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How to make the texture not follow the mesh deformations (Bouncing and stretching ball)
I want a bone to control the rotation of a ball. But the stretch bone also rotates it, since the texture follows the mesh and stretches and rotates with it. So the texture needs ignore the mesh rotate using the info of the bone only. Currently the texture is using UVs, which I know is stupid so what's the best way to do this?
Here's a screencapture: https://drive.google.com/file/d/1dZnNn_P0kz35zvRJni72l8knh07ri2wx/view?usp=sharing

hello, it's a little confusing to me, could you please show what the ball and its texture are supposed to do with 2 or 3 drawings/pictures?

Have you tried with a lattice?

Yes I tried lattice but it didn't work because rotating it produced some weird twists and stuff.

your rigging seems complicated, I'm a bit surprised that you need such a complicated rig, what was the problem with lattice, what kind of weird twsit?

Was the lattice add after the armature?

Once you rotated it beyond a point the lattice started to deform the ball into a cube. The lattice is also cube shaped.

@lemon no, it was before, I was trying to get the armature control the lattice.

@Necryl, why before? the lattice should use the transformed vertices, don't you think?

the lattice would  still deform the ball into a cube without the armature.

@lemon, that's true but the rig would still rotate it while trying to stretch. Wait guys I have an idea. I'll tell you if it works

you could create a lattice, hook its 8 vertices to 8 bones, parent both the lattice and armature to the ball, move the ball and deform with the bones?

I got it working! So basically I found out that once we have a armature controlling the lattice. When rotate that armature in object mode, we don't get any twisting, and the texture doesn't follow the mesh either! So I just made a second armature to rotate the first one and to have the stretch and squash controls. Thank you, your answers gave me the idea. I'll post a link soon in case you wanna see it yourself.

https://blend-exchange.giantcowfilms.com/b/en23nWJl/ This is it. After trying to do this for days, it kinda feels like magic that it actually works.

@Necryl, great! You should write your own answer.

So I got the solution. I used lattice to deform the mesh. However if you rotate the lattice in edit mode, the texture will follow the mesh. But if you rotate the lattice in object mode, the texture doesn't follow the mesh. If you rig some bones to deform the lattice, and have them rotate the lattice as well, the texture will follow the mesh again because the bones seem to rotate lattice points, not the lattice object. However if you rotate this armature in object mode, it will rotate the lattice as object as well. What I did was, I used a second armature to rotate the first and consequently the lattice. I also hooked up the lattice deformation bones in the first armature to copy the location of some bones in the second. This meant I can deform lattice points as well as rotate it as a object in one armature/rig.
I am not the best at explaining so I'll link the files here if you wanna understand how to do this.
Here's the first file that I was struggling with. In this file the texture follows the mesh and is not independent: https://blend-exchange.giantcowfilms.com/b/lgJWddwp/
Here's is the file with the problem fixed. In this file the texture doesn't follow the mesh and can be controlled independently from the mesh deformation: https://blend-exchange.giantcowfilms.com/b/en23nWJl/


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Why is my limb flipping when trying at constain to armature?
edit:
I don't know what exactly I did but I fixed it... I renamed my bones as for some reason all my bones had "L" on the end of them, I must have forgot to change the names after mirroring, maybe this will work for you if you have this problem too.
I'm trying to figure out why my character's upper leg rotates by 180 when constraining to my armature's bone. even if the weight is as small as 0.0001 the same thing happens. I've tried applying transforms and clearing but nothing seems to work, I'm really stumped. Sorry if this isn't enough information I'm not sure what else to write. Thanks.

Comments are not for extended discussion; this conversation has been moved to chat.

To sum it up :

Join all the meshes within one object
Recalculate the normals in Edit mode
Apply the scale of both the armature and the mesh (once done read here to correct the armature)
Select the knees of the armature and in Edit mode bend them a bit forward
Enable the Deform option for each bone that is supposed to act on the mesh (not the IK targets or pole target, not the root bone)
Select the object, shift select the armature, parent With Empty Groups, then switch the object to Edit mode, select one mesh after the other, and in the Properties panel > Object Data > Vertex Groups list, select the group it is supposed to be part of and click Assign
Correct the IK constraint Pole Angle value if necessary

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How to make a glowing crystal texture in Cycles?

This is my node setup and the type of output I desire. However, this works well if the shape used is a sphere. I want to apply this same effect on an elongated sphere (some close to the shape of a rice grain) evenly. How do I go about it without increasing the geometry of the scene?

Can you post a picture of what happens when you try it with an elongated sphere? I'm not sure I understand exactly what the problem is.

Adjust the X,Y and Z scale values of the Vector Transform Node accordingly so the gradient is correspondingly elongated too.

Change the mapping type to texture and scale one axis to match the elongation.

You can achieve a similar effect using the OSL shader developed for this (Distance from the surface as an input node for use with volumetric materials) answer.
Here is the material node set up :

Note that I've swapped the IOR for the Glass shader compared to your answer. I believe you must have flipped your normals to get the effect in your example image - adjusting the IOR produces the same effect for refraction.
This produces the following result :

Adjust the Multiply node and the Emission strength to adjust the glow.
EDIT : You can adjust the prominence of the glass by either reducing the IOR further (although depending on the look you're looking for this might be undesirable - the refraction might look 'odd' since low IORs don't exist in the real world) or by adjusting where the 'glow' starts - either by adjusting the Color Ramp to increase the 'black' region or by adding a Subtract node to shift the start of the glowing region away from the boundary. I've updated the material to include the Subtract node (and have removed the unnecessary Mix shader).
Here's an example with decreased IOR and increased gap between the glass and the glow.

ok, that solved it, but 1) what does the mix shader node do? 2) is there any way to have the glass layer look more obvious/noticeable from a distance?

Also, what does that "iterations" counter do in the OSL node?

Apologies for the Mix shader - that shouldn't have been there and was left over from mixing in other nodes to try and get the desired effect. I've updated the material to remove it and also added a Subtract node to allow you to separate the glow further from the glass.

The OSL node projects out multiple rays from within the volume to 'probe out' the surrounding mesh. The more rays it sends out, the more accurate the result will be, but the longer it will take to render. The Iterations controls how many of these 'probe rays' it sends out from each point in the volume.

@Rich Sedman, do you have channel in Youtube?

Sorry @RitaGeraghty I don’t have a youtube channel.

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How to make a sky-to-ground view shader?
So, I have a scene with a cube which I have modified into a group of clouds and a plane which I intend to be the ground. The camera is placed such that I can see the ground through the scattered clouds.
Like so:

However, I'm not able to create the ground shader. I need it to look as realistic as possible.

Maybe use a photo?

@seaturtle I couldn't an HD image of it. If you can find any send a link my way.

Just google “earth from a plane” or similar : https://goo.gl/images/Uh6vj7

@RichSedman I tried using various HD images, the result wasn't satisfactory...I suppose images just don't cut it

Make the ground surface and with the cloud addon make cloud from the top view set the camera

@atek yes, I know.. the question is "How?" I already made the clouds, by the way

I would recommend the Space VFX tutorial, you can also find some free procedural planet tutorials like this

click to enlarge
By feeding a wave texture into a noise texture,combined with true displacement, you can create a good starting point for a procedural terrain. The color ramp determines the shading, and the RGB to BW node creates a grayscale mask from the color ramp for the parts that should be water.
Here is the node setup, this is based around the planet plane material from the material library vx add-on which is now included in blender as of version 2.79:

click to enlarge
The contents of the displacement node group:

click to enlarge
The file to play with:

This works beautifully, but I have another question, is it possible to control the colors based on height? I have used the ANT landscape addon to create mountains, and I want the green part only on the "flat" surfaces. I tried to do this myself but was unsuccessful, some help would be greatly appreciated.

Ok, after a lot of searching, the best search phrase is "NASA aerial view", you get many HD images without watermarks on them.
I used an image to do it this time, although, I am still interested in learning how to make a procedural shader for this.

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Make particles clump together and flow in a specific direction
I am creating a cel shaded fire using a particle system in which I want the particles to clump together and flow in a specific direction. Is it possible to make it 'look' and behave more fire-like?

This is campfire example.
To achieve this effect add two force fields.
First one: Shift+A > Force Field > Turbulence
Then change Noise to 5.

Second one: Shift+A > Force Field > Vortex
Change Noise to 2 and Strenght to 0.1.

Blend file:

Final toughts:
I don't know your full setup so some values may vary. You can try change position of force fields and strength/noise values.
Edit:
Based on provided blend file I've change all Force Fields to Force with negative strenght and noise. Also I've zeroed Velocity > Emitter Oject > X and Random.
This is how it looks with Motion Blur.

Updated blend file:

Check my blend file first and play animation to see if this is what you want. GIF does not show it accuratly.

ok, I've added my set-up's file, can you give it a look? but to simplify my query, I want the particles to move and behave as fire in the X-direction.

@Tejas check my edit. I think it's pretty close to fire effect. Tell me if it's ok. You can alway add back one Turbulence force to it.

@Tejas I've rendered it with Motion Blur to check behavior and it looks pretty neat. Check edit.

thanks mate, i'll check it now... sorry that i couldn't reply earlier :)

This is superb, man... thanks for all the help :)


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Fog glow and motion blur in cel shading
I'm designing a cel shaded phoenix in Cycles. I have used particles as flames as opposed to using the smoke simulator. Now, i want to add motion blur and fog glow to those particles to make them look more fire-like. Any suggestions? Thanks in advance.

This is my basic set up:

hello again :) are you satisfied with the motion blur effect from my previous answer? Or do you need something else?

