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Exporting bones; transformation of quaternions necessary?
I'm writing a small addon to export armatures and actions to an in-house rendering engine. The rendering engine uses a traditional OpenGL-style coordinate system, with +Y representing UP and -Z representing FORWARD.
Bones in the in-house system store a location, rotation (quaternion), and scale, so I'm exporting to this representation directly. In the addon, I'm using Blender's standard axis conversion functions to transform positions to the target coordinate system. However, my mathematical understanding of quaternions is somewhat weak and I'm not entirely sure if I need to be transforming quaternions too.
While I understand that quaternions do not have "handedness" or anything like that, I do feel that, for example, a quaternion that represents a rotation around the Z axis in Blender probably needs to be transformed so that it represents a rotation around the +Y axis in the target engine. Does this seem correct?
If some sort of transformation does need to occur, is there anything already in the standard API to facilitate this? I'm unable to find anything (possibly because it's not there, possibly because the transformation isn't actually necessary!).

The answer is yes: The quaternions do need to be transformed. If a quaternion represents a rotation around an axis in the source coordinate space, then it's inevitably not going to represent a rotation around the "same" axis in the target coordinate space if it isn't transformed.
As to how to do this in Blender:

Convert the quaternion to an axis/angle representation using the built-in API functions.
Transform the axis using the standard axis conversion functions that are supplied for vectors.
Convert the transformed axis/angle back to a quaternion using the built-in API functions.


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tissue addon how to create pattern on sphere
Hi I am trying to add a a cylinder pattern on the faces of the icosphere.(image 1)
Image 1:

thought tissue addon might work but can't get the pattern to sit correctly on sphere (it gets squashed see image 2)
Image 2:

However I have tried individually extruding the faces of the icosphere, then scaling down, subdividing edges... but can't find a way of making each one of those faces circular (so I can extrude then all out to make the cylinder parts jut out).
In reponse to answer..This is happening ..what am I doing wrong?First Image below

It should be achievable with Tissue add-on.

Make sure the normal's of your objects are correctly ponting outward. In your image they are not in the component object (you can see it from the dark blue tint of the faces). I'll suggest to check the orientation by enabling the Normals checkbox in the Mesh Display Panel. But that's not what prevents you from obtaining a good result.
From your images it seems that the adaptative geometry is collapsed on the Z-axis. Try to keep the value away from the 0, and also check the rotation of the component: the add-on is expecting a shape developing on the Global Z axis.
Dont' forget to pick the objects in the correct order and leave Quad mode in the settings.

Note that as tris based adaptation is currently not supported, you'll encounter some deformation on the cylinder. A possible alternative that would not led you to a component distortion could be Duplifaces:

You should perform a "smart" remove doubles in order to get rid of the spaces between the duplicated component (Dupliface it's not adaptative as Tessellate is).

About your last pick, I may guess your component has some loose geomerty that is altering the overall boundary. As all the geometry is taken into account, the space beteween the componeent and the vertex, will be reproduced too.

i have tried it but it is only covering parts of the sphere with geometry.photos on edited post

Probably your component object has some "flying" geometry, like a lonley vertex somewhere, that alter the overall bounding box and lead to the wrong result. Give it a check. If you can0t find it, I would suggest to upload your testfile to http://blend-exchange.giantcowfilms.com/.

I have same problem i have posted the question https://blender.stackexchange.com/questions/94292/how-to-make-tissue-of-the-mesh

I'm the developer of Tissue. In order to create a symmetrical cylinder I suggest to use FAN mode, using instead of the full plane+cylinder component, just a third of it, like a single petal.

Anyway, it will not be perfectly cylindrical.
Alessandro

source: Stack Exchange

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

sort: votes


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Can I delete org.blenderfoundation.blender files? / clear space on hard drive
I'm very low on ssd space and DaisyDisk says 357,4 GB are occupied with org.blenderfoundation.blender files.
Can I just delete these? These are not actually System files, maybe its something blender creates temporarily? Because some of them are from 3 years back.
Because what could go wrong? In worst case just reinstall Blender.
Any. help would be appreciated as I have no other option where to free up more ssd space.
Thanks!

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


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Blender freezes when rendering,building the last samples
Out of sudden the Blender freezes when rendering on Cycles.Always at the same moment.When the image is almost done,that is to say Path tracing title is done 135/135 and it's building up samples,at the last point it stops working.I made all the updates to mac OS and using the last 2.78a version,even though it started on 2.77
I thought it was the project's problem so I opened different project and it does the same thing.I'm completely stuck and unable to render anything.Sometimes it renders one frame but the following gets stuck again.
Is anyone else experiencing this? I have no idea what it could be?
Thanks so much for any help.

Halo Cegaton,thank you for quick reply.I'm rendering on CPU with the normal texture size,some 1024x1024,some 2048x2048.the image is full hd 1920x1080.I'm rendering to  PNG frames but when I switch to other outputs like Tiff,Jpeg or QT it does the same thing.No simulations.no particles involved. Plus I have already rendered like 2 minutes of this project. I thought that it's the project's problem,maybe I clicked on something without knowing,but when I open any other project it does the same thing.Even when I only have a textured cube with simple animation it still freezes.I'm really lost here.

Have you ever found a solution to this? Im suddenly experiencing the same. I can't render Files  anymore that rendered fine dozens of times just hours ago...

For laptop users:
On any render, my computer (the whole screen) would freeze about 5 seconds, and after some seconds it would freeze again.
To fix, I had to go to File -> User Preferences -> System and on the bottom-left side I picked CUDA for the "Cycles Compute Device", and this fixed the problem.

