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What does it mean to call applyimpulse on a point outside the object?
I have a 1x1x1 cube in the scene and apply an impulse to point [20.0 0.0 0.0], which is outside the cube using applyImpulse function, but the cube moves. Could someone let me know what it means to apply the impulse to a point outside the object? I expected that the object does not move if the impulse is applied to an outside point.

Force at center
When you apply a force to the mass center of an object all the energy of the force will turn into a translation.
Force outside of the center
If you apply a force at a point outside the mass center the energy will turn into a translation of exactly that point.
Be aware each point of the mass want to keep their momentum. This acts like a counter force. That means there is a stronger counter force towards the mass center as there is more mass then of the other side of the point. The result is mix of angular and linear motion summed up by all forces (including the momentum).
As more far away the point is as more of the energy will result in rotation. As nearer the point is to the center of mass as more of the energy will result into translation (to the maximum of all energy goes into translation and nothing into rotation).

Question

[...] what it means to apply the impulse to a point outside the object?

It does not matter. The physics model does not care your mesh. It uses it to define the dimensions and collision but not to calculate forces.
You can applying a force anywhere in space. It is assumed this force should be applied to the object (otherwise you would not try to apply it). This force will be taken into account when calculating the final linear and angular motions.
Keep in mind: This is a game engine. The physics engine is designed to provide fast but believable results. Checking if a point is outside of a surface mesh eats a lot of processing power and is not necessary. If you really need such check you can do perform it with some Python code.
I hope it helps a bit.


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save avi files in blender using python script
I have created an animation using Blender. Does anybody know how I can save .avi file of the rendered animation using a python script?
My second question is that I want to run the animation with different parameters and save the video. Basically, I want to reset the animation and run it again with a new force and save a separate video file. I want to do these automatically instead of manually. Is it possible to do that with scripting?

Assume by animation you mean image sequence ?

Also asking 2 questions at once isn't good, best just ask 2 separate questions.

bpy.context.scene.render.filepath contains the filename that the render will be saved to, you can change this and then use bpy.ops.render.render(animation=True) to render the animation to the specified file.
import bpy
bpy.context.active_object.material_slots[0].material = bpy.data.materials['Red']
bpy.context.scene.render.filepath = '//red.avi'
bpy.ops.render.render(animation=True)

bpy.context.active_object.material_slots[0].material = bpy.data.materials['Blue']
bpy.context.scene.render.filepath = '//blue.avi'
bpy.ops.render.render(animation=True)

The // at the beginning of the filename puts the file in the same folder as the blend file.

source: Stack Exchange

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

sort: votes


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Morphing low poly object to high poly object
I have multiple high density head models and one low poly head model. The high-density models are different between each other in details like mouth expression. I'm looking for a most efficient way to make the low poly object as similar as possible to one of the high poly models.
I'm well aware that there could not be a method that will do it perfectly for any sample high poly model, so I allow it to be succeed by minor fixes by hand.
The first thing that came to my mind was to do simple retopology with snapping. The result would be nice and accurate, but it's made by hand all the way and I'm searching for something batch-like. Is there a way to do it more automatically?

Look at this question. It is not like batch (for that you need to use python) but it is very simple so you can do that with multiple high-poly figures on one low-poly figure. Notice that with that method it only looks as close as possible like the high-poly figure but the vertices don't change.

Use the shrinkwrap modifier. First set a Shrinkwrap modifier to the low poly(make sure it is in the same place as the high poly and larger than the high poly) then set the Target to the high poly with settings set to Nearest Surface Point.

Shrinkwrap will propably be my best shot. Thank you:)

Good to see it worked out for you. :)

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


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Ambient Occlusion and Volumetric Lighting
I am right now doing an interior scene for a customer. For trying out some stuff I thought about volumetric light. Unfortunately I can't get it to work thought I used it before successfully. My thought was, that the ambient occlusion got something to do with it. But even turning AO off won't show the known volumetric effect.
Since the scene is quite huge and has a LOT of linked objects I can't share it that easily.
Now this is no must have and I am short on time and I am just curious - I won't try out a lot (later perhaps) and therefor just asking  :)
Does anyone know anything about an interaction between these two?
Thanks in advance!

If turning off AO doesn't allow you to preview volumetrics why do you think AO is somehow involved? It's hard to judge only on description, at least some screenshots could make it easier. For now the only detail in your question about actually problem is "I can't get it to work though I used it before successfully" which is quite vague - what doesn't work?

You don't have to necessarily use images from your project. Try to reproduce a basic scene and use that, maybe you might even solve your problem in doing this. See this meta post on how to better ask questions - https://blender.meta.stackexchange.com/questions/608/how-do-i-ask-a-question-that-is-hard-to-describe/609#609

Yeah, I know it's not precise, sorry about that. Asked out of curiosity if anyone knows something. I will get back to it and will try to reproduce it when I got more time.


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Straight line draw animation how doing it?
I am trying to do something simple yet i haven't found a way to do it in blender that is animating the drawing of borders of a shape (rectangles, triangles...) you can see an example on youtube of the result i am trying to achieve :
How to Animate Shape Borders in Adobe After Effects CC (2017)
If anyone has a good technique to do it or a blender file it would be cool.
Thanks.

You can add a Bezier Curve and make it any shape you want to. SHFT +A > Curve > Bezier.

"Extrude" it to add some width.

Then Animate the start and/or end of the Bevel Factor. Hover your mouse over the Start or End input box of the Curve press I move the Playhead in the Timeline, change the value and hover your mouse over the Start or End input box press I again.

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


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Movie clip node as mask

I am trying to do something simple but i encountered a problem i can't resolve. I am using a movie clip node as a mask  which last 30 frames in the compositor. For the 30 first frames it works well but right after the 30th frame the movie disapear. I would like to make the last frame of the mask movie clip last to the last frame of the render movie.

Thank you.


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Rookie question about ne Blender 2.75a rotating view
I just upgraded from 2.72b to 2.75a and now I can't rotate my view with my mouse anymore. Even if i hold down the shift button, it wont change my view either. I have tried changing the free/trackball option in User Preferences, but it doesn't do anything. Any advise?

That's very strange.. Does enabling Emulate 3 button mouse and using Alt+LMB instead of MMB do anything?

doesnt appear to do anything

Hm. Have you tried reverting to factory settings?

Yes sir, ive tried that several times. I will re'install it all, see if that makes a difference.

Got it working now, and followed your advice for the Alt+LMB - it works! Thanks for the help :)

Well, MMB  should work, unless there is something wrong with the middle mouse button on your mouse. If MMB still doesn't work but Alt LMB does, you might want to try it with a different mouse.


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Animating Issue
I'm really new to blender and am using it to model and animate for a game i'm currently working on.
Could someone please explain how to "properly" animate something in blender.
What I do is go into the action center click the record button and animate like that. However when I do so I get a whole bunch of junk files. I want just one clean animation with all the movements included. This is more of a nuisance than a problem.
Any help would be appreciated, thanks.

Well, "properly" is subjective and will depend on what is being animated and who you ask. Perhaps you're wondering how to insert individual transform keyframes manually (I)?

With just about anything one can do in Blender, including modeling and animating, there is often more than one way to reach the same end. This is as true of animations as it is of anything else, and means that there is not really a good answer to

how to "properly" animate something in Blender

because how one proceeds with the animation depends upon not only what is being animated, but how what is to be animated is made, and how it will be used in the scene, to name just three considerations. You haven't provided any of that in the original question. You also don't provide any images of what you want animated, and what you want the animation to do, and how you want it to look.
My sense is that maybe you are trying something beyond your current skillset. There is nothing wrong with that, but this is not the place to enhance your skillset directly. If I were you, before trying to animate the object, I'd visit question, check under "online courses", and consider working through one or both of these. I think this will give you a good foundation towards what you want to do.


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Blender won't finish rendering
When i try to make my intro, my blender keeps on rendering and then when it's done, it starts all over repeatedly. I waited a while and it keeps on doing the same thing for like an hour.

it looks like you're rendereing an animation, try rendering a single image/frame (F12 or render menu->render image)

As said by Bithur in the comments, it is quite possible that you are rendering an animation. Stop the current render with the Escape key. Then press F12 (make sure that you don't press Control+F12 by accident!), or go to Render -> Render Image from the toolbar.

If it continues to do the same, go into the render settings and make sure that Sampled motion blur is unchecked. If even this doesn't help make the render finish, uncheck Anti-Aliasing (I am not really sure this will help, but you can try...).

Is there any chance this answer getting accepted?


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Radar simulator
Do you know if I can do something like a marine radar in blender, detecting figures in the world (like cubes moving around) and showing them in a display. (seeing both, the radar display and the world). Like in a FPS game :P.

do you basically want a mini-map with the cubes?

yes, something like that, but with a "real" map, can you help me please??


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Can I generate the difference between 2 texture seeds?
I am making an animation with water. I am using textures for the water (of course). The problem is, I want the water to move. When I change offset or size etc. you can very clearly see it moving. When I try to get the difference between 2 seeds, it generates the seeds in between (ex. 1->2 becomes 1.1->1.2->1.3). What I want is that it takes 2 points (1->2) and then generate the difference between those points, not the seeds. Help is very much appreciated!

maybe using shape keys

It's not very clear what you are asking could you post some more info, maybe an example image of what you want, some screenshot of your scene or even the blender file itself? Are you using image bases textures or procedural textures? What 'seed' value are you talking about? How are you animating it?


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Rig with joined objects
I have followed some tutorials and created a nice cartoon looking shoe. That shoe has three different objects(shoe itself, shoelaces and lace holes). I joined them together and everything was fine until i wanted to test rigging. when i added some bones for testing those laces and holes doesn't deform with the shoe. what might be the problem?
Without Rig:

With Rig:

You didn't weight paint the newly joined parts of your mesh. Also see https://blender.stackexchange.com/questions/8227/some-vertices-dont-move-along-with-the-rig/8228#8228

@DuarteFarrajotaRamos thanks for the setting me on the right direction.I will check them and update with results

@DuarteFarrajotaRamos i checked weight paints and it was ok but turns out i had to set vertices those to bones as pointed out in the first comment as you said. it helped me to figure out thanks alot.