@LukeD hey, yeah, you used the 'Motion Blur' from the 'Render' Tab, I want the particles to have a trailing effect. Also, notice because of the 'Motion Blur' some of the free style outlines are empty-ish. (Sorry, if my project is being too demanding) XD

I don't think I get it right... Could you explain those outlines based on screenshot?

@LukeD https://i.sstatic.net/MVf9r.jpg look at the particles outside the red region, they are kinda empty.

ok, now I see it. It seems like motion blur affects only inside of the cubes and cell shading is added after motion. Possible solution could be to make layer with moving paricles without Cell Shading to keep motion blur, and another one with Cell Shading but withouth movement. Il'l look into this later if you can't figure it out till then.

@LukeD oh, ok.. and then merge the layers... got it.. I'll try that out and another idea I have. Will update the result.Let you know of the outcome. Thanks again, mate.

You will have to do the motion blur in the compositor. Just check the Vector pass and plug it into a vector blur node and you're done:

If you want fog glow, mask the glowing materials by setting the material ID on the materials that should be glowing. Add a glare filter and add it to the rest of the image. The filter resolution is set to low because it increases the effect's size (I really don't like how you control the size of fog glow in Blender). Consider using a blur node as an alternative if you're not happy with the results.

If you have a lot of render time, also consider using the not-faking-anything method:

Make the cube's outline real instead of using freestyle. This can be achieved through texturing, vector paint and perhaps clever shading.
Add a Volume Scatter node as the world's background. Volume scattering (and absorbtion) are basically physical fog.
Adapt your lighting (increase the emission shader). Volumetrics really suck lighting
Enable real, Cycles-rendered motion blur.

With this, your render time will explode. But it will look nice :)

that's one down and for that you have my thanks , any luck with the fog glow, though?

I'm working on it.

@Tejas That is what you want? I've had another thing in mind. Blurred trails and sharp cubes.

@LukeD hmm..ok, I listening... fire it at me

@Tejas First of all if you want fog glow based on piegames method, after Vector Blur node add Filter > Glare set it to Fog Glow and Treshold to 0.1. I'm fiddling with my method now.

And by the way, never use an uneven number of samples. It always gives you way more noise than the even ones.

@LukeD thanks both for your help in this my only regret here that i can't credit you both equally on this site :)

authors: Виктор Сидоров


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How to randomize particle effects along a curve guide?
I have set a curve guide as the Effector Group of my particle flow. Now, the particles move along a linear path, I want some of them to take a more random path -- like some of them follow the path but then slowly deviate away from it -- so that it seems less obvious. Is there any way I can do that?
This is my setup:

try reducing the influence of the curve guide and increasing the Brownian motion (random movement) of the particles.

@3pointedit i'll try that

@3pointedit hey, thanks that worked, but is there any way to restrict the brownian motion to the Z-axis?

Don't think so, as its a genuinely random motion. Perhaps instead you could move them through a field effect like turbulence or texture?

@3pointedit ok, i had it sorted out, not the according to the question I asked, but thanks anyways

IF you had an alternate solution why not post that as another question/answer so that others can learn ;-) You're allowed to answer your won questions here.

@3pointedit good idea

As far as i experimented with my project, I couldn't find a definite solution. However,I was able to bypass the problem. I aligned the normals of the emitter along one of the axis, then with required level Brownian Motion set, I increased the Normal velocity of the particle system. Later I baked the Particle System, however this step was of my preference.
Similar results can also be achieved by setting a Particle System with the necessary -- Brownian Motion and Normal Velocity -- settings along with a Force Field of negative strength. Note that both the Particle System and Force Field have to exist on the same Layer. Also, a Force Field affects all particle systems present on the layer. Therefore, while using multiple particle systems place each of them on a different Layer if you don't want the Force Field affect them too.


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'Modeling' a sparkling flare?

I want to recreate the above images for an animation. How do I go about it? I tried using particle systems and smoke simulators but to no avail.
Also, I want to model a sparkler, but more akin to a sparkling point or sphere that emits in all directions.

Check this one: https://www.youtube.com/watch?v=QCMyvcc3ZaU

@LukeD yes, I'm familiar with that tutorial, but i ended up making my 'model' into amalgam of satanic lines, I tried every possible combination for the particle system which  I could think of

Particle system is fairly simple to set (high normal emiter and 0 gravity) but I'm struggling with those sparks 'outside'. They are changing directions realy quick. I've managed to set particle system inside ico sphere as collision but when I try to animate this ico sphere to get random bounces particles doesn't respond to it.

Check this out: http://imgur.com/a/R9zHU

@LukeD that's perfect, just need the center to be a sphere and a bit bigger

Final (almost) result

I will not go trough all steps in detail as they aren't part of the question (animation, modeling this sparkling stick and such).
Particle system
Create IcoSphere and scale it to be a bit wider then stick and add to it Particle System.
Create another one and move it to another layer - you will use it as particle object.

Most important settings are:

Lifetime, short lifetime does not allow particles to bounce and long one will get all of them messy.
Emitter Geometry > Normal. This will give our particles initial speed.

The rest of them are just some little tweaks.
Do not forget to set Gravity 0 in Field Weights tab.
Collision system
This is the tricky devil.

Create IcoSphere (Subdivisions 2) go to Edit Mode and Wireframe view (Z).
Select all - A and hit CTRL+E then Edge Split.
Select all again and set Pivot Center to Individual Origins then scale it down little bit. You should get something like this:

Now you can duplicate it and make them smaller, bigger, with any rotation - as you like. Remember to set Pivot Center back again to Median Point.
Final step, still in Edit Mode add another IcoSphere and make it the biggest one. This will be boundry for our collision system.

My final setup looks like this:

Creating collision system is the worst part, everything depends on it,
  so you must try to make it right. If you want sparkles to be bigger,
  make whole thing bigger, if you want them to be more round - scale
  down less after edge split, to have smaller holes between faces.

Go back to Object Mode and in Physics tab add Collision. Set Particles > Permeability to 0.3. This will allow particles to "break" collision system. You can set it to 0, then nothing (yup, almost) go trough.
Hide this object in Outliner and set it to not renderable. Eye and camera Icon.
Materials
We will need only two materials, for sparks (particles) and particle emitter. Select IcoSphere you've moved to another layer and add this node setup:

Select IcoSphere which is emitter for particles and add to it Transparent node with pure white color.
Motion Blur
Go to Render tab, check Motion Blur and set it to 1.10.
And that's it.
Here is .blend file with all animations:

So, there's one icosphere that's an emitter, another icosphere that's the particle and a third one that's a collision object. and the third icosphere has an edge split icosphere inside a regular icosphere, correct? So, is the emitter smaller than the third icoshphere?

Yes, emitter should be as big as the stick (little wider) and in third IcoSphere you can duplicate as much as you like them. In my blend file there are 4 if i recall it correctly.

ok, consider if i have to use this thing for a laser or welding animation, how would i add a trailing effect to it? like you know, after a laser has burn over an area the burn part is red hot before cooling off

Dynamic Paint. You can even make cut hole with it. There is plenty question and answers about it around here.


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I am trying to model a pencil. Can you help me in modeling this pencil?
I am trying to model this pencil

Have you tried reconstructing the geometry from from the answer to your previous question ? https://blender.stackexchange.com/a/265462/86891

Create a 8 vertex circle, subdivide twice:

Extrude up, move up the inner vertices:

Extrude up again, then keep the top edge selected and right click > LoopTools > Circle:

Bevel these edges:

Extrude and scale down the top to create the tip, create another circle at the base of the slope to make it rounder:

Give it a Subdivision Surface modifier:

As for creating the effect where towards the end and on the cone section there are "half circles" at the end of the "hexagonal cylinder" part, what you could do is have a high definition circle cylinder, with at least 32 vertices, but the more the better, and then use cubes with the boolean modifier to "Scrape" off the wood into the final shape, like this


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How to create a good topology from SVG for 2D animation?
I have only the outline drawn as a vector in svg file. Click here to view. I import it to blender. It becomes a path. I convert it to a mesh.
Now, I would like to subdivide it and have it in a good topology (square faces or quads) so that I can animate it.
I tried many things but they  don't work such as: Right Click and subdivide > Adding subdiv surface modifier....etc.
How can I do it, please?
Why do I want to do this? Because I have a colorful png image and I want to simply animate it with bones. Just like what happens in After Effects.

For such a thing I would filled the outline by delaunay triangulation ... I just can't remind me what addon he this as a side function that I work with few weeks ago ...

@vklidu Come on! Try to remember man. Go to the files of your project and you may be able to find it.

There is a remesh tool built in Blender but you're better off using specific softwares for such task. For example autoremesher or instant meshes (which are free to use) or paid alternatives for a better experience.

@Gorgious I downloaded them and I'll try them later and get back to you. Thanks for your comment.

What is good topology for 2D anim depends on how this animation should looks like. There is many technique and styles so for example you can try
CutOut animation
model cut into several parts driven manually or armature. For this kind there is awesome addon Cut-Out Animation Tools, that make it very easy to work with (includes script to generate parts from Photoshop or Inkscape layers in proper position and ready to import to blender with click to generate armature).
Grease Pencil
Very powerful anim tool set with many options of creation and animation, frame by frame, using sculpt mode , or armature as well ... example one of many
Delaunay Triangulation
For some kind of animation could be helpful to use triangulated topology. There was a script for Blender 2.49 that I can't even find. But similar feature is a part of great BlenderGIS addon, but it doesn't generate point cloud for triangulation (as the old one) it just connects the points. So to get Delaunay work you have to generate a point cloud first.
I'm sure there has to be a simple script that can do this in a one click, but in meantime here is one solution ...

