text:
How do I create voxel (3D pixel) art in Blender?
I appreciate if anyone know how to build this model by which software or online platform? It is much thinkful to good to know about this.
Alternatively, how to build this model easily by some manner or technique?
Thanks a lot.....

I've edited my answer in order to answer your question about tilted objects

it would be helpful if you mentioned how you will use the end product. does it need to be a VOX file or an OBJ file with .MTL? or just a simple render out for NFT image?

There's a modifier called Remesh (in Blocks mode) that allows you to create this low-poly style from a round object (the Octree Depth value defines the block size), it may help you. When you're good, just apply the modifier:

For tilted object, as you show in your post, just apply the rotation of your object (CtrlA):

Start a new project.
Go to Geometry Nodes tab on the very top of the Blender window.
Press a button in the center of the screen to add a new node tree:
ShiftA search for node Instance on Points. Drag it onto the existing link to insert as intermediary step. Drag the Instance input socket to the left, and drop to get a prompt for a new node - choose Cube primitive:

Go back to the Layout tab.
Tab Enter Edit Mode.
AltZ for X-Ray mode:

Everything should be selected like on the image above - if not, A.
MA to merge vertices, so there's just one.
ShiftTab Enable Snap
ShiftD to create new vertices and move it around. If you place a vertex by clicking, you can still move it again by G:

Consider turning on Cavity:

Now you can preview your model by AltZ switching X-Ray mode:

In order to color your mesh, you will have to add Realize Instances node, and apply the modifier:

A tutorial on low poly models - linked to the timestamp about coloring:
Learn Low Poly Modeling in Blender 2.9 / 2.8
In future you may want to remove internal faces:
How to combine multiple cubes with double faces?

You are looking for a Voxel Editor like these (examples):
KenShape
Mega Voxels
Qubicle
VoxEdit

MagicaVoxel is probably the most popular app to create 3D-pixel models like one you presented.

Remesh modifier is the easiest method
This might not be convenient however here is an alternative method. Using Minecraft(yes I'm talking about the game) as base editor

Create a superflat world
Make your pixel art in that world
Save and exit Minecraft
Open
Mineways then open your map tweak settings then export as .obj file
Then import .obj file in blender
In 3d view MCPREP tab
click prep material
This will apply block materials
Then change materials as you wish

This method isn't free because you have to pay for the game


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Seamless mesh array modifier
I have symmetrical mesh which I want to be used as tiles but as you can see on the picture there is a seam when I use the Array modifier is there a way to be made seamless?

hello, in the modifier have you enabled the Merge option?

Yes but it doesn't help

increase the merge distance, however, I don't think those are perfectly seamless.

please share your file: https://blend-exchange.com/

 There you go

The reason why your mesh doesn't tile well even though you make it symmetric with mirror modifiers is that mirroring only guarantees the vertices of mesh borders will meet, but it doesn't guarantee any smoothness of the resulting connection. You could do something like scaling the border down on Z axis with proportional editing enabled, or you can use a Smooth modifier. Also I recommend using Weld modifier instead of Mirror/Array merging. You can limit smoothing to a vertex group, though you should probably smooth that group if you need multiple iterations:

Also I just spotted you have some doubled vertices, select all vertices and press M, B.

Alternatively: tile manually, remove a connecting section and bridge edge loops with a smooth interpolation, then cut out again only the part that is supposed to tile and repeat your modifier stack:

Thank you for the solution.

Usually the standard way is to create a tiled texture and use that texture in a material for a mesh instead of making the mesh tiled. It's kind of industry standard. Also your mesh is not strictly tiled if you look closely

source: Stack Exchange

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

sort: votes


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My custom driver function to calculate the length of a bendy bone sometimes has jittery output
I have written two custom driver functions that both do the same thing. Return the actual length of a bendy bone taking into account its curvature. A custom function was necessary because the default length property for a bone just gives the length from head to tail disregarding any curvature that is part of the bendy bone.
Of the two functions the first uses self and calculates the length of the bone the expression lives on. The other one uses two arguments, the first being self so the armature can be derived and the second argument being the name of the bendy bone whose length needs to be calculated. Both of them use the same logic for calculating the final length.
My issue is that there seems to be a problem with updates. The output is mostly smooth with the occasional random jitter. This is not dependent on a specific value or even a specific time. I feel this is related to the dependency graph because it seems to resolve itself on scene update. If it happens when I manually manipulate the playhead even letting go of mousedown is enough to refresh the scene and fix it. If it happens during animation playback and I manage to pause on the right moment, just selecting a different bone is enough to fix it.
I don't see any mentions about circular dependencies in the terminal and it also does not feel like the value lags. When doing research I read about drivers having issues with automatically updating when custom properties they depend on are updated through python. Since this function does not use any custom properties it did not seem relevant. I also read about possibly having to tag objects for update but this feels odd to me because a) it works most of the time and I would expect it not to work at all if this was the case b) which objects should I tag for updates? The bendy bone whose length I need may be part of a really complex rig where many things influence its final shape and therefore length.
I have also supplied a blender file with a working example that shows this behavior. The scene contains an animated bendy bone. Right next to it is a bone whose length is driven by "bbone_length_by_name". As you play the animation you will see it scale up and down and occasionally glitch out.
Blender file
I have also added a link to a short video file that shows the jittery behavior. Since writing this post i've noticed that manipulating the viewport seems to make the jittering worse. If I leave the view static the jittering is less.

mp4 link
Since I wondered whether it was a display issue ive also printed the value to the terminal. As you can see there are weird jumps that last just a frame. So its not just a display issue, its actually because the values from the function are wrong sometimes (ive marked a few). These frames are not fixed btw, the spikes are random each playthrough.

Here is the code:
import bpy
import math
from mathutils import Vector

def get_bbone_segment_location(target_bendybone, segment_index):
    # in worldspace
    bone_armature = target_bendybone.id_data

    matrix_segment = target_bendybone.bbone_segment_matrix(segment_index, rest=False)
    matrix_final = bone_armature.matrix_world @ target_bendybone.matrix @ matrix_segment

    return matrix_final.decompose()[0]

def get_bbone_segment_locations(target_bendybone):
    location_list = []
    num_segments = target_bendybone.bone.bbone_segments

    for index in range(num_segments):
        location_list.append(get_bbone_segment_location(target_bendybone, index))

    return location_list

def calculate_length(points):
    total_length = 0.0

    for i in range(len(points) - 1):
        distance = 0.0
        point1 = points[i]
        point2 = points[i + 1]

        distance = (point2 - point1).length
        total_length += distance

    return total_length

# function to use on the bendy bone itself where self can be used for the target_bendybone argument
def get_bbone_length(target_bendybone):
    location_list = get_bbone_segment_locations(target_bendybone)

    return calculate_length(location_list)

# function to use on another bone within the same armature where the name of the bendy_bone needs to be supplied
def get_bbone_length_by_name(self, target_bendybone_name):
    bone_armature = self.id_data
    target_bendybone = bone_armature.pose.bones[target_bendybone_name]

    return get_bbone_length(target_bendybone)

bpy.app.driver_namespace['bbone_length'] = get_bbone_length
bpy.app.driver_namespace['bbone_length_by_name'] = get_bbone_length_by_name

Any help or pointers would be really appreciated because I have no idea how to go from here.

I am not able to reproduce a jittery behavior. Tested on Blender 4.0 and 3.6.5. Try opening the file in older version of Blender.

@RumenBelev Thank you for taking a look! Yes it differs per system. Ive had various people test it and some had trouble reproducing it. The original setup was created in 3.6, i've tried it in the latest 4.0 as well. The problem is not with Blender itself (nor its version) but in the setup. See my answer below.

It looks like the jittering was caused by a race condition in what was evaluated first. Either the final bendy bone shape or the calculation for its length. As Rumen pointed out it seems to differ per system how badly the jittering occurs. I've heard this from other people who tested this as well. On my system it was very prevalent as the embedded movie shows.
What needed to happen for this to stabilize is to force the evaluation order. You can achieve this by creating variables on the driver itself (so not in the custom driver function) that reference the transform channel of the bone whose length you want to calculate.
You don't need to use this variable anywhere, creating a reference to a transform channel is enough to trigger the evaluation of that bone. It is important you use a transform channel and not just a property on the bone in question since the latter won't trigger an evaluation.
In the example video I used it in its final purpose: to have a bone sliding along a bendy bone chain consisting of three bones that constantly vary in shape. You can see the bone that rides it has a fixed position along the total combined length, smoothly crossing over from bone to bone as if its a single unbroken chain. To be able to do this is what I needed the actual length of a bendy bone for. As you can see its fully stable now.
mp4 link

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


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Geometry Nodes: Pick instance by tile size
I want to put instances on tiles, picking from a collection with cubes of various sizes, so that I can fill the tiles with a minimum number of instances.
For example I have 3 cubes:

size 1×1×1 ▪
size 2×2×2 ◼
size 3×3×3 ⬛

Now I have an object with a geonode tree:

if a tile size ($x$ and $y$ lengths) is 1×1 then it should automatically pick the ▪ 1×1×1 cube instance on this tile. If a tile size is 1×2, then it should pick 2 cubes of size ▪ 1×1×1;
if a tile size 2×2 it should pick a cube size of ◼ 2×2×2;
etc.

I think the solution will largely depend on if you want to support bigger cubes, as currently geonodes don't support recursion, but just for 3 cubes you can simply duplicate a setup twice.


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Spawn unique instance per point
I'm trying to instance a collection of images, such that each point has a unique image.
When using a mesh to points node to create the points, everything works fine when set to Vertices, Corners, or Edges. However, when setting it to Face mode, it will only spawn the same image on every point.
Correct Behavior when set to vertices mode:

Incorrect Behavior when set to face mode:

Current Node Setup:

Is there some sort of separation that needs to happen with the points so they are unique index values?
File Included:

please do not ask more than one question. Mabey read again: https://blender.stackexchange.com/help/how-to-ask. You can open as many questions as you like - so just copy it and open new questions. thx for your understanding.