The problem are weights. each part of the mesh gets weights automatically by assigning the armature modifier, but these don't work with intersecting objects like yours. It's almost impossible to assign proper weight to cloth details like this manually.
To solve it, try to use Mesh Deform modifier:

make a very simple mesh around your model.
add Mesh Deform to your original model, bind it with your mesh.
add bones to your simple mesh.


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Distorted blender UV face unwraping
here i try to unwrap this face and i get faces unwraped randomly.
tried to search for solution but all i found was for versions earlier than 2.77 and as you can see im using 2.77, where some options are in different places and some are not there!

Can you upload your .blend using our friendly service known as http://blend-exchange.giantcowfilms.com/

You need to mark seams somewhere before the model can be unwrapped. Select edges and hit ctrl-E -> mark seam

What is your goal?
Do you have a texture already made?
Are you planning on painting a detailed one?
Does the texture need to look right from all angles?
UV unwrapping a face has similar problems as trying to put a map of a spherical planet onto a flat piece of paper.
Lots of different ways of doing it but some distortion is inevitable.
here are some different possibilities: https://s-media-cache-ak0.pinimg.com/736x/6e/52/e7/6e52e71165b3cd4527c6b5f00ac103dd.jpg
here is a tutorial https://www.youtube.com/watch?v=W-ZmDKuB6HI

the model came with textures so im trying to unwrap it so i can modify it or repaint it

a little tip to use already found solutions. you can easily use as many versions of blender as you need. it doesn't need any installation. just download earlier version in another folder and run it from there. this way you can use solutions for previous versions, save your file and then continue in your favorite one later.
it's not so weird as it sounds, at least for blender. it can do some things better in the very version only.


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molding an object in the shape of another object
im trying to create a daz custom face morph. i have a custom face from another model i want to apply it on the genesis 8 fem model in blender. but i cant cut and past it straight away because i need to preserve original model vertices count otherwise it wont import into daz as morph. so im thinking perhaps there is a tool that molds an object in the shape of other object without changing the vertices or polygons count. i already extracted the custom face mesh. now all thats left is to mold the original genesis model face in its shape. something similar to how clay molds work in real life.

If I understand your question correctly,you are looking for the Shrinkwrap-Modifier. Add the modifier to the model you want to change and choose your "desired face" as the target. For further reading consult the manual.
However there is no way to get more detail than your polycount allows. That means the Shrinkwrap-Modifier might produce artifacts if the polygon-density of your model is far less than that of your target.

TheBeautifulOrc technically has the right answer. However, based on my personal experience, I would say that the shrinkwrap modifier, while very useful in some cases, could be problematic in your case. It may actually be easier to take the Genesis 8 model from Daz Studio, import it into Blender, take your custom model also, and import that into the same scene in Blender, and then use the custom model as as a visual reference only while you try to actually manually sculpt the changes in shape onto the Genesis 8 model directly. Depending on how much of a difference there is between the two to begin with, this may not actually be a lot of work. It may actually turn out to be very much MORE work trying to get the Genesis 8 model to take on the exact shape of the custom model instantly by relying on a shrinkwrap modifier. This is because, more than likely, the various parts of each face and head is just not going to line up, no matter what you do, leading to the possibility that one will end up crooked and smashed against the other in a terrible way that you just can't seem to fix. So this would be an alternative approach, IF you need it. :)

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


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How to use an Emoji font with Blender?
Here are some Emoji:
http://getemoji.com/
These Emoji can be easily copy/pasted into Microsoft Word on Windows.
I am encountering a world of hurt by trying to get any of these to work with Blender.

You can start with large screen shots from your text editor, vector trace them in Inkscape, then import the SVGs into Blender.

To use an Emoji font in Blender as a font, first one must have the font installed on the computer. Do a search, using your favorite search engine for "emoji font", appending either "ttf" or "unicode" according to your preference, and download and install one of the fonts you locate by that method to your computer, as you would any other font. Now, the font should be accessible in Blender in the same way any other installed ~.ttf or ~.unicode font is accessible.
If you don't know how to have Blender make use of the installed fonts on your computer, this tutorial may be useful.

Change the font - the only font working for me is the pre-installed Segoe UI Emoji Regular.


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I can't add a texture to my models
I'm trying to add a texture to my model. I'm following some tutorials om YT to know how to do it, But my blender doesn't do what it should do.
I can't add the correct things in the node editor:
This is what my node editor displays by default:

This is what it should display by default:

Also I can't add a image texture box in my node editor.
I hope someone can help me out on this. :)

At the top of the screen, it says Blender Render. Click on it to open a dropdown menu and select Cycles Render. Cycles is what you are looking for and utilizes nodes. Blender Render does not.

Oh that was such a small thing. Thank you so much :)

Blender Internal does use nodes, however Cycles and Internal are just completely different. See how they are different

That's probably because you are in Blender Internal,
try switching to Cycles.

Please add detail to your answer, explaining how to do that. Like, an image and/or text.


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Stamp plane UV onto a mesh
Im using blender to change some premade assets for our game. I want to move a window. Here is the original mesh and UV The texture is planar and flat so it matches 1:1 to the shape of the 4 outer vertices on the mesh.

Here is the new mesh, I have tried to manully adjust the window UV mapping. But get errors

But offcourse I end up with errors, here in Unity

There is probably a super easy solution to this, sorry for being a noob

The distortion you are seeing is the result of the mesh and the UV maps not sharing the same proportions. Here is one method for achieving your desired effect, but it assumes that your texture is only for the wall, and that the four vertices of the window don't have to be in a specific place on the texture.

In Edit Mode, press Shift+D with your mesh selected to duplicate it.
Move the window to the desired position.
With the duplicate selected, press U to unwrap it.
With both meshes selected so you can see them unwrapped, position the newly unwrapped mesh above the old one. This can be achieved in a number of ways, but one ways is as follows:

Select old wall's bottom left vertex on the UV map, and move the cursor to the selection.
Using Vertex Snap: Closest, position the new wall on the UV map such its bottom left vertex aligns with the old wall's.
Set the pivot point to cursor, and scale the newly unwrapped wall until all of its vertices align with the old wall. Make sure you are always scaling the whole wall, including the window vertices.


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Blender 2.82 how to get linked edges
Im trying this for edge in vertex.link_edges: but gets

'MeshVertex' object has no attribute 'link_edges'

Thanks

Hello ! link_edges is a member of bpy.types.BMVert, not bpy.types.MeshVertex. ie you need to use a bmesh, not a regular mesh. https://docs.blender.org/api/2.82/bmesh.types.html?highlight=link_edges#bmesh.types.BMVert.link_edges Please add a bit of context to your code so we understand a bit better what your script does. Cheers

Im trying to analyze a mesh for local variation. Its a game terrain. I need to find open terrain and vice versa


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Keep only geometry with certain amount of height difference
I'm trying to post process a navigation mesh that I will send into a another product for baking audio environment data for our game.  If I send in the entire navmesh for the terrain it will take weeks to process. So I want to send a navmesh that only contains non flat geo. Hills, etc. And also a buffer zone around these zones. Can I use Blende to automate this process?
I basically want it to select all hills with a little padding, and So I can invert it and delete that geo. Or vice versa.

Maybe use Select Similar > By Normal?

You can select a flat face, Shift+G > Normal to select all faces with similar direction, Ctrl+Numpad- to contract the selection for the buffer and delete them. You can do similar things in Geometry Nodes dynamically: https://i.imgur.com/u4mdRI7.png But I'm gonna guess you wouldn't want the result to be so patchy, right? You kinda want it to recognize that sth is a hill even if small parts of it are flat and preserve it as a whole? That'd be much harder.

@Kuboå Yeah I would want it to use some sort of local maxima (local peak) threshhold. Ideal I would just change a threshhold and see the selection of quads change That would be a easy workflow

A Geometry Nodes setup (or a Python script) like I've shown would be dynamic, but the math of adding locality considerations is above my paygrade unfortunately. You could have a go at that if you're alright with the math.

@Kuboå Im a programmer. But then I might do it directly in Unity game engine instead which Im familiar with.  It would be something like https://stackoverflow.com/questions/22218037/how-to-find-local-maxima-in-image

you can smooth and expand / contract selections in vertex paint mode... and maybe those flat zones are on a certain height range? that could be part of the selection mecanic...


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CUDA option not shown when using an old GPU
It looks like this is a common problem, but I can't find any forum post that has a solution to my situation: I have no CUDA tab in system settings in Blender.
My data:
Windows 10 64bit
Blender v2.77
Geforce GT 330M - driver Nvidia 341.95 (newest avalible driver.)
Is there someone who can help me to find out what can be the issue?

Just to be sure, have you tried everything outlined in this post?

What kind of hardware are you using, notebook or desktop / tower? Going to this nvidia page, and clicking to expand the section "Cuda enabled GeForce products", I don't see that the GeForce GT 330 M included in the list.

i am using notebook on my notebook is a sticker saying Geforce with CUDA. so i suppose that it is supported. i can also finde CUDA settings in the nvidia control pannel.


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Can't use "L" Key to select an object, selects vertices instead.
So I've got my character model divied up, and I can select all of his limbs that I've split with the "L" key. But when I try to select his left foot, it simply will not select the whole foot. The right foot is totally fine. But the left will only select a face if I press L over it. I've tried on all areas of the foot but it still will only select the individual face. Here is a picture of what the right foot does when I press "L" over it, and what happens if I do the same on the left foot.

Could you share your .blend file?

It sounds to me like you have double vertices (each face in the left foot is separate). Does select all then W > Remove Doubles fix it?

It mad ethe whole body become selectable including both feet. I assume this has fixed the problem. So now I'll just go back and split that foot off again. Thanks for your help.

@gandalf3 the problem is visible in teh screenshot. set to "Seam" for teh select linked setting, not "Normal" as it should be.

@ARadish According to the OP, the right foot (the one with the seams) is working as expected. There are no seams on the left foot, which I take to be the problem foot.

It could be that you have double vertices; multiple disconnected vertices in the same location.
If each face in the left foot is separate, it would result in symptoms like these. Try removing doubles by selecting everything (A) and pressing W> Remove Doubles.