It seems very noob-ish because it actually is! And it worked for me since I am a beginner, I hope this helps another beginner searching this on Google.

See this answer https://blender.stackexchange.com/questions/7485/enabling-gpu-rendering-for-cycles and this one for more https://blender.stackexchange.com/questions/65871/why-is-blender-just-using-54-of-my-cpu-when-rendering-in-cycles

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

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


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Blender 2.80 does not preview in viewport/render textures when in Cycles
Halo, I upgraded to 2.80 and I have problem seeing the textures in rendered mode when in Cycles. All works fine in Eevee.Same happens when i try to render the image.
All good in Eevee but outputs grey screen when in Cycles.Same happens in CPU/GPU render. I have the latest build installed. It only happens in this Collection/Layer.
In other Collections it all works fine. I have no idea if Im doing anything wrong, or it this could be some Beta bug? Would anybody know, thanks you for any help.
https://www.youtube.com/watch?v=e0ND0B7ZCyc&feature=youtu.be

I had this problem with earlier releases of the Beta. are you using the latest version? They release new builds of the beta daily. It's entirely possible the bug is fixed in a release a day or a week later, as it was for me

Hi,thanks for your reply. Yes,im on the latest build from 12.6.  I am downloading always the latest version hoping it would fix but nothing. It strange it only afects one Collection. So yours got fixed just by installing a new version?

Yeah, a month ago I was on here saying my models were getting weird artifacts in the realtime render view and then finally it was just the artifacts. But maybe 2 weeks later I downloaded another release where the same file could be viewed bug-free in that mode (I did send the Unity devs an official bug report before then, though)

ok, so I guess I'm not doing anything wrong, it just might be a bug. Will wait out till the oficial release then, lets see if it works.Thank you!


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How to scale vertices uniformly in one direction?
I want to scale a set of vertices off the center and towards a point.
Here's the current setup :

I want to scale the selected vertices equally towards the edge of the wing. Scaling in X axis isn't working.
What's the correct method here ?

Pivot is the origin, not the goal.
The pivot point is considered the origin of the transformation space. Scaling the objects with a factor smaller than 1 will make them collapse toward the origin, while what you would like to achieve is verteices spreaded from the origin toward another point. The scaling factor should be greater than 1 in this case (e.g. the double, the triple...).
I suggest to change the position of the 3D cursor to the symmetry axis instead of the goal point. This way you'll be able to scale your vertices uniformly, even if they are not evenly spaced.

To do that, first steps :

1 : set pivot to median point for now
2 : enable proportional editing
3 : set it to linear

Now hit S but dont validate it
This is just a way to tune the proportional editing so that it bounds the points you want to scale
Use the mouse wheel or PgUp and PgDown or plus the Shift key to tune it more precisely
Once done, hit Esc as we don't want to move anything for now

Set the pivot point to 3D cursor (indicated by 1 below)
And hit Scale+X+0

But to tell the truth, I am not sure this is the result you want. You may have to try with several proportional editing modes (sharp, root, sphere, smooth...) to see what is the best for you.
If needed, you may also hide the vertices you don't want to move so that the proportional size can be tuned without affecting the unwanted vertices (to hide select them and H ; to unhide Alt+H)

You can use the LoopTools Addon for this task.
1) snap the last vertex of your plane to the desired destination location:

2) select the loop which you plan to space out evenly

3) click the 'space' function of the LoopTools Addon


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Is it possible to render a single game engine frame in cycles?
I'm looking to use the blender game engine to get my frame to a certain point, stop there and then render that single frame in cycles since cycles does a much better job of rendering for certain aspects of images.  How might I do this?

Cycles and BGE are two completely separate and independent entities aside from both running inside Blender. It might be technically be possible to extract camera position from a running game and through scripting pass it onto Blender to render another scene, but you would need some serious scripting to accomplish this and would never be able to do it from a standalone game since it would not include the Blender and Cycles binaries required for operation. You also need to set up a separate scene with proper materials to render from Cycles and it might take a considerable time to render.

Are you perhaps trying to bake physics? There are ways of doing this. Otherwise, you could write a python script that stores object positions/rotations so that you can load them in blender later.

I found the solution to my problem.  I end up running the 'render game engine' while having the 'record animation' checkbox checked under the Game dropdown.  Of course, you need to change to the 'Blender Game' rendering before this otherwise it won't appear.  Then starting the 'Game Engine' by clicking 'Start Game Engine', as it is recording, all of the keyframes are created  Once I find the frame I want that represents a good image of what I wish to render.  I move to that frame and turn it over to cycles render.  Here I can play with the materials, lighting, etc in order to get just the right image to be rendered.

Wouldn't it just be easier to use Shift + F to move the camera in first-person game style?

I'm looking to have my final render done in Cycles Render.  I'm not sure I'm understanding how your solution would help unless I'm missing something.

You seem to be using the game engine solely for the purpose of positioning your camera. You can position your camera where desired directly from the Blender viewport by pressing Shift + F while in camera. This will enter "Fly Mode" or "First Person View mode" and and then you can render it using whatever you want, Cycles or otherwise.

I'm using the game engine for the physics so I can let the physics do their part.  Then I find a frame that fits best and then switch over to cycles.

Oh, OK, never mind then, I thought you just wanted to use first person view to place the camera.