It was not meant to be a multipart question. It is meant to be singular, with the additional information to provide context on where i’m headed so that if it turns out that it would be a waste of time to set it up one way because I would then need to redo it all if that basic idea can’t work with the overall idea. That’s why I didn’t ask how to do those things, merely mentioned my future goal. I will try to phrase that more clearly next time but was aiming for brevity.

If you take a closer look, you would have seen that this isn't a bug. You have checked "picked instances". So Blender does this, because you didn't plug in any instance index there. And it seems to take the index of the source element (which is a cube's face/vertex/edge). Because you deleted every face except one, the index is always 0.
You can check this out if you just mute your delete geometry node, because then you will see more than one image.
You can use the realize instances node before the delete geometry node to get different instances picked by Blender.

How do I get from that knowledge to getting this to function? If the index of each face is 0 on each cube, then what would I do in order to renumber the values of each face? There are 3 faces left because there are 3 boxes that have their other faces deleted. How can I get each of those faces to be considered part of a new grouping of index values?

just put a realize instances node before the delete geometry

Thank you! That was what I needed. I see why I was so confused now. When I have "Separate Children" checked on the collection info (which I did in my original file, before creating a duplicate to ask this question). It shows the instances in the viewer: https://imgur.com/ehdKHba
However, the images are all the same per point. I don't understand why instance index values don't work as a possible solution to the same problem. Does the spreadsheet info indicate this? I feel like there's a fundamental idea at the core here that I'm missing.


text:
How to stop flickering in dark animation?
Hi – I’m having problems with flickering in my scene when I render the animation (there's two renders in the video I linked to, the first with no BG light and the second with plenty). I’m going for a dark aesthetic, lit with lamps (area lights - the lamp you see), a point light (in the rear), and now some general background colour to lighten it.

(Above two first frames of the animation)

(Above first 4 seconds as GIF)
I started with just the lamps and a bit of back lighting, but noticed a lot of flickering noise in the shadows when I rendered so progressively added more light (see below). Things I’ve tried so far:

rendering with more samples. This helped slightly, but it’s a long animation so I can’t go too high; I got to 500 samples, but still saw significant flickering.
increasing max light bounces (didn’t seem to have an effect).
lowering Post Processing > Dither to 0 (seemed like something that could help; no effect)
checked Denoise seed is not animated
changing Denoisers – I’ve tried Optix and OpenImage, as well as reducing Clamping Strength to 0

Finally, after reading a bit, I realised the scene was much too dark, so I started adding fill light to the background. In the second render I have the background colour set to white and the Strength to 2, and it’s still flickering in the shadows – less, but it’s still there.
This isn’t an isolated thing, either – if you look at the texture of the dominoes here (which are static textures), it flickers quite a bit. Same with any glass texture I render as an animation.

My guess is it’s the denoising, but I’ve no idea what to change to make this better.
I’m using E-Cycles 3.3.0 with Cycles, but have rendered mostly in standard Blender to make sure it’s not an E-Cycles thing.
Should I try rendering the animation out and denoising it in other software? Does anyone else have this problem with dark-ish scenes, and if so have you found a solution? Should I go much lighter and darken it in post?
Many thanks for any help you can give.
Andy

have you tried decreasing the maximum bounce? Usually a clean render is a combo of good lighting, tons of samples, and a good composite.

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.

Hi @ruckus - just decreased the max bounces (by half) and no discernible effect. Do you know of any guides I could look up for this issue (rendering somewhat dark scenes)?

Hello @Duarte - thanks for the comment. Correct me if I'm wrong, but I don't see any way to upload gifs directly when writing a post, and I couldn't see any reference to this in the link you gave. Is there an easier way than linking to YouTube? Since I'm referencing output (my renders), a screen recording doesn't seem the most logical.

See How to upload an image to a post? or GIF There is a post specifically about authoring GIFs for Stack exchange. Videos are generally frowned upon here for various reasons including but not limited to being an external service that may be erased or lost, bandwidth, time it takes to watch, not being indexable or searchable, thus not helping future users with similar issues

When testing your animation output, first render the animation as PNG files, assemble them together in a video editing tool (e.g. Blender...) And play it in that tool - if the flickering is not there, it means the flickering is caused by the video encoder (the keyframes refresh the screen with more accurate data than one obtained by changes in non-keyframe frames, and this accurate data may be brighter or darker than the approximation).

Thanks @DuarteFarrajotaRamos - I understand the reasoning to keep media on BSE, and will do so whenever possible in the future. In this specific use case, however, it doesn't make sense to me - I'm trying to show details in a final render, not a process video, so reducing it to less than 2mb would likely destroy the quality needed to show this.

Hi @MarkusvonBroady, thanks for the reply. The video I linked to was rendered as a png sequence in Blender then imported to After Effects (still flickering) and exported vie Media Encoder (still flickering in final output), so I'm fairly sure it's not an artefact in one part of the process.

I think your problem comes down to: low samples + camera movement + denoising. Either due to camera movement the temporal reuse of samples doesn't work and so colors differ (with more samples the color averages would converge) and/or the denoiser has a different input, so also the output is not deterministic and it is as if you animated seed...

@Andy sorry you're having such trouble! Here is an external resource that I think could help you.

Hi @MarkusvonBroady - appreciate the tips, but I'm afraid I don't know how to change either of those. Camera movement - I guess the fix would be to stop the camera moving? Which wouldn't really work for me. And I haven't changed anything to do with the denoising input (would also be strange, as this has occurred across several versions of Blender / E-Cycles, with default settings after reinstall). How can I check this? Many thanks for the help!

Thanks @ruckus - I think if I'm going to buy some external software for this it would be DaVinci Resolve, as I hear the denoising is pretty spot on. Thanks!

I had the same issue. Its caused by default denoising in Blender, that's done Frame by Frame so in an animation you will always see some "artifacts" between frames.
The best solution I've found was a step by step process inside blender that I found in a forum (https://devtalk.blender.org/t/taking-a-look-at-optix-7-3-temporal-denoising-for-cycles/18656/103)
The steps are:

Change Output File Format to OpenEXR MultiLayer
Check the Combined, Denoising Data, and Vector pass in the render layer settings and deactivate denoising
Render the animation
Ensure the OptiX Denoiser is selected in Blender Cycles settings and run bpy.ops.cycles.denoise_animation() in the Python console (And wait as Blender will freeze while it denoises the animation)
Done (the EXR images now contain the denoised image sequence)

This workaround worked for me, hope it will work for you!

For those who wonder, bpy.ops.cycles.denoise_animation() used without arguments will use current scene settings including the frame range, and modify the saved files on disk.


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How to use the geometry proximity node as snapping tool
I want to use geometry nodes as a snapping tool. Here is a simple example of the problem:
The geometry proximity node uses the shortest distance. How can I make it use the distance in the direction of the normal of each face?

small shape I want to deform:

big shape I want to snap to:

result of geometry proximity using the shortest distance:

I have added the file, I hope I shared it correcly in this way.

In this case you would have to use the node Raycast:

With this you can feed the direction of the ray with the normals of the faces, whereby along this the position of the nearest object can be queried and used as position for Set Position.


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narrow view, model to big. viewport to small
The view is very narrow, see image.
Also the models disappear...
How can I make the view bigger?

It looks like a Clipping issue, open the N panel > View > View > tweak the Clip Start and End values

https://blender.stackexchange.com/questions/5201/how-do-i-increase-the-render-distance https://blender.stackexchange.com/questions/8553/why-does-part-of-my-model-disappear-when-i-zoom-in-on-it-in-the-3d-viewport

Side note: I don't have access to Blender right now, so I will do what I can from memory and what I can find online. Do let me know if this need details, and I'll edit my answer later once I'm back to my personal workstation.

Unless a technical reason prevents you from it, you should scale down your scene to a reasonable size, even real-life size if possible.
If you can't, then change the viewport and camera clipping planes.
Scaling the scene
To preserve every object's position relative to each other and within the 3D world, we'll can use the 3D cursor to scale them down from the world center.
First, make sure the 3D cursor is at the world origin by pressing ⇧ ShiftS > Cursor to World.
Then, set the pivot point to 3D cursor.

To help see the scale, I personally like to create a cube that's the dimensions of a human:

⇧ ShiftA > Mesh > Cube
↹ Tab into edit mode, select all with A, press GZ1 and ⏎ Enter. This should have moved the cube to the floor.
↹ Tab back to object mode. In the viewport sidebar, Item tab, Dimensions section, set the dimensions of the cube to X and Y: 45cm, Z: 174cm. This is the average of a human male.

Now press A to select all your objects, hold ⇧ Shift and click your human cube twice to deselect it.
Press S to enter the scale modal operator, and move your mouse around to scale down all the selected objects. Once you feel like their dimensions are logical compared to the human cube, use ⏎ Enter or  LMB to validate the scaling.
Press A to select everything again, then ⎈ CtrlA > Apply Scale. This is to prevent issues down the line.
Change clipping planes
If Scaling isn't possible, go in the viewport sidebar, View tab, Clipping. You should see start and end clipping values.
End clipping is how far you can see, start by updating this one first. Once done, you should also update the start clipping, as having them too far from each other can cause issues. A safe bet is to set it to whatever the greatest value you can without seeing any problematic clipping.
Once you are done with that, select your camera. Press numpad0 to set your viewport into camera view. If you have clipping issues, you need to change that camera's clipping settings too.
In the Properties editor > Camera data tab, clipping panel, you can change the camera's clipping there.


text:
How to decrease the number of tiny islands in Smart UV Project for photogrammetry models?
Smart UV project is making some pretty terrible UVs for my photogrammetry scans:

Lots and lots of tiny islands.

I already tried changing the smart UV project settings.  I need margin at .1 so I can edit sections in Photoshop later.  Changing area weight doesn't do anything.

Flat sections of mesh translate to UV great.