This is because the "select linked" setting is limited to "Seam". you can see this setting in the toolbar on the left margin. This make the "link" looks for edges marked with the red (UV unwrap seams) as the dividing line for the selection. See my picture, how the red seam splits what vertices are selected.

Try instead setting it to "Normal" this will go lack to the setting you are more used to, where it selects the entire object(s), regardless of UV unwrap seams.

On second glance, this looks like it may not be your problem, but it could be. lol


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Is there a way to write images from render process in batch mode
I want to save pictures from a rendering startet from command line in background mode. To save the final picture is not the problem, my question is, how to get pictures from the render process.
In gui mode I can view the iterations while blender cycles renders my scene. In background mode I only get the final result. I want to get these unsharp images, You know? Sure, I can save all these steps with growing cycles settings, but with this, the render time will grow also.
Do You have any ideas to solve this "problem" without multiplying the rendertime?
Thx for Your time,
Peter.

Think this is possible in current master now (brand new from early 2016 April ;) ).
Basically, if you run:
blender -b yourblend.blend -f 0 -- --cycles-resumable-num-chunks 24 --cycles-resumable-current-chunk 1

…you say Cycles to 'split' the render (its sampling actually) in 24 'chunks', and only render the first one.
Then you can use a script to keep that picture (by copying it e.g. to a new name), and render the second chunk, etc.
See also original commit log.

The reuse of renderresult defined by the given chunk would be helpfull. To start a new rendering with the following chuck is not the way I want to go. I want to have nearly the same rendertime from start to final result with the output of single-chunk-renderings while it renders. Its a must-have condition.


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Different renders of different objects with the same materials
I need to make some renders of different objects with the same materials. Each object needs to be rendered alone from different angles and they need to look alike because they are built from the same materials. Also, the lightning should be the same (I'm using environment lighting because the objects contain some glossy parts).
I was wondering what is the most efficient way to accomplish this; if I should put them all in different layers in the same blend file with linked materials and switch manually the layer each time to be rendered, or if I should split them across multiple blend files and somehow link the material + environment light, or if I should use different scenes (I don't know how this works), etc.
I'm using Cycles.
Thanks for your help =)

Depending on how many objects you have, I would put each object on its own layer in the same blend file. Keep them all at (0,0,0,) and just turn off/on which one you want to render. If you have more objects than layers I would put them all at (0,0,0) and turn off the camera icon in the outliner so it doesn't render.

Thanks for your comment! Is there any way to batch render all the layers?

Yes I believe there is a way but you would have to find a Python script to take care of that for you. I am a novice at Python so I don't think I would be of much help. Im sure some of the coders in the forum could help you out.


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How can I queue different blender actions to be rendered?
I'm designing a character with different animations (idle, eating, walking, etc) that are separated in different blender actions in the same .blend file.
I would like to queue the actions to be rendered, so I could leave the computer rendering over night. Is there any way to do that??

There is nothing built into Blender that will batch or queue renders, at the moment.
The simplest, most portable way is to make an animation that consists of those actions one after the other. Render the whole thing to frames, then take the first set of frames for one sequence and render it into a video. Then the next sequence, and so on. Depending on how sophisticated you want to be, you could even make a new Blender file, link (or append, but link would be better) the actions into a new file, and set them up to play one after the other. Then render that one, instead of modifying your original file.
Another way, for things that aren't or can't be in the same .blend file, is to launch Blender from the command line using some kind of command-line script like a batch file on Windows, or a bash script on Nix or Mac. E.g.
cd c:/<blender folder>
echo Rendering the first one...
blender -b filename_one.blend -a
echo Rendering the second one...
blender -b filename_two.blend -a
echo Rendering the third one...
blender -b filename_thr.blend -a
echo Done rendering.

The most robust, but most complicated, way would be to write a Python script that launches Blender with certain command-line arguments. A Python script could be programmed to choose certain arguments based on certain criteria. It could check to see if there are as many frames as there should be in the results, and if there aren't maybe run the render again with overwrite turned off. Interesting things like that.
I hope that helps!

Thank you for your reply! Unfortunately, I need the image sequence, not the video, as my final result; so if I put all the actions (there's a lot) in the same timeline I would need to rename every corresponding block of images in order to get the enumeration right. If don't find an easier way, I think I will try your second suggestion and divide everything in multiple .blend files, so I can batch render them.

The first suggestion produces just an image sequence, just don't go on to the last step ;-) But yeah if you've got more than 4-5 actions, it would be SUPER tedious to go through and manually select each group of frames. OOOH! OH!!H!O!H!H! I JUST HAD AN IDEA!!! Lemme go see if it'll work...

Nevermind :-( I was thinking that you might be able to animate the Path of a file output node so that you could have the name change for certain frame ranges, but you can't keyframe it.

=(
I was excited with your epiphany moment hahaha.
Thanks for trying!!

I have a solution for this problem.

for each action, set it to active action
after that, perform render

    import bpy
    obj = bpy.context.object

    for action in bpy.data.actions:
    obj.animation_data.action = bpy.data.actions.get(action.name)
    print(obj.animation_data.action)

    bpy.context.scene.render.filepath = action.name+'_'
    bpy.ops.render.render(use_viewport = True, write_still=True, animation=True)

run line by line in your blender file, console mode.
Please note that I tried to run it as a script and render by command line, but it did not work.
blender -b xxx.blend -P render_action.py

People should answer questions like you!


text:
How can I view my scene using the Oculus Rift CV1 and the OpenHMD branch of Blender?
On Graphicall there's a branch called OpenHMD, which basically should enable Blender to interact with VR glasses like the Oculus Rift. I do have a CV1 (consumer version) available, as well as a DK2 (development kit 2). When running the branch, I can open an OpenHMD window just fine, and I can also start the session as expected. The tracking even works well, when I move the Oculus, the viewport updates. Here's a screenshot:

But the Scene is never drawn on the goggles. I've followed the instructions of the manual here regarding switching the device to immediate mode. But that should mean I need to somehow move that window over to the Oculus. Thing is: I can't do that. The window snaps to all screen boundaries, I can never move it off-screen so it would show on the Oculus. Any ideas welcome.

Assuming you are using Windows:
The way to enable this is to switch the Oculus in Extended Mode, this is done by running a specific tool that Oculus delivers with the driver (example is https://www.reddit.com/r/oculus/comments/4nvy7o/rift_dk2_possible_to_activate_extended_mode/).
Opening the HMD window in Blender should start the display in extended mode, if you can not view your desktop through the Oculus before moving the window, It is not activated correctly.
When using Linux:
If you are running Intel or AMD, this should work fine out of the box, with Nvidia, if you have recent drivers, you may need to enable Extended mode by adding AllowHMD in your Xorg, instructions can be found here: http://us.download.nvidia.com/XFree86/Linux-x86/378.09/README/xconfigoptions.html

Finally had some time to test it out. I am on the Windows Platform, and following the reddit link from up there gave me the same instructions I had already known. The key point however was that you need to turn DirectDisplayConfig to OFF in order to make OpenHMD work. Also its location seems to have changed: On my system it's in "C:\Program Files\Oculus\Support\oculus-runtime\DirectDisplayConfig.exe"


text:
Curve to Mesh - Not all faces are not connected
I have a Bezier curve, which has the following settings:

When converting this to a mesh, in Edit Mode, some of the faces are connected and others are not. Not sure if this is intended, but is there a way to convert it, where all the neighbouring faces are connected?

This is the original curve

Here the curve has been converted to a mesh, with two vertices raised upward. You can see that one is connected, and the one selected is not.

After you convert the curve to a mesh,

Tab into edit mode
A to select all vertices
Hit W and choose "Remove Doubles"


text:
Rigged mesh deformed after opening blend file
I have a linked object in a master file. I then create a proxy of the rig, and everything works as expected, I then save and close the file.

But when returning to the master file, the mesh is completely deformed.

If I put the armature in 'Rest Position' or remove the armature modifier and re-rig the object from scratch, I no longer get the problem.
The object in the linked file has scale and rotation applied, and the armature seems fine as well (using rigify). I'm new to working on a large scale project and using linked objects, so is it possible a step could have been missed, or if this could be a bug? (Using Blender 2.78c)

do you see a button next to the render enigne selector that says "reload trusted"?

No, there isn't that option

I am new to blender so i dont know how much or if at all this will help.
I have the same type of problem with my mesh being disfigured after opening the saved file. Below attached link helped me save that rig without getting the mesh disproportionate. LINK: https://www.youtube.com/watch?v=o6_AzySr64c&t=400s Hope it helps
Cheers

As Firewill noted, it is a standard problem with python scripts. By default, Blender disables running scripts from scene, because downloaded scripts may contents malware.
So, to run this scripts you mast press "Reload trusted" in header of window, to confirm that blender may trust scripts:

If for some reason, you haven't this buttons, there is a workaround: Open User Preferences, in File tab click auto run python scripts:

In this case it is recommended to add a downloads path as Excluded.

I see what you and Firewill have pointed out, but unfortunately, this is already enabled.


text:
Select vertices on one side of a cube
The aim is to select the vertices of one side of a cube.
My intention was to change the view's orientation using bpy.ops.view3d.viewnumpad and then select the vertices that are visible, using bpy.ops.vew3d.select_border.
    def changeView(view):
               for area in bpy.context.screen.areas:
                 if area.type == 'VIEW_3D':
                     override = bpy.context.copy()
                     override['area'] = area
                     bpy.ops.view3d.viewnumpad(override, type=view, align_active=False)
                  break

    def select_border(mesh,context, view3dAreaAndRegion=None, extend=True):
          if not view3dAreaAndRegion:
            view3dAreaAndRegion = getView3dAreaAndRegion(context)
          view3dArea, view3dRegion = view3dAreaAndRegion

          override = context.copy()
          override['area'] = view3dArea
          override['region'] = view3dRegion

          #change orientation to Front side
          changeView('FRONT');

          bpy.ops.view3d.select_border(override,
                                       gesture_mode=3,
                                       xmin=0,
                                       xmax=view3dArea.width,
                                       ymin=0,
                                       ymax=view3dArea.height,
                                       extend=extend)
           return view3dAreaAndRegion

This works, so long as I click 'Run Script' twice, or if the View is already set manually by hitting 1 on the number pad.
However the problem is, if I pan around,then hit 'Run Script' once, it selects all the vertices that are visible from that angle, before changing the view's orientation to Front.