Download, install, enable BlenderGIS addon

Select SVG curve convert to mesh like Ctrl+A Visual Geometry to Mesh

In Geometry Node editor add New, add Point Distribution node type Poisson Disk and merge original mesh with points by Join Geometry node as shown bellow

Apply Geometry Node modifier under Properties editor > Modifiers
Search for GIS Delaunay (or go to 3D view editor top row menu > GIS > Mesh > Delaunay)

Notes:

Poison Disk can be generated also by addon Point Cloud Visualizer
Delaunay can be generated also by Archipack addon under Terrain
or there was a Point Cloud Skinner addon, but v0.18 works only for blender 2.83 not 2.9x
I saw some technique of delaunay triangulation based on Voronoi pattern (out of blender)


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Varying a size of instances
I have icospheres instanced on a sphere in the first screenshot and I want the icospheres to vary in size like the spheres in the second screenshot. How do I do that?

Random Value node into Scale (probably Map Range node would be needed too.

There are so many answers here describing how you can use the Random Value node together with Instance on Points, ...I am still looking for the appropriate duplicate. But as @vklidu said correctly: Random Value will help you here.

Here is an easy way. You could put a Scales instances in front of the Instances on point and connect a Random Value + Vector Math (in multiply) and add those to the scale

Here is an example: https://vimeo.com/653258060 AT minute 1:47

Probably enough too ... https://imgur.com/Sb5jyh1 :)

@vklidu yeah, but it was in case the OP needed the original scale for something else

If your answer should stand on its own and not rely on an external tutorial (as it would be preferred on this site), then your setup does not help at all. It's not adding anything to the original scale, it replaces it. And since the Vector Math node just multiplies all random values with 0, resulting in setting all scales to 0 and thus making all instances disappear (as it does in the tutorial as well by the way, only after changing the multiplier to values different from 0 it starts to work), this answer is no solution.

@GordonBrinkmann the video is just an example, you could delete the link and the image is still showing the way, if the answer does not work for you, you could downvote it without any problem.

Explain to me how multiplying everything by 0 gets you random sized spheres. And that's all your answer shows.

@GordonBrinkmann I understood your point, not everyone will think logically and change the value numbers of a node in order to see a result and as I said, you are very welcome to down vote the answer and report it, there is no problem


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Can’t position Gradient Texture on Object (eyeball) properly
Every time I try to center the light in the middle of the eye like in the tutorial, it doesn't work and ends up centering around where I put the mark seam.
It's supposed to look like this:

But turns out like this:

If anyone knows what's wrong and can help me I'd really appreciate it. Thanks, tutorial's linked below if that helps.
www.youtube.com/watch?v=E0JyyWeptSA
And here's my blend file:

Okay. I'll remember that for the future. Thanks.

Your issue is position of UV map.
Tutorial (and you) are using UV texture coordinates, but your UV map is not placed in center of "UV Editor". Since you move the front part of eye in a center it matches.

BTW instead of UV I would rather use Texture Coordinates
type Generated (Loc -0.5 / -0.5 / -1)

or easier type Object (Loc 0 / 0 / -1)

This worked, thanks so much for the help and tips. :)

If answer helped, consider to mark answer as correct by clicking on check mark (under vote arrow) to let know others (with similar issue) this was solved for you (visible from Q list too). Thanks


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How to model this irregular shape
I'm looking for the optimal way to model the back part of this camera (just the back with the viewfinder) while having a good topology. The general shape is easy, but I can't get the viewfinder and the way it merges with the rest of the shape right. I've tried from sculpting to drawing it with a beizer to using a lattice, but it never looks right or the mesh ends all messed up. What would be the best way to do it?

My best attempt:

I got there using a subdivision modifier and adding support loops and creases. Then I joined it with the viewfinder (a separate mesh) using a boolean modifier.
But the mesh is a mess. Is it a good approach? Is it worth fixing the mesh?

The bottom-line is that no matter what I try, I can't get this curves right:

I am not an Expert about blender, but i can help you.
Start off with a cube.
Go in edit mode.
Subdivide the cube by a small value (4).
Grab the edge you want to pull inwards ONLY ON ONE SIDE!
Move the selected edge inwards. (G Key).
Exit edit mode.
Apply a mirrors modifier (use the correct axis).
Now you should have the curve on both sides.
Grab the intact face on the back.
Extrude It where you want that  "long rectangle" to be.(E Key).
And grab the tip face of the long rectangle.
Inset that face a bit.(I Key)
Extrude the insetted face inwards.
Grab The Bottom of your creation.
Extrude It Down.(E Key).
Enable Shade Smooth.
P.S.
If the model looks weird After Shade Smooth, go ahead and enable Auto Smooth Normals!
I'm Sorry this Is a bit of a weird and probably not correct answer, but i've fine my best.
Hope you Will understand It.

Thank you very much. Doing it like that I got to something similar, I will add pictures to the OP. The problem is I can't get the curves on the sides and below the viewfinder right

Try using a Bevel modifier. If that does not produce the exact result you wanted, select manually the edges while in edit mode and apply the bevel yourself.
also try going in the mesh tab and enabling auto smooth normals, and i dont reccommend using a subdivision surface, but instead using Shade Smooth.


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Grease Pencil Render Error
When I try to either switch a grease pencil's material's alpha from 0 to 100 (ending in black) or change the material's fill color from black to white, a small number of strokes in the grease pencil object disappear during the render and/or don't show on the gray scale during a render and/or don't match the rest of the strokes in the object. It seems to be happening between frames.

Any help is appreciated.

Yes, they are all on the same layer and all have the same material.

I found a very, very crude work around. It appears to be happening to the last number of strokes. If I add additional strokes into the object, it appears to cause issues with those, by moving those outside of the rendering, the actual strokes in question don't appear to have issue.

Interesting. I am also using 2.81. Would imply to me probably a hardware or driver issue? To be clear, you didn't change any of the render options? Thanks.


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Baking the normal map from high poly mesh ends up weird. I have no more ideas how does this work
Well I just heard that for creating game asset I should learn how to bake normal map on the low poly model from it's high detail version. I tried to follow tutorials but no matter what my results end up poorly, like this:

Low poly mesh is uv-unwrapped, both have smooth shading too and I'm in cycles render. Now I've tried everything. Incerasing ray distance does nothing and creates seams, using cage mesh removes seams but still details look bad or won't even exist. Changing margin size seems to do nothing at all.
So my normal maps seem to work only, with smoothered edges, adding holes or some shapes sticking out of the mesh, do nothing at all or just look poor. I have no idea what's going on so either I'm missing something or Blender hates me and won't allow to bake a normal map.
Edit: Additional details

Left mesh is low poly with normal map, right one is high poly, and that's the normal map I got. By "it looks poor" I mean, that the top part, doesn't even show on the normal map and these small faces around the mesh that are going slightly inside, are missing top and bottom part from the high poly version (right mesh)

in what way does it look poor? Are these 2 objects the low-poly ones?

Hello :). Please add your normal map result and bake settings. It works just fine for me.

Is the problem that it looks too extruded? Have you tried decreasing the normal map strength when reconnecting?

@JachymMichal done.


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Python: Access preset of curve bevel custom profile
Is there a way to use Python in order to select one of the presets for profiles of curve bevels?


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How to simulate reflection of people in a 4 meter parabolic mirror to show that they won't appear upside down?
Answers to the Space Exploration SE question Which Apollo “mystery” was said to be finally solved by a better rendering engine? demonstrate that sometimes a correct rendering is the best way to address a problem.
A question I've recently asked in Astronomy SE Why are these telescope mirror makers not upside down? (Daniel K. Inouye Solar Telescope) can probably be quickly, convincingly and definitively addressed with a quick mock-up in Blender.
While I've used it in the past it's mostly from the Python scripting size, I have never developed any aptitude mousing my way around even though it looks easy.
So I thought I'd pose this as a related but different question here, and if answers here can also be used as guidance to how one might produce an answer to that question, all the better!
I will then give it a try myself, but I'll be slow and if someone beats me to it there, great!
The mirror in question has a diameter of 4 meters. It is f/2 meaning the focal length is $f=8$ meters, and Wikipedia tells us that the height of the mirror as a function of radius should be:
$$h_p(r) = \frac{r^2}{4f} $$
This can also be fairly well approximated with a sphere of radius $2f$ or 16 meters which can be generated in Blender without an equation, but just for completeness:
$$h_s(r) = 2f - \sqrt{4f^2 - r^2}$$
It's an off-axis paraboloid, but not very much off-axis; just enough so that the secondary is not directly intercepting the sunlight illuminating the primary, in order to reduce diffraction effects.
Question: Based on perspective cues and relative sizes in the image (e.g. handrail in front has larger apparent size than people's heads in back): How would one go about simulating the reflection of these people in a 4 meter parabolic mirror to show that they won't appear upside down?

The linked question in Astronomy SE:

The new open access Solar Physics article The Daniel K. Inouye Solar Telescope – Observatory Overview is the first of several papers about the new state-of-the-art solar observatory. For more info see Phys.org's Solar telescope releases first image of a sunspot
Figure 4 of the paper is shown below. It is the 4 meter primary mirror viewed at an oblique angle with several people in clean room garb standing behind it.
We can see their reflections in the mirror as well. The geometry is similar to people standing on the opposite side of a reflecting pool.
What struck me is that this differs in an important way; the people are not upside down!

Why not exactly?
Would the people see the camera upside down then?