But anything slightly complicated and BAM, tiny UV islands everywhere.
Surely there is a better way to do this.  Any ideas?  Thank you very much for your help.

The cleanest way would be to separate the objects, retopo and then UV unwrap.

If you have issues editing your UV layout in an external program, you might keep a small margin and increase the exported UV layout's resolution instead:

Also, if your output render engine supports multiple UV sets for one object, you might just make several UV unwraps which each gives more pixels to different areas. You could have one UV Map for the house for example, and one for the other parts.

For rendering in Cycles, you will just have to use the Input → UV Map in order to specify which UV Map to use in your shader. You can have one node for each UV Map you need:

Or play it the "Divide and Rule" way:
Just split your mesh into different smaller objects and give them what they need in UVs and textures.
In order to split: go in edit mode, select the mesh you want to split, then hit P → Separate Selection. What you selected will be sent into a new object. Repeat as much as you need.

Hmm there's a thought.  I have a hard limit on texture resolution of the end product, but maybe I could start with a very high resolution texture, edit it in photoshop, then scale it down.  Thank you.

I edited my answer, and this might give you the trick you need. Check it out.


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How to fix my blender not rendering?
Hi I am a beginner in blender, it worked fine until I tried to render a video from video editing section in blender and after that my render stopped working, here's before:

And here's after:

Recommended way is encode after the actual rendering is done. Render to an image sequence perferably OpenEXR and use ffmpeg or Davinci Resolve to compile your image sequence into a movie clip. If you would like to stay in Blender, see: How to convert image sequence to video using the VSE? BTW: Please take the [tour] to learn about how this site works.

It seems to me that you're stuck on the render result window and all you have to do is to close this window by pressing ESC or the X button in top-right of the window?

https://blender.stackexchange.com/questions/67490/why-does-my-object-not-show-up


text:
Rendering Borromean rings
The Borromean rings are a set of three rings that are linked, but do not interlock:

The structure cannot be pulled apart, but cutting any one of the rings allows you to separate the other two. They cannot be physically constructed with regular tori in three dimensions, you have to deform the rings like this:

Or this:

Which might look like perfect circles from one viewpoint only.
These are not Borromean rings, whatever the listing says, as they actually interlock and cutting one of them does not release the other two:

I would like to render an 'alien artefact' that appears to be a set of Borromean rings made out of perfect circles, indicating that they somehow stretch into additional dimensions.  The rings don't need to move in relation to each other (although that would be amazing), but the camera does need to pan around them, showing them from several angles.  I was thinking to use the geometry of the 'false rings' from the last link, but shade them in such a way that they render some parts of the structure in the wrong layer order to create the Borromean effect, but I couldn't think where to begin to make something like that happen. Any suggestions?  Any rendering engine would be acceptable.

Hi :). Do you want a perfect result using deformed rings (second+third example), or slightly imprecise result but perfectly round rings (last example)?

It's more important that the rings appear perfectly round, although I'd be interested in either approach.  The rings don't have to actually be perfectly round in the geometry as long as they can be made to appear so.

Before anybody goes on a wild-goose chase: "It turns out that rigid Borromean rings composed of real (finite thickness) tubes cannot be physically constructed using three circular rings of either equal or differing radii. However, they can be made from three congruent elliptical rings."  https://mathworld.wolfram.com/BorromeanRings.html

@RobinBetts yes, this should be clear by the fact the red ring is entirely above the green ring (1, 2), the blue ring is entirely above the red (3, 4), and the green entirely above blue (5, 6): https://i.imgur.com/si93YII.png so it's an illusion similar to Penrose Stairs.

@MarkusvonBroady.. instinctively that's what I thought too.. but by that logic, it couldn't be done with rigid ellipses either? I think 'above' isn't as clean a concept, here, as in the stairs. Free rotations have to be considered.

@RobinBetts you're correct, ellipses as shown in the question have the ability to slide inside each-other.

Here's one idea: bend the rings locally, maintaining their dimensions not parallel to the camera's ray; the easiest way to do this is to position the rings on $z = 0$ plane and orthographic camera looking perfectly vertically down - this way all camera rays are looking down, and so the displacements can be safely done if they're limited to the $z$ axis:

Custom Group:

While the apparent thickness and position of the rings is as if they were flat, you can still see deformations through both Eevee shadows and shading (brightness based on surface angle regardless of how many light rays can hit the surface):
 Falloff: 0.150, Displace: 1.237
Of course the above is the worst example, it gets better with larger falloff and reasonable displace:
 Falloff: 0.400, Displace: 0.105
The falloff can overlap (though if it overlaps by A LOT then it starts to have the same effect as decreasing the displace):
 Falloff: 0.550, Displace: 0.105
You can decrease the displace so that the rings overlap, if I decreased the displace any further below, the rings would start to visibly overlap:
 Falloff: 0.550, Displace: 0.044
Unfortunately such overlap severely reduces the shadows which you actually might want… Here's a GIF of two last operations seen from a side:

You could join the curves before displacing (and in the same order as after displacing!), and bevel them, then after displacing and beveling sample the normal from non-displaced tori (learned this word here) - remember to use the nor attribute in your shader:
 Falloff: 0.550, Displace: 0.105
And finally if you go from Render shading to Viewport Shading, which has simpler rendering not involving shadows:
 Falloff: 0.550, Displace: 0.044

To consider

If you don't need the rings to cast shadows on themselves, but would like them to reflect the environment, I'd go for compositing, rendering each ring separately, and then overlaying on on top of each-other by a few checks (if not red: display green, if not blue: display red, if not green: display blue).
If you want to use perspective camera, the setup should still work, you just need to calculate the ray direction and displace the vertex along that direction, rather than $z$ axis.
You can add more rings, though positioning and fine-tuning the falloff and the displace isn't exactly trivial:

Or... do it in Inkscape.   (Just kidding,, nice answer :) )

I tried Inkscape yesterday, I didn't even know how to change the page dimensions or rotate an element ☠

Here is a simple solution:

First I just create a circle and move two selected points. One up and one down. These points are the intersections between the circles.
In order for the Z position to be smoothed, I also use the Blur Attribute node, which is available from version 3.5.
Then I simply instantiate this circle on the points of another circle which has only three points.
This is optional, but I think it looks even softer this way: You can convert the curves to Bezier so that they end up smoother.
And at the very end, I convert these curves into a mesh using Curve to Mesh.
(Blender 3.5+)


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How to export Alembic Mesh Sequence Cache to FBX?
I am making demolition animation for a realtime render engine that does not support Alembic, so I am trying to convert Alembic import from Blender to FBX, but only the first frame of the animation gets exported to FBX, so I was wondering if there was a way to convert the Alembic Mesh Sequence Cache so that all the animation gets exported to FBX?
Thanks in advance for any help!
Gilles

There's a tool for Maya that does this- https://github.com/aniketrajnish/Alembic-to-FBX-File-Maya/

Humm. If we take into account that alembic is a cache format, similar to a dmm or pc2, what should be done is to export the first frame as .obj, and then create a dmm / pc2 of that sequence. I do not know if it works well ... The fact is that alembic separates the different meshes, so you must make a "key shape" for each component, not as a cache. This you can see if in the timeline, each frame is marked, which does not happen with alembic. That's where things go ... (I'm not very expert in Blender, but that will generate a considerable size in Mb ..) Besides, each software company has "its peculiarities" when it comes to interpreting a FBX.

By the way, I export from Maya to Blender a alembic in Ogawa format, and it looks painful of geometry ... I do not understand that! LOL

AFAIK you can't do this, at least not for the generic case you describe. A mesh in Alembic can potentially be completely different from frame to frame, including a different topology. I don't think FBX even supports this.

I found a easy way to do it
add MDD add-on from preference to blender
export the
Select the object you want and export the MDD,
Import the object without animation,
Select it and import the MDD,
And again export the object as fbx,
Done!
Watch this video I made.

Thanks for the posts. This is not a regular forum, according to site rules links to answers are not answers if the link goes missing your answer becomes an empty shell without content. Answers should be substantial and stand on their own without relying on external data like links, videos or images. Instead of having users go through external links, either transcribe essential parts of the process here, linking the source, or posts these in the comments section instead.

If you read my replay it give the answer, the video is just for more clarifying.

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


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How to make a bone active?
I am trying to select a bone and make it active in 2.80, so I can run an operation on it (connect it to its parent), the bone gets selected, but does not get active, as shown in the picture, when active, the name of the bone appears in the interface, anyone has an idea what might be the problem here?

Here is the code I use…
bone.select = True;
bone.select_head = True;
bone.select_tail = True;
bpy.ops.armature.parent_set(type=‘CONNECTED’)

Thanks in advance
Gilles

API properties.
Set the active bone with arm.edit_bones.active = bone.  However propose there is no need to use the parenting operator, can rather set the properties, parent, use_connect
Python console code with armature arm in edit mode.
>>> arm
bpy.data.armatures['Armature']

>>> bone = arm.edit_bones["Bone"]
>>> bone2 = arm.edit_bones["Bone.001"]
>>> # active edit bone
>>> C.active_bone.name
'Bone.001'
# set active edit bone
>>> arm.edit_bones.active = bone
>>> C.active_bone.name
'Bone'
>>> bone2.parent = bone
>>> bone2.parent.name
'Bone'
# check if connected.. nope
>>> bone2.use_connect
False
# connect
>>> # connect the bone
>>> bone2.use_connect = True
>>>

I tried arm.edit_bones.active = bone before, but not in the right context, now it works, looking at the other code as we speak !
Thanks a bunch for the reply, I really appreciate it !


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Is it possible to save Grease Pencil shapes to the asset browser, then load them back into a different GP object?
I am working on a Grease Pencil workflow, and I was wondering if it is possible to save a GP shapes from within a GP object to the Asset Browser, then from the Asset Browser back into a different GP object???
Imagine I have a bunch of drawings for a character, I create a blank GP object, and from the Asset Browser I drag and drop different drawings on different frames as a startup to create an animated sequence, anyone knows if it is possible, and if yes, are there any tutorials on that subject ?
Thanks in advance for any help!