If using predefined options, you can try Select > Side Of Active and set up its options (Axis of selection, Positive/Negative etc) or Shift+G > Co-Planar (in face selection mode), it might be similar to your needs.

Comparing face normal to views' normal could be another way to do this without operators. Also Related

You could use some vector math to select the right facing verts (deselect all verts and run this in object mode in the text editor, or paste in the console)
from bpy import context as C
from mathutils import Vector

for v in (v for v in C.object.data.vertices if v.normal.dot(Vector((1,0,0))) > 0):
    v.select = True

alternately, to select the left side, change the Vector to (-1,0,0). Top, (0,0,1) etc.


text:
Best way to create a hole in a mesh?
I'm modelling a minigolf hole but when i create the hole with boolean modifier i see a little drop around it.
This cause the ball in the game not rolling straight as it should.
How can i solve this problem?

Please add images to your post to show what you have so far.

Here's a link to a video showing different hole-cutting techiniques https://www.youtube.com/watch?v=Bc52fcrHvAA. Obiuvsly there is not a "best", each one has its pros and cons, each one is preferrable for one situation and not for others. Could you better describe yours? Maybe with a gif/video/blendfile...

Does "the ball in the game" mean this is a BGE question? Or are you using some other game engine? I'm guessing the boolean approach is not the best solution for your task. Maybe creating a hole with proper topology (maybe an octagonal hole with holding edges, subsurfed?) could be a better solution? You haven't provided many details about your geometry. Uploading a .blend would help us to help you.

Trying other hole-cutting techniques i've found a possible solution to my problem. Thank all anyway


text:
Set color attribute of selected vertices/vertex group
I want to store different colors per vertex group in an attribute map.
All assigned verts in vertex group1 = green
All assigned verts in vertex group2 = blue.
On my test cube all top vertices are selected and in a vertex group called selection and should be colored green.
Best I could come up with is with a separate geometry node,but this makes me lose the edges between top and bottom of the cube.
And also is limited to selection and inverted selection instead of multiple vertex groups.

What's the best approach here?

Use a switch or a mix node:

...

That works, how do I introduce a third or fourth color based on a vertex group selection?(assuming there are no overlapping vertex groups)

@Tortenrandband by making a tree of switches.

That works (but feels clumsy compared to python api, but I'm still getting used to geo nodes and I really like the fast viewport preview of GN)

@Tortenrandband In Blender 4 you can use a repeat zone, but you still need to somehow provide the names of vertex groups, so if there's just a few of them, multiple switches seem like the easiest solution.


text:
Viewport colors look darker in Vertex Paint mode Blender 2.8
Viewport shading set to solid and color to vertex with flat shading,
the colors appear to be darker in vertex paint mode than in object mode.

By default vertex colors get multiplied when entering vertex paint mode.
Set opacity of vertex paint mode overlay to 0 in viewport overlays to make object and vertex paint mode look the same.


text:
Colorize Instances according to vertex color or UV map
I have a vertex colored model (1) and I'm using Cells v1.2 to generate a hollow voxel model of my Object.(2)
I want to change the object color of every instance/voxel according to the underlying vertex color or UV map.
As shown in picture (4).

In this stackexchange post the instance inherits the color from the emitting vertex.
Tricky part is that in my model the instances/voxels don't line up with the underlying vertices of the original model. Seen in picture (3).
How do I find the nearest color for every instance?
The result should consist of separate objects with its own object color.
I want to export every individual color as an .stl file.


text:
Writing to internal textblock is slower than writing to external .txt file
Writing 20million entries to Blenders internal textblock takes 38sec.
Wiriting to an external .txt file takes 29sec.
import bpy
import time

tb = bpy.data.texts.new("text_block")
txt = open(bpy.path.abspath("//")+"vertex_data.txt", "w")
then = time.time()

for i in range(20000000):
    tb.write(str(i)+"\n")
    #txt.write(str(i)+"\n")

#txt.close()

now = time.time()
print(now-then)

I like to keep the custom data in the internal textblock of Blender,
is there a way to speed this up?

Imagine   tb.write("\n".join(map(str,range(2000)))) would be quicker in both instances.

That worked, time is down from 38sec to 16sec. What is the trick here?

Writing only once. Also see String addition - this is the slowest option, don’t use if you can help it, especially when writing data in a loop.


text:
Access Face Set color in bpy
Is there a way to get the face set color of a polygon via python?
The face sets are new to Blender sculptmode, I like to transfer face set color to sculpt vertex colors.
bpy.ops.sculpt.face_sets.. has operators, but there is no way to access the data like obj.data.face_sets..

Blender 3.4 lets you access sculpt face sets via a custom int data layer.
I don't think you can get the color itself yet, but can access the face set index like this:
import bpy
import bmesh
obj = bpy.context.active_object
bm = bmesh.new()
bm.from_mesh(obj.data)
custom_data_layer = bm.faces.layers.int.get('.sculpt_face_set')
for face in bm.faces:
    print(face[custom_data_layer])


text:
Timeline drag is jumpy and unusuable
I'm unable to consistently drag the frame indicator on the timeline, or the dopesheet, or the vse, or anywhere the timeline is available. The cursor keeps jumping back to the previously selected frame. Sometimes it works, sometimes it doesn't. I'm able to change frames with the 'current frame' field, but that's a pain. I have to restart blender.
Here is a link to a youtube video of the problem: https://youtu.be/h-fJN3gSkuY

i am not sure, but did you try set "no autosnap"? [1]: https://i.sstatic.net/hIqs7.png


text:
Controlling the scale of objects without distortion when tapering arrays on a curve
I want to find a way to scale an array of objects along the curve, such that the scale of an object is proportional to the position on the curve, or can be adjusted along its length.

With my understanding of the Array and Curve modifiers, the object will be positioned based on its proximity with the next object in the array. I'm able to change the radius of the curve at its points and this does scale the array at that point, however only at the axes not following the curve, so this produces ellipsoid at that point.

I've tested out the object offset option on the array modifier, using an empty at the origin point. It produced the taping spheres that I was looking for, but that only did the scaling one way and no longer respected the length of the array.

Also related https://blender.stackexchange.com/questions/68923/torus-object-stretched-in-array-curve-modifier/68925#68925


text:
selection vertices by user's value
I have a mesh (like a city mesh) referenced to the origin (X=0,Y=0,Z=0) and i'd like to select all vertices with value Z=237 (i'd say to the computer) and X=129 (i'd say to the computer) Y=any, for example (is like select the thirds floor from all buildings). How could i do that.
PD: Or edges , or faces, or from several objects

@MrZak I think the OP is referring to a large model where it would be difficult to eyeball the correct selection range in the viewport, so he would like to use some kind of numerical input to define the boundaries of the selection box.

Ok Carlo. The example is clear, all vertices with X=129, Y=any, Z=237 in a big city mesh.


text:
Unexpected color flattening
I am fresh to Blender and am making a futuristic-ish flying vehicle network. There are rows of rectangle groups all moving in different directions while the camera pans the scene.
In an arbitrary frame (which is around the middle of the animation, but NOT always the same frame), all objects are suddenly de-colorized and turn white for no apparent reason! Some seconds later, it returns to normal. This happens ONLY in camera perspective!
I've deleted the camera and re-added it to no avail. This is exactly how it looks:
Normal (with colors) in render view:

Problematic (white flattened) in render view

Any ideas????

Cycles or internal? How is your material applied? Is any of your colour vertex colour? Could you post photos out of render view, or even post the .blend if your comfortable?

Are the colors also 'flattened' when you render the scene? Are you doing any compositing? What kind of material have you given the objects?

@360ueck I use cycles. And really comfortable posting the .blend file because i am not sure if i can give you the appropriate info...!

@Cubit The objects are glass bsdf surfaces and emission volumes. About the compositing part, not sure i can enlighten you...

https://www.sendspace.com/file/vfzwul the blend file...

@Cubit No, the verdict is that I am not compositing on this scene... I think...

You need to turn up your "saturation" and "value", otherwise it's mostly white glass and light. Add that to the extra emission from lamps and other objects and the cars just appear white at times.

Totally noobish mistake...! Really thanks for the help!!!! :D


text:
Export Animations to Wikitude
I am trying to export a scene to Wikitude 3D Encoder. The scene is nothing special, for now a simple cube will do. However, I would like to have multiple animations available for this object which I can then later on trigger in Wikitude.
I found that using the NLA Editor will give me multiple animations in the FBX file, and they also import into Wikitude. However, only the last animation is used, no matter which one I trigger.
To be clear: I define a separate action for Move, Rotate and Scale cube. I create an NLA track for each. I export to FBX and import into Wikitude. I do see three animations there, but no matter which one I click, I only see one of them executed. It is the one at the bottom in the NLA editor, in this example the scaling. So when I execute 'Scale' it scales, when I execute 'Rotate' it scales, when I click 'Move' it scales. Hope this is somewhat understandable...
Any ideas?


text:
How can I access the Layer Enum of an image datablock in Python?
In Blender 2.79 I'm trying to access the different layers which are present in my MultilayerEXR files using Python. Basically, in my Node Editor, I have an Image node which offers me the various layers which are present in the file:

I can call the name of the layer just fine using bpy.context.scene.node_tree.nodes.active.layer, which will output 'Base' in this example.
Now, following other examples here on this site, usually I can get the possible Enum Items using bpy.context.scene.node_tree.nodes.active.bl_rna.properties['layer'].enum_items. While this does return an Enum to me, it is always the same one: It will be <bpy_collection[1], EnumProperty.enum_items> in all cases. Calling the following:
bpy.context.scene.node_tree.nodes.active.bl_rna.properties['layer'].enum_items[0]

will always return
<bpy_struct, EnumPropertyItem("PLACEHOLDER")>

How can I retrieve the list of layers which is stored in the image?