It looks like the photo was taken from fairly close to the mirror based on the strong perspective scaling from foreground to background objects.

(Figure 4) The 4-meter primary mirror (M1) after coating at the AMOS coating facility on Haleakalā.

I'm unsure about tagging; are there any tags specific to reproducing a few key geometrical elements of a scene for technical, scientific (or even forensic) purposes without having to be photorealistic? For example, the people's heads could be nicely shaded icosahedrons or a uv-mapped and work just as well.

The mock-up works with Cycles ray-tracing, straightforwardly.
One approach .. You can create the parabolic surface directly, as ShiftA > Mesh > Math Function > Z Math Surface. Perhaps it's easier to extract the profile from a ZX function, curving in only one direction:

.. and having deleted all except the vertices: X>=0, Y=0, spin it with a Screw modifier.

Give the disc a 100% metal, pure White, 0 Roughness, mirror-surface.
The right-way-up virtual image is visible only from certain camera angles.. (if you play, you can see the hall-of-mirrors slide from wrong-way-up to right-way-up).

Maybe, for perfection, you could calculate the ideal normal of the mirror as a function of object-space XY, and plug that into the shader, to get rid of any artefacts resulting from the linear interpolation between vertices.. but for a demo, that doesn't seem to be necessary.

Robin, consider to protect Suzanne. Please add face masks.

@lemon I checked, (of course) -- there's no record yet of any simian crossover.. but you're right, we should set an example.

Sweet! You can see this about to happen to the tallest ones (mentioned here) This looks so easy that I will fire up Blender this weekend and try it, but it won't look anywhere this nice. Please feel free to post an answer there as well, I think that it's more than competitive with the existing answer ;-)

@uhoh Your idea, you go first :) Mine: nothing special, an HDRI environment knocked back to about .25 strength, Sun-lamp for the heroes, a rim for the mirror made from a (modifier-applied) copy of it. I'm sure you can do better.

(For whatever reason) I will want to script the whole thing, (1, 2, 3, 4) but I understand "this is my chance" to break into using Blender the normal way. It will take time. maybe this weekend...

@uhoh .. it is a mathematical subject, that other things could spring from, and ... maybe we share a masochistic pleasure in doing stuff the hard way :D. Whether you take the hard way or not, I look forward to your product / hitches on the journey.

Okay, it looks like I'm locked in now to learning "against my will" :-)

Fascinating topic!


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how to join two Navigation mesh?
I have an existing navigation mesh and that works fine with steering actuator. Now there is a need to extend the current navigation mesh and join another navigation mesh of certain length.
Please have a look at the attached screenshot, in the first screenshot, as I have shown I tried using 'Object Join' but that just destroys my navigation mesh(2). The individual cells of the navigation mesh(2) merges to one big cell, which I dont want.
As shown in the second screenshot, as I have shown, if I could merge the extreme cells of both the navigation mesh then may be the cells of each navigation mesh are retained.
Please help me to achieve this. Thanks in advance !

I figured it out, After Joining the navigation meshes, clicking on the 'NavMesh Reset Index Values' button under the Physics button, retains all the properties of the newly formed Navigation mesh.

Please add that (with a bit more info) as an answer.

You need to select both of the meshes and select join from the lefthand Tools->Edit->join area.
Once you have done that then you click on the physics tab on the right and select NavMesh Reset Index Values.
if you find you need to join two nav mesh's you probably need to go through and select all your objects, hit CTRL + A and select location, rotation, and scale for all your objects, then rerun the nav mesh generator, it should fix your issues and you won't need to join meshs.


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Object wired instead of solid
In blender 2.8 my object that i try to render looks both in edit and object mode wired, and i can't use smoothen to aussure a plain looking surface.
All the other objects around it are behaving normal and were able to use the smoothen tool.
Does anyone know how i can undo the mistake i probably made and to make the smoothen option usable on the object again?

First shot: check the 'Viewport Display' panel in the object's properties.. is 'Display As' set to 'Wire Frame'?

No, i tried to change the value to rendered or solid but the object remains in this state. It doesn't change but the objects around it do.
They get solid rendered and wireframed when i change the display style

Just checking.. that is the object's own  display properties....


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Array object offset to make a trapezium like shape
i'm trying to make a set of diamonds 7 diamond wide and 21 diamond long, with a slight offset so that the line grows longer (but only length, not number of items) the more you go down the seven colums of 21 dimonds.
Any idea how i might do that ?
So far, i tried with a first array of 21 down Y, then a second array of 7, along X, which makes a nice rectangle...

but I can't seem to make the offset bigger and keep it symmetrical...
help ?

thanks for the correction

applied a scale I had made previously. Might do it for me, not sure yet...

Sorry for delay.. Do you want all the diamonds to be the same size?

Assuming you want all your diamonds the same size, a simple approach would be to use Vertex Instancing, one way or another.
More Destructive:

Create a plane, scaled in Edit Mode to your 1x3 dimensions
CtrlE > Edge menu > Subdivide the horizontal edges with 5 cuts, and the vertical edges with 19 cuts
In the plane's Object tab > Instancing panel, set instancing to Vertices..
.. and CtrlP parent your gem to the plane.

You should now have a gem at every vertex.

You can now give the plane a Simple Deform > Taper modifier, down its long axis.
You can X Delete > Only Faces the plane, leaving you with a non-rendering wireframe.

Less Destructive:

Instead of using a plane, Create a Single Vertex at the origin.
You may have to enable the shipped  Add Mesh: Extra Objects add-on, (or just borrow a vertex from another object)

Give it Constant-Offset Array modifier, in X, count 4, and another in Y, count 21

Give it a Mirror modifier across X, ensuring 'Merge' is checked.

The rest is as above, using Vertex Instancing, and a Taper modifier.

The second method leaves your arrays live, so you can change the count/spacing at a later stage, if you want to, but single verts can be a bit more fiddly to work with in the viewport.
If you needed your gems to get bigger towards the bottom, you could consider a particle-system emitted by vertex instead, and use a gradient texture to control their size.

cheers Robin, i also asked on the blender artist forum. They had a similar solution.
I ended up making multiple arrays with object offsets and a mirror modifier to make the shape, which was this:

https://pixeldrain.com/u/XZLzzP9q
https://blenderartists.org/t/array-object-offset-to-make-a-trapezium-like-shape/1277560?u=bondareingal_baboon

and as it turns out, the diamonds needed to get bigger the more you went down.

@titheringuelly_tarentulla I like your solution! It's non-destructive without the faff of particles. Good way to go.


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If bump maps override face normals for lighting calculations, why do flat shaded bump mapped models look different from smooth-shaded bump mapped?
I am confused in regards to this. From my understanding, a bump map sort of 'overrides' the normals provided by the mesh faces for lighting calculations.
I also know that in flat-shading, a pixel is shaded based on color calculated with the normal of its face only, while smooth-shading interpolates the normals calculated at each vertex per pixel and shades the pixel accordingly. As such, flat shaded faces have the same color throughout while smooth-shaded dont
A bump/normal map essentially shades the triangle per pixel just like smooth shading, but the normal used is taken from the map/texture as opposed to some  linearly interpolated vertex normal. So logically, since normal/bump maps do this overriding of the normals to be used for shading, one would expect that a smooth-shaded bump map model should look identical to a flat-shaded bump-mapped one
After all, in both a smooth and flat shaded bump mapped normal, the bump map overides the normal in both cases.
Yet here is what a smooth-shaded Bump mapped Suzzane looks like:

And this is what a flat-shaded bump mapped  Suzzane looks like:

The difference is very subtle but it is indeed there. What exactly causes them both to look different? Isnt a bump map overriding the mesh normals in each case?

Related: https://blender.stackexchange.com/q/220408/110840

@AllenSimpson I still don't get it. From everything I've read, Tangent Space is (U,V,N) where N is the underlying geometric normal of the shaded triangle. The normal encoded in the Tangent Space map replaces the interpolated vertex normal due to smooth shading. The change-of-basis is calculated once per triangle, not once per pixel, for economy? In that case, I would expect the interpolated normal to be chucked out as irrelevant, and the smooth shading of the mesh to have no effect.

..or is the tangent-space basis precalculated once-per-vertex, and then that is interpolated across the triangle? That would make sense, and smooth-shading would still enable/disable the interpolation of what is considered to be the N-component of the map, in world space. That would explain it.

@Robin that could be, I've never dove into the code

According to the manual

The Bump node generates a perturbed normal from a height texture,
for bump mapping. The height value will be sampled at the shading
point and two nearby points on the surface to determine the local
direction of the normal.

This makes sense if you think about it for a moment. The bump map cannot completely overwrite the original normal because the map image itself has no information about which way the normal is facing in 3 dimensions because it does not contain a 3d vector like a normal map does. It only contains height information, which Blender samples to get a direction vector which is combined with the original meshes normal vector to create the offset. That original mesh normal vector enters the Bump node via the unconnected Normal input, and is affected by shade smooth.
For example, if we sample the bump map and get a height of 20, then one unit* to the left we get a height of 25, and one unit up we get a height of 30, we can make three points: (0, 0, 20), (1, 0, 25),and (0, 1, 30) from which we can do a little linear algebra and come up with a direction vector like (-0.45, -0.89, 0.09) which is then combined the mesh normal to get the final vector. **

a = Vector( (0, 0, 20) )
b = Vector( (1, 0, 25) )
c = Vector( (0, 1, 30) )

n=(b-a).cross(c-a)
n.normalize()

To give an example, we take a default cube with a bevel modifier and setup a viewer (emission) material to show its normals:

It shouldn't be too surprising that the face pointing up is blue (RGB 0, 0, 1), the face pointing left is red (RGB 1, 0, 0) and the face pointing forward is green (RGB 0, 1, 0). Note the absolute vector node so we can see negative colors. We can also see magenta (RGB 0.5, 0, 0.5) and other colors on the bevels.
Now add in a checkerboard texture as a bump map:

And look the effect that has on the normals:

The areas where the checkerboard is solid white or solid black have the same normal values as the unbumped example. The only changes to the normals occur where there is a color transition. So in effect, the bump mapping node acts like a directed edge detector for its input image.
*unit is left a little vague here, a pixel on the UV map might seem ideal, but it really depends on how the object was unwrapped.
** disclaimer: I did not read Blenders code, this is based on general principles.

