the help.

https://blender.meta.stackexchange.com/questions/963/what-is-the-process-for-creating-gifs-for-questions-and-answers

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


text:
If Cycles is Physically Based, Why Doesn't it Calculate Fresnel Automatically?
So, supposedly Cycles calculates light bouncing around fairly accurately to life.  If this is the case, and if Fresnel truly is an optical property due to the viewing angle, why doesn't it just happen? Why does there have to be a node for it?

Cycles could have a shader with in-built fresnel, in fact one is being worked on: https://developer.blender.org/D2313
The reason fresnel is a separate node used to mix diffuse/glossy shaders was an intentional design decision to allow more flexibility when putting shaders together. It allows you to mix shaders in any way you need. One problem with this is that a lot of the time you need to combine shaders in the same way. The alternative is an "ubershader" that combines everything in one black box, such as the Principled BSDF shader in that patch link. By adding the Principled BSDF as a shader node you'd have a single node when you needed a general-purpose physically based shader, or you can choose to roll your own shader combinations if you need more control.
The drill down into your core question of "why doesn't it just happen?": you don't just code "do things physically" and BAM, the renderer is realistic. You need to code each step of the rendering process so that it behaves the way real light would. In the case of Cycles shaders, this step is (currently) left to the user.

Cycles' focus is production rendering, where ultimately artistic control is more important than accuracy. Leaving shaders to the user makes sense in that case, as not all physical effects are desirable in a production setup.

Thankfully, the Principled BSDF shader should simplify this pain on the user side.

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


text:
How to make fire less "chunky"
I was working a little bit with fire simulation today.
I used a particle system on some text that I converted into a mesh. I'm very satisfied with the smoke, but the fire looks kind of "chunky" with a chunk of fire for each particle.  I'm using a particle system with 200,000 particles over 85 frames.
I hate to infringe on anybody else's copyright (this picture is from this link) but this guy got a very nice "non chunky" fire effect.

What parameters can I change so that I can achieve this effect?  (I'm using Cycles.)

I don't think that person is using a particle system to make the fire. There is a smoke simulation feature in Blender where the fire is actually converted to smoke and it looks much more realistic, and you don't need to use a particle system to do it. https://www.youtube.com/watch?v=i-IbKIdL1WQ

@Sanix25 Okay, cool! Is this possible in Cycles? From what I understand, using a particle system generally gives you more control over the fire. Is this not the case?

Using a particle system won't interact with the smoke. It won't experience vorticity. It's a living nightmare to try to make it photorealistic. If you use the fire setting that comes with the smoke simulation, it will easily allow you to make photorealistic fire, at the expense of certain controls like materials. However, it allows you to make extremely realistic fire and if you're trying to achieve photorealism, I would definitely recommend using it: https://www.youtube.com/watch?v=aeNPNOzIgTU

Also, It seems like you're trying to make the word "Fire" out of fire. I would recommend using a text object, extruding it, and assigning it an emissive material. After that you can set it as the emitter for smoke + fire (if the text disappears during the render just duplicate it before setting it as the smoke emitter, then just set 1 of the 2 identical objects as the emitter).

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


text:
How to install the Avid codec for use in Blender
This might sound like a fairly uneducated question, but I'm asking the question because I'm uneducated.  My uncle works in the visual effects industry, and he told me that Avid makes a video codec that has great quality and can even render with an alpha channel.  Does this codec exist (I haven't been able to find it)? If so, how can I install it on a Linux Mint machine for use in Blender?  Thanks!

The later era Avid format is DNxHD, with the more recent DNxHR.
FFMPEG is capable of decoding DNxHD. If using proper libraries, Blender would import DNxHD as an 8 bit per channel image, likely sub-optimal. Blender relies on swscale from FFMPEG to convert the (typically) YCbCr planes to RGB, at 8 bits per channel.
DNxHD is not a reliable format for visual effects, nor is any codec for that matter.

Okay, sounds good.  Thanks for the answer!  Do you know of any other video format that can carry an alpha channel?  I understand that this can be accomplished with .png image sequences, but I'm just curious.

No. QuickTime on OSX permitted a variant, but it is wiser to use a still image format for inter-pipeline work, in particular EXR. Remember that PNG is a janky format due to alpha storage and the nature of this quantization.


text:
Random Image Sequence Start Frame
I'm making a movie that has a scene that kind of imitates the speech scene in Star Wars 7. https://youtu.be/MPhHl2DpD4E?t=1m1s
Note how the storm troopers all perform similar motions but they are all slightly different? I realize that these storm troopers were probably 3D models, but in my scene, they will be a person in front of a green screen (thus alphamasked image sequences in a large array of planes). As I can't see a way for the random output from the object info node to plug into the image sequence offset, how can I randomly drive this parameter per each plane?

Can't help but think that it would be easier to create multiple unique versions of the plane with texture material, then use a script to add a driver to each that sources a random value? Perhaps you could multiply the random value by obj loc?

This is a round about way to do it, and will not perfectly randomize the textures, but I used this technique to randomize a drawn animation of grass for a project last year.

Hey, I guess that works :) I'll try it out and get back.

Yeah, it worked! Thanks for the answer. This seems like something that Python would clean up a lot, ya know? But it works!


text:
Weird reflections
I made a lightsaber, and it's looking pretty good, but I have a few problems.  When I render it out, it looks like this:
However, in the viewport rendered shading, it looks like this:

How come the exact same scene can have different reflections?  I would like the rendered image to look like it does in the viewport.  How can I do this?

The viewport render uses the viewport settings for modifiers, and visibility setting for the viewport. Perhaps your Display and Render settings for a modifier, or the visibility of something in the environment, are different?

It looks to me like you have a subsurf or maybe a bevel modifier which is being not being applied in one or the other. See http://blender.stackexchange.com/q/985/599 for a list of possible causes.


text:
Text in Blender Game Engine
I have some text parented to the camera to show how many lives the player has.  In the viewport, it looks like this:
But in the game, it looks like this:

How can I fix this?  Thank you.

I think ,This is because the text object is treated as a text in the BGE render , there is an option in User_preferences->System->text_anti-aliasing  uncheck it and change the size of the text

it seem that nothing from its properties is considered as if it is passed as a string to the render engine

Duplicate of this You will find links to tutorials that address this in the comments. This answer also explains the issue.


text:
How do I delete the connection between these 2 vectors?
I am new to blender and I am trying to make a neon sign
I have this connection here that I am trying to delete

when I delete the vectors on the curve I get this

I am trying to have this as empty space but nothing I am doing is working to delete this connection
Edit:
I figured it out, I selected the 3 points and split it
then I deleted the split points
which got me what I wanted

Select the controls that define the segments you want to delete, then x-> delete segments:

This works for curves with their own geometry.  Note that some uses of curves, like a curve modifier, are only built around the existence of a single spline inside any given curve object; you may not get the results you expect.

When I tried deleting the segment it would keep the connection. I figured it out by splitting the segment then deleting that sectiong. Thanks for your help!


text:
Pokemon mesh breaks apart during animation

I'm reapplying Pokémon animations to their respective models. However, when I reapply them, the mesh breaks apart. I tried merging the mesh Mesh>Merge>By Distance, but no luck.
blend file:
https://drive.google.com/file/d/1FHOADOMJwoq_T3Yb_w69cESij1OBKjIy/view?usp=sharing

pls provide blend file

Sorry I'm bad at this. Here you go!
https://drive.google.com/file/d/1FHOADOMJwoq_T3Yb_w69cESij1OBKjIy/view?usp=sharing


text:
how do I delete geometry with proximity?
I am trying to use this empty cube to delete these cubes and whenever I try to use location to delete geometry it doesn't work

It is unclear what you are asking without images of your settings. Please use the [edit] link at the
bottom of your question (https://i.sstatic.net/lXFuK.png) and add
more information on how you set up your project.
Add images that
might help us understand your scene and settings. See How to upload
an image to a post?.

alright, I didn't know it was vague

You can't "just" use location to delete the geometry. You can however plug a Vector Math node set to Distance and then a math node set to Lower than and set your desired value there. Plug it between the Location output and the Selection input

Thanks, but I gotta play with it a bit to make it work how I want it

It's not just as easy as @Gorgious described and it also depends on what you want. For example, the Vector Math node also needs a Position node plugged in and your Delete Geometry node has to be set to Instances if you want to delete complete cubes (assuming from your question) without loose edges or vertices remaining - but then you can't use Realize Instances beforehand or it won't work. The other thing is, Distance deletes spherical around the cube's origin. If you want Delete Geometry to take the cube's shape into account, you need Mesh Boolean (cutting the cubes as well).

(I was running out of space) If you don't want Mesh Boolean to cut the small cubes in "fragments" but delete complete cubes instead, then you would have to use Mesh Boolean earlier on the geometry which is used to distribute the points.

i am not sure whether you understood the "selection": it is just a boolean, so it just takes two values: either 0 or 1. So plugging a location into a selection makes no sense.

If you want simply to delete instances, or geometry such as vertices, by distance from an Empty, there is no need for the (quite pricey) Geometry Proximity node. You can just use the Distance between the Empty's location and Position

.. if you mean spherical distance.