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How can I automatically render a preview when the scene has changed?
I have a split screen with my render on the right on very low sample rate so the render will happen quite quickly.  On the left, I have my 3d camera perspective for my modeling and object manipulation.  What I would like is to have the right side update the render when my objects on the left are changed automatically.  Is there a setting for this?  I already have the Update Automatically checked under the view menu however it doesn't seem to affect anything.  Thanks for your help.

Just do the preview render in the viewport itself and set the viewport shading to "Rendered". Also type Numpad-0 to set the view and check "Border" to render only the important parts.
Everything you edit on the left side will cause the right screen to re-render.


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How can I move an object along it's local axis?
I'm looking to move an object, just when I edit it, along its own axis rather than the world's axis.  Is this possible?  Also is origin synonymous with axis?

It is preferred to only ask one question at a time, you can ask as many as you want. An axis is part of the coordinate system used to define locations in 3D space. The origin is the centre of that system. In 3D graphics, "object origin" is often used and refers to the object's location in space, which is the zero point used for the (mesh) data for that object.

I can thing of two ways:
1) In the 3D view Editor header you can choose the transform orientation
2) lets say you want to move in in the local x axis: hit G  X X

Thanks.  So is axis and origin synonymous?  I see origin quite a bit and it seems they are simply referring to the axis of the object(s).

https://www.blender.org/manual/editors/3dview/transform/origns.html


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So I am having this bug where my model in a game is transparent when you look at it from a certain angle

so my question is how would i go about getting rid of that transparency?

It looks like flipped normals. Try to select faces of that geometry and in the left toolbar select Shading / UV tab -> Normals: Recalculate. Or select only those "transparent" faces and hit Flip Direction.

so i don't think i have any normals... i think haha.


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Blender only showing a small sliver of objects in 3D View
Here is what the issue looks like:

I fixed this by pressing View>Toggle Quad View, and then Toggling off quad view with the same menu

I have no idea whether this is a bug or some weird sliver-view mode, but toggling Quad view on and off fixed it for me too.
Update: It's a feature called "clipping region." I must have hit 'ctrl+b' by mistake when I meant to just hit 'b' for a border selection.


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Splitting Blender animation into separate clips
I am new to Blender and working on a uni project with a very close deadline and really really in need to help. I've created an animated character in blender that I am importing into Unity.
The character has a rigged hair mesh and a rigged dress mesh parented to the rigged body.   (See screenshot)
I was unaware of the action editor when i started so, I used the dopesheet to create a run cycle and a jump animation all in one animation clip. I then animated the hair and dress to they move with the running body. I need to import this into unity but am having huge issues and was wondering if someone could help:

Is there anyway I can merge all the animation for the hair, dress an body together into one animation clip. That way I would have, One animation clip for the run and one animation clip for the jump.

If not how do I split the animations that I have all in one animation clip, into separate animation clips. So that I can have - character_runcycle, character_jump, hair_runcycle, hair_run, hair_jump. But then I have no idea how I would set this up in Unity.

Can someone please please help?
I tried using the F button to create new animation clips but I couldn't separate out the hair from the dress animations even though in the animation timeline the keyframes were only for the hair. I'm so completely confused, this is all very new to me and i am working to a VERY tight deadline for my uni project deadline so any advice is needed and much appreciated.
Thank you so much in advance! xxx

How to create a new action

Press the F-Button so it is darkened to keep your existing action in the blend file even when you save and reload it. Otherwise you might loose your animation. So in case you're uncertain make a backup copy.
Press the  button to unlink the action.
Press the New button to create a new action.

Copy frames from one action to another

Switch between your actions by pressing the  button and choose your desired action from the dropdown menu
Select a frame range by pressing the B key to activate the border select and select a range of frames in the dopesheet editor.
Press Ctrl + C or press the  button in the header menu to copy frames to a clipboard
Press Ctrl + D or press the  button in the header menu to paste the frames at the current cursor location (green line)


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How do you slice a joined model into equal slices?
I would like to take a complex model with many joined object and slice the whole thing in into regular slices. I have tried Bisect and Ctrl R but that doesn't work on a joined object. Any help?

Related : How can I slice an object horizontally into equal pieces?

You can use the Boolean modifier in intersection mode for this.

Add a box (cube) the size of the desired slice
Add a Boolean modifier to the object you want to cut into slices
Position the box precisely on the slicing axis (Z in the example above).
Duplicate the original object and apply the modifier to add a slice.

You probably could benefit from useing knife project from different views (eg. Right / Top / Left / Bottom).
Please see this solution: Knife Project.
In your case you would have to just walk through these steps multiple times, until you have the sections that you need.
The movie ['The Cell' - released year 2000] used this effect to show the internal anatomy of a horse.


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Convert *.FBX to Solid for Physics Sim
I have downloaded a .fbx model from mixamo and import into Blender 2.80 beta without issues.
However, I want to perform a physics sim with that model by draping a cloth over the model and unvealing it. However, there is no option for me to set the .fbx model as a rigid body or collision target.
Do I need to convert the .fbx model into a mesh or solid? If so, how can I do it?
Thanks.

The FBX should presumably include a mesh when it is imported. Most likely if it came from Mixamo it also includes an armature, and the mesh will be parented to that armature.
Make sure you select the mesh, not the armature, and then you should be able to add physics properties to the mesh.
In this case you want to go to the Physics tab of the properties editor and add collision to the object. This will tell any cloth objects that this object should be treated as an obstacle.