Following this patch and the linked revision which has shipped, it seems support for what you describe has made it.

Yeah, Matias Mendiola says that it's coming soon in his BCON22 talk! :)


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Moving keyframes
I'm using Blender 2.8 and trying to create a simple animation, a jumping lamp. I was using the auto keyframing. After I had a few keyframes I noticed that one movement was too slow, so I wanted to move all keyframes after frame 40 a bit closer to the previous ones.
I can't seem to move the keyframes on the "Lamp RigAction" row. If I box select all the frames I want to move and move using G key, the Lamp RigAction keyframes remain in place. If I delete all and then play, most of the animation is still there, the jump itself (but the movements of the lamp shade seem to have been deleted).
I'm a beginner and don't know what's going on. But I would like to know so I can adjust my future animations.

could you please share your file? https://blend-exchange.giantcowfilms.com/

Doesn't seem to work. I get a message box saying "error uploading". I'm using this URL: https://blender.stackexchange.com/questions/139423/moving-keyframes. Is that correct?

First of all be sure to perform keyframes edits in pose mode, not in edit mode or object mode.
As you have got this little arrow on, the dopesheet shows (and select) only keyframes of selected bones.
So, if you want to move only bones keyframes, in pose mode select all bones which you want to move, set the time cursor on frame 40, Ctrl click on the right side of the time cursor: this will select all keyframes after 40. Then press G and the amount of frames you need, then Enter.
If some of the keyframes are not bones of the rig, disable the little arrow and box select all keyframes you need to move.

If you click on the left every keyframe before the timeline will be selected.

Thanks! I clicked the arrow and then more stuff appeared and I could move around the keyframes. And now, even if I click the arrow again, I can still move the keyframes. The Lamp RigAction row (yellow for some reason in my pic) is no longer locked as it was before.


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How to get longest path instead of shortes path in geometry nodes?
Any idea how to resolve this topic longest path instead shortest?

I suspect the answer to this is you can't, unless you can constrain the problem further.

Yes I know stupid question It 'd go to the infinity. What I meant is to take longest path from 0 to height of Z axis.

Without loops this problem is not trivial to solve I'm afraid


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How to keep linear interpolation setting without uv map bleeding?
So I have a texture atlas with a uv map for tiles in my landscape. I know you can set interpolation as closest to stop the bleeding, but I dont like the look of my textures with closest interpolation on. Is there any way to keep it linear without the bleeding? The bleed is the white lines between each uv tile.

Hello and welcome. Can you share a screenshot that describes the issue?

I'm using a uv map to tile textures. but using linear interpolation gives me a white outline round each tile.

The usual solution is to add padding around the islands in the atlas: http://wiki.polycount.com/wiki/Edge_padding


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Cycles render is transparent/grey irrespective of material
just.... what is this please? Suddenly, even the basic Principled BSDF material looks like this in Cycles. Thanks! :)

Maybe it's a bug, is it the same with a previous version of Blender?

Yes, I thought that maybe downloading new version 3.5. today would help, but it didn't...

Looks like there are no lights in the scene.  Check if there are lights and if they are enabled for rendering (camera icon in the outliner). Make sure that they aren't in a closed/deactivated collection. Do use an HDRI in the World Properties (https://i.sstatic.net/4FM70.png)? The default color is dark grey. -- And yes, it could be a bug/limitation. When I use complex shaders, the integrated GPU on my laptop no longer can handle dynamic lights and just turns them off until I restart Blender. Does it also happen when you render with Cycles on the CPU?

Strangely enough, the solution was to take everything a copy it to a new blender file ✔. Thank you, guys, but I have still no clue what is happening...
And yes, I was attempting to render in Cycles, have never experienced any problem before

The issue is basically the material is hidden. Use Alt + H, but since you are using a Mac that will be Opt + H.

Can you explain this in more detail? How can a material be hidden? What do you have to select to reveal the hidden material?

Unfortunatelly, not the case apparently. :( But thanks for trying to help.


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How can I create an outline around an object?
I want to use a geometry node to place a fixed number of instances on the outline of an object based on the camera's viewpoint. How can I place a fixed number of points on the outline of an object that looks like this image based on the view? The image is an just example of manually placing vertices. I also tried the method using boolean, but I didn't get a satisfactory result. Any help would be greatly appreciated!

I was able to place the points on the outline using the normal and the camera, but I did not have control over the exact number and position.

Update 6/4
-I succeeded in creating an outline around the object and resampling it to add dots! However, the curve is a bit unstable, so the position of the vertex flickers. I'll try to find a way to make it more stable.
blend file : https://drive.google.com/file/d/1nutIUEuca_n9tiB0d8Tlq4dizP3qhIs9/view?usp=sharing

Have you already created the outline, or is this about the points AND the outline?

I want to place the points along an outline. The images are just manually placed vertices for illustrative purposes. Using normals and cameras, I was able to place the points on the outline, but I had no control over the exact location and number of points. I am trying to place the points on an outline as shown in this video. https://www.youtube.com/watch?v=bzGW4TDXE-0

Have you already tried the node Resample Curve?

I know about the Resample curve node, but I don't know how to use it to get the result I want. can you give me some advice?

I would love to do that if you can give me a curve to work with for that. But unfortunately, from my point of view, your example shown above does not generate the geometry needed for this, because no consistent outline is generated. So I think the real problem lies somewhere else. Therefore, the question should really be "How can I create an outline around an object?"

You are right! So how can I create an outline around the object? I've been searching so far, but haven't been able to find a clear solution. Currently the method that works best is using multiple grids and booleans.

Well, that's the big question (Which is not easy to answer, by the way). But I would suggest you change that question so that we can get closer to a possible answer. Because once you have created curves that represent an outline of an object, it is only a small step to a correct subdivision and conversion to points.

I get it! Changed question title. A few days ago I found Line Art Curve Modifier, a paid addon that uses geometry nodes. Lines not dots, but very similar to what I want. https://blendermarket.com/products/line-art-curve-modifer

I succeeded in creating an outline around the object and resampling it to add dots! However, the curve is a bit unstable, so the position of the vertex flickers. I'll try to find a way to make it more stable. Blend File : https://drive.google.com/file/d/1nutIUEuca_n9tiB0d8Tlq4dizP3qhIs9/view?usp=sharing

I don't know if I'll find the energy to try, so I'll just share an idea: spawn points as you already do, based on normals, but many more points. Then flatten the points to a single plane perpendicular to camera rays. Then you can spawn curves of 0 length on those points and fill the curve. Then delete internal edges (neighbors = 2). Now convert to curve and it's the outline?


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What is the difference between Doubling the value vs Doubling the Texture (Noise Texture Node)
Beginner here. Need help on understanding the difference between the below set up. Why is that blender give me two different finish when I do 'double value' vs 'double texture node'?
First image is having one noise texture node set up. Having the Scale at 34, Detail at 30 and Roughness at 1.

Second image is having two noise texture set up, the values were separated compared to that of the first image.

The results are different simply because your two examples are telling Blender to perform completely different things - the Noise Texture cannot be split in that way to produce the same result.
In your first example you’re using the input coordinates (effectively Generated coordinates) to generate noise at a scale of 34 and roughness of 1. In your second example you’re using the input coordinates (the same as in the first example) to produce noise at a different scale but then using the output of that (which then won’t relate to the original coordinates) at yet another scale (the Scale represents the scale of the texture in texture space, not the amount of noise as you seem to assume).
This second example is effectively producing noise that varies based on the amount of noise from the first Noise, rather than on the position in the texture.


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Shader for orthographic projection of the texture on the model
I recently started looking for a shader for orthographic projection of a texture onto a model from the camera. I needed to bake a projected texture. Found an example with perspective projection and OSL rays. However, I don't understand how to rewrite this for the orthographic case. I see in the code finding the camera normals, but next for me is shader magic. Could someone help to do this with the orthographic case?

Update:
Try to reproduce answer

I'm not sure to understand the bake you want to obtain. But why not simply : https://i.sstatic.net/gUxeD.jpg

@lemon could you upload the blender file?

Here you are, Denis,

@lemon https://ibb.co/d580wP1 - your case , https://ibb.co/XSCx9dy - goal. In your implementation, the texture is also drawn on those parts that are not visible from the camera. Is there a way to avoid this?

@lemon ... hope I haven't stepped on your toes.. will back out if you put in your own answer.

@RobinBetts, no pb at all. You're the Betts, you know ; )

Here's one way to bake an ortho projection from the camera

.. with the backfacing shading-points mixed to another colour:

Here, the mix is plugged straight into the Material Output, and 'Emission' is baked.
It's all a bit confusing while you're setting it up, because 'Camera Space' in your node tree includes the camera space of the viewports. That means you're working blind; you can't see round the back of your object until the bake is made and assigned.

I just tried to reproduce your solution. However, for some reason I got a darkened result. Could you please attach the file or look at the file that I will attach now when I change the question?

@denisbaic, try to adjust your bake settings... "diffuse" and only "color"

@lemon it worked! Thanks to both of you!

@denisbaic, please accept Robin's answer.

Hi, @denisbaic thanks! My mix was stuck straight into the material output without an explicit shader, because I didn't know how you wanted to use your texture, and I baked 'Emisson'. Same difference.. I should have included that in the illustration.


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How do you tweak the length of children hair's interpolation between parent gradually?
Blender 3.6

I'm trying to make a feather using hair particle but the hair length of children between the parent interpolates in an unpredictable manner.

I've read Unpredictable hair particles in shallow surface but it doesn't answer the question.
What I'm trying to achieve is to make the hair length of children between parent change gradually so that the curve is smooth and not bumpy. Is there a way to do so or are there any better solution?