I'd imagine the placeholder is the internal item "dummy" for a dynamic enum, which is filled once an image is selected for the node, as the layer names are within the image data.  Would need to get the layer names from the image

@batFINGER Makes sense. I was hoping that even if it was a dynamic Enum, it would be exposed in Python already. It has to be around somewhere, as it's drawn in the UI. Will follow the OpenEXR header path for a start, thanks  :)


text:
How do I use world_matrix.rotate() correctly?
I've been hammering away on my keyboard for the last few hours to get something seemingly simple done. What I want to do is further rotate an object's world matrix. So I'm grabbing the world matrix like:
x = bpy.context.object.matrix_world

Now I'd like to rotate that by an Euler angle
eAngle = Euler((0.0, 0.2, 0.0)) # rotate 0.2 radians on the Y axis

What I've tried is:
bpy.context.object.matrix_world.rotate(eAngle)  # yields a ValueError, 'must have 3x3 dimensions', even though the function description states I could use an Euler as input
bpy.context.object.matrix_world.to_3x3().rotate(eAngle)  # does nothing
x = bpy.context.object.matrix_world.to_3x3().rotate(eAngle)  # x is none, so I also cannot set that resulting value somewhere else
hammering_hard_on_the_keyboard  # feels nice, but only yields keys on the table and floor

Can someone please give me a hint on how to achieve such a rotation?

if that helps, you can obj.rotation_euler.rotate( eAngle ) or obj.rotation_quaternion.rotate( eAngle ), which impacts the world_matrix. For more complete info, see https://blender.stackexchange.com/questions/44760/rotate-objects-around-their-origin-along-a-global-axis-scripted-without-bpy-op

@lemon Trouble is, in my situation I'd really like to influence the world matrix, as a) the objects might be in an arbitrary parent-child relationship, and b) they already might have rotations on the channels. The effect I'm trying to achieve is a rotation around the world origin, no matter what transforms the objects already have.

yes, look at the answer from Jerryno above, you can obj.matrix_world = my_transform_matrix * obj.matrix_world where my_transform_matrix can be whatever you need

@lemon That linked answer works for me. I can get my angle using x = Euler((x,y,z)).to_matrix().to_4x4() and use obj.matrix_world = x * obj.matrix_world.


text:
What is the difference between bpy.context.object and bpy.context.active_object?
I recently came across this question, which has an interesting detail in the accepted answer:

Also be aware that sometimes you should be checking for
  context.active_object rather than just context.object.

I have wondered a few times already, and also searched the API docs, but could not find a clear answer on it: What is the difference between the two? Up until now, I had always thought they would yield exactly the same thing, but the given answer indicates that there are situations in which the content can differ.

I think (not certain) they will differ in the following scenario:
if you execute bpy.ops.mesh.separate() on an active object mesh in edit mode, then context.object will equal the newly separated object, not the active object currently in edit mode.


text:
Map the uv values as the color of a material
Using the material node compositor, I need to translate the x and y of the uvs of a mesh (assuming they are ranged from 0 to 1), to the red and green color value of a material.

In principle, just plugging the "UV" outlet of the "Texture Coordinate" node into the "Color" property of your shader should work. This is because, by chance, your choice of colors (red, green) matches the R, G, B order.

A more elegant and controllable way is in the node setup below. The three nodes in the middle are MixRGB nodes, using the "Mix" and "Add" blend modes. Note: the Fac: value for "Add" must be 1.0.
You may want to swap red ↔ black and green ↔ black, as currently higher X/Y values give lower red/green intensities.


text:
How to make a rigid body system a static mesh?
Is there a way to make a rigid body system a static mesh?

After you have run your rigid body simulation, you have to options for how to apply the sim to the mesh.
Your first option is to simply apply the visual transform of the object(s).
Move to the frame where the object is at the location you want to keep, then select the rigid body object and press CtrlA > "Visual Transform".
Your other option is to bake the rigid body simulation to key frames.
Select the rigid body object, then press the "Bake To Keyframes" button in the physics tab of the tool shelf. Set the range of frames you want, leave the "Frame Step" at 1, then press the OK button.

uncheck "dynamic" or make it passive in rigid body's properties.

will you please add more to this answer. As it is it will probably be deleted.

@David i need a more detailed question to do that :)


text:
Uneven movement on camera following a path.
I render a short movie. I set the camera to the circle curve to make it fly in circle. The problem is after render, the camera is a little shaky. Can anyone help me? Thanks first.

could you upload your blendfile?

Did you you make a camera follow a curve with the Ctrl + P (Follow Curve) option  or you used the "Follow path" constraint?
Please check it out: http://blender.stackexchange.com/questions/23675/how-to-make-a-follow-curve-animation-more-harmonious May be helpful.

I uploaded it. You can check it now https://www.dropbox.com/sh/sa5u5wacqbum6y1/AAD3EAay8MpDKiJj8z-T0kMYa?dl=0


text:
Alt-click is not selecting edge loops on a mac.
I'm using right click but no joy.
It used to work but something has changed and I can't figure out what.

This could be related to this bug report that was posted: https://developer.blender.org/T45450

@cegaton "Alt-click is not selecting edge loops why?" is a question relating to a Linux user and the proposed solution is not applicable in my case.

Does it work if you revert to factory settings? (File > Revert to factory settings)

I had right click stop working for me on OSX. Has it stopped working completely for any selection, or just for edge loops?

I found two ways to do this
You need to go to edit > preference under the Input. turn off emulate 3 button mouse.
or
You need to go to edit > preference under the Keymap search for Loop Select and change it from Ctrl + LMB  to Shift + LMB


text:
How do I move bones from one armature to another armature in the outliner?

I would like to make sure all these bones are in a single armature so I can select them all in edit mode.
Thanks

@gandalf3, I think marking this as a duplicate of the other question is a mistake because of significant differences between this question, and the one nominated as a duplicate. That question asked merely about joining multiple armatures into one. This question specifically asks about doing so using the outliner editor window. I'm voting to reopen the question.

In the case of using the outliner, the first object can be selected in the outliner editor window by left clicking on the object. The second (and subsequent) objects can be selected by right-clicking on the object, and choosing "select" from the context menu, and pressing the space bar, searching for "join", and selecting that from the context menu..

@brasshat Hm.. Wasn't sure if the OP specifically wanted to do this from the outliner and only from the outliner, as they only referenced it in the title. If the OP does want an outliner-specific answer, then this question can be always re-opened


text:
Why my active rigid bodies are vibrating Continuously?
I am making a simulation where dominoes are pushing each others,So I made it with rigid body , when I made my dominoes an active rigid body object and played the animation all of the dominoes vibrate from right to left which cause some dominoes to fall before its pushed by the other.
This is the properties of all of the dominoes :

How can I prevent the Dominoes from moving until its pushed by the other ?
...

For your domino objects, try checking "Enable Deactivation" under "Rigid Body Dynamics" (visible in your first screenshot).

Are the dominos and/or floor scaled? If so, try Apply Scale on each - extreme scaling can affect the stability of the simulation. Also, try activatig the Collision Margin set to a suitably low value (to avoid noticeable gaps - but not too low) - this can also help significantly.

One factor that can considerably affect the Rigid Body behaviour and stability is the Scale of the objects in the scene. Where possibly you should always Apply Scale on each of the objects after you have rescaled them. This will also ensure that it behaves appropriate to its actual size rather than it's pre-scaled size and weight.
In addition, you can drastically improve the stability of the rigid body simulation by increasing the number of Iterations on the Rigid Body properties panel.

The default value is 10 and this is fine for crude simulations. Higher values provide more accurate simulations  but will take longer to simulate. Increase the number of iterations until the simulation is stable. I created a test scene with a single domino and found that increasing Iterations to 500 was plenty enough to avoid jittering without significantly affecting the simulation time.


text:
All new objects white in 3d View
I am constructing a view of some rooms of my flat with Blender 2.79 using the default Blender Render. I am not using any textures so far. Since some time, all new objects in this Blender file render as white in the 3d Viewport when using texture viewport shading (Alt Z). The image shows how a new cylinder is displayed (after adding it with Shift A):

This effect does not happen for new Blender documents, just for this file. I have checked all settings, and I don't know what can be the cause. As the Blender document format is binary only, there is no way to peek into it and see what might be the cause.
Any suggestions how to fix this problem?

How are your objects textured? What materials do they have? What render engine are you using? Under what Blender version? How did you setup your scene? Please edit your question and provide all relevant details, as it stands it is impossible to answer your question

are you using GLSL? do you have any lights?

Default light, shading is at multitexture, not GLSL.


text:
How to distribute an object to a hexagonal grid?
I want to create a hexagonal Array (in other name: honeycomb) of this object:

It is very important: I don't want to "join" the distributed objects, I want to leave them as dynamic as possible (so I prefer modifier-like solutions), but I also want blender to treat them as one mesh-object, just like the Array-modifier would do, when I click on the merge checkbox. So when I add a Subdivision-modifier to my object it will look like this:

NOTE:
The sample object I provided here is a simplified object of the one I'm going to use for this purpose: so the Wireframe-modifier and the Skin-modifier is not an option in my case. Also distributing with a hexagonal grid particle system or duplicate object to vertices of a parent object are not options, since the "final" object won't be "merged" as a single one.
Thanks in advance!

2000th question!

There is an even easier/faster solution than the one @CharlesL provided (Although some steps are identical) :

Create only 4/6 of the "cell" by using an Array-modifier and an Empty-object rotated by 60°:

Then add another Array and distribute objects on the x direction by the Relative Offset:

And last but not least, add another Array and distribute the result of the previous modifier on the y direction by the Relative Offset 1:

Of course the merge option checked in all three of the Array-modifiers.
And the result is a lighter and better version of the hexagonal array creation, plus, the result has more beautiful "edges".

the holes do not seem to be perfectly circular.

Given the shape that you have pictured above, you can do this fairly easily with a couple of array modifiers.

Start by creating a sing "cell" of the grid by adding an array modifier to the object. Uncheck Relative Offset and check Object Offset. Create an empty and rotate and use it for the Object Offset. Rotate the empty 60° (make sure that the object's origin is in the same position as the empty):

Array Modifier Setup

Result
Check the Merge option and change the distance until all the vertices merge.