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Blender is saving as a blend1 file, not blend
I teach Blender to classes of game design students in the University of California and a student came to me yesterday with a problem I haven't seen before. She's created a very simple file, but when it's saved Blender puts a .blend1 extension on it every time, not the normal .blend. This means that after it's saved twice there are two .blend1 files in the directory, and no .blend file. I have no idea why this is happening. What has she done? Anyone seen this before?
thanks - Chris

They're identical. No, I have no idea how that's possible either. I thought I posted a screenshot, but for some reason it's not appearing. Anyway, the names are identical.

It would be interesting to take a look at User Prefs File tab regarding that feature setup, see http://blender.stackexchange.com/questions/1212/blender-saves-a-new-file-every-time. As it stands, it makes .blend1 to be .blend2, .blend to be .blend1, and then saves a blend. It could be a bug if it works partially..

That's Blender's file versioning system. A very subtle but quite helpful feature. When you open the settings panel, under File, you can specify how many previous versions of a file you want to keep around on your computer.
So everytime you hit save, Blender maintains a stack of previous versions of the same file so you have some backup of your work and don't overwrite your progress when saving.

In the above screenshot, the last 5 versions of one .blend file are saved. All suffixed individually (.blend1, .blend2 and so on).
You can enable showing file versions in the open file dialog if you want to pick a specific version from your save history (red arrow). And also you can toggle showing normal .blend files in that dialog (green arrow) which is what your student probably did.

Hope this helps!

@DuaneDibbley yes that was an accident, I fixed it!

Thanks - and I wasn't aware of the filter, useful - but her file consistently saves as a blend1 file. There are two blend1 files in the directory, which is crazy, but that's how it is.


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Dividing square columns into triangular prisms
How do I bisect square-faced columns along their diagonals, so that each square column becomes 4 triangular columns (prisms), thus making each square face into 4 right triangles?

Easiest way is to go back a little and erase part of what you have done f you really want them as separate prisms.
Erase all but the bottom faces, search for the operator Poke Faces Alt+P and it will automatically break them into triangles.

If you need each triangle extruded as a separate prism you need an additional step before extrusion.
Select all diagonals, using the Select Similar Shift+G operator > Direction option and then rip the edges with the Rip operator V. Do the same for the opposite direction and the square subdivisions if you had not done so before yet.

Then just extrude them back up to create the prisms

Thanks! However, the 25 columns in the screenshot were each separate objects. I have successfully performed all of your steps on one of the columns, and all of the prism vertices are now present, but it still remains one object. How do I now separate the mesh into 4 new independent objects, each being one of the prisms?

Enter edit mode i one of the meshes, select all and press P > Separate > Loose Parts, that should create a bunch of different objects. Have in mind however that unless you specifically need so, that high number of similar objects should probably be turned into clone instances, instead of having a scene full of similar independent objects with duplicate mesh data.


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Bone sizing won't work
When I try to change the thickness of the bones by pressing crtl alt S, nothing happens.  Any ideas or suggestions?

are you in Edit Mode? And have you switched the Armature Display to BBones?

could you please accept the answer if it helped you?

Not every kind of bones have tickness, only "B-Bones" and "Envelope".

To adjust the size of the bones you need to be in the edit mode.  You can enter edit mode by selecting the object and hitting Tab.


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Macbook OS v10.11.6 Can't Open Blender
I am getting the following error message...
"The application “Blender” can’t be opened."
No follow up information, no "...because we can't identify the developer, etc.," just that.
Please help!

A user that had the same "Blender can't be opened" error posted here The answer for them was this response by RyanMDev "Try re-downloading the app, "... "and make sure you use "Archive Utility" to decompress the zip file, sometimes other zip tools can corrupt the file."

go to security and privacy and click on general then click on open anyway

Go to System Preferences.

Then go to Security & Privacy

Click on "Open Anyway"


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Artifacts after render

I have taken over this project. I need to render this with a new UVMap/Shape however Im getting these lines appear.
Here is a partial of the UVMap/Shape. I believe the error is coming from location the bunched up faces on the UVMap/Shape.

Any ideas?

Fixed it by dissolving some of the edges.


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How to get the distance from one vertex to other vertex along the normal polygon?
I need to get a distance from the vertex to the vertex along the normal of the polygon.
Look, I've got a polygon that I want to move to its normal to any too.
In this case, I move the polygon with index 36 to the vertex with index 31 to the normals.
I just include snapping to the vertex with the closest parameter. I get the distance of 0.3568.
How can I reach the distance of 0.3568 between the 30 and 31 vertex using Python?

Use a dot product between the normal and the distance vector for the distance along normal.
import bpy
import numpy as np
from mathutils import Vector

# Use active object and active face in its mesh
ob = bpy.context.object
mesh = ob.data
normal = mesh.polygons[mesh.polygons.active].normal

# v1 is the origin point and v2 is moved to v1 along the active face normal
v1 = mesh.vertices[30]
v2 = mesh.vertices[31]

dvec = v1.co-v2.co
dnormal = np.dot(dvec, normal)

v2.co += Vector(dnormal*normal)

Thenk very much!

authors: Влад Киндюшов


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Is this Smart UV Unwrap good topology?
I am trying to unwrap a roller model.
However, I don't know what a good topology would look like.
I think that good UVs should always be rectangular and not curved, is that correct? That would mean hours of moving vertices on my UV map around, wouldn't it?
I am especially unsure about the UV that I have painted a red arrow besides.
I have uploaded the model here: http://www.pasteall.org/blend/38562
Sorry for the broad range of sub-questions, I am not sure where exactely my problem starts. :-)
Any thoughts on this are very welcome!
Thank you.