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How to select faces around sharp edges and subdivide by using Geometry Nodes?
I am trying to test Geometry Nodes in Blender 3.5.
I have two different cylinders and apply union operation with Mesh Boolean node as follows:

The geometry nodes for this operation are as follows:

What I want to do is to select faces around sharp edges including the juncture of the two cylinders and apply subdivision to get more faces around sharp edges.
I tried to figure out what kind of node do the work but in vain.
Is it not possible yet in Blender 3.5 to do what I am trying to do?

if you provide blend file you would attract more lazy people (like me) to help you because we don't have to recreate everything on our own

You should look into the "Intersecting Edges" output of the Mesh Boolean node

@Chris How can I upload blend file. I could not see upload button for blend file.

@Chris I uploaded a blend file.

you can do it like this...but (!) it doesn't make a nice topology which i think you wanna have...

Hint:
this works only, if you change the settings of one cylinder like this:

the separated geometry (from intersecting) looks like this:

or like this if you increase the threshold:

I have no clue whether it is a bug, if the vertices and edges overlap exactly in mesh boolean...because the result of the intersecting edges is just nothing.

Thank you so much. As you said, it would be better if the refined topology develops in a concentric way, though. Anyway I can now figure out a little how Geometry Nodes work. It's somewhat odd it works only when cylinder segment size is something other than 32 and 12. Is it kind of bug?

i assume, but i am not sure.


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The y-axis behaves strangely
For some reason the Y-axis is behaving strangely. If I press NumPad 1 it gives me the -Y view  and CtrlNumPad 1 gives me the +Y view .
If I activate the mirror on X it gives me a mirror on Y:

I reset Blender, uninstalled it and reinstalled it. Same thing. I think it's a problem with Windows 10.

It's arbitrary
Why do objects in front and back view look reversed?
It's an arbitrary decision (other than complying to the industry standard) for -Y to be front view, and +Y to be back view. It may be surprising and perceived as inconsistent to those who intuitively think front view is preferred to back (usually we look at things from the front), and so just like with top/bottom, the "preferred" option should have a plus sign (I guess the logic would be you then don't have to use the implied sign every time you describe the more common perspective)

As for the mirroring - You choose the coordinate component to be flipped. On the screenshot the shape has all it's vertices copied with same coordinates except X is flipped. Keep in mind there's no Y plane, you would have to specify if you mean YX or YZ plane.
So if your setup was indeed mirroring on the Y axis, then the mirrored object should have a narrow part on the bottom, unlike what is seen with the mirror modifier set to X:

this answer as i remember was the second one

@hamed.design just below the question you can choose how to sort the answers: https://i.imgur.com/sliEg7K.png

As far as I know, there is no 'industry standard', not even defacto for this.  Variations are common enough that some CAD software, such as solidworks, actually make it an option to choose whether front is positive or negative Y axis view

It's true , the mirror on X axis is actually X plane , if you want to understand this when you're pressing  G and moving an object try to use ⇧ Shift +  Z , it will only move your objects  toward Z plane not Z axis , also you can try ⇧ Shift +  X to move your object in X plane.

Thank you for your reply. I'm quite new to Blender but if I understand correctly if I press numpad 1 I should end up on the Y view not -Y.

@Yaumes That's true already  , almost all of 3d modeling softwares are doing this and it's pretty standard .

Thanks for your answers. You seem to be right :o)

There is no X, Y or Z planes. Shift + Z locks Z component of the coordinates, you can move toward Z axis or away from it in that mode, but I fail to see how it's helpful here.

@MarkusvonBroady seriously ? you even mentioned that in your answer as YX plane !!! , ok Z plane is the one visible when you're viewing the scene from perspective view all the time (Grid) , z plane is a plane that the normal direction is on z axis , and this is a very design standard rule across all modeling softwares , and if with blender they didn't meant to Z plane , then why we won't press XY , instead of Shift + Z ? I just updated my answer just see the screenshot and upgrade your knowledge .

I googled and indeed there is Z plane, but it refers to a complex plane or a Z-transform in signal processing...? Not my area of expertise but I think it's unrelated. I figured by now what you mean by X plane is where X = 0. That makes it correct, though you're explaining concept A with concept B, where I'd assume both to be unknown to the OP, and still, the statement about locking "move your objects toward Z plane" is still wrong in your answer.

@yaumes if you find this answer true and understandable please accept this answer by hitting the correct sign on the left side of this answer .

This answer from a different stack exchange explains the convention for naming X, Y, and Z planes.  The foo-plane is the plane perpendicular to the foo axis  that contains the two non-foo axis.

NOTE: In geometry it is more common to use the two non-foo axis to name the plane rather than foo, so the 'Y' plane in gaming is usually the XZ plane in geometry, et cetera.

@MartyFouts true explanation , if we are naming our self a designer , we must know some design standard principles , its a very simple thing , because we can't make a plane with one axis , when we are naming a plane with one axis we mean a plane with normal toward that axis , its not neede to be that smart to understood . Sorry for bad eng .


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Caps on Curve (Geometry Nodes) not included in my Shader / Capture Attribute complete Geometry
Sorry for the newbie question:
I need rounded Caps on curves using Geometry Nodes. So I followed various tutorials and ended up combining elements from these two https://www.youtube.com/watch?v=EV9qgvz7yRU and https://www.youtube.com/watch?v=dC4YrxYhJzU
Now, I've created a shader with a gradient that follows along the objects, following this tutorial: https://www.youtube.com/watch?v=XDKlfxmnnIQ). It works fine, but the rounded caps don't seem to be integrated into the object. Which – to my limited knowledge – is logical, as the "Capture Attribute" Node gets its "Geometry" Information from "Group Input"; which does net yet contain the caps. But I cant figure out how the change this.

Any suggestions how to get my shader to include the rounded caps? Thanks you!
EDIT: I've uploaded the blend file:

It might be helpful to people trying to help you if you uploaded an example blend file to the site https://blend-exchange.com and add that link in the question.

I didn't click on the links provided, but it is one of very suboptimal Youtube tutorial for caps, that inspired me to write my own (much better of course) solution: https://blender.stackexchange.com/a/294496/60486

Thanks! I've uploaded the blend file. I'm aware that there are better solutions for caps. I've seen so many tutorials. Crazy that there isn't an easy option for this in Blender. Good link to get an idea for a different approach.
But the main question would be, how to include the caps in my shader.

i will never understand why people are watching yt videos without voice who explain what they are doing (and additional with annoying music). There are so much better video tutorials out there e.g. from Erindale or Johnny Matthews. With the exception if you really don't find tutorials with voice...but normally you will find one.

True. That's why i had to use two tutorials. The one w/o voice also is vertical and you can't see what they are doing. Thanks for your recommendations.
But I included the YT videos to explain my setup. The real questions is about the use of the "Capture Attribute" node and how I can include the entire object, so my shader (with a gradient following the curve) also works on the rounded caps.


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How to inject material instance for specific objects?
I am creating an addon that allows you to create multiple shader based section planes. It was quite easy when I dealt with it on per material basis. Now I'm trying to do per Object basis. Now each section plane has its own list of objects that it affects. This creates two problems:

One is that I need to break instancing and create a single user material so that other objects with the same material are not affected. This is undesirable for me as I want the user to still be able to change the material globally and not manually for each new material

The second is keeping track of the materials. Each section plane can have multiple objects which means I cannot have only two material instances (one with and one without my node group). This can create a real mess in larger scene as I need to create a new single user material for each material within the object (because some contain only one node group, some none and some more)

For illustration:

These two section planes should affect each their own group of objects. local_1 should affect pinkBox object and local_2 should affect greenBox & pinkBox objects. There is also third object in the scene called pinkSphere that is not affected by any section plane but uses the same material instance as pinkBox.

This is what the material should behave like for pinkBox. Notice that I still want to keep the instance of 'pinkMat' and just inject the two node group at the end.

This is what it should behave like for pinkSphere which is not affected by any section plane.
I am looking for an easy way out of this. Basically what I need is to take whatever flows into the material output node, run it through my node groups and send it back to the material output. This way the instancing would not be broken and I wouldn't have to worry about tracking the materials. Is there any way to do injection like this? If not can you advise me the best way to do this without completely overflowing the blender file with unnecessary materials?

Could you please add some illustration of that? Injecting some group, node tree part, in another one is possible, though, hard to have a good idea of what you want without some example(s).

I updated the post with some screenshots. Hopefully it'll be clearer what I try to achieve

If the material that the user should be still able to modify is not itself a node group (and the user should know that), I don't see how this could be possible.


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How can I spread an object only on horizontal parts of surface using geometry nodes
I have some stylized hills created with geometry nodes (by attribute sample texture) now I need to scatter some spheres only on horizontal parts of the hills. How can I do that?

I would check the normals.

You can use the Density input of the Point Distribute node to test against the local normal. If the normal's Z component is 1, the face is horizontal, facing straight up. If it's lower than 1, there is a slope. The closer it is to 0, the closer it is to vertical. It can also be negative but in the case of regular hills this should not happen.
In the end we have 2 inputs :

Factor : At which angle the objects will start spawning
Density

Possible improvements :

Change the Factor input to be a maximal angle instead, using some simple trigonometry :

Use a gradient falloff instead of 0 or 1 values when the criterion is met. Using the Attribute Map Range we can setup gradients.

your attribute separate node really made me nervous..... Great solution!

what? WWII ? where? don't understand. No, i meant the cut text in your first pic - result - result y - result - i thought you had a custom node on my first view but the node width was just too small, so it cut x and z, but not y ;) looks weird ;)

@Chris Oh, right, didn't notice it, it sure looks weird :p

Really...i the first second i thought: OMG, Gorgious is a genius. He made custom nodes for geometry nodes.... :)

@Gorgious has said it all.. but this is a very slight variation, (made at the same time)

Adjust Minimum of Map Range, for threshold steepness, (or other fields, for distribution according to steepness)
Adjust B float of Multiply for density.

niiiiiiiiiiiiiiiice!!!!