Add another array modifier, and using either Relative Offset or another empty (with Object Offset), position it at the top left corner of the original object. Set the count to 2 and set the Merge options as before:

Modifier settings

Result
Add two more array modifiers to create the grid along the X and Y axis.

Modifier settings

Result


text:
Rigging a surface for game engine
Let's say I have a surface, which is divided as follows:
  A   B   C   D
0 +---+---+---+
  |   |   |   |
1 +---+---+---+
  |   |   |   |
2 +---+---+---+
  |   |   |   |
3 +---+---+---+

This surface also have a subdivision-surface modifier added to it, with level 3.
What I want to achieve is, when I grab each of the above points, the other points should "react" along with it as well.
So for example: if I grab A:0 my grab will also effect its closest neighbors: B:0, B:1 and A:1 as well. Now, here comes the hard part, which I couldn't solve because of the dependency cycles it might generate when I try it with bones: if I grab B:0 it should effect C:0, C:1, B:1, A:1 and A:0 as well. Which basically means, "for one second" B:0 becomes the parent of A:0, which of course is not possible, as I already assigned B:0 as a child of A:0.
So what I'm looking for is either a trick to have this grid like bone rig, or some other solutions (such as a 2D lattice or anything) which is available through BGE.
Thanks in advance!

I could come up with a solution to do this with bmesh, if that module is accessible from BGE? it would be able to return the indices or identifiers of those nodes, If not you could manually fill a dict which maps node-vertex to neigbours..

So you want something like proportional edit, where you can grab any vertex and the neigbouring ones move along with it as well?
To do this, simply making sure the weightings (between the bones and the mesh) extend so that some vertices are controlled by multiple bones.
So this is the weight normally:

And this is it expanded:

If you expand all of them, then, although the neighbouring bones won't actually move, there will be the right effect (As far as I understand what you want):

In this case, I could probably have expanded the area of effect some more. And, you may notice you have to move the bone further to get the deflection you want. This is because the vertices you are moving are also influenced by the surrounding 8 bones, so will not move quite so much.

you can do this with Glsl script,
or python and maybe gsl nodes,
and with bones.
if you need physics to work,
I think the only possibility is python,
(scaling and moving physics objects and deforming the graphics mesh however you feel like)

authors: алексей савченко


text:
Dynamic Paint - "Use Object material" for Brush removed in Blender 2.8?
Blender 2.79 has the option to use the material color as the brush.
Did 2.8 remove this option? Has it something to do with Blenders internal render getting removed or what's the reason?
My goal is to transfer vertex colors from one object to another, where their volumes overlap.
Transfer mesh data->Vertex Colors didn't work as cleanly as I had hoped, no matter which face corner mapping I chose.
Dynamic paint does what I want, but I can only select one color per brush object with ["Dynamic Paint"].brush_settings.paint_color

In the end I didn't use the material color, but used a small script to assign the vertex color of each object to the brush color of a dynmaic paint modifier. (Use Strg+L to link modifier to all objects)
for obj in bpy.context.collection: #use active collection
    obj_col = list(obj.data.vertex_colors['Col'].data[0].color)[:3]
    obj.modifiers['Dynamic Paint'].brush_settings.paint_color = obj_col


text:
Deactivate Info Log popup - Python: Traceback (most recent call last):
Some scripting errors generate this error popup.
Clicking the red X doesn't close the error message, but opens up Blender's Info Log.
It fades aways after a few seconds, but during that I can't click on any workspace tabs, because they are hidden behind the popup.
Is there a way to get rid of the red popup entirely? Why doesn't it just print the error message  to the console in the usual way here?

Those error messages usually appear in the middle of the bottom status bar, not the top menu bar. Have you changed Blender's UI layout at all?

My Status bar is closed. (doesn't hold relevant information for me anymore, since scene statistics moved to the viewport.)

I guess that's why the error messages are appearing in the menu bar in that case but since there are no developers here to ask...

Should be gone by deactivating Preferences > Keymap > Window > Update Reports Display

Delete the entry in:
Preferences > Keymap > Window > Update Reports Display
(as @relaxed pointed out in the comments)


text:
Read pixel color with foreach_get() on image data
I tried filling a numpy array with the foreach_get() method on an image, but get the following error:
foreach_get/set() takes exactly 1 argument (2 given)
def read_pixels(img):
    resolution = img.size[0] * img.size[1]
    colors = np.zeros(resolution*4, dtype=np.float)
    img.pixels.foreach_get("pixels", colors)
    colors = np.reshape(colors, (resolution, 4))
    return colors

img = bpy.data.images['TestImg.png']
print(read_pixels(img))

foreach_get() should take 2 arguments, doesn't it? The name of the attribute ('pixels') and the array to be filled?!

I'm not sure, but you call foreach_get method on the pixels object, so the method uses its self argument which is set automatically to the pixels object. From what I could google, other people use foreach_get by only passing the numpy array as a temporary buffer, so you should try img.pixels.foreach_get(colors)

"The python console check"
In case Markus is busy can get a lot of info using autocomplete Tab in the python console, with an image as img
>>> img.pixels.foreach_get(
foreach_get(seq)
.. method:: foreach_get(seq)
This is a function to give fast access to array data.

which is plainly different from, for instance a mesh me vertices, which asks for an attribute attr , eg for vert coordinates "co"
>>> me.vertices.foreach_get(
foreach_get(attr, seq)
.. method:: foreach_get(attr, seq)
This is a function to give fast access to attributes within a collection.

A very slight improvement in speed can be attained by using np.empty to initialize the array, since any garbage  will be filled by the foreach get.
import time
import numpy as np

REPS = 100

def time_it(func):
    def wrapper(*arg, **kw):
        t1 = time.time()
        for i in range(REPS):
            func(*arg, **kw)
        t2 = time.time()
        print(func.__name__, (t2 - t1))
    return wrapper

@time_it
def read_pixels(img):
    resolution = img.size[0] * img.size[1]
    colors = np.zeros(resolution*4, dtype=np.float32)
    img.pixels.foreach_get(colors)
    colors = np.reshape(colors, (resolution, 4))
    return colors

@time_it
def read_pixels2(img):
    x, y = img.size
    pixels = np.empty(x * y << 2, dtype=np.float32)
    img.pixels.foreach_get(pixels)
    return pixels.reshape((x, y, 4))

@time_it
def nptest1(img):
    x, y = img.size
    return np.array(img.pixels, dtype=np.float32).reshape((x, y, 4))

@time_it
def nptest2(img):
    x, y = img.size
    return np.array(img.pixels[:], dtype=np.float32).reshape((x, y, 4))

import bpy
for img in bpy.data.images:
    nptest1(img)
    nptest2(img)
    read_pixels(img)
    read_pixels2(img)
    #break

Results
nptest1 8.4240
nptest2 7.0605
read_pixels 0.2264
read_pixels2 0.2222

Note on posting noticed I had reshaped to image x, y, 4, however reshape is an almost time "free" method, will get back if otherwise.  (Got a squeak more using bitwise shift to quadruple)

as Markus von Broady pointed out, ommiting the attribute name and just passing the numpy array works. Thank you.
I was confused, because specifying the the attribute name worked in other areas, e.g.
sculpt_vertex_colors[name].data.foreach_get('color', colors)

But I guess that's a different structure.
Had to change the dtype to float32 instead of just float.
Here is the corrected example
def read_pixels(img):
    resolution = img.size[0] * img.size[1]
    colors = np.zeros(resolution*4, dtype=np.float32)
    img.pixels.foreach_get(colors)
    colors = np.reshape(colors, (resolution, 4))
    return colors

img = bpy.data.images['TestImg.png']
print(read_pixels(img))


text:
How restore the right normal-axis once for all faces?
I try to study Blender, especially in connection with the collaboration of Blender and After Effects.
My question, as it can be seemed for you, is to simple or obvious, but I can't  find answer.
So, I have some lowpoly mesh (consist of few faces). Then I split this mesh on separated faces - each face is a separated object.
I need to restore right orientation of norma axis for each face - with the normal axis coinciding with Z-axiz (perpendicular to the surface of a face).
When I create a new mesh/plane and turn on "Transform orientation" - "Normal" - Z-axis is perpendicular to the surface of this plane and X,Y-axis lie in a plane.
When I separate some lowpoly mesh on faces - I can restore a center of mass for each faces ("Origin to Geometry" once for all faces), but I can not restore a normal-axis for all separated faces - when I go to the Edit mode I see the so necessary for me right normal-axis (perpendicular to the surface), when I return to the Object mode - normal-axis has a different orientation.
How can I restore the right normal-axis once for all faces? (may be, some script needed).
Thanks.

If I understand your question correctly you want to be able to transform an object in object mode using the normal orientation of one or more faces of the object?

This is only sort of possible. The normal of an object is kept when you separate it. However, even if you have a one-faced object, blender will not allow you to move the object based on its normals, because most objects have more than one face, which means the direction of motion would be conflicting.
You can move faces by their normal in edit mode though.
Simply change the transform orientation to "normal", go in edit mode Tab and you can transform by the normals.
In the image below, I started with a sphere, and separated out a face. I then went into edit mode on that face, and changed the transform orientation to that normal. Now I can move according to that normal.

you can actually move an object in object mode based on a normal: 1. in edit mode, make a selection of what you want to use as the normal direction. 2. press ctrl alt space. 3. exit edit mode.

That's awesome! I was looking for this a little bit (because it was brought up in this question, and is an interesting topic I'd never thought of). Do you know how to select a face, and "apply" the rotation of the object to the normal of that face? That would answer his question (and be a cool fact to know). If you come up with anything, let me know. Thanks.

Ask separate questions as separate questions, please, and not in a comment thread on an answer.


text:
Extrude multiple edges with normals
I have the following problem:
I have walls with (wood) panels. I want to (extrude?) the blue edges so they look like the red marked one...
When I select all the edges and extrude & scale them, then they will also be scaled on "the wrong axis"...
I'm very new to Blender and have no idea how to do that... a keyword would propably do it, because english is not my first language and i don't quite know how to express myself...

Select your loops
Press 'Spacebar'
Type in: Extrude and Move on Indiviual Normals

While scaling, you can press x, y, or z to restrict the scaling action to only one axis. You can also press shift x, shift y, or shift z to exclude an axis from the scale action.