If you want cubic distance, you have to test against X,Y, and Z independently, one way or another:

like so:

Geometry proximity works like this:

Note: Geometry proximity is called "geometry proximity" because it needs geometry, which means mesh in this case. It does not work with empties.
result:

Note: Geometry Proximity also means, not only it needs geometry but it also only works where there is geometry. This means (of course depending on the threshold distance) that there are (or could be) instances reappearing inside the sphere.

You should mention that Geometry Proximity also means, not only it needs geometry but it also only works where there is geometry. In your above example I assume the sphere is hollow - no geometry inside. This means (of course depending on the threshold distance) that there are (or could be) instances reappearing inside the sphere. Which is no problem if the sphere covers them, but if you use invisible objects to remove something "magically", then they will show up (which is why I mentioned Mesh Boolean in my above comments to get rid of them). But still: +1

thanks, added that to the answer


text:
Why are parts or even entire islands for the UV map not colored when baking texture?
[Added files for reproducing the issue at the end, thanks for the feedback, Nathan]
I imported a received trailer model from .fbx and used smart UV project to get the UV layout. I then added a texture image node for each material, played with the UV resolution and bake settings to arrive at the currently best result shown in the image below.

The problem is this, several UV islands remain partially black or even completely black, illustrated in the close-up below.

This results in black spots for the textured model, like here.

When importing the model from .fbx, you can see that the model has various materials and some are double. Also, not every material is assigned to the right model part. Therefore, I've reassigned some colors right after importing the .fbx. So I tried to reproduce the issue by baking immediately after importing the model without making changes for the assigned materials and got the same result.
I am new to Blender and I would like to know why this problem occurs and what I can do to avoid it. For reproducing the results, here are links to dropbox for the blender file and the .fbx file.

What were the materials, and what was the bake type?  To answer this, people would need more info, and the best way to provide that info-- since you don't yet know what the relevant factors are-- is to link a .blend file.

I can't find the geometry in your last pic, or I'd inspect that carefully.  Otherwise, look at your second pic: the faces are smaller than the image pixels!  You simply don't have the image resolution to even see these faces on your image.  Also, check out and fix your normals.


text:
Instance alignment on corners while maintaining right angles
I'm trying to align corner pieces so they always face inwards and also maintain right angles, like so:

By aligning instances to vertex normals I'm getting something like this (red face is always pointing inwards, so it's doing something right):

Current nodetree:

Earlier I tried to rotate or mirror instances by selecting them manually via vertex IDs, but that's tedious and not at all dynamic.
So the question is: what kind of vector math magic can I use to get the result in the first picture? Can it be done with vertex normals, or perhaps by somehow referencing neighboring points to get the orientation?
.blend file can be downloaded here.
PS: another question that was suggested while composing this one (How to properly orient instances along corner edges) didn't help very much.
Edit: typos
Edit 2: Temporary solution
I was able to scale (mirror) instances depending on their position in relation to bounding box center (if it's below, mirror along Z axis etc.):

That did the trick, but sadly it only works with simple boxes.
Or you'll get something like this where mid-level corner pieces are incorrectly pointing upwards as they are below the bounging box center (this problem also applies to X and Y axis):

Here's a way for all corners (except ambiguous).

Since the base mesh has a simple structure (Edges are aligned to X, Y or Z axis, normals and edge angles don't vary very much, except for the sign), the normals of the vertex and edge angles of connected edges can be used to determine if a vertex will get an instance or if  it needs additional rotation.
If edges with angles equal to $0$ are ignored, determining if a corner is concave or 'semi-concave' is much easier (especially if there is inset faces). They can be ignored by transferring captured edge angles (captured to edges) from a mesh with edges of angle $0$ deleted:

Here's some values and what they mean here:

If the vertex has a number of edges equal to 3 (ignoring edges with angle $0$), it is a three-point corner.
$$$$

'Semi-Convex' corners (with one concave edge) have an average edge angle of $\large -\frac{\pi}{6}$.
$$$$

Fully concave corners will have an average edge angle equal to $\large -\frac{\pi}{2}$.
$$$$

Ambiguous corners (concavity of surrounding edges equals convexity) have an average edge angle of $0$, this is also true for non corner points (surrounding faces face same direction). Instances weren't put here.
$$$$

'Semi-Concave' corners (with one concave edge) have an average edge angle of $\large\frac{\pi}{6}$.
$$$$

Fully convex corners have an average edge angle equal to $\large\frac{\pi}{2}$.

We can use these to do specific things depending on the properties of the corner.
Geometry Nodes:

Here only convex corners are selected:

You could put a different instance on ambiguous corners by checking the edge angle and using the result as instance index:

+1. Missed this one earlier. Really nicely done.

Sorry for the long wait! I was honestly hoping to dissect your solution to get some understanding of how exactly it works and only then reply, but then life happened. I did not have a chance to dive into it, so I'll just mark it as a solution. All I can say is that it just works, and thank you dearly for your time!

In the end, I did it with face normals by using three compare nodes and three switches. Compare nodes look if normal points in certain direction (positive X, negative Y, negative Z) and switches pass the corresponding scale value down the line where it gets added together and plugged into instancer's scale input:

Result:

All thanks to this guy Kammerbild on YT: "Blender: procedural buildings with geometry nodes fields | pt. 2"

How are you selecting convex v concave corners?

@RobinBetts, if I understood correctly, you're referring to the fact that some vertices don't have corner pieces on them. I've somewhat cheated by using Vertex Neighbors and Math Less Than 4 nodes and plugged them into instancer's selection input. So any vertex that has 3 or less neighbors gets selected (you can see that in a nodetree screenshot in original post).

Thx, sorry, missed it. :)


text:
My pocket watch is not visible through it's glass except
I am using eevee and blender v2.93.3. My pocket watch glass uses a glass bsdf that works but nothing other than the hands appear, not even the body itself.

After looking at the normals, it appears that my watch body has no normals. The watch body and face image are the only objects not using a principled bsdf.
I have tried to recalculate normals inside and outside and flip normals, add a solidify modifier to my watch body but nothing has worked so far.

Here are the nodes for my watch body and face if it helps.

-----Update:-----
I forgot to add in a photo of the node I used for my glass so here it is. It's really just a glass bsdf.

I tried changing it based on Christopher's suggestion but the problem seems to persist.

That seems to be a strange node setup - firstly, image textures usually use UV texture coordinates. Also (although I cannot see it in your graph), you mentioned you are using a glass bsdf and eevee - glass bsdf is meant for cycles, use a principled bsdf with transmission set to 1 and roughness lowered instead. Make sure to the set the Material's Blend Mode to something other than opaque (alpha-blend should work).

I just started learning blender not too long ago and followed some tutorials to make this so sorry if it's weird. I'll try your method.
How do you determine which node works for which rendering engine?

Blender has come a long way in terms of making all nodes "work" for both engines, but due to the difference in renderers, some things don't translate well. Transparency is one of them and the glass bsdf took the biggest hit (although they have begun to re-optimize it for eevee in the most recent releases). It still doesn't look quite right, so the convention for eevee for glass is still transmission 1, roughness ~0.

Ah I see, guess I'll need to read up on what works and doesn't then, thanks for the info. Also, I tried your method but the problem seems to persist.

After some checking, the problem is actually screen space reflection being turned on for both the body and watch face which makes it transparent through the glass.

This happens as hands are separate objects. Your glass should be an extra face, as is the inset in the example below.
Besides, you write 'glass' but put no Glass or at least Transparent shader node. And in your node setup you connected Color and Fac sockets which is wrong as Fac is non-color data and cannot be connected with Color. Also Shader goes exclusively with BSDF. Color connects only to Color. And Diffuse shader goes just before Output. Do some reading before you start using nodes.

Sorry, I should have included the node for the glass as well because it's not in the post so I'll add it in. For the extra face, did you mean I should extrude another face and make it glass and not a separate object?
Also, for the node socket, I just had a read of the official documentation and they are apparently all valid connections because the data they are implicitly converted under the hood like color data being converted to greyscale (color -> fac).

@Tengo 4390: in your case select the rim circle edges, make a face and apply glass  to it.

Just tried your method and the problem still persisted but I have found that the problem was screen space reflection being turned on for both the body and watch. Thanks for the help and useful info though.


text:
Is it possible to bake fluid simulation into blend file?
Is it possible to bake a fluid simulation into a blend file, instead of a separate cache folder?
The main reason is, I'm using a renderfarm to upload animation files. The renderfarm only accepts packed blend files and no external folders. I understand it's possible to bake a cloth simulation into a blend file, but not sure how to do the same for a fluid simulation.
Any help will be appreciated.

Not that I know of. Fluid caches are so big I'm not sure if this would be practical?

It depends on the renderfarm you use, ResPower has limited support for fluid simulation see https://www.respower.com/blog/?page_id=193 it also states that packing of a gluid cache isn't possible.

yes, you can export the simulation as an object sequence

No, this is not possible currently.
I'm not sure how practical this would be, given the massive size of fluid caches.
As mentioned by stacker, ResPower supports fluid simulations to some extent.