@Chris Gorgious has covered it much better, though, IMO. His should be the accepted answer. We could knock out the multiplier, too, and use the one in the distribute node.

Looks like the user doesn't often accept answer

Note: The nodes in the solution(s) above have been replaced in newer versions of Blender. I'm still trying to figure out the replacements.


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UV unwrapping a milk/juice carton box
I have a milk carton which I have modeled and my attempt at UV unwrapping it:

However, the UV unwrap wasn't too successful as there are some mismatches.
What projection should I use for UV unwrapping this object? Are there any settings or other considerations I should be thinking about when UV unwrapping such an object?
Here is the blender file if you'd like to investigate:

Here are what my seams look like. There appears to be a lot of them because the edges are beveled:

It's a box made of flat plastic sheet... I would suggest modelling it as it is in reality and marking the seams where they are in reality. After that pretty much all you have to do is hit u key twice.

When marking edges as seams. Should I mark all the beveled edges? Or just the 'middle' one? I have attached a screenshot for reference.

I would suggest you take a carton of milk(physically to your hands, because why not, you probably have it...) and having a look at where the seams are. There is usually only one seam on the side, because it's a single flat sheet folded so mark that seam.

I hesitate to give an answer to this question, because this is the most basic case of the most standard UV unwrapping process in Blender. You just mark seams, and unwrap, that's it. This is covered by absolutely any basic UV unwrapping tutorial thousands of times way better than I could write in an answer. Check the docs and watch some tutorials.  This maybe...

version 2D to 3D
Milk box is based on a one peace of sheet (plane) ...

... so the proper way could be to model this (or any other similar template) as 2D and use a rig to pack into a 3D shape (like here with one of my favourite addon useful for packing design).

This way is a bit harder since this simple topology is not considering paper thickness. It means - faces at the same location will overlap each other (z-fight appearance). In this case it seems Solidify modifier eliminated this issue (thanks to extrusion in face normal direction, but proper way should be to create a topology considering the paper thickness, but it is anther story.

So, here is another option ...
version 3D from Cube
Or for simplicity now create the model from a Cube ... delete upper face, Extrude, Subdivide top-side edges, reposition vertices ...

One vertical edge and three bottom edges Mark as Seams (to let blender know where to split UVmap). Select one face, than all and Unwrap > Folow Active Quad.
To Bevel edges don't use it before you have basic UVmap.
Do it after or use Bevel modifier and Solidify modifier.

This example is just a quick sketch. I didn't follow any measurements.


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Geo Nodes: generate non-intersecting paths like on a circuit board
I want to make a circuit board out of a plane, and it has to be procedural too. I'm looking into a solution that spawns paths from a square, which make seemingly random 45° or 90° turns and yet don't intersect.

please add a picture, screenshot of what you like to have. There might be some non-pilots in here....

There, I added it

i am not sure whether geometry nodes is "the easiest" solution here. Might be better to use sverchok or animation nodes...

i know, right? But I just wanna explore the breaking point of geo nodes. This is more like an experiment to see how much can be achieved with geo nodes.

I guess this is more like an experiment - I agree with you on that, so this question is not really asking for a proper solution to a specific problem. It's more like asking for brainstorming and trying out something...

I think a more focused, and so valid question would be: How to spawn curves from external dots (dots on edge) of a 2D array of dots, that move outwards, don't intersect and make random 45°/90° turns.

@MarkusvonBroady EXACTLY! You hit the nail RIGHT on the head! Spawning isn't a difficult issue. What really makes my head turn is how to keep them from intersecting each other.

You need some kind of sequential algorithm I think, and until we have loops in GN it's going to be really hard. But it's coming in one of the future release !


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How to make Saturn ring bigger (or any torus)
Is possible to make Saturn ring bigger
Screenshot

I wanted to make the ring bigger

if you want to make it thicker, switch to Edit mode, select all, press Alt S and drag

@moonboots what is edit mode?

it's the mode where you can change the mesh, select the ring and press Tab

yeah, but alt-s and tab to change to edit mode are 3 (THREEEEEEE) keystrokes. Task was : with the fewest keystrokes....!! Moonboots: sorry, i have no picture for you. And also no recall for you....so sorrrrrrry!!!!

@Chris nvm, don't delete your answer

@Chris well in that case, call Chris, he's going to python you the thickenyourtorus addon

Select the torus, press S and move your mouse.

I don't have any mouse in my house. Does it work with a cat?

@moonboots really?

actually, yes, my parents have some, but they trap them

@moonboots they trap mice or cats?

@MarkusvonBroady you get a cat ass trophy if you trap enough cats.

@moonboots must you always treat Chris like this!?!?! LOL

@james_t Chris is my challenger, I need to destroy him!!!!

@Markus von Broady they trap mice unfortunately   :/  (true story)

If we define:
$O$ - origin
$A$ - a vertex laying on the X axis, with the smallest positive X value
$B$ - a vertex laying on the X axis, with the largest positive X value
$I$ - a point exactly halfway between A and B

To change the torus'es major radius $|OI|$, without changing the torus'es minor radius $|IA| = |IB|$:

Enable Edit Mesh Tools add-on.
In Edit Mode select both $A$ and $B$ vertices, F to create an edge connecting them.
In N Numbers Panel, Edit tab, click on Edge Tools > Set Edge Length.
Hover your digital mouse over Target Length field, CtrlC to copy the value, click outside the popup window to avoid resizing.
A Select All, S scale however you want (within reason).
Select only the edge created in p. 1.
Repeat p. 2.
Click on the Target Length field, Home, CtrlV, -, Enter (calculating the difference).
Repeat p. 3.
Remove the edge created in p. 1.
A Select All, AltS to Starve/Feed, click.
In the popup, click on the Offset field, CtrlV, /, 2, Enter.

I fear it's not as simple as Chris'es solution.

I don't understand. But I will test this later

I would always use this solution, the answer from @Chris is so mundane. By the way, do you have a digital cat as well?

What is "Enable Edit Mesh Tools add-on."

@Fmbalbuena Edit > Preferences... Add-ons


text:
Geo Nodes: fill a volume with random-sized cubes
does anyone know how to turn any object into random sized cubes?
Example:
I'm not the best with geo-nodes but I have an idea about how to do it but I need some guidance.
I Think I'll need to use instances on points and random scale but I don't know how to fully do it.

For same-sized cubes, you'd probably use the Remesh modifier.

I can see on the reference, the cuboids overlap:

This makes the effect very easy to achieve:

thanks, that's exactly what I meant I missed some nodes and you added them.

This can also be solved with non-overlapping random-scale cubes.
P.s. "non-overlapping" = axis-oriented integer-style

Nice, they clearly are overlapping, though :P

cool concept but they are indeed overlapping

@JoxXx What else did you expect? Either this way or "honest" blocks – the amount of geometry will not change much. And removing internal or overlapping geometry would take unnecessarily heavy calculations.

It's a nice effect, I was just making sure people don't get unnecessarily confused. A non-overlapping method could be possible, using a simulation zone maybe (but if it's supposed to be animated, with the deforming base, then that's a problem). One more idea: fill the volume with points (base for instancing cubes), but then merge some points at random on one axis (e.g. $z$, could be allowed by temp. scaling the point cloud), mark which points were merged to replace them with vertical cuboids, maybe repeat the process, spawn cuboids, scale each cuboid down on a single, random axis…


text:
Distribute circles evenly along a curve
I need the circles to appear from the center with a gap equal to one circle and at the end gather towards each other
 Here the circles came out from the center one by one with distance from each other
 And then they reached the end and in turn began to lean against each other

And what did u try so far?

This version assumes you want to make your instances appear at one end of the curve, move along it at fixed intervals, and accumulate at the other end:
This GN group modifies the curve, and distributes Count instances along it, with a given Gap between them, at a given Offset. Animating the Offset will move the instances along the curve.

It samples the input curve at (reversed-instance-index * gap) + offset length, retrieving that position, at which to locate the instances. Left to itself, that would clump the instances at the endpoints of the curve, so two adjustments are made:

The sample-length is clamped for each instance at (curve-length - instance-index * instance-width)
If the offset sampled  length is 0 or less, the instances are deleted.

Thanks a lot! Exactly what is needed!

It looks pretty straight-forward, divide the length of the curve by the number of circles:

If you need to adjust the circle size so the circles touch, just set the circle diameter to the obtained segment length (the node has radius input, which is half of a diameter so I divide by 2):

Geometry Nodes

Images above.  Left side image to meet original question goals.  Right side image with a random exploration of geometry nodes with a reversed last to first gif adventure.

Above image. Geometry modifier values.  Like all geometry modifiers, changing the values in the modifiers can give various results.  The results need not be limited to the original question.  Limited value testing.  Please inspect and modify to suit your tastes on your computer.

First two count values should be the same.  Number of circular meshes to appear
Item 03. Frame. When the mesh should appear on curve. Items are more distant on curve to meet original question goals.
Item 04. Frame. When transition should appear.  Items can be spaced closer after this frame as time increases, to meet original question goals.
Item 05. End Frame.  When items are closest end of curve potentially, to meet original question goals.
Item 06-09. Curve Trim values. Begin and End values. Range of curve occupation. Value in the range [0.0,1.0].  Range 1 < Range 2 to meet original question goals.

Image above.  Thumbnail in upper left is guide.

Image above.  Nodes for group or function.


text:
How to raise multiple edges with linear falloff ending exactly on a particular edge
I'm starting from here:

And I want to get there:

There must be an easy way to do it but I can't find it...
I dissolved the two middle edges and the four under to make a big brick. Then I moved the side edge up. Then I made the cut again using ✲ CtrlR on the top face. To finally join the vertices vertically.
I tried proportional editing but it selected way more vertices than I wanted.
I tried to move the side edge first then align the vertices somehow but that was tricky.
Is there an easy way to do it?

Why overcomplicate? Just select the left most edge then press G Z 3 then select the 2nd edge and G Z 2 and then select 3rd edge G Z 1 or any other linear values instead of 3,2,1.