You should also make your normal consist and recalculate normals. While in Edit mode, select all, press Ctrl+N (will make normals consistent), Press T, for left panel, under Shading>Normals>recalculate normals


text:
How could I "re-align" grease pencil vertexes on one axis?
let's say I have this line:

How could I "re-align" vertexes on one axis so it would become a line ?
On a regular mesh, I would have set the pivot point to 3D cursor, then scale X 0; and points would have been aligned.
But with the Grease Pencil, it seems it also affect the "strength" of the vertexes, my line is loosing it :

How else could I do ?
Thanks !

Well this is strange because when I use S+0 on grease pencil, my stroke doesn't loose it's "strength"

Uncheck Stroke → Scale Thickness:

That is wonderful !  Thanks.


text:
How can I use an animated bezier curve as a boolean for a mesh?
I have a bezier curve that I have animated with an armature and hooks.
It is 2D, has a fill mode set to both, and is extruded.

Now, I want to use that curve to make a diff operation with a mesh.  Is that possible and how ?
Eventually, I might need to convert the curve to a mesh but how to do this since it is animated ?  Thanks !
Thanks !

Export as Alembic, import back and add Boolean modifier ...?

Holy shit, it works !!! Thanks a lot !!!

Great it works for you ... just a note - this format is a sequence of vertex positions (can be exported fluid sim or what ever) ... vertex on one frame is not the same on another frame ... it means this format can't handle UVmaps.

Export as Alembic, import back and add Boolean modifier ...

Here example ... curve Full, Depth, Extrude ... animated with two Shape Keys

Export as Alembic ... under export Options check Curve to Mesh.
Import Alembic back ... it comes as object with modifier Mesh Sequence Cache.

Now you can add some object for boolean operation (here Cube) ... select your imported .abc object and add Boolean modifier.


text:
Navigation mesh not found in properties
I have been following a Blender book which asks me to build a navigation mesh (Properties > Scene > Build navigation mesh) but I am unable to find it in my installation. The version the author of the book is using is 2.6.3 and I am using 2.74 that is probably why. Is there any alternative to building a navigation mesh, or has the option been shifted elsewhere?

Hi Saurabh, I'm sorry but I don't know what is a "navigation mesh". What is the purpose of the chapter you're reading in the book? Which book is it? Please elaborate a bit your question (click the edit button above) so we can figure out what exactly is the matter.

You must enable the blender game engine, there you will find the navigation mesh


text:
Making an Invisible Material in the Cycles render engine
I'm a newcomer to Blender and have created a scene in which I want to animate the disappearance of an object. I don't know if this is the 'right' way to do this, but I managed to get the desired effect by having a big block move over the object to be disappeared, and I added a boolean Difference modifier to the object to be disappeared.
This gets me the effect that I want, but I haven't been able to get my big block 100% transparent. It's almost, but not quite, entirely unlike a solid object, but it still casts a shadow and appears to have other visual effects on the animation that I don't fully understand.
Can anyone hand-hold me through creating an absolutely invisible material for my big block, or teach me the 'correct' way to accomplish my goals?
Thanks!

What is the purpose of using the big block? Is because you need a particular fade-out transition? What is it? Anyway a simple transparent shader set to full white color (by default is 90%white) should be completly invisible.

Possible related questions: http://blender.stackexchange.com/questions/30458/how-to-make-text-fade-in-and-out and http://blender.stackexchange.com/questions/35734/how-to-animate-text-being-revealed-on-the-screen/35740#35740

Possible duplicate: http://blender.stackexchange.com/q/5113/599

If you want the object to disappear gradually I would do it with the material.  To make it disappear from top to bottom/side to side etc. (like a box covering it up as you described) I would se this node setup for it's material.

You can then animate the value on the greater than node (the one in yellow) from 1 to 0 to make the object disappear from top to bottom.  If you want left to right use the X value from the separate XYZ node.

This works because taking the X, Y, or Z component of the generated texture coordinates gives a gradient from 0 to 1 from left to right, front to back, or back to front respectively.  The output of this, sent through a greater than node to chop it off at a certain point, is used to drive a mix shader mixing the normal material (in this case the diffuse shader) with a transparent shader.  When you animate the value of the greater than node you are animating the cutoff point.

I can only think of a work-around, in the materials tab (on the right) set the node to mix shader.
Add a transparent shader to each one. I'm presuming this works by making it at 50% of it's transparency, then adding a second one makes the transparency 0%


text:
rendering: is a transparent material equivalent to a non-existent part?
I would like to know if assigning a white transparent material on some parts of a mesh is equal to deleting thoses faces from the mesh; regarding the rendering times ?
I like to keep faces on my meshs and assigning a transparent material on it since it allows me to still be able to select edge loops, etc.
But I don't know it this is a good technique.
Thanks for your advices !

No, an "alphaed out area" is not the same as deleting those polygons.
In any raytracer (such as Cycles or Evee), a ray is cast (either from the light source into the camera or from the camera to the light source, I do believe, but somebody else can tell me if it's wrong, that in Blender we do the latter).
If this ray now has to go through one of these holes:
a.) If its cut out, it just goes through
b.) If its alpha, the ray hits the mesh, looks up the material, looks up the uv unwrapping, then decides that it has nothing to show and travels on with its path.
This said, adding a lot of more polygons to accomodate for the holes, will affect your blender file's size and the RAM usage.
There is no better or worse, its "case sensitive". For making trees, e.g. , some tutorials suggest to not use alphas, but cut the leave's plane to the mapped leaf texture (because then you could have ray intersecting hundres of leaves, but only in its alpha regions and slowing it down unneccessary).


text:
Geometry Nodes & Viewer node : how can I debug a value?
i'm learning Geometry Nodes and I'm trying to catch the value of a node to debug it.
I think this should be achieved with the Viewer node, which has two inputs : Geometry & Value.
Connecting a mesh to the geometry input give me a feedback in the spreadsheet, as expected :

Now, I would like to inspect a value, but I don't see where the data gets rendered:

Can someone explain ?
Thanks !

The value sockets are divided on two types in GN, field and singular ones. More about that here: Why node socket shape is different (diamond vs circle)?
Field values
The value without geometry doesn't make sense. If you connect a random value node to some geometry, you will get a random value for each item in the set:

To make it clear, let's look at this setup:

Here, as you can see a plane with 4 points is created, and each of 4 points is moved in z direction at random value. Then the plane is subdivided 4 times and each of the resulted point is moved at random value, forming a noise pattern.
I think you expect to see 2 different random generators for each step. But it's not necessary, because random generates values for geometry plugged in.
So if you try to debug first step, you should do this like this:

4 values generated.
And for second step:

289 values.
Another example is then you add this random value to some point position:

If you don't connect this to some geometry, where Blender should get positions of vertices?
Singular values
But what about singular values? We need to note, that Random value node by default is not a singular one. To make it singular, we need to plug in a singular value in the ID value, so then it will be used as singular value (round socket) Geometry Nodes: How to use the Random Value node? (Output is red) :

So to debug singular values (round socket) you don't need a special node. Just hover mouse over the socket to preview its value:

but the node should be connected somehow to output to be calculated:

"The value without geometry doesn't make sense." - well, why ? It might help me debug my setup and understand what values some nodes do output.

In Geometry Nodes all values are in the context of a geometry. You could do some static calculation and bind it to the output node. But there would be no reason to use Geometry Nodes for that.

@gordie I've updated answer.

you can always have a 'Value to String' and a 'String to Curves' pair of nodes, maybe group them with a Set Position or Transform node and call it INFO or something... I've used this quite a few times

Thanks for this amazing answer.  But I don't see how it cannot be useful to get feedback on some computed values (eg. math operations), like Animation Nodes did

see here ?

@gordie ok, I've missed some important part. I've updated answer

that's amazing :) Thanks a lot !!!

(...that's too bad that the node should be connect to output to calculate the value)


text:
How can I connect the top loop to the down loop with faces

Hey I want to connect the bottom loop with the top loop so that it forms a solid.
I have tried selecting multiple vertices and pressing F but that just creates a large face which I do not want.
I have tried using grid fill bu that doesn't work either.
The solution that seems to work is by selecting four vertices and pressing F and then selecting the next 4 and pressing F and on and on. That just takes too long.

You should use Bridge edge loops command:

Select both loops:

2.Then click space and type bridge edge loops:

Click on it and its done:


text:
Collision/Rigid body objects not moving an inch
I'm trying to make arrows fall onto a table, in order to dispose of them on the table randomly. So I enable collision/rigid body on the table, passive mode, and add collision/rigid body on an arrow, active mode. But when I hit alt+a, nothing's happening, and the arrow won't move an inch. I don't remember having to use anything more to get it to work, but surely I'm doing something wrong ? What I am missing please ? Thank you for your help

Scale problem. Since I also used Blender for 3d printing (with scale unit configured at 0.01), all my 3d objects use this scale, and it seems to affect rigid body behavior. I was able to get around the issue switching back to 1 scale unit. It's still not working properly but it's sufficient as for now.

FYI, unable to reproduce the problem here, with a simple setting and the same unit at 0.01

Ah, that's because I didn't explain properly. I usually use 0.01 unit scale and my startup script is setup with it , but since this project was different, I changed it along the way as I was modeling. That was not a good idea since I think I messed up some things (for example, I need now to switch to 10 scale unit in order to see the grid in the scene). Long story short : it's a setup issue on my end, and until I figure what I'm doing wrong, I don't think anyone could help me. At this point, only sharing the blend could help me I suppose. Anyway, thank you a lot for trying.

An old question but as it's the top search result...
There may be some Passive items stopping the Sim, remove items that won't interact with anything important from the Rigid Body.
I'd added nearly everything as Passive with its default Convex Hull, which was excessive in my simple case of dropping rocks into a pile.
Using 2.8 and got this issue.

3.0 here and ran into the issue as well. Turns out however, that in my case I just had to start playback from frame 1 once. That may sound obvious to many, but it wasn't for me, and took me a while to figure out.


text:
Scene always rendering cube
I am not that proficient in Blender, and this has me baffled. I have it set to Cycles Render and I am using a single material that is Cycles also.
I have a scene when the view port shading is set to rendered looks like this:

but this is what is rendered:

this is my outliner:
I had to add the outliner to the first image because you need 10 reputation points. really??
Any help would be appreciated.