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How do I prevent hair flickering in Cycles?
I'm working on a scene for a short film, and one of my characters uses Cycles strand rendering for hair. When I render out the animation, I notice the hair flickers like crazy and I'm not sure why.
Here is the video: https://www.youtube.com/watch?v=oF662SBlZpo
Here is the node setup for his hair:

This becomes VERY apparent when the character is moving and not so much when he is still.

Does the hair flickr without shading? Could be a hair dynamics issue and not a rendering issue.

I'll do a test without shading. Also, I haven't enabled hair dynamics for this scene.

Probably too high stiffness in hair dynamics.

@Bithur The OP says there are no hair dynamics enabled.

I was just thinking, maybe it is caused by Z-Fighting of the particles, if you have children enabled, then try disabling or decreasing the number. Also be sure it is set to Interpolated.

It could be your UV coordinates, which are "generated". Since they are probably calculated in world coordinates, moving the object also moves the UV coordinates. It could cause shimmering "noise".
I don't think your node set up is what you want really. You should use the hair BSDF shader. Put 2 nodes using hair BSDF, one for reflection (hair color), and one for transmission (hair translucency). Mix between them and you are done. Consider creating manual UV coordinates and not using generated ones.
Good luck!

Thanks @beiller! Changing from "generated" to "UV" did the trick for me!

Cool good to hear! Keep in mind that it may change the way the hair colour is distributed. Happy Blending!


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Blender geometry nodes minimum bounding box or longest edge vector
NOTE: I've updated progress at the bottom of the question, so some of my initial issues have been later resolved.
I'm trying to create a Geometry Node group that applies a square cutout pattern to objects (flat plates). So far, I have managed to create a static pattern that works fine if the object is aligned with the global axes, but it doesn't work if the part is rotated.
What I (believe I) need is a vector that describes the long edge of the part. From this, I can find the rotation angle. I tried the bounding box node, but that gives me a box that is aligned to the axis, not one that represents the minimum (smallest) bounding box for that shape. I could also extract the longest edge, but I'm not sure how to do this either.
EDIT: I should add, the geometry is imported from CAD, so I believe it is similar to moving and rotating an object and then applying transformations.
I have added an image to better explain the two bounding box methods. Blender's Bounding Box node uses the axis-aligned method, whereas I need an object-aligned method - that is the smallest box that will fit around the object.
Any suggestions?
Example shapes (x2) aligned with axes - the geometry nodes work fine here:

Example shape, NOT aligned with axes:

Geometry Node Setup:

Bounding Box example:

EDIT: Strictly speaking - the original question (minimum bounding box or longest edge vector) has been answered (and accepted), however, it has prompted further questions. Please let me know if these should be split off into a separate SE post.
Following on from quellenform's response, I've made further progress. Here's what I've changed.

The convex hull node was useful for determining the rotation angle, but the longest edge calculation needs to be defined from the aligned bounding box, since the longest edge of the original shape may not correspond to the longest dimension (consider an equilateral triangle shape - the height is greater than any single side). To solve this, I used the rotation angle, to rotate the original geometry, apply the bounding box, then extract the longest and shortest sides.
New Problem - The longest edge may be a mesh diagonal, not a sharp edge. How can I filter the longest edge calculation to include edges with an 'edge angle' over some threshold?
New Problem - The rotation angle calculation for some objects needs to be calculated to the X axis, whereas for other objects it needs to be calculated to the Y axis. How can I automate this selection?
New Problem - The origin point for the original geometry is not always centred on the bounding box. To correct this, I've calculated a translation vector based on the aligned bounding box of the original geometry and the bounding box of the grid. This seems to work, but in many case it aligns close, but not exact. How do I resolve this?

Summary:

How do I filter edge calculation for sharp edges only?
How do I automate the axis selection for angle rotation?
How do I correct the translation for the grid?

File Upload:

This is an updated example file with many more sample shapes and updated geo nodes tree.

Maybe helpful: https://blender.stackexchange.com/a/274008/145249

This appears to be using the standard blender bounding box node, which is axis aligned. I need it to be the minimum bounding box (object aligned). Once we get that, then yes, I could work with the rest of your example.

Edited to explain the bounding box types, and that this geometry has been imported from CAD.

Stupid question: Why don't you create the geometry unrotated, then add your Geometry Nodes, and rotate the object only at the end? Or you create the mesh unrotated and rotate it via Transform, because with that you could read the rotation.

"What I (believe I) need is a vector that describes the long edge of the part." - this is the key information here: do you want the bounding box to be defined (aligned with) the longest edge? In the examples provided, it does satisfy your ultimate goal, which I interpret as "wrap in the smallest possible rectangle". Otherwise you want to research machine learning and use Python instead. Well, Python probably already has a library figuring out the problem.

@quellenform - The geometry is imported from CAD - this is one piece in a much larger model.

@MarkusvonBroady - That's right - but they only work if the model is already aligned with the global axes.  You'll notice in the image above, that the mesh appears to be rotated (transformed), but this is in fact the definition of the mesh without a transform.

...I would suggest you create a follow up question from your added changes, otherwise it goes beyond the scope and this question loses focus here.

TL;DR
The node Convex Hull creates the outer hull from a flat rectangular shape, which is also the object-aligned bounding box.

The following setup should get you there, assuming that:

The mesh is flat
The mesh is rectangular

To start, I use the Convex Hull node, which gives me back the original outer shape:

Then I remove the extrusion of the mesh so that I get a single rectangular (upper) face. I achieve this by comparing the normals of the faces with the upvector:

Then I separate the two longest and the two shortest edges from each other and determine their lengths:

By transferring the lengths of the first edge in each case (index $0$) with Sample Index, I can process this information further and use it to calculate the grid and the size of the cubes. After I have created the required objects from these values, I determine from the vector of the longest edge and with the help of Align Euler to Vector additionally the rotation that I need to align these objects correctly. Then I simply instantiate the cubes at the points of the grid:

And the final result looks like this after Mesh Boolean:

(Blender 3.6+)

Update
If the points of the upper surface are not exact on a plane, the node Convex Hull may add an additional diagonal edge.
You can avoid this problem by either editing the mesh and making sure that all points are exactly on one plane (select the points of the upper face in Edit Mode and press S >  Z > 0), or you can either move the points there in Geometry Nodes, or remove the extra diagonal edge.
This might look something like this:

This is great. It seems to be tolerant of object shape (trapezoid, triangle or irregular polygon instead of a rectangle), but it seems to be intolerant of orientation (direction of the long edge). I think I've traced the problem to the 'Align Euler to Vector' node. The grid that was constructed was not always aligned with the base object. I'm not sure how to resolve that though - any suggestions?

@G.H. After all, your example only shows a rectangular mesh. What other shapes are there? For this, it would be good if you shared your blend file (https://blend-exchange.com) so we can take a closer look and possibly supplement the question with more information.

The shape is fine, but the rotation of the shape seems to have a problem. Here's an example with a rectangle that has the problem.
https://blend-exchange.com/embedImage.png?bid=MKjGg7AR
For what its worth, the model is representative of a rectangular sheet of material which may or may not have cutouts - which means there is a maximum size (rectangle) but any shape (polygon) smaller than the original rectangle may be valid.

@G.H. Ah, all right, that has to do with the fact that the points of the upper face are not exact on a plane. Select all four points of the upper face in Edit Mode and scale their Z-position to 0 (S > Z > 0). If the points are not exactly on one plane, the node Convex Hull will create an additional diagonal edge (which of course will be the longest edge of the mesh), and therefore you will not get a correct rotation.

I've accepted this as the answer because the answer lies within your blender file, however, your description is oversimplified. The process I used (with your help) was to calculate the longest edge and its rotation angle, then use this angle to rotate the original geometry, calculate the bounding box (since its now aligned) - this gives me the length and angle of the longest edge and the dimensions of the aligned bounding box.

Additionally, The convex hull still appears to generate internal edges in some cases, so the longest edge should be calculated off the 3d convex hull shape without deleting faces, but with considering the edge angle. I'm not sure how to do this practically - could you offer advice? Or let me know if I'm better off raising a new question.


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Plane/Face from Coordinates using geometry nodes
I'm trying to create a solid mesh from a set of planar coordinates. I've tried a bunch of things, but only 2 methods have got me close to the desired result.
Method 1: I tried to add in a quadrilateral curve using 4 points, then converted that to a mesh, but the mesh is edges only, no face - I'd like to continue this method, so if there's a way to fill the mesh that would be great. The FillCurve node only works with Z=0.
Method 2: Create a Grid with 2x2 vertices, then modify the location of each vertex - this worked, but is way too convoluted - an easier method must exist.
The image below shows the two methods.

Any suggestions?

nope, there is no easier way, except you use animation nodes or something else. But of course you could use the curve thing, if you first create your coordinates in that way, that z=0, then use fill curve and change the "missing" values afterwards or rotate/move/scale it, that your coordinates fit.