You could unwrap by hand, marking as seams middle loop and part of loop around wheel. This should give you very basic version of unwrap. You may want to place some small seams across the model to minimize the stretch. Note that if using texture painting, the seams' location won't be so important.

@MrZak Should I unwrap the hi poly model or can I also unwrap a lo poly model and project it back onto the hi poly model?

If I understand right, you'd like to render lowpoly mesh, baking the normal map from highpoly. So you should not project lowpoly onto the highpoly, rather than use details from highpoly to lowpoly so to reduce polycount of the mesh you're going to render at the same time increasing its details level. In order to bake the normal map, you'll need to unwrap the highpoly. But to assign a texture and render, you'll need to unwrap lowpoly mesh.

@MrZak Yes, I want to make a lo-poly game model. So you are saying that I need to unwrap both the hi and lo poly model? Sorry, I have not understood it yet.

Just to rectify - the lowpoly mesh has to be unwrapped, while it's not so important to unwrap a highpoly and you may do that for the sake of completeness.


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Should "Intruding" be used here?
I would like to create a sunken area.

I wonder what would be the best way to achieve this.
Should "intruding" (the opposite of extruding, I guess) be used here?
Scaling would not easily work because the neighbouring vertices would also be moved. I would have to introduce 2 extra ringcuts to avoid moving the neighbouring vertices.
Could anybody tell me the best way to achieve what I want?
Thank you.

It's kind of hard to tell what you are after from that picture, do you have a better reference image?

Unfortunately this is the best that I have. Should I extrude and then scale? Seems like the best option for me right now.

Try [Alt]+[E] > vertex normals or [E] > [S] > [Shift]+[Z].

I don't quite know how to interpret the image, but here is a possibility:
Switch into edge or vertex selection mode. Press ⎈ CtrlR to add a loop cut through the face ring in question, making sure to slide the new loop all the way down to the loop below it.

Press S and then ⇧ ShiftZ to scale the new edge loop while locking the Z axis to get something like this:


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UV line-up problem
I am trying to model a salt shaker can (not sure what the exact term in English is).
It looks like this:

I have created this:

The unwrapping of the "body" is straight forward, but the top causes me some troubles.
I tried to model everything from a single cube, so I did not make the "lid" a separate object.
The top looks like this:

But somehow the unwrap of the top is really difficult.
Here are my results:

What confuses me is that I have created 2 seams for the top, but I only have 1 UV "area".
If I do not add the second top seam, everything goes berzerk.
I have uploaded the model here:
http://www.pasteall.org/blend/38767
If anybody sees any raw mistakes on my side, I would be happy to hear about them. Thank you.

You did get two islands, they are simple on top of each other

Can you tell me how to separate them?

You select the faces that correspond to the island. Then go into the UV editor and moves those faces over to where you want them. If you wan't 'em to stay separate next time you unwrap, pin them with P

Okay, I think this needs an answer
So what is happening is that your UV islands are stacked. To fix this you will need to grab one of islands. To do this, hover over an offending face and hit L. You will want to have "Keep UV and edit mode selection in sync" selected:

Finally, just use G to move the island into the correct place. You can keep it stuck there by pinning it with P so it won't move back if you unwrap again.


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Merging UVs and textures
I have a model that consists of several separate meshes.
Each mesh has its own UV and texture map.
I would like to merge them and have only 1 UV map and 1 texture map.
Is there a way or a script that would do that painlessly for me?
I have watched videos where this is done with a lot of manual work. I would like to ask if there is an alternative solution, even if it does not use the available space absolutely perfectly.
Thank you!

I think what you are looking for is Texture Atlas
It says it can

Create one UV Map for all objects (non destructive making)

Which sounds like what you need to do.
As far as combining textures, I think you may have to do that manually. In the future I'd advise you to join your UV's first.

What do you mean by "join your UV's first"?

@tmighty Before you paint your texture, to avoid having the merge them afterwards.

It's really simple in Cycles - just assign different materials to different portions of your mesh and use a different UV Map for each. You can have up to 8 UV Maps per mesh object.
I see from the screen shots that you are using Blender Internal though, and I'm not sure if BI supports this.
One thing you can do though, if Texture Atlas doesn't work for you, is lay your images side-by-side in an image editor - not changing the resolution, just ending up with a larger image. So 1024x1024 would become 2048x2048 and you would have 4 textures as one image. Then in the UV/Image Editor scale your UV Map into each of the 4 corners using the 2D Cursor as the scaling Pivot Point. Finally, Join the objects. This should work.


text:
How to get the mouse coordinates in 3space relative to the local coordinates of the active object?
How to get the mouse coordinates in 3space relative to the local coordinates of the active object?
This code gives the position of the mouse relative to the world coordinates, and I need to get exactly local
view_vector = view3d_utils.region_2d_to_vector_3d(region, rv3d, coord)
loc = view3d_utils.region_2d_to_location_3d(region, rv3d, coord, view_vector)

You can obtain the mouse coordinates from a modal operator and use the current event information.