In future, if you need to add more images than SE will allow then you can upload using an external service (e.g. Imgur), add the link to your question and someone with more reputation will insert the image for you.

Look at your outliner, see the 'template' object at the bottom?  You have set that object to be rendered (camera icon) but you have hidden in it in the viewport (eyeball is greyed out).  So it is appearing in your renders -- you want to hide its render visibility (by clicking the camera icon) so it is greyed out. That or just delete the entire object.

I feel like a buffoon! Thank you for the help!

@MichaelWRiemerJr don't forget to mark the answer as accepted. :-) (It will give you some reputation)


text:
Help with baking results in cycles
I am a software engineer struggling with getting good in Blender. Currently I am trying to get better at baking, specifically in cycles. These are some screen shots from inside unreal engine. I have re-UVunwrapped this model a few times trying to get better results, and played with smoothing and seams. I also tried to correct some smoothing issues, things that look like glares across the model. I am wondering if these poor results are a result of UVunwrapping, Baking, the seams, or smoothing. Here is a link to the Blend file https://1drv.ms/u/s!Alrv4w-MciWDkY16VX5XIhvgJYUrpw

Thanks in advance

You are baking the normals form a high poly model, but it's not totally aligned with the low poly model.

You can see how the dark areas produced by the normals are where the high and the low poly models don't match.


text:
Object displacement in BGE
I have an object created in Cycles. After switching to BGE some parts(bandwrist elements) are significantly changing its position, though in viewport everything is correctly displayed.
In other threads it is said that problem can be related to broken modifiers, but in this file I've found modifiers that only affect shape of bandwrist elements and after disabling them, displacement still being there anyways.
Blend file : http://www.filedropper.com/wristwatch

Actually just remove parenting of every object.


text:
How to make this face look more voluminous, round and friendly?
i´ve created a lion humanoid with blender, but the face did not yet get the look i wanted it to have:

i have found a picture of a model in the internet with the right looks:

is there an easy way to make my model look more like the other one, by using some modifiers or doing something?
(ignore the errors at the eyes, i allready fixed them)

There is no magic modifier to make your model look like some picture from the internet. You'll have to model or sculpt it according to your reference image. That can be very easy or very hard to do, depending on your skill level.

i didnt ever want to copy the picture i found in the internet
it just helped me to tell u what i direction i wanna go with the mouth


text:
Blender 2.77 crashes on startup, graphic problem
I have a problem with Blender 2.77.
It crashes on startup with no error message.
I found this problem of graphic settings but I don't really know how to fix this.
Something with my CPU maybe? Got the good drivers I think.
I installed Blender with the installer first (same crash) and now i got the ZIP version.
I got a MSI with: Windows 7 Ultimate 64bit / CPU: i7-4810MQ / GPU: GTx870M

If you guys can help me, it would be awsome! Thanks.

Try the new 2.77a - maybe it's already fixed? Else this is a bug which should be reported and not asked here...

Maybe related: http://blender.stackexchange.com/a/46769/2843


text:
GPU final render is very dark (depending on number samples)
Not sure what happend - GPU rendering worked fine before - but now I cannot get blender to GPU render, though rendered preview works(!), so it shouldn't be driver. I have an AMD card, cannot remember driver updates recently. Updated to latest after the issue happend and it didn't help.
Problem is not related to file - same thing in the new projects now.
Also it depends on the number of samples, below are the render results for 1, 2 and 3 samples respectively. On 50 samples it's like almost completely black.

Did anybody had similar issue? Is there a known solution?

How does it work on CPU ? Did you try checking if there is a setting that differs between preview and final render and isn't supported on AMD GPU ?

It works on CPU (slow as hell, but seems like I don't have a choise now). It worked previously (like a week ago), so everything should be supported. I didn't change my PC configuration or anything - it just happend some day...

Ok, so I found (thanks to Mr Zak!) that one of the differences between preview and final render was a Motion Blur. Even though it is disabled in preview and I had it disabled in render settings, when I enabled it in render panel and everything works again!
Though I definately remember it working from default blender file (where I suppose it was disabled?)... and this is seems like a bug, but hey, we found a workaround!


text:
Blender 2.77 renders smoke\fire domain solid black on GPU (Cycles)
I have just updated to 2.77 version and was very exited about using GPU for rendering fire.
When I tried to render the test scene I got this:

Though it should look like this (rendered on CPU):

Blender is rendering domain solid black for some reason.
I got the following configuration:
AMD Radeon R280x (3Gb)
OpenCL Version
2.0.4.0

AMD Cards might still have some driver issues and are not fully supported yet as fas as I know...

At the time of writing, smoke/fire is still currently only supported on CUDA/Nvidia cards.

I asked a question on 2.77 smoke and fire recently, too, that related to your answer on a python script to bake smoke. I use that script, but it stopped working when I upgraded to 2.77. Could you please look at my question here: http://blender.stackexchange.com/questions/49591/2-77-headless-smoke-baking Thanks in advance.

I have noticed a bug i think , i have a gpu cuda nvidia card, and the render with smoke/fire works fine, IF i only have one smoke domain in the scene, if I add 2 or three they wont render, only the first one. switch to cpu and all render.


text:
Can´t bake larger textures than 1000x1000px
I have a problem with baking textures in cycles. No matter what image size I create for UV coordinates, the baked image allways shrinks to 1000x1000 px, thus gets pixelated.
Do you have any ideas, why is it happening and how could I solve it?

How are you creating the image, and are you sure it is baking to the same image you want?

UV Coordinates do not determine the pixel by pixel dimension size of the image.  Your specification of dimension at image creation time does this.

I have this high-poly model. after unwrapping it with Smart UV Project I created New Image and set it to be 2000x2000 (example)--
http://postimg.org/image/4miw72uwj/
before baking, the image had this size in UV/Image Editor--
http://postimg.org/image/mdq0dcl2r/
immediately after baking it shrunk (it was not me scrolling away)--
http://postimg.org/image/w8acrr1l3/
when I opened the image in Photoshop, it shows its real dimensions and quality. now it´s 1024x1012px and really pixelated--
http://postimg.org/image/5nhzk8l3t/
thank you for you answers :)

Did you remember to select your image in the node-editor while baking?

Did you set the image texture in your material node setup to the new larger image file?

I did bake a cube to a 3k by 3k texture without problem.

oh thank you sooo much! I didn´t get the thing about linking new image texture to the newly created image. you´re the best, best wishes
Wrawraww

It kind of got answered in the comments by  DrRiisTab. I just tried to create a nice answer out of it :)

If this answer helped you please consider marking it as correct or at least up voting


text:
How to create tilable tile-map elements
I want to create an isometric game, and therefore I want to use blender to create tile-map elements which I will compose together with Tiled Map Editor later on. I have followed several tutorials describing the camera settings. My setup looks like this:

You can clearly see that the cube is perfectly aligned within the camera. Even when maximizing zoom inside the 3d view, it does not miss a pixel.
Rendering this with cycles (128x18, hdr lightning, transparent background, png zero compression) gives me the following:

Doesn't look that bad, right? Well If I now open Tiled, creating a map with a Tile Size of 128x64 and use the image from before as 128x128 tile, I get the following result

One can clearly see the thin border around every tile. This is my problem. How can I prevent this from happening? Of course this is reproducible when concatenating images with paint, thus I have to resolve it either with blender or something in between blender and the map creation.
My guess is that it has to do with the anti-aliasing. When zooming in, due to the nature of anti-aliasing, some pixels are semi transparent.
Of course One could change the camera scale or the object size to counter that, but this will cause further issues as other edges are overlapping their "boundaries" then causing weird artifacts. Of course, I could increase size and then cut away the outer pixels with an exact mask, but doing so this starts to get really complicated.... Isn't there a better way?

Using the 'Box' filtering method seems to fix the problem :

If that don't work well for you (ie, because the Box filtering isn't as nice looking), you can try something less practical...
Render in x4 resolution (512x512), without anti-aliasing, then reduce the image size with Gimp* or whatever :

I tried with Gimp, but I'm pretty sure ImageMagick will give you similar results, with the advantage that you'll can greatly automatize the process.

Well, that's more or less my answer which I linked above.

I don't think so ; yours don't explain how to get an actual anti-aliasing that fix the problem. However, you explain way better what happens and why it happens :)

No, of course I don't explain how to get anti-aliasing, because anti-aliasing on the transparent background will always result in the edge being partly transparent, which will create a visible seam which is the actual problem in the question.

Of course. The question seemed to focus on Left and Right border, and my answer address that particular problem ; I just realized that didn't fix the 'oblique' borders.

The only problem is, my answer was originally for Eevee where you can set the Filter Size to 0 (manually, but the slider will stop at 0.01) which is not possible in Cycles. So it will never be perfect without tweaking it. You could manually adjust the Alpha to only have 0 or 1, but instead of being semi-transparent on the edge it would then be semi-black which isn't really better.


text:
Missing 'rect' attribute in RenderLayer
According to this simple external renderer, result can be generated in the memory instead of loading from an external file.
    # In this example, we fill the full renders with a flat blue color.
    def render_scene(self, scene):
    pixel_count = self.size_x * self.size_y

    # The framebuffer is defined as a list of pixels, each pixel
    # itself being a list of R,G,B,A values
    blue_rect = [[0.0, 0.0, 1.0, 1.0]] * pixel_count

    # Here we write the pixel values to the RenderResult
    result = self.begin_result(0, 0, self.size_x, self.size_y)
    layer = result.layers[0]
    layer.rect = blue_rect
    self.end_result(result)

I got an missing 'rect' attribute error from Blender 2.75.
Here is the error
layer.rect = blue_rect
AttributeError: 'RenderLayer' object has no attribute 'rect'

The 'rect' attribute was still there in 2.67.1 version blender, is it deprecated in the latest version?
How should I update partial intermediate result in Blender? The only solution that I can find is to update the full image with "load_from_file" function which takes a filename parameter and loads the data from file system.

Use layer.passes[0].rect = blue_rect instead of layer.rect in your code.