Curve to Mesh with Curve Line and Quadrilateral as profile ...?

I Tried this option - the problem is that the coordinates are not orthogonal, so I need to calculate the normal vector for the direction of the Curve Line, and to do that, I need a face, so we're back to the original problem

Since you could not achieve a solution with Curve to Mesh in your case, the following setup might help you:

Here I create a curve with Quadrilateral, which allows the comfortable definition of the four corner points.
But I use this only as a container from which I transfer the positions to the corner points of a grid.
In the next step I extrude this grid, flip the original face and merge the two resulting objects with Merge by Distance.
If I understood the question correctly, this should be exactly what you are looking for.
(Blender 3.2+)

Thanks - that's basically the same as my second attempt, but much neater. The Transfer Attribute and Set Position Nodes make it a lot less complicated!


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UV Unwrap at 1:1 scale?
I'm trying to unwrap a few faces of my model at 1:1 scale to fit onto an image that I've prepared to be 1:1 scale as well.  Everything I've tried has resulted in a distorted unwrap one way or another. The closest result I've found is to unwrap with Cube Projection - that seems to keep the relative locations of the face correct, but the X and Y scale needs to be manually tweaked.
The desired result will have the X and Y scale at 100% of the original (or at least X and Y will be the same), and the relative positions of the faces need to be the same as the original.
In the image below, the Y scale has worked OK, but the X scale is compressed.
I tried the "World Scale UV" tool of the 'Magic UV' add-on (suggested in a similar question), but I couldn't get a useful result from that.
All transforms and scales have been applied. I don't know if it's relevant, but the original geometry has been created via geometry nodes and modifiers that have since been applied.

I've attached the blend file from the image above for reference.

EDIT:It just occurred to me that my model isn't directly on the XZ or YZ plane, so the UV wrap could just be a projection of the faces to one of those planes - is that the case?
CLARIFICATION: When I say 1:1 scale, I mean that the image is the correct dimensions for the intended geometry. i.e. the height and width of the image matches the height and width of the geometry. I'm NOT referring to an aspect ratio of 1:1 which seem to be the understanding.

By default, the UVs are represented in a UV canvas that is 1:1 (square) if you use a image that is not 1:11 like 1:2 ( example size: 512X1024) the UVs are going to mapp itself into that new aspec ratio, so the same UV's are going to look shorter or thinner depending on the aspect ratio of the image. the recommendation is to always use a 1:1 aspect ration like 1080X1080 2048 X2048 and so.... for your images to avoid this visual distortion in the UV editor.

Ok, so I want my model faces projected on to my image without any mapping out distortion. E.g. a model faces that is 1000px wide by 2000px tall appears in the UV editor the same dimensions. Will adding black space either side of my image to make it square help? (I'm on my phone, will test it later)

Folowing up on the suggestion of using a texture image with 1:1 aspect ratio - this did solve the problem of UV faces being distorted in the X direction (i.e. my X and Y dimensions were proportionally correct), but it didn't help with the overall scale (i.e. my UV faces were still much smaller than the image - which was sized to match real life (e.g. 1:1 scale not 1:1 aspect ratio). I can't find anything to suggest that the UV faces can be sized 1:1 (1 model unit = 1 UV unit).

Technically, your UVs seem correctly unwrapped. The issue is the texture you are using isn't 1:1, it is narrower on the X axis. The UVs occupy all the texture space from 0:0 to 1:1 no matter the texture.

The simplest solution would be to edit your texture image so that it is a perfect square. Let your texture info on one side, and use the remaining space for a different texture, it's actually better in render speed this way.

What do you mean by my texture being narrower on the Y axis? The texture was created from dimensions taken from Blender. In any case, if you refer to the image in my original post, the X axis is clearly narrower on the UV than in the model (as shown by red arrows).

Erratum, narrower on the X axis. The UV space is to be considered as a grid that defines how your mesh is unwrapped on it from left to right and from top to bottom. When your texture isn't square, it will still read from left to right and from top to bottom, except now your texture is narrower on one axis, so the UV follows that. That is why you should use square textures all the time when mapping with UVs.

If you look at the first screenshot, you can see the difference between your texture size and a square texture size. The UVs are the same, only the texture is different.

As Lolock says, your image is not square (1:1 aspect ratio), by default it will squeeze the UV when you'll unwrap it. To avoid that, either use Lolock's solution or keep the Image Texture node selected when you unwrap, it will keep your UV at its good proportions.

Hi, I don't understand what you mean when you say my texture isn't 1:1... perhaps we have a different definition? When I say 1:1 I mean the scale of the image texture exactly matches the real scale in real life. NOT the aspect ratio (It sounds like that's what you're implying?)

Yes I mean the aspect ratio

Thanks for the help, but that's not what this problem is about.

I was trying to address this problem: "the X scale is compressed". If you select the Image Texture when unwrapping, the X should not be compressed. Is it not your problem?


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Follow Path: Set start point?
There's so many related questions i may have missed something. But i'm trying to set a series of existing objects that start with a pre-defined location. I want them to follow the same curve - but with zero offset.
Consider the example below - The first cube starts on the curve start point, but the second point is offset. I have many more objects offset further.

When I animate further, the second (and subsequent) objects are offset by their initial distance from the start point.

What I want is for the object start point to be offset, but to follow the path strictly. That is, follow with zero offset.
I also don't want to create multiple curves if I can help it.
Any suggestions?
EDIT: To clarify - the objects are converted CAD objects, so the start position is pre-defined. Calculating offsets for each object isn't practical, so what I'm looking for in a sense, is a way to automatically calculate the offset, or achieve a similar result some other way.
EDIT: Added sample blend file. Note - One object has a follow path constraint added, with a manually tweaked offset.

Suggestion.  Make the  single curve longer.  The items have location(0,0,0).  The items start at different offsets on the curve such as [0.0, 0.1, 0.2]  You may want to use Python scripts or Python drivers to coordinate motion and object visibility. Please show your work if you so choose.

Location means what you see in the object panel.  Location Scale Rotation are near each other in the panel.

You can use drivers for this.
Use this scripted expression here:

the "-.5" is basically the offset of the objects.
So for the next object use "-.4", then "-.3" and so on. (or whatever you like).
result:

or, if you are as lazy as hell as i am, you can write a python script which takes much more time to figure it out than to do it manually for 100 objects but then you could do it for 10000 objects in no time, you could do this:

Create a new collections, name it "Cars".

Create one object which should follow the path, give it this follow path constraint:

with this driver:

The object for the var should be the object itself.
it will throw an error because the custom property isn't defined yet - don't worry.

Now copy that object as often as you want - all objects should now be in your new collection.

run this script:
 import bpy

 def update_dependencies(ob):
     def updateExp(d):
         d.driver.expression += " "
         d.driver.expression = d.driver.expression[:-1]
     try:
         drivers = ob.animation_data.drivers
         for d in drivers:
             updateExp(d)
     except AttributeError:
         return

 for i, ob in enumerate(bpy.data.collections["Cars"].all_objects):
     ob["number"] = i
     update_dependencies(ob)
     print(i, ob)

This script creates a custom property called "number" for each object and assigns a unique value to it (0,1,2,3...), then it updates all drivers.
Run the script and enjoy:

Thanks for the reply - but this still relies on having a start offset. My objects have an existing position (converted CAD geometry) - In a way, I'm looking for a way for Blender to automatically (or python-matically) calculate the offset so the original object position is maintained.

@G.H. That's an information you should have given from the start ;) Sometimes simplifying a problem leads to incorrect answers, since the solutions can differ a lot depending on the exact problem or task you want to achieve.

I used the term "existing objects that start with a pre-defined location", but I could have emphasised that point more.

@G.H. True, I've read this but wasn't sure what to do with it. I guess that's what also fueled the first comment under your question that the items must have the location (0,0,0) to follow the path correctly. You have to keep in mind that we might know how to work with Blender, but we are not familiar with the different projects and what premise each of them has. Thanks for your clarification in this case.

Suggestion.
Curve can be made longer to have different starting position visuals.  All objects with Follow Path constraints can have location (0,0,0) in the object panel.  The follow path constraints offset factor will have different values at their starting movement frames. Example starting offset factor .. x element of [0.1, 0.2, 0.3].  Use Python if that suits you.

There is no need to create other curves or make the curve longer, no need for Python or drivers etc. I guess the way you are using it might be wrong.
First of all, to have the cube follow on the curve, it has to be cleared from any location transformation - so press Alt+G to set it back onto the world's center.
Now to place it behind the other cube, change the Offset value in the Follow Path constraint to a positive value. You don't have to make the curve longer, the cube will just be moved straight in the elongated direction of the curve. Here are three cubes on a curve, one with offset 0, the next offset 15 and the third has an offset of 30:

So you might wonder why the offset is a positive value to move out of the curve and why moving along the curve needs negative values to get to the end. Also it doesn't seem as if the values 15 or 30 represent any distance in Blender units which the cubes are offset.
The reason is the following: if you now select the curve and look into the Curve Properties, there you will find the Path Animation options. By default the settings are Frames = 100 and Evaluation Frame = 0.000 which means, and object needs 100 Frames to travel from start to end of the curve. And the Evaluation Time at 0 means, you are now at the starting point. And there is the cube with Offset = 0.