So it basically takes both a point/pixel from the texture and 2 points close to the point/pixel on the mesh we are shading to sort of get a local 'angle' since the bump map doesnt have a way of telling WHERE exactly it points, just the magnitude or height of how much it points?

I believe it's using 3 points from the texture to determine the angle, where closeness must come from the UV unwrapped geometry, so the texture points may not actually be nearby on the image if the mesh point lies near a UV seam.

Could you explain what you mean exactly again? If bump map values dont tell us direction, how does using 3 points from the bump map texture give us direction/angle?

I edited in a paragraph to the answer, does that help?

Regarding your edit, if we add that direction vector to the mesh normal, wont that give us a vector with a magnitude greater than 1? Shouldnt normal vectors have a magnitude = 1?
And what specfic linear algebra operation did we do to combine those 3 points to give us (-0.45,-0.89, 0.09) exactly?

Regarding your second edit, does this mean, we basically form a 'triangle' out of 3 pixels on the bump map, and find the normal of that 'triangle' and then 'mix' that with the actual mesh's pixel's normal to perturb it to find the new normal?

You have the right idea. I added a simple node setup to let you explore this concept a little more.

Sorry for my late reply. I had also tried researching this topic elsewhere and from what I saw there, it is mentioned that the reason we take a pixel above and another to the left of a pixel like you described (the formation of a 'triangle' on the bump map) is to measure these partial derivative things in each axis
I noticed you had also mentioned we only notice a 'bump' on the mesh picture only if there is a CHANGE in bump values, which lines up with the idea of derivatives. But how can I conflate the idea of derivatives with that of the bump map 'triangle'? I struggle at that.

Since the bitmap is not a continuous function we cannot take the derivative (or gradient) at a given point, the best we can do is a numerical estimation by seeing the change from the current pixel value to the one on the left we estimate ∂u, and by seeing the change from the current pixel to the one above we estimate ∂v. This gives us a simple estimate of the gradient [∂u, ∂v].

Since we basically have to measure the partial deriviatives by taking into account the pixel to the top and to the left we are sampling, does this mean if I sample, say, 700 pixels to apply on a mesh, I am essentially reading 2100 pixels in total? (Because I measure 3 pixels for every pixel on the bump map). Is this why we use normal maps? Because those we only read one pixel for every pixel rather than 3 here?

The math is pretty straightforward and simple. Video cards are great at this kind of thing. Normal maps are harder to create, but tend to be more powerful, especially when you want long tilted or curved panels or otherwise fake geometry. Bump maps are easier to create but work better at seams and surface imperfections.

How do bump and normal maps differ? If bump map values are converted to normals, and normal map values are simply read as normals, does this not mean the end product is the same? Why do they each excel at specific tasks? Why can't a normal map for instance perform surface imperfections?

Bump maps are much easier to create, a decent artist could create one in MS Paint. Normal maps are much harder, generally involving creating high resolution geometry and baking the map. Surface imperfections are fairly straight forward by plugging noise, Voronoi or other procedural texture into a bump node. Baking a normal map to represent, for example, the texturing of a sprayed ceiling, from high res geometry... not fun or perhaps even possible.

I see. So the issue with normal maps for surface imperfections is that attempting to bake a normal map to recreate tiny surface imperfections would be very hard, if I am assuming right?
And as one final last question, we take the partial derivative on each axis per pixel on a bump map to calculate the normal by theory. You  also described another method to find the normal by assuming the pixel to the left and pixel to up as vertices of a triangle, and finding the normal of that 'triangle' by crossproducting the edges. How is the latter method equivalent to finding derivatives?

To clarify my question further, both these methods give us the 'normal' from a bumpmap value. Therefore logically both these methods MUST be the same. But I struggle to understand exactly how crossproducting edges  is equivalent to taking partial derivatives. Are they two different methods that lead to the same result or are they the same ?


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Object not following path
I have set two particle systems to move along a path while emitting particles. However, I'm having two problems. Firstly, the particles are moving slower than the emitter object and therefore is creating a gap between them. Secondly, one of the particle system is not following the path accurately.
This is my set up:

As you will see, one of the particles systems is following the path consistently, while the other isn't.
PS : Crank up the particle count for both the particle systems to 10000 or higher to view an accurate representation.
UPDATE: PPS : How do I delay the start of the path animation for one of the objects?

Problem 1: Fixing particles
To fix this go to the particle system tab under Velocity and turn the Object option up to 1.00.
Problem 2: Path follow
To fix this, go to the start of the animation, select the path, go into Edit mode and, with all points selected, click Toggle Cyclic in the Tool Shelf. You should now see a gap in the path, which is the start and end. Determine which one is the start(the path lines are leading away from it) and select it. Press Shift + S and select Cursor to Selected. Click Toggle Cyclic and go back to object mode. Select the object to follow the path and press Shift + S again, this time choosing Selected to Cursor
Problem 3: Delay animation start
The only easy way to do this is to use a Follow Path constraint instead. It allows you to offset the animation. You could also just rotate the path with the object around the Z axis to start at a different place.
Also, I would but the animation end up to 100 for a smooth loop, if its going to be looping that is.

Toggle Cyclic? How do i do that?

Sorry, its in the Tool Shelf. Updated the answer.


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How to parent a cloth to a rigged mesh?
So, this is my setup:

I have parented a plane with the cloth modifier onto the mesh. However, when I play the animation, the cloth falls downwards, while the mesh continues on the path animation.
I want the cloth to follow the bird exactly like an advertising banner -- without  the mid air fluttering -- attached to an airplane.
PS : any other modifier-related help also welcomed.

In your case, I would just use a curve modifier. This doesn't answer your question, but it does get the result your looking for. I'll explain if your interested.

@cmomoney yes, please do :)

This doesn't answer your question exactly, but it might produce the result your looking for.
First un-parent the banner. Then clear the location(Alt + G). Add a Curve modifier and add your path as the curve object with Y as the deform axis. If the rotation is now wrong, rotate on the Y axis 90 degrees. Make sure your at the first frame of the animation, and move the banner on the Y axis until it is positioned behind the bird. Set a location keyframe(I, then "Location"). Go to the end of the animation and move the banner on the Y axis until it is again positioned behind the bird(type 302 into Y location it will get you close). Set another location keyframe. Go to the Graph Editor and under Key->Interpolation Mode choose "Linear".
So its not using a cloth simulation, but it should do what you want.

Interesting, I'll try that now

You certainly know the magic here! Thanks a ton, saved me a lot of rendering & baking time! :)

Mate, does the mess need to have a moderate to high poly count for this to work?

It only needs enough that it looks smooth(with smooth shading applied). It needs the geometry to bend right.


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How to apply subdivision surface to this geometry?
I have this simple geometry (I'm using also a mirror modifier) and I want to apply a subdivision modifier. When I add it the geometry gets all messy. I added some loop cuts but the result is not clean. The issue is in the zone where I made a bevel. What am I missing here?

Three points: 1. Subdiv and multires don't go well with ngons, 2. You might want to use "simple" instead of "Catmull Clark" as the algorithm and 3. you actually might have double vertices in your geometry. It's hard to tell without inspecting the file further. You might want to upload it to http://blend-exchange.giantcowfilms.com/ , then pasting the link into your question by using the "edit" link below it.

Also, this seems like a 'hard edge' modeling object, not suited for subdivision. You would probably be better off with a Bevel modifier instead, saving a lot of trouble, since it tends to play better with NGons

If you don't want to use Bevel modifier then change ngonal face of your mesh to quads, like in the image below. Then you won't have any troubles with subdivision.

Thanks for all the answers. Thinking about it better, maybe I really don't need a subdivision surface because, yes, it's an hard edge model. I can add only a bevel modifier and it works ok but I need one of the bevels to be bigger (the inside corner). Also, what if I want the part near the mirror to not be bevelled at all? How should I approach that? - I added the blend file to the question.

I think I'm getting to the solution. I made a bevel in EDIT mode only on the inside edge. Then I selected all the other edges except the one's near the mirror join and added other minor bevels. It seems that the geometry it's ok in this way. If this is the correct way to do it, the only concern I have is that I can't smooth the model after this because on the hard edges I get artifacts.

Use the edge split modifier then.It will remove artifacts in smooth shading.

Perfect @Mzidare. That's what was missing!


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Freestyle is not exporting with the object
Here is what it looks like in Blender Render (Not Cycles).

This is how I set it up.

Basically, I'm trying to export it, but it's not including the "Freestyle" lines.
When I open up the .dae file in Finder, it looks like this:

What is wrong here? I want it to be exported (COLLIDA .dae) with the black outline. I'm seeming to think that maybe the "Freestyle" is only for the Blender Render. Am I right? How would I go about getting the black outline included in my exported model? Is it an export setting I have to tick?
Thanks for any helpful answers.