@HarryMcKenzie I imagine sometimes he will have e.g. 32 edge loops to modify this way. The duplicate is very reasonable at least if you don't have multiple slopes in parallel.

@MarkusvonBroady oh yeah didnt think about that haha. wait how did you add an answer? I thought this was closed  40 min ago XD

@HarryMcKenzie I have secret admin privileges don't tell anyone.

@MarkusvonBroady reported~! XD

Hi, Thanks for your answers. So the best way is proportional editing with hide.. I hoped for something easier like based on the active edge.
The main issue i have with the other aligning solutions (including setting Z value manually) is that i can't estimate how it will sort out and have to test until it looks good. My way allowed me to move the vertices and adjust the Z value on the fly. Also thx for the precision test, very interesting even if i don't know python yet!

OK, since previous revision was too complicated :D

Hide geometry you don't want to move except the one nearest vertex to the element you will be moving directly.
Click on the vertex you intend to move directly, then ⬆ Shift+click on the one vertex you don't want to move.
⬆ ShiftF4 to switch to Python console and paste the following:

import bmesh;h=bmesh.from_edit_mesh(C.object.data).select_history;C.scene.tool_settings.proportional_distance=(h[0].co-h[1].co).length;C.area.type='VIEW_3D';

↩ Enter to return to 3D viewport
Now you can move the chosen element and the Proportional Size should be just right.

@GordonBrinkmann define "accurate", if you start with uneven coordinates as you usually do, there's really no difference in the last example. And it's not that complicated too, it's just 4 different approaches packed to one.


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Can't find point instance
I'm following a tutorial (4:57 time stamp) where the person gets point instances and in Blender 3.0 its gone.
How do I get the same effect in Blender 3.0 now that it has changed completely?

Probably like this:
You will just use whatever you want instead of that Cube node

If you want to use object in your scene, like in tutorial:

thank you so much, you saved the day..  have a great one mate!


text:
Disconnect vertices to open a book-like object (ripping edges)
I'm designing a typical video game DVD box.
I have done the separation of edges but how can I do the physical separation of the opening?
This is what I have right now in edit mode

I use Blender 2.8
Many Thanks.

It is not clear what you mean by 'microcut'.

I mean to make the small gap that exists where the box separates when you open it.

Select half of the geometry, Y key to split. Then you can select the rear edge, choose active element as transform pivot point, rotate around Z axis by very small amount.

@MarkusvonBroady many thanks

As already hinted by Marty's edit, you can select all vertices except those meant to stay connected and press V to Rip Vertices:

If you find ripping unintuitive (it depends on mouse cursor position), you can also select half of the geometry and press Y to Split Selection:

You may want to merge some vertices afterwards to have exactly the same effect as ripping...

Finally, if you want the separation to be directly visible, you may want to select something from the connected geometry (the one not ripped on first GIF, or merged on the previous GIF) and rotate around Z axis on XY coordinates of that geometry by changing  Transform Pivot Point to  Active Element (shortcut ., A, then RZ)


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Select the faces on top with python
I'm trying to use the circle select to select only the faces on top of a mesh. But i got RuntimeError: Operator bpy.ops.view3d.select_circle.poll() expected a view3d region. How can i set the view3d region? Or is there a better way to select only the top faces? PS: The actual mesh would be procedurally generated.

def select_faces(obj):
    context = bpy.context
    context.view_layer.objects.active = context.scene.objects[obj]
    if context.object.mode != 'EDIT':
        bpy.ops.object.mode_set(mode='EDIT')

    context.area.type = 'VIEW_3D'
    bpy.ops.view3d.view_axis(type='TOP')
    bpy.ops.view3d.select_circle(radius=100,mode='ADD')

select_faces('Plane')

Your code should be like this
 def select_faces(obj):
    context = bpy.context
    context.view_layer.objects.active = context.scene.objects[obj]
    if context.object.mode != 'EDIT':
        bpy.ops.object.mode_set(mode='EDIT')

    context.area.type = 'VIEW_3D'
    if bpy.ops.view3d.view_axis.poll():
       bpy.ops.view3d.view_axis(type='TOP')
       bpy.ops.view3d.select_circle(radius=100,mode='ADD')

  select_faces('Plane')


text:
How to model a spherical snowflake?

Hello everyone, I've been trying to model this shape in blender, I tried bending planes, projecting curves on the surfaces but still couldn't get the perfect result.
Is it possible to  project this snow flakes texture on a sphere & convert it into curves or mesh ?
Thanks !

What do you mean by "project this snowflake texture on a sphere" ? Do you have an image texture of that snowflake ? How did you get this model ?

The following workflow is non-destructive, meaning you can tweak basically anything anytime. It may not be optimal but that's how I would do it.
There are multiple ways of achieving that. Especially the mapping part, other mapping could be better than mine.
You can model the smallest possible part of the snowflake, then array it and map it to a sphere. Anything else is purely that same part (almost like a fractal). In your case the only thing to model is this green part :

Modeling of the pattern
Let's build half of a branch of the snowflake. Then add mirror modifier, and a bunch of array to have a pattern large enough.

Array #1 with Object Offset, create an empty and rotate it 60°
Array #2 with Relative or Constant Offset (doesn't matter much) to create on diagonal of flakes
Array #3 with Relative or Constant Offset to repeat that diagonal horizontally

Feel free to extend as much as needed (see next step).
Map geometry from plane to sphere (Geometry Nodes)
I won't go into much detail here. It's basically math, how you map the initial x and z coordinates to a spherical set of coordinates. Long story short :

I start with a vector (1,0,0)
Rotate it along y-axis (based on initial z-axis)
Rotate it along z-axis (based on initial x-axis).

Here are the geometry nodes I created :

And the result here :

Then it's only a matter of tweaking the multiple Map Range so that everything align correctly (I didn't tweak anything so don't follow my steps too closely).

Here is a classical approach, first create the pattern (standing on Z, as it is very symmetrical you can use some Mirror modifiers en X and Z):

Array it on X:

Give it a Simple Deform modifier, Bend mode, 180° on X:

And a Simple Deform modifier, Bend mode, 360° on Z:

Thank you this method is really helpful

Please mark moonboots answer as solution if it solved your question.

Or mark Lutzi's solution if this is the one you chose  ;)


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How to create a Sequin Sign?
Beginner here interested in recreating this sign. Would I just apply a physics collision modifier to a bunch of squares and use the wind force field to recreate the flickering effect of the sequins?

Reference - anim GIF

I don't know if this will work for you, but give it a try. Make 2 planes - Subdivide one by 30 or so, and scale the other down (I scaled by 0.1, then 0.25 again to make it "small enough" - you will be able to tell if there's any overlap in the next step)

Add a Geometry Nodes Modifier to the large plane, and instance the smaller plane at each of its vertices by using the node setup below. For the Attribute Randomize Node, set the Attribute to Rotation to affect the rotation of each individual instance.

To animate the "wall of squares", add a Value Node set to #frame (just type it in the box) and maybe use a math node (Multiply by 0.5 or so) to slow things down. Connect this to the Seed input of the Attribute Randomize:

The movement is a bit choppy (due to only changing the seed value), however it still seems to replicate the video convincingly. If needed , there are further steps that can be taken to restrict the rotation of the squares to the X-axis.


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Keying node removing everything but the green screen
I'm just learning how to green screen. I started in Movie Clip Editor, opened a clip, added a Mask, and then switched to the Compositing tab, and added the nodes shown in the pictures.
This was all according to a tutorial. And in the tutorial the green screen disappeared. However, for me only the green screen remains. Not sure what I'm doing wrong?

I readded the nodes in a different order and it worked.

I readded the nodes in a different order and it worked.
I don't remember what order made it not work. But to make it work I added nodes in this order:

Movie Clip
Keying (and set the Key color)
Connect 1 to 2
Mask
Color Invert
Connect 3 to 4 to 5

(Note that both setups are the same as in the image in the question, only the order of adding was different)

I could not get this to work.  The Mask node has no input, so how can 3 connect to 4?

Try removing the "Color invert node"

The color invert node just inverts the mask, so that the area I'm interested in gets selected rather than the background

To tackle that, connect the "Matte" in the "Keying Node" to "Alpha" in the "Viewer node"

Hmm, that didn't have any effect. In any case, I readded the nodes in a different order, and now it's working. Thank you for your time and effort

Alright. Since the problem has been solved, please mark it as Solved

This node setup works (just ignore the brightness & gamma nodes shown here).  I used "color key" node", but it's the same principle for the "keying node".

The original image goes int the "key" node
The "key" matte goes into the "color ramp" node

Note the the ramp is inverted with white on the left.  That inverts the key to show only the selected color.

The "color ramp" goes into the factor of the "alpha over" node

The original image goes into the bottom slot of "alpha over"
The background images goes into the top image slot of "alpha over".  In the example, I left the top slot empty.


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Game engine lights not pointing to same place as in a render
I'm working on an auditorium scene for my game. I set all the lights up and did a quick model of the mesh, and rendered it. It came out all right, but when I went into the game engine and started it, only two or three of the lights actually pointed to where I wanted it. Why?
Blend file at pasteall.org
Blender Internal:

Game Engine:

Try using GLSL shading instead of multitexture.

Multitexture shading shades the mesh per vertex. Since your object doesn't have many vertices where the lights should be illuminating, the results are misleading.
If you subdivide your mesh a lot, multitexture gives a more predictable result, but not as nice as GLSL:

This worked! I also had to set my view-port shading to Texture for this to work, which caught me for a second. Do you mind explaining why multi-texture gave me such funky results?

@KevinJohnson Yes, the game engine uses the viewport shading setting (to some extent). I updated my answer.

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


text:
Mixing Displacement Procedural Texture
Is there a way to mix procedural textures (like clouds, voronio, etc) for the Displace modifier?
I managed to work with nodes (like in cycles) to produce a mix using the Brush tab in Node editor and it does actually show a preview when selecting it in the Textures tab in Properties editor, but has no effect in the modifier.
Thanks

You can do this with newest Blender versions (as I remember from 2.78 and up).