To see what the offset now actually means, I change the Evaluation Time value at first to 100. As it was to be expected, the first cube is now at the end point (I've enabled X-ray mode to see through):

But if I now set the Evaluation Time to 115, the second cube is at the end point of the curve - this the offset 15 that is set in the constraint. The third cube will then reach the endpoint at 130 because of its offset 30:

How far the distance of a cube with offset along the curve is depends on two values: the Offset in the Follow Path constraint and the Frames value in the Path Animation settings of the curve.
For example, if I change Frames from 100 to 20, the three cubes are much further apart from each other although I didn't change the Offset values in the constraint:

The reason is, since they only need an Evaluation Time of 20 to get from start to end, they need to be much further away to keep the time offset of 15 and 30. So with Frames = 20, at Evaluation Time = 20 the first cube with no offset reaches the endpoint:

And like before, the second cube reaches the end at Evaluation Time + Offset, that's 20 + 15 = 35, and the third at 20 + 30 = 50:

This means, to move the cubes along the curve you can use Path Animation in the Curve Properties. By animating the Evaluation Time you move them along the curve simultaneously, keeping the distance that's given by the offset value. If you want them to move at different speeds you can additionally animate the Offset values in the constraints.
Animating the Evaluation Time however is a bit tricky. It gets animated when you click on Animate Path in the constraint settings. In this moment, it gets an F-curve Modifier which uses the Frames setting to determine the linear movement.
If Frames is set to 100, this means that the animation will start at frame 1 and at frame 1 + 100 = 101 it will reach Evaluation Time = 100, the end point of the curve. Of course you can modify this later on, but it isn't as obvious as standard keyframe animation at first.
Here's for some examples. You might not be so flexible with the F-curve Modifier as with keyframes, but you can do some fancy stuff as well. First the basics, the initial animation that is created gives a linear movement using this formula:
$$y=a\cdot x^1+\text{ coefficient}$$
with $a$ being the value you enter in the $x^1$ field, which is the multiplier for the frame number $x$ and of course the coefficient which is entered in the according field. The resulting $y$ is the Evaluation Time.

This standard linear motion looks like this:

If the linear motion is too boring, you can for example set the Order in the F-curve Modifier to 2. Now you can have a quadratic equation for the motion, in my example I used this formula:
$$y=0.01^2-0.01$$

This results in a slowly speeding up motion:

If you want to be more crazy, you can also animate the influence of the constraint on the cubes. I've done this for the third one in this example. It starts with a constraint influence of 0, which let's the cube sit in the world center. With increasing influence, it starts to move towards the curve.

Yes described earlier, the cube has to be in the world's center to make sure it sits on the curve instead of moving some away from it.
But what if you don't want the cube to start from the center? You can use a Copy Location constraint and have it attached to some empty for example. Then you keyframe the influence on this constraint. At first with an influence of 1, the cube stays in the same location as the empty. With a decreasing influence it moves back towards the center. If you now increase the influence of the Follow Path constraint, it moves from the empty back onto the curve. This can look like this:

//EDIT: As you've explained in the comments, your cubes sit at locations off the center initially and you need to get them onto the curve. Instead of having cubes in the world's center and letting them start from empties at different locations, you can do it the other way around. The good thing is, you only need one empty for all cubes since they all have to end up in the world's center.
In this example, there is an empty at (0,0,0) while two cubes have original locations off the center, one at (-10,-10,0), the other at (5,-8,0). Both have a Copy Location constraint targeting the empty and start with an Influence of 0, slowly increasing to 1 which pushes them into the world's center and therefore onto the curve:

This is a huge answer - kudos for the effort! However, it doesn't really solve the problem. I know I can use an offset, but the key part of the problem is the pre-existing position. In my case, it's geometry converted from a CAD model, so the start locations are defined, and not easily converted to "offset" values.

Well, at the end I gave an example where you start with an offset given by the empty and with decreasing influence the cube moves to the world center, and therefore sits correct on the curve. You can do it the other way round, the cube sits on its original location and an empty is in the center. Start with influence 0 and increase it to 1 to get the cube in the center resp. onto the curve. The advantage is, you can use one empty for all cubes, no matter where they are. To get this automated I'm not the right person.

Hmmmm... so if the empty were aligned with the start point, that might have the desired effect... I'll look into that more.

@G.H. Maybe I'll edit an example at the end of this answer.

Have a look, that's what I meant. For automation processes I guess @Chris will be more suited since he is better at drivers and python than I am.

This might be on the wrong track.. but would this GN group help?
It takes a collection of objects along X, (each with their own origin) and pushes them down the modified curve-path by Offset, disappearing the objects when they go off either end.

.. for this behaviour:

.. which may need tweaking to your requirements.. call back, if this looks like a possible way to go.

This could work... It would require setting a time start point offset such that the blue cubes are all on the line in the same arrangement... E.g. rather than starting at frame 0, start at (say) frame 50...

Hi @G.H. ! I'm not clear on what your input geometry might be... CAD-derived objects with their own origins? Aligned? You could offset objects by f(Index)  ..Share a sample if you like, on https://blend-exchange.com/


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Blender crashing when opening files
I recently installed Blender 3.2.1, and immediately I noticed that, when opening previously created files Blender crashes, no error messages or anything - just gone. I rolled back to 3.1 and had the same problem (previously worked ok), I've now tried 3.3 alpha as well and I get the same result. This happens on almost all files - I've noticed that SOME of the autosave.blend files will open OK.
the link below is just a basic stage that I use, with a background, couple of lights and a camera - even that crashes.
Basic Stage.blend
EDIT: I just noticed that if I try to open a file it will crash - if I try the same file again immediately it will (maybe?) work.
Any suggestions?

Please don't post external links to blend files. You can upload your file to https://pasteall.org/blend/ or https://blend-exchange.com/help as long as you paste the link to it into your question. I've looked at your file with Blender 3.2.1 and it loads fine, but the camera Clip Start is set to such a low value that it's causing flickering in the viewport when you try to move the cylinder.

It causes flickering and also makes the navigation controls go nuts. The clip end is also one zero too much. It also probably doesn't help that your objects are big, like your cylinder 50 meters high and 100 meters long/large. I guess you change your clip values at some point because you had some display issues maybe, but instead you should check your object's scales before changing these.

Hi :). Works just fine here, Blender 3.2.

Thanks for the general tips.
I'm now suspicious of a registry problem. I have a similar issue with a different program that needs to update the registry when opening if changing versions. That program freezes without crashing, but a second launch works for that program too.


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Geometry Nodes - Edge Fade, Distance Decay?
I'm trying to replicate an effect that I created in Grasshopper. its an edge fade, where my pattern (in this case a sine wave) fades according to some profile when it is within a set distance from the edge of the mesh.
I've created a sin wave with distance decay/fade, but I don't know how to reference the edge of the mesh in geometry nodes.
The solution should work for irregular surfaces, or surfaces with holes in them too...
I'm using Blender 4.2 in case that matters.
Any suggestions?

Do you try a Vertex Group to tag the edge controlling the decay ? Is it always a strait line ?

I eventually figured it out. I was trying to seperate values that were higher or lower than some edge distance value, but it turns out the 'from max' value of the map range node effectively does that for you.


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Why is part of my weight paint not being erased?
Working with some controllers in my rig and trying to disconnect them from the mesh. The weight paint subtract mode works for other weight paint, but the toes just refuse to be erased. It stays red and connected to the bone, when I want it to be blue and disconnected, since I want a different bone to control it
I recorded what's happening so you can better understand: https://youtu.be/aOkRekrE2Hw
https://pasteall.org/blend/e511a099ae87479fa9d1ca0176fe26f4

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

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

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

Are you using autonormalize?  Are the verts in question weighted to any other bones?  If yes and no respectively, you can't subtract, because there is no other group to autonormalize the weights.

@Nathan Just unchecked autonormalize, and i was able to erase the red. That cause other unforeseen problems, but I'll continue to troubleshoot on my own. Thanks for the help!


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How do I mask whole cells in a Voronoi texture?
I'm trying to overlay a Voronoi noise texture in Blender, I'd like it to blend into another texture with fewer and fewer whole cells across a gradient. I've tried two methods but neither quite gives me what I want.
Method 1: Use a gradient texture and ColorRamp

This almost works but a lot of the cells are now cut in half because they now have a gradient across them and the color ramp is just doing its job.
Method 2: Adding the gradient texture then clamping

This is much closer the effect I'm after but there some holes in the Voronoi side and some cells are still cut.
I know you can use position output of the Voronoi node to filter based on cell centre coordinates but is there any way of thresholding based on the colour at the centre of the cell?
Any ideas on how to proceed greatly appreciated.
EDIT: The effect I am trying to achieve looks very close to the bottom image but without the holes in the top of the white region.