Freestyle is a rendering engine: it "takes pictures" of the object, but doesn't affect the geometry of the model. The lines exist only in the picture. You should perhaps look for the Wireframe modfier or something like this.

Oh. Then refer to the end of my question. How would I go about creating this black outline?

maybe related: http://blender.stackexchange.com/q/562/19287

Original Question before: http://blender.stackexchange.com/q/50119/2843, related: http://blender.stackexchange.com/a/49235/2843

As mentioned in the comments the cartoon-style black outline is an image only effect done internally in post production over the rendered image, it does not affect the model nor is it part of the geometry, there fore it cannot be exported in any file format other than a rendered image, or at best as an SVG vector file (using the Freestyle SVG Exporter addon), you can then place over your image.
Where are you exporting your model in COLLADA too? Some Game engine? Other modelling application? You will most likely need to recreate the outline effect there in the destination software.
Otherwise if you actually want to have it in-model with actual geometry there are a few other options.

Either us a wireframe modifier over your objects to construct a cage-like structure over you mesh
Use a Bevel modifier on your mesh with a material index offset

Manually bevel your geometry and assign different materials
UV Unwrap your model and use an image texture, created in an external image editing software with the desired black edges in the correct places along the edges.

I am exporting to Xcode (which can be considered a game engine).

Well I don't know XCode but you either need to recreate the effect there using the available shaders or materials, or if you need it at the geometry level use one of the above options


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How to evenly distribute tiles on Cone
I'm trying to use a displacement map of shingles to apply evenly sized shingles on a cone shape (roof for a witch hut). No matter what I do I can't get the shingles to stay a consistent size over the height of the cone.
The cylinder shows the approximate size of the shingles that I am looking for, the cone is the shape I'm going for.
The final cone is my attempt at manually changing the UV map, but even if I get the scale correct, the texture "spirals" around the cone shape.

Cones are made largely of tris which don't play nice with either subdivisions or displacements. Try using a cylinder instead, and scaling down the top face really small so it looks like a cone, but the mesh is still quad-based.

This is what I did in the third shape and the distortion remains.

Ahhh,  I see. Not sure then. All I can recommend is the normal things - Check for dupes, apply scale, make sure normals are all facing the right directions, etc...

@vklidu here is the packed blend file, hope i did this correctly... https://blend-exchange.giantcowfilms.com/b/2OdQAjEV/

You didnt packed your texture, so I used one seamless from net. I don't have an issue with provided file https://imgur.com/BRdfOrE BTW next time please place given code into your question via "edit" link.

That demonstrates the problem I am trying to solve though. I want the shingles to have a consistent size from the top of the cone to the bottom. I have made some progress by marking every vertical edge as a seam. https://imgur.com/a/oFVIyw7

You need to go into the UV editing workspace, select the top row of your uvs, enable proportional editing set to linear (I think ?) and scale your row along X. This happens because while your uvs are the same size, the actual mesh is getting smaller along the Z axis. Elongating the uvs will help counteract that

https://imgur.com/a/bD1YOvY I've tried that too, this leads to other distortions and a "twisting" around the Z axis.

I thought you are referring to this https://imgur.com/FagWn5f

Theory
I don't think you have a chance to get there with this single texture and your mesh topology.
The only reasonable solution that came to my mind is to use some radial texture, like one based on fibonacci pattern.

Unwrapped from top view.
Pattern
To create such texture use this Brecht's script
(copy&paste into blender's Script Editor and Run Alt+P)
import bpy
import bmesh
import math

n = 100 # number of points
c = 0.1 # scale factor

mesh = bpy.data.meshes.new(name="Spiral")
bm = bmesh.new()

for i in range(0, n):
    theta = i * math.radians(137.5)
    r = c * math.sqrt(i)
    bm.verts.new((math.cos(theta) * r, math.sin(theta) * r, 0.0))

bm.to_mesh(mesh)
mesh.update()

from bpy_extras import object_utils
object_utils.object_data_add(bpy.context, mesh)

It creates vertices pattern. At row 5 of the script you can change number of vertices.

Model
Add Plane and model one Shingle, Object has to be oriented in positive Y direction so bottom part is on top. Rotate it on X axis a bit upward with shingles end so when they will repeated will be on top of other. For this quick Shingle I added Solidify and Bevel modifier.

Select Shingle and than pattern object and parent Ctrl+P them. Go to pattern's Object Properties > Instances > Vertices. Enable Align to Vertex Normal to get desired rotation.

Texture
To be able bake Normal map of this model you have to search for Make Instances Real, Join Ctrl+J them. Add another Plane above, add a new material and add Image node, click new, and keep this node selected (active). Go to Render Properties, choose Cycles engine, at bottom go to Bake > Bake Type > Normal > enable Selected to Active. Select joined Shingles than Plane and press BAKE. Save image as OpenEXR type of file.

Note: to create Bump Map - position camera above object and under Render Passes enable Depth pass or Mist pass. After rendering go to Compositor and tweak output of one of this pass. Or you can create a simple B&W material with Blend texture on Z axis for the same result. You can find a lot of answers here I guess.
Edit:
I just noticed ... baked Ambient Oclussion worked much better in this case. Result is similar to Depth. And you could already notice, unwrap from top view applies texture stretched vertically, so its good to compensate this by creating shingle a bit wider horizontal, so after texture is applied it looks in proportions.

Render doesn't use Displacement modifier, but Adaptive Subdivision (aka Microdisplacement) that needs a just a few faces for cone and beautiful details :)

That is a nice application of this pattern ! One might even be able to reproduce it procedurally :)

Such a beautiful solution..

Happen to have a tiling Fibonacci sequenced texture of roof shingles?

Oh my gosh, thanks! It was a half joke, I didn't expect anything, but thank you so much!

I'm not sure if you are notified about updates, so ... AO bake works much better here :)

I used the workflow suggested by vklidu but with the following script for vertex generation. Maybe this (more simplistic) pattern variation is useful to someone, so leaving it here:
import bpy
import bmesh
import math
from random import seed
from random import random

seed(1)

n = 12 # number of rows
c = 0.1 # scale factor
w = 0.21 # width of a shingle
s = 0.2 # size of a shingle row

mesh = bpy.data.meshes.new(name="Spiral")
bm = bmesh.new()

for i in range(0, n):
    m = math.floor((2 * math.pi * i * s) / w)
    for j in range(0, m):
        r = i * s
        theta = j * (2 * math.pi / m)
        bm.verts.new((math.cos(theta) * r, math.sin(theta) * r, -i * 0.05 + random() * 0.045))

bm.to_mesh(mesh)
mesh.update()

from bpy_extras import object_utils
object_utils.object_data_add(bpy.context, mesh)

The script generated vertices in rows while trying to fill each row evenly with shingles. The z-coordinate is changed with each row and vertices are also randomly shifted along the z-axis to give a more natural look when rendering top-down
I then used geometry nodes and the shader graph to add some variation to the shingle models and color tint. Looks wonky in the center, but this could be covered by a metal piece or similar on the final model.

Great :) ... probably you could add a screen of vertex's pattern  to be clear to followers the difference ... also you could elaborate further about geo nodes (since my A doesn't covering this technique it could be interesting). Thanks for your time :)


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How to avoid collisions of moving objects from point A to point B
I am using Blender to animate drone light shows.

Each drone is represented by an icosphere with an emission material.
A drone light show is basically a series of images and the drones navigate from image to image.

My workflow is to represent each image with empties. Then, the drones will move to all the empties in image 1 (I use dynamic parent for this, great plug in!), after a few seconds, the parenting to the empties on image 1 will stop, the drones will navigate to the empties in image 2, and parent again, etc until the end of the flight.
Right now, I am animating the movements between scenes by hand. So, after the end of an image, I look for the empty that is closest to the icosphere and navigate to it.
Of course, using hundreds of icospheres, there are bound to be collisions during these movements and I must correct all the movements by hand, moving icospheres and adding keyframes. This is all very time consuming.
What I am trying to achieve is the following (assuming we use 100 drones for this example).

1 select 100 empties as target positions.
2 Use some sort of plugin, or script, or animation nodes node tree that would calculate a path between where the icospheres are now, and where the empties are and would move all the icospheres to their new positions while maintaining a minimum distance between icospheres and not exceeding a maximum speed during the movement.

I have tried the "limit distance" constraint, but it does not work for our application. When two icospheres get too close, the limit distance constraint introduces jerky movements and very rapid speeds that cannot be replicated by a real drone. Also, the limit distance constraint introduces a lot of problems when rotating a complete scene or trying to do small adjustments to it.

Have you tried particles?

This is not complete answer, since I have an issue with distancing, but could be time saver for you to track "images".

I was thinking about Physics type Keyed to transit from one image to another.

... and use Force Field Setting > Type1 > Charge with Self Effect enabled. So particles should keep distance when Falloff is set right (Plane 2x2m, bigger face 1x1, smaller 0,5x0,5 ... Max Falloff is set 0,75 so particles on smaller are pushed away from each other.)

Anyway ... when animated use this script to make particles real and animated (or export as Alembic file and import back) ... adjust collisions manually if still needed.

 ... but even it is working for Physics type Newtonian, I don't see effect for Keyed.


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Detecting light intensity on surface with cycles nodes
Are there any methods for detecting the light intensity on the surface of an object using cycles nodes? Ideally including light from hdri and all other sources.

What is the purpose? Any render contains full colour depth info before save (if I'm right). So like Matte > Luminance Key in Compositor is what are you looking for?

I was hoping to use it as a driver for automating light dependent animations like pupil dilation. Perhaps the data could be extracted from each frame before beginning the next frame using the compositor and some scripting.