First of all you'll need to turn on Experimental features (1) and select under Material tab Displacement as True (2). You can use Both but mixing Displacement with Bump gives weird results. Next step is to add Subdivision Surface modifier with Adaptive checked.
You can check whole tutorial about it here: Introduction to Microdisplacements


text:
How to reduce artifacts on curved text/vector
this is a problem I face a lot when working with branding and typography.
After importing vectors/typing, extruding and bending (simple deform or curve modifiers) it always come up with those ugly polygon artifacts:

Now, I know the cause of this is that the front faces of the text do not have the right topology nor enough polys to bend.
So, is there a good workflow to get rid of this without taking a huge load of time to retopo by hand or using the remesh modifier to an absurd high poly count?
Thanks

Please upload a blend file so that we can mess around with different possibilities before writing a guessed answer that might work. My first guess would be to use Remesh and Decimate modifiers.

Is the object a curve or was it converted to mesh?

Text (or curve based) objects are not meant to be curved in that direction, their inadequate topology will make their triangulated nature show. Make a mesh with proper topology before bending

@piegames this is not a problem with a specific case, its very easy to reproduce with any text or vector object

@fabriced It really doesn't matter, same results

@DuarteFarrajotaRamos yeah, I'm aware of that. Maybe I was not being very clear, I am looking for a fast workflow on this matter (that doesn't require to manually retopo the text)

Does this answer your question? Curve Object Deformed by Curve - Distortions (Artefacts)

I added a text, converted it to a mesh and extruded it 1 upwards. To get artifacts, I used a wave modifier. Yay, artifacts:

The artifact are because of the terrible topology Blender creates of the font. Usually, if the topology is too horrible for manual fixing, add a Remesh modifier and hope the best:

The Remesh modifier needs to be before the artifact-creating deformation. If you have to many vertices at the end, adding a Decimate modifier in Collapse mode works well.

Can you expand and/or give a .blend example? Usually with me Remesh makes most of the mesh disappear

Have you unchecked "Remove disconnected pieces"? I got this problem too but forgot to mention this option in the answer.

wow thanks I had never been able to work that modifier until your comment! Thanks so much!

Edit mode > Face > Beautify Faces worked!

What about deleting all front and back faces (select them quickly with C shortcut), selecting the remaining edge loop and fill with F?
Alternatively select the edge loops (Alt + Click) of each letter's front edge loop, duplicate it (Shift + D), make object (P), fill (F), then get the thickness back with a Solidify modifier.
Hope this helps


text:
How do I model a bottle case like this?
So, I'm not that new to blender or 3d modeling at all, but I've been cracking my head on this one.
I need to create a high resolution 3d model with a clean geometry of the following object:

This is a bottle case (used to keep beer cold on hot days).
I've tried many different methods, but I always end up with weird geometry and subsurf gives me weird results (too much sharpness on some places or weird artifacts).
I know this is a rather simple piece, but I think I'm working too much and my brain has just shut down :P
Thank you for your time!

...... Get a cylinder. Get some other cylinders. Use the other cylinders to Boolean the original cylinder. Ta data, you got this object.

@Bradman175 As far as this is tutorial request and not too good question you shouldn't answer with clearly wrong answer. "high resolution 3d model with a clean geometry" - you can't do this with Boolen.

@LukeD break the high resolution object into pieces? And then Boolean?

@LukeD - he's not so wrong after all. The object itself can be easily broken down into primitives and that's always the best way to start from. You then go from low-poly to high-poly by adding loopcuts (for the edges and of course to get an evenly subdivided object) and use a subdiv or multi-res modifier on top of it.

@metaphor_set and you call it "clean"? After Boolen? Ngons, tris, it's total mess not clean.

@Bradman175 Please make an answer with your method, I'm really curious about this "clean" geometry after boolen. Maybe I'll start using it.

@LukeD - I've done a lot more complicated stuff with boolean. No tris, no ngons - so yeah, I call it clean. If you are working with primitives it all comes down to proper planing, like "having the loop cuts at the right places" and such.

@metaphor_set I'm waiting for an answer then, it's always something new to learn.

@LukeD - it's basic stuff. Nothing new to learn here. You can also do it easily by yourself. Like I said, loopcuts at the right places, then you can either use boolean or just slide the vertices. That's all.

@metaphor_set we shouldn't talk in comments. Just make simple answer. I don't use boolen at all, so this case presented by OP is very interesting for me.

I have to return home to try this. It will take a while.

I really can't see why my question has been downvoted. it's clearly not that trivial or straightforward to produce this object (as you can see in the argument this caused in this comment section). if it's that simple/tutorial-like and not worthy of questioning, I would really appreciate if some of those guys would pm me the solution.
btw, boolean method gives terribly awful results after subdividing/beveling

After much fiddling around, I came to an acceptable solution, as follows:

1) Start with a cylinder

2) Use Inset and delete to poke a hole in the top-most face

3) Using the Knife tool, make two cuts conecting the vertices

4) Add edge loops in the center (ctrl+R + scroll)

5) Using proportional editing in Project 2d and Sphere shape (important!) drag the middle vertices down (use f6 to fine tune the proportional size and translation)

6) Add loops to the side of the tris (to avoid problems when subdividing)

7) Finish as needed. Here I used Solidify, Bevel and Subdiv modifiers. Also made a hole in the middle for that crease and use the Bevel tool to better define some edges (like in the flat segments in the top)
Now, I know this seems easy to many, but it really took me a while to realize I could use the Project 2d mode in proportional editing and to correctly cut and model's the top part this way.
I hope this helps somebody with similar problems.
ps: sorry for the crappy answer, I'm really not used to give this kind of answer nor I do have the recording tools for that.


text:
Action Animate Visibility in BGE
Is it possible to animate a given object's visibility inside an Action in Blender Game Engine?
I've been trying to make it by animating the "Invisible" button in the physics tab (it enables the Restrict Render property in the Dopesheet). Every other animation plays as it should within it's Action, but the visibility won't.

The "Restrict Render" setting only applies to the Cycles or BI renderer, but not the OpenGL renderer (used in the viewport, and for the Game Engine).
If you want to achieve something similar, animate the "Visible" attribute instead.

Note that this is a binary state. There's no way to fade, or gradually shift from visible to invisible. It will be totally visible one frame, and totally invisible the next frame.
If you're wanting to fade, you'll need to animate the Alpha channel instead (though there is some benefit to turning "Visibility" off, once something is totally transparent).

still, no good. animating the visibility in viewport yield the same results :/

Static

material option (Material tab/Game Settings Panel/Invisible flag)
physics option (Physics tab/Physics panel/Invisible button)

Dynamic

Visibility Actuator

Semi-transparency
(inefficient on invisible or opaque objects)

needs texture
needs material with

Material/Game Settings/Alpha Blend: Alpha Blend or Alpha Sort
Material/Transparency: enabled
Material/Transparency/Z-Transparency
Material/Transparency/Alpha: 0.0 .. 1.0 (can be keyframed)

coincidentally, the object I was trying to animate already had had transparency and alpha texture (kind of a hologram) which make the Material solution very messy (still haven't figured out how to handle it).

still, my current workaround is scaling the object down to 0 in all axis and bringing up to 1 in the following frame (to avoid interpolation)

Fading: http://blenderartists.org/forum/showthread.php?261926; Have you tried the visibility actuator?

the problem is that i need to animate the visibility in a given part in the middle of an action (like, i need to make it visible at around frame 10 of the action)

So it is part of an "atomic animation", or is it part of a sequence (e.g. move + turn + hide + move + show + turn)

it's a sequence. I could upload the file if it helps, but I couldn't find a way to do it in stackexchange.

This might help: https://blender.stackexchange.com/questions/50732/how-to-start-second-action-after-check-that-first-one-is-done-in-bge - it would allow you to play an action -> hide -> delay -> show -> play another action ...

authors: вика кутукова


text:
Blender 2.80+ Game Engine Replacement with Python
I was mostly using Blender for simulations and interactive visualizations controlled by Python. Now 2.80 REMOVED the Blender Game Engine with no replacement!!!!
Really not cool to remove something that was there for decades with no replacement! I have checked the external game engines but this is not the same - I need to export/import and write in some funny languages while I had everything at hand in Blender :-(
Blender became just a 3D modelling tool :-(
Is there any way so I can perform a live real-time visualizations that are Python controlled in new Blender 2.80+ ? I don't really need physics (but the collisions would be nice to have).
Any hints welcome.. or I need to stick to 2.79.

I think BGE was removed because nobody was maintaining it and other game engines were more accessible with better features.  Other engines do support python (UE4, Panda3D etc.) but will have a different API, which will have a small learning curve.  You can always get older versions of blender, what sort of interaction do you need?

so far i am trying to build UPBGE on my FreeBSD box it is a Blender fork with BGE still active: https://upbge.org/

I forgot about that.  Yes that's a way to go, but building on FreeBSD is going to be fun!

UPBGE is now working on FreeBSD. However it does not run all Blender 2.79- applications / scripts correctly so it's NOT 1:1 replacement. I need to stay with 1.79 :-(

you might want to have a look at Armory 3D too

At some point in time, an "interactive mode" was in discussion/announced. But it seems this was dropped, according to a statemen at Blender Conference 2019. You can check some discussion at Blenderartists:
https://blenderartists.org/t/any-news-on-blender-2-8-interactive-mode/1178594

Thank you. Did put my two cents over there. Blender lost my Respect and Trust. New team just removed something that was there for 25 years with no replacement no alternative and it looks there is even no plan for alternative. SO LAME! :-(


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After the Version. 4.2 of Blender my capture attribute node seems to be broken?
Is it me or the node seem to be changed. I checked the setting in the panel but it was not working? Any solution?

https://blender.stackexchange.com/questions/323084/capture-attribute-node