I want to avoid the consistent horizontal cropping that occurs with the gradient texture method. I've highlighted some examples in the above image.

can u please show us a end result sketch or picture what you want to achieve?

you can mask out pretty easy like this:

but i have no idea how you want to blend out this to another (what texture?) and how it should look like.
But maybe this already helps you.
or do you mean like this?

Thanks, I want to Blend it over another texture like the second image. Trouble is I need to control the blend with textures not position as it needs to be on a larger model more complex model.

so please improve your question with a sketch/image, how it should look like. Thanks.

Is this it? (the squares show the accumulated output of each node)

Your texture-space.. (could be UV, or Generated.. etc.)
Sample the texture-space at the 'Positions' of Voronoi cells
Sample some other texture at those positions
Put through a threshold to create a mask

This is ideal! I can still control the edges with a texture but using the position vector in this way allows me to control whole cells in the Voronoi.


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Can't seem to rotate bones with IK on model?
I'm trying to curl my rigged hand models finger by rotating or changing the position of individual bones. Bone rotations or transformations are only deforming the model and the IK doesn't seem to be forcing the bones to follow along naturally with the transformations/rotations of another bone.
Is this a problem with my rigg?
EDIT: Rigged model comes from https://github.com/leapmotion/leapjs-rigged-hand/blob/master/models/Game%20Quality%20Hand/Arm:Hand/Leapmotion_Basehand_Rig_Right.fbx


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Is Offset Edge feature removed?
I cannot find the offset edge feature anymore in Blender 3.6.1 LTS. The attached image is from the internet, representing an old version. Where can I locate this feature now?

.
EDIT: adding image as asked...

It's in the same place for me as in the image you posted. Blender 3.6.1 on Windows 10.

For me it is not there. Do we have to activate it somewhere? I don't remember.

nothing changed. it is still there in 3.6. what OS are you using? can you share a screenshot of how it looks on your pc

I edited my question to add the image. plz have a look

You need to enable the addon called Mesh: Edit Mesh Tools.


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Join two objects with perfect edge-flow at any stage of modelling?
"These are two separate objects. Now, I want to join them in a manner that enables a smooth transition between them (using bevel and subsurf). How can I achieve this without having to start from scratch and without extensive pre-planning?"

EDIT:-
THIS IS WHAT I COULD DO AT BEST. IS THERE A BETTER SOLUTION OR TOPOLOGY?

EDIT 2:-
THERE ARE DISTORTIONS IN THE REFLECTION/REFRACTION AS SEEN IN THE IMAGE BELOW. IS THIS DUE TO TOPLOGY AND WHAT WOULD BE THE FIX TO IT?

You can boolean then correct the topology a bit, what difficulty have you met?

you always have to edit it manually to fuse together nicely. or you can easily just do a remesh.  Quad Remesher is pretty powerful.

@moonboots Yes, that is the approach I took. However, I find it difficult to match the number of vertices on one shape with that of the other. Additionally, when I add loop cuts (Ctrl+R), it tends to distort the shape by adding extra geometry.

@HarryMcKenzie I gave the Trial version of QuadRemesher a shot, but to be honest, it left me feeling frustrated and disappointed. First and foremost, it came with an exorbitant price tag, which was disheartening. And when I eagerly hoped it would work its magic and create the geometry exactly as I wanted, it let me down. Instead of achieving the smooth and precise results I was aiming for, it decided to add these infuriating non-straight lines on a perfectly flat surface. It was beyond aggravating!

what you show seems ok, anyway does it give the result you wanted?

@moonboots There are distortions in the refraction in the glass. Is this due to topology? And is there a fix to it? (Image added to my question above)

could you please share your file?

@moonboots yes, but how?

Use https://blend-exchange.com/ or another platform

@moonboots

it looks like it's the reflection that it is supposed to have with this topology, if you want something less round, you probably need to add a support edge loop? https://zupimages.net/up/23/30/rd59.jpg

@moonboots Indeed, when I introduced an additional edge loop, the reflection exhibited a distinct wave pattern. This behavior seems to be directly influenced by the topology. Furthermore, to address the issue of jaggedness, I increased the subdivision level from 2 to 6. Thanks for your time and help.

Please don't write in all caps in the title or body of any posts, it is the written equivalent of shouting, is harder to read and may be considered rude. Please use the [edit] button below the post to change you text into regular case.

It's caused by your topology, it is round so it makes the reflection look round. Add a support edge loop in order to sharp the bottom edge of your vertical shape:


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Fresnel node and get an equidistant shading?
Is there a way to use Fresnel node and get an equidistant shading around the silhouette from any angle of rotation? Right now it is darkest at the point closest to the camera. I want it uniformly shaded around the silhouette of the shape.

I think not. Fresnel is a function of surface normal and view-vector, so is not inherently related to silhouette at all. Would any of the (post-view-transform) , 2D effects work for you? (Freestyle, Line Art, compositor methods  )

@RobinBetts Ok. If not Fresnel then is there any other way? I need the silhouette OR the border of a shape (any random shape) colored with a gradient which gradually fades towards inside of the shape.


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Pinching issues
How do i model these 2 shapes (a sphere and a slightly flattened sphere) so that there are no corners visible? This image cant show the topology errors but trust me there is. 2 corners when subdivided gives such small bumps in 4 corners.

These are the corners that creat bumps after subdiv modifiers

You could give your sphere a Shrinkwrap modifier and use a UV Sphere as target?

@moonboots no but my object is to make the other slightly flattened shape also shrinkwrap thru uvsphere will have top n bottom pinching

Use UV Sphere, and position poles on the middles of the flattened areas. That is, flatten the UV Sphere vertically.

@MarkusvonBroady ok!


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Video with alpha channel from Blender not showing transparency when imported into VSE
I was experimenting with Blender to create a custom video transition with a transparency layer using the general 3D design tools. I was able to output a video with a transparency layer which I tested on a website to confirm that the video shows transparency (rotato.app) which showed that the video had and transparent background.
EDIT: I've discovered that the issue is with the previewer in VSE. This shows the transparent layer as black but when I render the video with my transition then everything renders with the transition sequence being transparent where it shows black. Does anyone know why the previewer isn't showing alpha layers properly? I have selected 'Colors and Alpha' as display channels on preview.
When adding this back into Blender in the VSE the transparent parts of the video are showing as black. I have tried using 'Alpha Over' in the strip Blend mode and have tried different formats when rendering the video (from QT to PNG to FFMPEG #1) but no matter what I try I still get black where the transparent areas are supposed to be.
The only thing that has worked is outputting a series of PNG images and importing them as an image sequence into VSE.
Is this a bug in VSE or am I doing something wrong? I've tried looking at the video strip settings and playing with that but I can't seem to get the transparency layer to work. I searched for answers and couldn't find anything specific to my issue where I'm using Blender to create the video with RGBA and it still doesn't work when importing to Blender VSE.
I am using Blender version 3.0.0 with an M1 Mac.

if u provide a blend file, i will check it out

Thanks for the offer! I've found that the issue seems to be with the previewer only. When I render the file then everything renders as expected. Not sure why the previewer doesn't show the transparency in the video strip?

you can write your own answers here, if you want to. Then other people can read it too and can find the solution ;)

If one deactivates the Use proxies feature in the View Settings, the preview shows the alpha blending as expected.

Hello and welcome. This site is not a regular forum, the answer section is reserved exclusively for answering the OP question. To ask for clarification, post comments or replies please use the comments section instead. If you have the same problem or a different question please use the Ask Question button at the top right. If you want to add additional information or further developments, use the edit button below the original post instead. This post may be removed or converted to a comment.

Your answer could be improved with additional supporting information. Please [edit] to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center.


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Define the fbx file name : collection or active object name with a checkbox
I try to create this script but I’m newbie in python

The aim is to export a fbx in specific folder when you click Export button.
If the checkbox is True, then the filename get the name of collection. Conversely, if is uncheck the the filename get the active object.
Here is my own script but i get an error message which says name ‘filename’ is not defined.
Thanks for your help.
bl_info = {
    "name" : "MyTab",
    "author" : "",
    "version" :(0, 1),
    "blender" : (2, 93, 6),
    "location":"View3D > Tool",
    "warning":"",
    "wiki_url":"",
    "category": "Custom"
}

import bpy
from bpy.props import BoolProperty

bpy.types.Scene.my_checkbox = BoolProperty(
    name="is Collection",
    description="is Collection ?",
    default = False)

class MyPanel_PT_Panel(bpy.types.Panel):
    bl_label = "MyPanel"
    bl_idname = "my_panel" #id name du premier panneau
    bl_space_type = 'VIEW_3D' # le type d'espace c'est à dire espace 3D
    bl_region_type = 'UI'  # ca agit sur quoi ? sur l'UI
    bl_category = 'MyTab' # nom de l'outil qui sera affiché sur les onglets tools

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

        row = layout.row()
        layout.prop(context.scene, "my_prop")
        row = layout.row()
        row.operator("fbx.exporter",text="Export")

        if (bpy.types.Scene.my_checkbox == True):
            fileName = bpy.context.collection.name + '.fbx'
        else:
            fileName = bpy.context.active_object.name + '.fbx'

class Fbx_Exporter(bpy.types.Operator):
    # export in a Substance Folder for Stone project     # Use this as a tooltip for menu items and buttons.
    bl_idname = "fbx.exporter"        # Unique identifier for buttons and menu items to reference.
    bl_label = "fbx_exporter"         # Display name in the interface.
    bl_options = {'REGISTER', 'UNDO'}  # Enable undo for the operator.

    def execute(self, context):        # execute() is called when running the operator.