Hm ... from your Q I red -you'r looking for post-pro, but from this info it seems you want affect mesh or material animation before rendering, right? Please extend your Q via edit with these details (delete my gif if its wrong or too much :)

is this direction? https://blender.stackexchange.com/a/29094/2214


text:
change SOURCE of video?
B"H
Because of how brutal blender's video editing is for large resolutions i started editing a 360p version of my video. Then when I finished, I replaceed the source clips with the original format, 4k. Problem is after i replaced it, it appears clipped off, presumably because blender still thinks that the soruce clip is 360p while it really is 4k now (btw by "replace" I mean I renamed my 4k files to the same name as the 360p versions, copied out the 360p files and in the same folder location I replaced them with the 4k versions).
Any way to fix this? Maybe a script?

I'm not sure about your current issue, but what you are looking for are proxies.

It is hard to suggest something if we dont know how complex your VSE project is. Basically I dont thing there is much to do. Try select all affected strips go to VSE Timeline's side panel (N) > Strip > Transform > Scale X,Y and change it to something that fits your output dimension. It will set scale only to Active strip. Now with a mouse howering above scale values call contextual menu and choose "Copy to Selected". ... For a next time use "proxy" system in blender like suggested by Lutzi.

Fixing the scale
For the scaling issue, it is because Blender automatically fits the video strip to your render resolution when you add a new strip to the timeline, but not when you change that strip's video source.
You can use the menu Image > Apply to either fit, fill or stretch the image to your render resolution:

Using Proxies
As @Lutzi suggested, Blender already have a Proxy system which does essencially what you want: create a low resolution render of your files to let you work on them quickly and keep the original for the final rendering. It's all automated and you don't need to play around making new encodings yourself and swaping files manually. You should definitely use Blender's Proxy system. You can find it in the sidebar > Proxy tab:

Updates not showing up
As for your VSE seemingly not picking up the file update, it could be different things: you could just be looking at an old cache or proxy of the 360p version of your file.
If you enable a few cache options in the View menu, you could see what parts of your timeline are cached:

The caching options can be set in the sidebar > Cache tab, on a global and per-strip basis:

To force refresh the cash, use the menu View > Refresh All or press ⎈ CtrlE.
To go further:
2.1.4. Proxies & cache — Blender VSE Unofficial Documentation documentation

Even your answer is helpful. It does not answering OP's Q. The project is done (so proxy is not an option in this stage of work if is not started from scratch). Refresh cash is also helpfull, but not the problem here. The issue is that placed strips are using some scale (lets say 1). Just by renaming hires source keep video at scale 1. It means 4K video is now in VSE at dimension 10x bigger than 360px lowres.

True, I forgot about that x) editing the answer


text:
EEVEE Edge detect effect
I am trying to replicate an effect that one of my friends made and he was able to detect the edges of an object using Eevee all using nodes no wireframe modifiers or anything but the only way I can get close to being able to do this is with cycles. Video here.

As cubes (head), or scaled cubes (arms, notice the variations of the edge thickness for arms), you can compare the location to some threshold.
Edge detection: top line in the image below
We can take generated coordinates, and recenter them to -0.5/+0.5,
Get absolute of that.
Compare each coordinate to a threshold.
And detect the edge if more than two dimensions are above this threshold.
Camera facing effect: bottom line below
Compare the incoming vector to the normal using a dot product.
Keep only what is above a threshold.
Combine with the edge detection.

bless you, this worked like a charm

any way to make all the edge boxes the same size when using a mesh that isn't a cube?

If still cube based? Can try to look at the ratio object co / generated co if the origin is placed appropriatly. That should correspond to how the cube has been scaled.

ye i was saying like the arms and stuff are longer than they are wide and this makes the effect thinner there, ill try this. Thanks!


text:
How to make twisted bar? (Corkscrew)

With the reference image above. I want to make the bottom part which is twisted. At the top it go upward straight and the bottom part it goes narrow. I tried with the screw modifier but how can i make the top and bottom part. I tired to apply the modifier and extruded but the center point did not works. Any suggestion or help how it works.

Now you need to convert your curve to mesh, lower down the resolution of your curve and the steps of your modifier if you don't want a too dense topology. Then you need to model the top and bottom. I'm not sure what you mean with the "center point"

the other solution, if you want to do everything with curve, is to use a spiral curve, then you can extrude the top and bottom, and scale down the bottom vertex

You can't create the top and bottom without applying the Screw modifier. If you choose to apply, before applying lower down the Resolution of your curve and the Steps of your modifier in order to keep a low-poly topology. Then you need to model the top and bottom (with some extrusions).
If you want to work with a curve as much as possible you could create a spiral curve (you need to enable the Add Curve: Extra Objects addon, then ShiftA > Curve > Curve Spirals > Archemedian), play with the parameters in the Operator Box (don't create too many Steps if you want to stay low poly):

Then header menu > Curve > Set Spline Type > Bezier:

Then press V to change handle type and choose Automatic:

Bevel the curve in the Object Data panel > Geometry, keep Round selected and increase the Depth value:

At last, extrude the top vertex and the bottom vertex, and in order to reduce the bottom vertex radius, press AltS or type the radius in the N panel:


text:
How do I bend a Model with an Armature? (Worm, Caterpillar, Tentacle...)
I have created a model and added armature to it. I want to bend the center mesh in ^ shape. I tried to solve this with weight painting but it didn't work as expected. Is there a way to bend the model, so it looks like a walking caterpillar?
Any suggestions or help? Thanks.

Please show the attempted bend in a still image to improve clarity.  The bend is currently shown very briefly.  The current situation makes it difficult to see for comparison purposes.

@atomicbezierslinger i can pull up the bones so that it can bend. Any suggestion.

Please show the vertex density in edit mode.   Please give a internet link to a video that show the caterpillar movement you want. Are you trying for playful bone animation or high realism bone animation?

Is this a toy in two parts that hinges in the middle?

I'm not sure it will fit your need because it looks like your object is stiff and my solution is rather for a flexible caterpillar/tentacle kind of object. Anyway here is a solution with the Spline IK constraint. Contrary to other methods, you can easily stretch and twist your object in all the directions. Nota Bene: You should use several layers to make it easier to prepare:

Create a 5 bone armature (2 short, 2 long, one short), the first one will be the root, make the 4 other bones as long as the mesh.

Disable the Deform option of the root bone, it won't have any weight on the mesh.

Create a curve as long as the 4 front bones, subdivide it and make the vertices overlay the bones head.

Give the front bone a Spline IK constraint, choose the curve as Target, give it a Chain Length of 4.

As you can see, your curve vertices now control the bones head.

Switch your armature to Pose mode, select the root bone, then select the curve, shift select the bone, and parent with a ctrlP > Bone.

Now to make the control much easier and to be able to come back to a basic rest pose, you're going to create a second armature that will control the curve vertices: First create a bone for each head.

Switch this new armature to Pose mode, select a bone, now shift select the curve, go in Edit mode, select the corresponding vertices, and press ctrlH > Hook To Selected Object Bone. Same for all the other bones.

Now as you can see, the new armature control the curve vertices.

Switch the first armature to Pose mode, select the root bone, then select the second armature, select again the root bone and ctrlP > Bone. Now when you'll move the first armature it will move the whole thing.

Change the display of the first armature from Octohedral to B-Bone, Segment the 4 front bones (2 or 3 segments) to have a more flexible armature. Don't do it if you want to keep a stiff object.

Parent the mesh to the first armature with a ctrlP > With Automatic Weight.

Make sure that the Armature modifier is above the Subsurf. Enable the Preserve Volume option.

It should work.

Nice answer. Would emphasize the automatic weights, perhaps with an image showing result.

you mean an image of the mesh in weight paint mode?

Yep.   the weight painting in the OP is poor, hence the result. It also appears the `piller in q is maybe a toy that hinges in middle.

oh you're right, I missed it was a solid stiff object  :/

Not totally sure, have asked for clarification.

I'm not sure how it is supposed to bend with this kind of hinge though...

You could just hook the curve vertices to make handles, rather than bothering with a second armature? (You could even weight the hook influences)

the problem with simple empty hooks is that you can't reset to a rest position, but maybe I don't get what you mean?

No, you did get it, and you're right.

Suggestion

For playful low realism consider a lattice modifier. You may also you can consider a wave modifier.
Less Likely. Consider shape keys to create a depression to anticipate the bend.  Skinny limbs show less issues.  Plump limbs show more issues.  This is only in regard to extreme spine positions.
Archive your current file.
Create a new armature with many more bones to have more flexibility.  Make sure your vertex density is high enough for you artistic purposes.
Consider the back and front of the caterpillar as similar to the left and right human arms. (or Butterly Wings ) The human arms situation requires <<2>> sequences of bones plus a parent bone in the middle.  Your situation will probably require that as well.
The caterpillar movement is subtle in my sample video.  You may need to consider an armature with envelope weight.
Search on BSE for caterpillar or similar ... I think there exist discussions on similar topics.

can you plz shave with a basic shape and make it bend and let walk like caterpillar. Thanks

Oh no ... a negative vote ! ♂

@atek I did not understand completely what you wrote in the comment.  I have not seen any improvements to your question.  I may or may not see improvements to question.  I am not providing a tutorial.  We do not seem to understand each other.  We may be on different time schedules.  Good Luck.


text:
How to achieve this shape (Twisted bottle)
How can i achieve this bottle shape. I tried with the twist modifier and screw modifier both did not work for me any option or how can it work. Thanks

hello, do you have other pictures of the same bottle?