Here I used one of the script templates 'operator modal draw' with little modification in order to use and translate the mouse position.
Your question's relative parts of the code are commented below (please comment if you need more information):
import bpy
import bgl
import blf

from bpy_extras import view3d_utils

def draw_callback_px(self, context):
    font_id = 0
    blf.position(font_id, 15, 100, 0)
    blf.size(font_id, 12, 72)
    blf.draw(font_id, "Mouse position: " + str(self.mouse_pos[0]) + "/" + str(self.mouse_pos[1]) )
    blf.position(font_id, 15, 115, 0)
    blf.draw(font_id, "3D position from " + self.object.name + ": " + str(self.loc[0]) + "/" + str(self.loc[1]) + "/" + str(self.loc[2])  )

class ModalDrawOperator(bpy.types.Operator):
    """Draw a line with the mouse"""
    bl_idname = "view3d.modal_operator"
    bl_label = "Simple Modal View3D Operator"

    def modal(self, context, event):
        context.area.tag_redraw()

        if event.type == 'MOUSEMOVE':

            #Get the mouse position thanks to the event
            self.mouse_pos = [event.mouse_region_x, event.mouse_region_y]

            #Contextual active object, 2D and 3D regions
            self.object = bpy.context.object
            region = bpy.context.region
            region3D = bpy.context.space_data.region_3d

            #The direction indicated by the mouse position from the current view
            view_vector = view3d_utils.region_2d_to_vector_3d(region, region3D, self.mouse_pos)
            #The 3D location in this direction
            self.loc = view3d_utils.region_2d_to_location_3d(region, region3D, self.mouse_pos, view_vector)
            #The 3D location converted in object local coordinates
            self.loc = self.object.matrix_world.inverted() * self.loc

        elif event.type in {'ESC'}:
            bpy.types.SpaceView3D.draw_handler_remove(self._handle, 'WINDOW')
            return {'CANCELLED'}

        return {'PASS_THROUGH'}

    def invoke(self, context, event):
        if context.area.type == 'VIEW_3D':
            args = (self, context)
            self._handle = bpy.types.SpaceView3D.draw_handler_add(draw_callback_px, args, 'WINDOW', 'POST_PIXEL')

            #Keeps mouse position current 3D location and current object for the draw callback
            #(not needed to make it self attribute if you don't want to use the callback)
            self.mouse_pos = [0,0]
            self.loc = [0,0,0]
            self.object = None

            context.window_manager.modal_handler_add(self)
            return {'RUNNING_MODAL'}
        else:
            self.report({'WARNING'}, "View3D not found, cannot run operator")
            return {'CANCELLED'}

def register():
    bpy.utils.register_class(ModalDrawOperator)

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

if __name__ == "__main__":
    register()

I tried to do it for 2 days! Thank you so much!

authors: Влад Киндюшов


text:
How get position and derection the manipulator?
I need to get the position and directions of the manipulator for drawing a square in the 3d window.

it seems you mean the orthogonal direction from the selected face? that's called the face "normal" (face local z axis) but if you wish just to draw something like a rectangular "hole" in that face, you don't need to know its direction vector, though (and there would be no easy method to use it anyway to draw something along that direction): you can extrude the face edges scaling them toward inside.

I want to draw a square at the intersection of the axes http://take.ms/66Wve

see if this other questions (and answers) can help you http://blender.stackexchange.com/questions/7150/python-orient-light-to-polygon-face-normal-as-direction or http://blender.stackexchange.com/questions/26116/script-access-to-tangent-and-bitangent-per-face-how

This is not exactly what I was looking for, I have enough knowledge to find the position of the Median and orentation, but this is not what I'm looking for. I thought maybe in Blender api there is a function that will allow 2 - 3 lines of code to get the position and derection

maybe this one? http://blender.stackexchange.com/questions/26053/get-the-selected-median-point-in-python

Oh, well, I'm glad you made some progress... I'm deleting my answer, since I completely misunderstood what you were asking. If you have now an answer, even partial, to you own question, you could consider adding an answer yourself, below: it will help everyone else. I can help with english, if needed :)

A little later I will answer with a code. Thanks for the extraneous activities you paid

authors: Влад Киндюшов


text:
As in addon preferences add a button to install hotkeys?
As in addon preferences add a button to install hotkeys?
http://take.ms/15Voa

This shows how to setup a keymap.

https://blenderartists.org/forum/showthread.php?417586-Keymap-for-addons


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Trigonometry in blender
Please help me find the length between two dots with Blender api. That value will be the sine.  After that I need to find cassettes of the triangle I'll get.

Thank.

The Pythagorean theorem works in three dimensions.

I need to find the cassettes and not the hypotenuse

Are the red lines always in the direction of the global axes? Are the blue points always in the yz plane? I assume you have the coordinates of the two blue points stored as Vectors, is this correct? Is there something about the grid mesh interesting for the problem?

The points are the vectors, the coordinates of the vertices. Vertices can be in any planes. Red lines can be in any field, the only constant is their angle of 90 degrees

Your problem is still not accurately described. If the points (p1 and p2) are not in a certain plane then no unique right triangle exists. But in the case they are: the cathetus is just the difference of the z coordiantes or the difference of the y coordinates, e.g. Vector([0,p1.y-p2.y,0].

Can you elaborate on what you mean by cassette me thinks  @Dimali on track with cathetus 2 points only define a line.  Need 3 points to define a plane. Will need another point, or another direction vector like say the z axis Vector((0, 0, 1))  in which case your vector v = p2 - p1 and the z axis cross with angle v.angle(z_axis) and the cathetus will be sin and cos of this angle times v.length.

authors: Влад Киндюшов


text:
Get data modifier "Subsurf" after rayСast
I use rayCast to get index of a polygon under the cursor. After that i check the object for modifiers, if there are modifiers I use this:
obj.to_mesh(context.scene, apply_modifiers=True, settings='PREVIEW')
So I can get edges and vertices of that polygon. But this code doesn't work with Subsurf modifier.
.to_mesh()
Indexes mess. How can I solve this problem? I don't want to use Bmesh, because it takes a lot of time to create bm on heavy meshes.

mesh = obj.to_mesh(...) makes a new mesh from the  object with the modifiers applied.  Kinda like applying all modifiers, but not on obj.data on a copy.   Are you linking it to object obj.data = mesh before running  your raycast.... but the subsurf modified mesh copy will have a lot more faces than the original ...   Without code it's a bit difficult to decipher what is going on in your gif.