        # Get the selected objects
        selectedObject = bpy.context.selected_objects

        # Get the name of selected object
        for obj in selectedObject:

            # to define folderPath
            # rajouter trjs \\ pour définir un chemin

            folderPath = 'C:\\Users\\Username\\Desktop\\FbxFolder\\'

            # customfilePath will be used to filepath of FPX API operator
            customFilePath = folderPath + fileName

            # FBX API operator

            bpy.ops.export_scene.fbx(filepath= customFilePath, check_existing=True, filter_glob='*.fbx', use_selection=True, use_active_collection=False, global_scale=1.0, apply_unit_scale=True, apply_scale_options='FBX_SCALE_UNITS', bake_space_transform=False, object_types={'ARMATURE', 'CAMERA', 'EMPTY', 'LIGHT', 'MESH', 'OTHER'}, use_mesh_modifiers=True, use_mesh_modifiers_render=True, mesh_smooth_type='OFF', use_subsurf=False, use_mesh_edges=False, use_tspace=False, use_custom_props=False, add_leaf_bones=True, primary_bone_axis='Y', secondary_bone_axis='X', use_armature_deform_only=False, armature_nodetype='NULL', bake_anim=True, bake_anim_use_all_bones=True, bake_anim_use_nla_strips=True, bake_anim_use_all_actions=True, bake_anim_force_startend_keying=True, bake_anim_step=1.0, bake_anim_simplify_factor=1.0, path_mode='AUTO', embed_textures=False, batch_mode='OFF', use_batch_own_dir=True, use_metadata=True, axis_forward='-Z', axis_up='Y')

        return {'FINISHED'}            # Lets Blender know the operator finished successfully.

def register():
    bpy.utils.register_class(MyPanel_PT_Panel)
    bpy.utils.register_class(Fbx_Exporter)

def unregister ():
    bpy.utils.unregister_class(MyPanel_PT_Panel)
    bpy.utils.unregister_class(Fbx_Exporter)

if __name__== "__main__":
    register()

you are defining filename in the panel class, where it remains a local. That means it is not visible in the operator class. Create a string property attached to Scene and use it in both classes.  or,more simply, move the if statement to the exporter class.

Three important points that should be changed:

As mentioned, the export operator needs the filename (line 36 in following script)

Access to registered properties in scene with bpy.context.scene.my_checkbox (line 51)

You export the same object several times, according to the number of your selected objects (line 62). No need for this cause bpy.ops.export_scene.fbx(use_selection = True) by default

And a few little things more directly commented in the script.
bl_info = {
    "name" : "MyTab",
    "author" : "",
    "version" :(0, 1),
    "blender" : (2, 93, 6),
    "location":"View3D > Tool",
    "warning":"",
    "wiki_url":"",
    "category": "Custom"  ### use "Tool" here if Panel should be in View3D > Tool ; no existing category = new tab
}

import bpy
from bpy.props import BoolProperty

bpy.types.Scene.my_checkbox = BoolProperty(
    name="is Collection",
    description="is Collection ?",
    default = False)

class MyPanel_PT_Panel(bpy.types.Panel):
    bl_label = "MyPanel"
    bl_idname = "MY_PT_PANEL"  ### avoid PT warning    #id name du premier panneau
    bl_space_type = 'VIEW_3D' # le type d'espace c'est à dire espace 3D
    bl_region_type = 'UI'  # ca agit sur quoi ? sur l'UI
    bl_category = 'MyTab' # nom de l'outil qui sera affiché sur les onglets tools

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

        layout.prop(context.scene, "my_checkbox") ### use prop identifier , "scene.my_prop" is not registered
        row = layout.row()
        row.operator("fbx.exporter",text="Export")

#        if (bpy.types.Scene.my_checkbox == True):              ### moved to operator, cause export op needs fileName
#            fileName = bpy.context.collection.name + '.fbx'
#        else:
#            fileName = bpy.context.active_object.name + '.fbx'

class Fbx_Exporter(bpy.types.Operator):
    # export in a Substance Folder for Stone project     # Use this as a tooltip for menu items and buttons.
    bl_idname = "fbx.exporter"        # Unique identifier for buttons and menu items to reference.
    bl_label = "fbx_exporter"         # Display name in the interface.
    bl_options = {'REGISTER', 'UNDO'}  # Enable undo for the operator.   ### undo export ???

    def execute(self, context):        # execute() is called when running the operator.

#       if (bpy.types.Scene.my_checkbox == True):    ### this calls the rna_property not the value
        if context.scene.my_checkbox == True:        ### prop 'my_checkbox' is registered in scene
            fileName = bpy.context.collection.name + '.fbx'    ### returns 'Master Collection.fbx' if active collection is 'Scene Collection'
        else:
            fileName = bpy.context.active_object.name + '.fbx' ### returns '[active obj].fbx' , e.g 'Cube.fbx'

        # Get the selected objects
#       selectedObject = bpy.context.selected_objects  ### no need cause by default bpy.ops.export_scene.fbx(use_selection = True)

        # Get the name of selected object
#       for obj in selectedObject:    ### no, this gets each obj in list ; if names: for obj.name in selectedObject:  ... but
        ### ... you export the same object several times, according to the number of selected objects

            # to define folderPath
            # rajouter trjs \\ pour définir un chemin

        folderPath = 'C:\\Users\\Username\\Desktop\\FbxFolder\\'  ### unindent next lines to execute once

        # customfilePath will be used to filepath of FPX API operator
        customFilePath = folderPath + fileName

        # FBX API operator
        ### no need to call default options again if not changed, see blue ones in API bpy.ops.export_scene.fbx()
        bpy.ops.export_scene.fbx(filepath= customFilePath, use_selection=True, use_active_collection=False, apply_scale_options='FBX_SCALE_UNITS')

        return {'FINISHED'}            # Lets Blender know the operator finished successfully.

def register():
    bpy.utils.register_class(MyPanel_PT_Panel)
    bpy.utils.register_class(Fbx_Exporter)

def unregister ():
    bpy.utils.unregister_class(MyPanel_PT_Panel)
    bpy.utils.unregister_class(Fbx_Exporter)

if __name__== "__main__":
    register()

Thank you so much for taking time to respond me.
It will allow me to improve my workflow considerably and you commentary is very clearly.
Thanks lot ! Its very precious for me.


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How do I create a Jacquard-Textile with an unrepetitive pattern?
For an ongoing project I need to create a textile object in Blender that has a jacquard air mesh. See the attached reference image (Size of fabric on ref.Picture: 100mm x 100mm). The jacquard has a non-repetitive pattern. The object has a size of 1900mm x 900mm. I do not have a photo of the final sized jacquard, so the image texture is not a good choice. All I have is an Adobe Illustrator vector drawing. Can anyone help me with this? Thank you very much and best regards Silvana

How can I define the exact position of the pattern. for example if I have a pattern like the following on the picture:

How can I increase the displacement? (the holes should be deeper)

Hi :). Where exactly are you stuck? Making the different textile materials, or applying the pattern?

https://simonthommes.gumroad.com/l/Knittr

@JachymMichal I'm a Blender beginner, so I'm struggling with both. I don't really know how to get started. I have the model built, but now I need to apply the pattern to the model. Since the pattern is defined exactly as in picture 2 of my question and I don't have a picture of the jacquard - how can I make the pattern as simple as possible using only my Adobe Illustrator drawing?

Your image seems to have three different textures in a randomish distribution.  Blender can handle this with a procedural or mixed (procedural & image textures) material.  In this example Mix RGB nodes and Color Ramp nodes use Noise Texture nodes to create masks for three separate areas similar to your image:

Here the Voronoi Texture node, Musgrave Texture node, and Magic Texture node represent the three weave patterns -- they can be replaced with appropriate image textures or different procedural patterns:

Thank you very much, for your answer. I added some details on my question above. How can I define the exact position of the pattern?

From what you've commented above you have a specific model you want to apply this to -- have you UV unwrapped it?  Search on "UV unwrapping" "Blender" if you don't know what that is.  Also, it's sometimes a good idea to post your blend file, or a truncated version of it that has the problem.  The Blender StackExchange has its own service to share blend files:  https://blend-exchange.com/help

somehow I managed to do the displacement with the UV Editor. Please see updated question above for the picture. At the moment it looks quite ok. But can you tell me how to increase the displacement (the holes should be deeper).