@moonboots no i just have this 1 pic

https://cad.grabcad.com/library/bottle-222 also https://bestinpackaging.wordpress.com/2008/12/06/smoothie-in-a-twisted-bottle/

Create the untwisted shape, it looks a bit curved on its sides:

Give the object a Lattice modifier, create the lattice object, scale it in Object mode (not in Edit mode!) so that it contains the bottle, give it some additional horizontal edge loops, create 2 shapekeys, select the second shapekey, go in Edit mode, twist each of its horizontal edges:

Whenever I use a lattice deform and the lattice is pre-scaled, the model gains that scale as well when it's associated, usually wrecking the relative sizing.  Does that not happen for you?  If not, which version are you using, and/or what am I doing wrong?  Happy to get PM about it as it is somewhat off topic.

Don't scale the lattice in Edit mode, only in Object mode, it may be your problem

But the shape is circular  cylindrical shape. Its a bottle.Not a flat.

It really is that simple.  Thanks.  Well there's that mystery solved.

@atek, I'm not sure what you mean, what I said is first scale the lattice in Object mode so that it contains the bottle, then maybe create 2 shapekeys to keep a square normal shapekey, then select the second shapekey, go in Edit mode and rotate each horizontal edge loop on the Z axis

If you scale in Edit mode it will also transform the object as soon as you give it the Lattice modifier, this is not what you want, and I guess this is what you describe,

I think they mean that the base mesh (before deformation) of the bottle is not elongated along a particular axis like the mesh you showed. However I don't see the problem since your solution can be applied to any kind of shape


text:
Making a hollow cylinder - Blender 2.80
I am trying to recreate the C64 logo in 3D, which roughly looks like this: C=
My thought was to create a cylinder the size of the C, then create a second cylinder the size of the inside of the C, lay them ontop of eachother and cut the smaller cylinder out of the large cylinder, then draw a square to cut off the right side of the new shape to create the 3D C.
But I'm struggling with the first part, making a hollow cylinder.
I've tried the knife project tool but it does not cut a hole into the cylinder. I've also tried to set a modifier but it says it cannot apply the modifier because it is set to disabled.
I'm using Blender 2.80.
What is a good way to approach this?

create a circle, extrude inwards, then cut it orthogonally with the knife?

@moonboots how do I extrude inwards? I'm fairly new to Blender. I forgot to add that.

Do you care about the clean topology? In case you don't, you could simply import the .svg, convert it to mesh and extrude. (https://upload.wikimedia.org/wikipedia/commons/5/5c/CBM_Logo.svg) That would be the simplest and most beginner friendly approach (although I  wouldn't call it modelling)

@rjg thanks for the tip. Although this is a good option, I'd like to learn how to do this the way it is intended, because I want to become good in Blender, and there will be things in the future where I cannot rely on having a .svg to extrude it.

https://blender.stackexchange.com/questions/46342/is-there-a-way-to-fill-the-area-between-two-circles/46351#46351

It really depends on what you want to achieve at the end, but you can begin this way:

Put your logo as a Background. Create a circle as large as the logo's C.

Press E to extrude, presse Enter, press S to scale down.

Activate the knife tool with K. To cut orthogonally, press C.

Select the vertices on the right and delete. You've got a C shape. But again, you'll probably need to rework on it depending on what you want to do.

Thanks. This looks like the approach I am after. I'm going to try this tonight and will report back.

I was really struggling with the knife tool. You might have added that you have to press enter after you make a cut in order to commit...

Really dependent of what you want to do once the base shape is done. Above two possibilities, but both may be wrong if the afterpart (if there is) needs a different geometry.
You can 'screw' + 'boolean', starting from a single edge:

Also you can 'spin' twice + 'bridge edge loops':

Spin is more manually done: make a spin for the inner part with x steps (starting from a single vertex). Make a second spin for the outer with also x steps (starting from another single vertex). Select all and in the menu in edit mode 'Edge>Bridge edge loops'.
The resulting geometry is different as the second, more manual approach, keeps quads. Depends on what you want to do after that.

Thanks for the answer. Looks like something I could use... if I only understood the answer... :( Maybe someday my skills are good enough and a revisit helps me understand this.


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How to make this texture? (Table Wood Texture)
I want to make the white lines appear on the legs of table in blender (just like in reference image attached). I am not good at procedural textures, if anyone can help. Thank You

This is a pretty solid video showing an easy way to do it - Just replace the brown in the ColorRamp with shades of grey. - https://www.youtube.com/watch?v=EbAdconaRJo

Thanks I would definitely take a look. Appreciate your help.

You could use a Wave Texture node before a ColorRamp, or another kind of texture that you stretch on the Z axis, use another texture before if it needs to be a bit deformed, but Wave Texture has a Distortion value:

That looks great. Thank You for the help, I really appreciate it.

no bump node!? i am bit disappointed...but yeah +1 because answer within 30 mins, nice screenshots....and damn easy to use answer! ;) I am so happy to know you Clark! ;)

that's just a beginning, I can make it more complicated but I wanted to stay as simple as possible, then the user can add bumps and glossy and everything of course, by the way, I know Robin and Batfinger are working on a Python version, but I count on you to show the molecular level of wood with geometry nodes, Albert


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How to make a plane with cloth physics, stick to another mesh like a tape?
I'm simply trying to figure out how does cloth sim work, by trying to make a plane stick to nearby sphere. Bizzarely, it doesn't work, at all. The spheres collisions have friction set to 80, both "cloths" have "shrink" vert group, but the plane just slides off it. Only circle does stick to the sphere. Difference between these is that, the circle was extruded out of the sphere.

Can anyone explain to me, what am I doing wrong ?
Edit:
This is what I'm trying to achieve, but without using pin group, so that the green line would deform with the deformation of the ball (For example, when the ball stretches, the cloth doesn't clip inside it)

can u pls show a sketch or picture what you are trying to achieve? Pin group might be what you want but it is not clear to me how your result should look like...!?

https://prnt.sc/4SRypbvfItDU
This is what I'm trying to achieve, but without using pin group, but a shrink factor

Maybe a ShrinkWrap could work for the green part? I don't think this will work without a pin group because the Friction value does not work like glue.

Figured things out at this point.


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Weird lines across model when rendered in low resolution
I'm getting these light colored lines mainly across the legs of my model but only when I render it at 96*96 px resolution (eevee). I only see them after I rendered them, they are not visible in the solid, material or rendered previews

Blend file:

I don't think the blend file you attached is the same as the one you show in the picture, could you please check?

Whoops I think you may be right, it was probably from an earlier save. I made an edit with the right file

96x96 pixels is extremely low resolution and I would expect to see visual artifacts. increase your render dimensions to 1000x1000 (at 100%) or even more and you will likely see improvements.

I suspect the image textures are scaled down. The light marks are the "background" color of the image texture you are using. They appear precisely where your seams are.
I'm sure there is some setting that does this and it may not be a default setting.
You could work around this by dragging in the seams in your image texture more towards the center or maybe find an option, so the image texture won't be scaled down. Alternatively you could render at a higher resolution and later manually scale it down.


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How to make cylinder to sine wave plane animation?
I'm trying to apply boolean cut to  a plane which turned into a cylinder  with simple deform modifier  and than turn that cylinder into a plane again (something like this which i saw in a Numberphile video).
First i create a plane, give it enough loop cuts than add simple deform, add rotated cube for boolean operation but when i apply boolean modifier, mesh looks like this.I don't want to apply simple deform modifier because i'll animate cylinder to plane transition.
What i am doing wrong?
Why does applying boolean modifier messes up geometry?

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.

There must be an smart way to do it but if you begin with a plane (object A), give it a Boolean modifier then a Surface Deform modifier with a second plane (object B) as Object, bind. Give object B a Simple Deform/Bend and bend 360° on Z. Here is what it gives when you unbend: https://zupimages.net/up/21/46/1q9y.gif

Dynamic Paint
Once you set up your plane with a modifier, and add a cube, go to physics tab and dynamic paint for both:

the cube - brush, paint color black
the plane - canvas, Image Sequence format,  increase resolution (it's just one frame so I increased it to 2048), frame end the same as frame start (again, just one frame), initial color white, set output to a place where you can easily navigate later and bake.

Now select the plane, in Material Properties > Settings change Blend Mode to Alpha Hashed or Alpha Clip. Modify the nodes of the material by adding an Image Texture node and loading the baked canvas. Connect its Color output to the Principled BSDF's Alpha input.

Now animate the modifier:

You can use a single object, by animating the alpha in the material.
As for your question:

Why does applying boolean modifier messes up geometry?

Because you apply it before the Simple Deform modifier, so you apply it on the flat plane.

..Late to this, but an option would be to create a plane, with a sinusoidal top edge:

Enable the shipped Add-On:  'Add Mesh: Extra Objects', if it isn't enabled already
Create a Z math-function surface, sin(pi * (x - 0.5)) as shown..

Nick the middle edge from it, and extrude down in Z..
Scale the bottom edge to 0 in Z

Now you can give it the Simple Deform > Bend as before.

You can scale the curve in Z, or the whole plane in either direction in Edit Mode, while looking at the deformed result. Its top edge will still be a sine wave..

love your solutions!!! +1

I was thinking about this - since the animation represents a mathematical relation, you can just use mathematics to compute the end result. :)

@MarkusvonBroady I like the ingenuity of your solution, though :) It's almost certainly just me.. but  I always find Dynamic Paint a bit painful? I've gotten slightly phobic.

I didn't use dynamic paint much, so this was an excuse and went surprisingly smooth. :)