Code this https://github.com/Darcvizer/q_p/blob/master/utilities.py

I'm need get polygons after rayCast even if it is created by a modifier

authors: Влад Киндюшов


text:
adding effects like smoke
Hi I'm looking for a way to add a poof of smoke to my video. I'm still new so I'm not sure how to do it on blender. I guess I would need to know how to overlay a video onto another to add the effect. If I had the video could I do that?

You should be able to do what you want relatively easily with Blender, but this is not the place to ask for full blown tutorials. What have you tried so far, what have you got already? This question is to broad, please post instead specific parts of the workflow you have difficulties in.

Not to take anything from @Kristof Meirlaen's answer, I take a more simplistic approach -
An easy way overall is to texture a 2D plane in the 3D window with the video of the pot, or preferably, make it the background image/video.  If it is made the background don't forget to increase it's opacity to 100% in that background image panel.
Back in the 3D window, texture another 2D plane with an "Alpha Layered" (See below) video for the poof-of-smoke.  You have to set the smoke plane to start at the desired Blender frame number so it doesn't start up until required.  This is done in the texture properties under the "Image tab" -->"Start".(bottom left of the tab)  Enter the required "BLENDER TIMELINE" frame number where the smoke video is to start.
You'll also need to tick the "Auto Refresh" box to make it play the video.
On the premise that you are using the background image option, view it from the camera so you'll see the pot.  Align the camera so the smoke is positioned exactly as desired.
Render it all with the Open GL renderer for speed, or Blender's internal renderer if you like watching the grass grow!  (Top left of 3D window under the "Render" drop down menu.
The anim here took me 45 mins, and admittedly a quick and dirty example.  It was started from scratch, pot, particles, smoke and bubbling liquid all created in Blender.  The smoke puff was as described above however, a "Cumulous cloud" made with Blender's cloud generator and saved as an alpha layered pic to be textured onto a 2D plane.  The plane was animated. (scaling, rotated etc)
Hope this gives you something to start from...

PS:  You mention that you're new so some info -
To align the camera whilst viewing through it, select the camera (right click on it), press N, ---> open the "View" tab and tick "Lock to camera view".
You can then use the mouse and buttons to move/rotate/zoom the camera to wherever you like as you would a first person view in a game.
Don't forget to untick that box again, or you could lose the smoke's alignment with the background image.
Further hint - if your machine does as mine does occasionally, starts rendering in solid mode, hit escape, and start the render again.  The 2nd attempt usually works properly.
If you don't have a "Smoke-poof" video, an "Alpha Layered" image might do.  Just animate the 2D plane that it's texturing, by increasing it's size (scaling) from nothing to maximum over a few frames and move the entire plane upwards. Once it's at a decent size,  make it rotate a little, or even shrink back to nothing if that suits. The smoke's shape can also be distorted and bent in various stages by doing that to the 2D plane.
Making a puff of smoke is a simple matter in Blender.  Start with the cube, scale it up a little and press T to bring up the Tools panel at left.  Open the "Create" tab and at the bottom, press "Cloud Generator".   This will open up a small menu.  Tick 'Particles', then select Cumulous from the list, press "Generate cloud" button.
A cube inside your original cube will appear with what looks like a clog of black cotton inside that.  Press F12 to render it as a good looking cloud!
The pic is taken from the 3D window's camera so it should be lined up fairly well.  If not adjust the view as mentioned above.
To give the cloud's outer edges "fluffiness" and make it's surrounding background invisible, we have to add transparency. We do this by rendering it with an alpha layer.
Goto the right hand properties panel (SH-SPACE), select the camera icon near the top. (2nd from left) and after setting it's output dimensions and folder etc,  goto the "Shading" tab and change the Alpha setting to "Transparent".
In the "Output" tab, select the format at left to PNG, compression to about 15$ and at the right, click on it's RGBA box. (The A is for alpha)
In the timeline set the frames to start at 1 and end at 1 also.  This will produce a .png alpha layered pic file in your nominated output folder.
From the 3D window press "N" to bring up the viewport's parameters.
Open the "Display" tab, tick "Only Render" and "World Background".
Press N again to close the panel
Go back up to the top left of the 3D window's Render Drop-down and click on "Render animation".  We have to use Blender's internal render in order to get a proper cloud pic.
At this point you can make a cup of tea/coffee while it renders the cloud.  It does a good job though.
This can be your smoke "poof" image which can be coloured, shaded, distorted, shaped and animated any way you like.
The pic shows how Cu clouds can look in their original form.  This pair was made to sail lazily across an alien sky.

This video describes what you are looking for: https://www.youtube.com/watch?v=Hro1BIWFEDQ
The video uses images, but you can apply the same process for videos.