Thanks for the checkmark, but you shouldn't edit your question to essentially add a new question, it hampers the usefulness of our question/answer to others.  In your added graphic I see that the Displacement Node's Scale is 1.0, you might want to increase that.  But if you need actual holes you could use your displacement map thru a Color Ramp into the Fac input of a Mix Shader node for a Transparent BSDF and your Principled BSDF:  https://blender.stackexchange.com/questions/90392/how-do-i-get-transparency-to-work-with-the-principled-bsdf-shader

In my above comment my Scale recommendation is wrong -- details in my answer to your next question here:  https://blender.stackexchange.com/questions/253553/how-to-combine-displacement-and-material/253558#253558


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How do I link/snap vertices or edges of two seperate objects with Shape Keys?
So what I need to do is join the verticles along the edge of each body part (neck and torso) so that they stay together when I manipulate the vertices with Shape Keys (which I've already done, so ideally I would link them without losing the SKs).
I've tried making the head a child of the body but I've probably done it wrong as it has no effect that I can see.
Edit: In short, I'm trying to fix gaps between body parts that occur when using sculpt to create shape keys. Ideally I'd fix it systemically but if that's not possible then a quick way to fix each shape key would be perfect!
Many thanks for the help!

It seems complicated, why don't you join the meshes into one object, and can't you work with less polygons?

Well I wanna keep them seperate because they are being exported seperately (for a modular character), but if the only way is to merge them and then seperate them again for export then I guess that's what I'll have to do. Thanks

you can go edit mode with both objects -and shapekeys- selected and you should be able to edit to snap together both of their their meshes, drag select vertices or use proportional editing, pick two vertices and scale to zero, etc... also you could select the outer ring and propagate the basis shapekey... just some ideas


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How to read a pixel from an image texture with Python
My Python script needs to read RGBA values from a specific pixel of a texture bitmap.
How can I do this in Blender?

import bpy

D = bpy.data

image_file = 'Image.png' # this refers to an image file loaded into Blender

img = D.images[image_file]

# we need to know the image dimensions
width = img.size[0]
height = img.size[1]

print ( "Image size: ", width, " x ", height )

# define location of the target pixel we want to read
target = [150, 33] # X, Y
print ("Target vector: ", target)

# target.Y * image width + target.X * 4 (as the table Pixels contains separate RGBA values)
index = ( target[1] * width + target[0] ) * 4
print ("Field index: ", index)

# aggregate the read pixel values into a nice array
pixel = [
    img.pixels[index], # RED
    img.pixels[index + 1], # GREEN
    img.pixels[index + 2], # BLUE
    img.pixels[index + 3] # ALPHA
]

# print the values for debug
print ("R: ", pixel[0])
print ("G: ", pixel[1])
print ("B: ", pixel[2])
print ("A: ", pixel[3])

I wrote this based on articles from this blog:
http://blenderscripting.blogspot.com/2012/08/adjusting-image-pixels-internally-in.html

I found that working on a local copy of the pixels results in a huge performance improvement, if you want to write many pixels. Just use local_pixels = list(img.pixels[:]) and local_pixels[index]=red_value and img.pixels = local_pixels[:]

For some reason, this doesn't work for me... It doesn't crash, but all pixel values are 0.0...

@ThomasHarris may be it's because of the blender version? This question is from 3 years ago and Blender python API changed a lot since then.

works for me, indeed local data goes way faster


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Baking should happen to image with image buffer
I'm trying to bake Normals from Multires on a model, but lately I've only been getting the error "Baking should happen to image with image buffer". I can bake multires on a new blender file, but if I import my FBX and try to bake normals I get the above error so I think there is something up with the model. The model has multiple UVs and Shape Keys but it was working at one point when that was also the case.
Any help would be awesome, thanks!
Edit: the problem still occurs even if I clear all UVs and SKs and regenerate a new UV.

Try saving the image in blender or to a file

Thanks for the quick reply, unfortunately that doesn't worth either, I've tried not saving, packing in blender and external files and they all do the same thing. The same thing happens even in a fresh blender file (when I export the original FBX)

Do you use UDIMs? https://blenderartists.org/t/baking-image-buffer/1294362

Nope, unfortunately not

Such kind of error happens in three cases :

texture (you trying to bake on) was moved to another folder

texture was deleted

".blend" file itself was moved (while texture was NOT)

__
So, basically, that error means: "Path to the texture is not valid anymore"
To fix this:
just press the "folder icon" on your texture node and set a new path to the texture.
So simple.


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Problem with Array Modifier in tutorial "How to Create Robotic Arms in Blender"

I've been trying to follow the workflow of the tutorial as closely as possible, but I got stuck at the "Modeling and rigging the claw" stage. Originally I needed to generate three claws that were exactly the same shape.
When I applied object offset to claw duplicator(Triangle one), somehow all three ended up being different sizes. The three should have been exactly the same size and shape. Since the same question was posted I think this needs to be addressed.

Pls provide blend file

There's a comment below the video by 'ishmael mercado' saying that you should apply all transforms to the claw duplicator at around 9:45 in the tutorial rather than clearing the location. That's the next option below 'Clear' on the menu and apparently solves the problem you're having..

Resolved. Thanks to you.


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.Step file problem
I have an issue with .STEP file.
Blender doesn't show my image texture on a .STEP file imported from Solidworks.
I am working with shader editor and shading window and the wood material is missed
The strange thing: a mesh directly created into blender shows the material perfectly, while the object imported as .step file doesn't read any texture.
Anyone can help me?

https://blender.stackexchange.com/questions/38651/what-does-unwrapping-a-model-do-and-why-is-it-important/38653#38653

Thank you so much!!


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Bug? Can't Boolean-Difference an object after using Spin?
Forgive me, I'm a Blender Noob, but I can't for the life of me figure out what I'm doing wrong.  Can anyone please either reproduce this bug, or explain what I'm doing wrong?

Start with a short cube wide enough x/y to cut an array of holes
Create a thin, tall (>cube height) cylinder that extends above & below cube
Move that cylinder from 0,0--away from the center and toward the edge of the cube
You should now have a thin cylinder sitting off-center within a cube
In Edit mode, use the Spin tool to "extrude" multiple copies of the cylinder 360° around z-axis with a count of 4 (or any #)
You now have 4 tall cylinders equally spaced within the cube
Using Boolean tool or Modifier on the cube (both result in same for me), subtract/Difference the cylinders from the cube.

I don't get any result whatsoever. Both objects remain independent, unaffected by the operation.  HOWEVER, if you switch to Union, they join just fine and become a single object.  Also, if you switch the operands and subtract the cube from the cylinders, you get a proper gap in your cylinders.  Why can't I subtract the cylinders from the cube?
Thanks in advance!
Removing cylinders from cube with Difference to make holes in the cube fails:

Adding cylinders to cube with Join correctly creates new merged object:

Removing cube from cylinders to create a gap in cylinders works:

I'm having trouble following your steps.  Maybe you could link a file showing the boolean failure?

@Nathan, I added pics.  Also this is really simple to reproduce, but I wasn't clear in step 5 that "Spin 360" means use the Spin tool to "extrude" multiple copies of it in a circular pattern, not simply rotate the cylinder.  Hope that helps!

I figured it out. Maybe not a bug, but understandable odd behavior in Blender.
1st part of solution is the checkbox "Use Duplicates." This makes duplicate meshes that properly make holes with Boolean Difference.  The 2nd part of solution is fixing the degrees rotation in the Spin 360°.  The 360 means my original cylinder starting at 0° gets confused/clobbered with the last of 4 copies at the 360° position, causing the Boolean to not function properly.  The fix is to only Spin 3 Duplicates over 270°. Now works perfectly as expected.

Success!


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Illustrator type shader?
How do I make this shader (illustrator type artstyle but 3D)

HOW DO I IMPROVE THE SHADOW? MAKE IT COMPLETELY SMOOTH AND CRISP LIKE AN ILLUSTRATION?

Hello and welcome. Please don't write in all caps in the title or body of any posts, it is the written equivalent of shouting, is harder to read and may be considered rude. Please use the [edit] button below the post to change you text into regular case.

Just use an emission shader / don't use a shader node:

To still get shadows, use a shader and pass it to "Shader to RGB" node (works only in Eevee). You may want to research "NPR rendering".

I added an image , i want to improve the shadows . how do i do it/?

@NewBlenderer define "improve".

my shadows are jagged. how can i make them like that in the example picture

@NewBlenderer try decreasing the radius of the point light to 0, and in render settings, disable soft shadows and increase their resolution…

Hi , the point light works as desired, but is it possible to have unlimited range like the SUN light?? The Pointlight has limited light spread.

@NewBlenderer I know I had problems with Sun light as well, there are some shadow improvements coming in "Eevee Next"…

Ok Thank you for the info. Exciting to see what's new in Eevee! :)


text:
Create Cylinder to 6 Sided to Cylinder Transition Topolgy
I'm trying to create a mesh that smoothly transitions from a cylinder to a hexagonal body.
I have create the mesh as per attached pictures however when I apply the 'Subdivision' Modifier it doesn't look right because the transitions are very sharp.
Any advise about how to improve the mesh?

Thanks!

You can try another topology:

First bevel your hexagonal shape:

Extrude, then right click > LoopTools > Circle:

Rearrange the topology a bit:

This helps, many thanks!