Link only answers are discourage here at BSE, if the link goes dead your answer becomes void and useless for future visitors. Please add this as a comment instead, or ideally you are welcome to edit your answer and improve it with some actual information on how to achieve the desired effect.


text:
Blender cant handle 20k objects?
I'm trying to build something big like palace or Egypt pyramid. Always blender gets freezing because the high numbers of clubs and planes. So, can't finish my work !!.
My PC [16 ram - 64bits - processor 3930k - GTX 680 4GB]
How to speed up blender performance ? How to reach 50K cubes without freezing ?

You need to figure out what the bottle neck is. Monitor your CPU core usage, ram usage, GPU ram usage, etc. If it's true that it is a hardware bottleneck then upgrade your HW or get a program that uses your hardware better.

Blender as reported by some users is a lot better in large volume objects as compared to other (commercial) 3d tools. have you checked latest version of blender 2.78 i've heard it had memory optimizations for GPU, though you got more CPU mem so perhaps you better disable GPU rendering and make sure all goes CPU using your 16GB ram.

Thank you guys for you reply. but no one give me a solution !. I'm not talking about 5K. 20K make blender freezing. and way to solve this ?

It when it reach 20K. it fully stop working. So, I understand from you that my issue is 16ram is not enough.

Not sure if this could helps, but I made a test with a 32Gb machine. Duplicate 4096 cubes (to 8192)  took 2 seconds, duplicate again to 16384 took 9 seconds, dup again to 32768 tooks about 2 minutes, but the last "dup" to 65536 cubes takes 16 minutes! The memory allocation does not change so much (about 5Gb), but the time changes exponentially  and the UI looks totally unresponsive during the dup. After create 65k cubes, the 3d view works normally (rotation, translation, etc.) if I select all objects, but it "freezes" if I try to select only one or two cubes of the set.


text:
Texture looks very bad?

The texture appears not good on the object. I need it to fit the size.

Did you set up the uvs and have the texture match the uv size?

unwrap and smart uV? is this correct??

From what I see in your screenshot, your UV islands don't fit the scale of your model. This is almost always the case if you didn't apply the scale of your object.
Move the mouse to your 3D viewport, be sure to be in Object Mode, then hit Ctrl+A, which should open the "Apply" menu. Select "Scale".

After that you need to unwrap your object again to get the exact UV representation of your model.

No big change. Still the same. Maybe the texture is small ?

Try rescaling some of the UV faces so they have the same proportions as the model. I find it helps a lot when doing a good texture, it takes a little bit of time but the results are good.
Hope this helps.

Manually...not good at all. It will take long time from me.


text:
Creating shapes without deleting mesh?

Use wireframe on sphere can give me a good shape of holes without delete the mesh. I want to replace these holes with other shape like Heart or thunder. A shape of empty heart instead of a hole. How to do it ?

That would mean another approach to creating that sphere. It can be hand modeling one part and arraying all across the sphere or using dupliframes to spread objects along another (parent) object. Another way may be Tissue addon. See http://blender.stackexchange.com/questions/58605/tissue-addon-how-to-create-pattern-on-sphere

So, nothing easy will be done like wireframe. OK. the three methods you mentioned are good and i will try them. but what i was thinking on is can texture help me with this ? If i have black&white picture of a heart. can blender identify these heats and delete them from the sphere ? something easy.

Yes that's possible, use method described here http://blender.stackexchange.com/questions/46424/add-a-transparent-image-on-top-of-a-material. Basically it's just to create image of heart, setup 2 materials (or mix 2 shaders), make UV map so image of heart is placed on every face you choose and that should work. The basic setup may be like here


text:
Use Vertex Painter for texturing?
I'm trying to use Vertex paint to texturing my cube. But colors never show-up in the UVmap window or when export it !?

I don't know where is my fault.

Don't you want Texture Paint instead Vertex Paint?

With Vertex Paint you are directly coloring model's mesh - so this technique doesn't use UV mapping to apply any kind of texture.
If you want to paint a texture (image), you need to switch to Texture Paint mode insted of Vertex Paint.


text:
Curve with a hook?

I linked the curve point with a empty object. curve moves with this object"hook" but when I rotate or change size the curve not changing. How to fix this?

It does work for me... could you add some details about what is hooked inside the curve?

This what I do. Add curve -> path, click on edit mode and choose any point from the curve. Ctrl+H choose first option.

You should upload your file using this link: http://blend-exchange.giantcowfilms.com/

I solved. I choose "Path" not "Bezire". Thank you Lemon.


text:
Select all bones on one click?

How to select all bones by one click for recored. can blender do that ?

why don't you just use the A key?

OK. yes, A key will select all bones but not add it in drop sheet box (look at red box on image). I have to click on every bone to add it in drop sheet box. all bones should be in the drop sheet box without click on every one.

The dope sheet, like any other animation editors, will display only objects that have keyframes. If you select an object that doesn't have any keyframe, it won't show up there. You need to add a keyframe first.
Press A, then all you have to do is press I on frame one. That would set all the starting positions for the skeletons.


text:
Edges connected in strange way?
I'm trying to edit my model but I found that when rotate any edge or move vertex from left/right side, the other side is moving too ? Like there is a mirror but there is not !! I think something is connected between those vertexs but I don't know what is that thing !!

You must disable X Mirror and Topology mirror in the
Mesh Options panel.
See the image below.


text:
Wheel speed get slow?
I made a wheel rolling. The animation show a bet slow speed when start and end it. How to fix this. here is my file [http://www.filedropper.com/wheel]

I believe your referring to the curve on the animation of an object. When you set keyframes or keys in Blender, it makes a graph of how the property you keyed changes over time. By default, the curve has bezier easing, so it tries to animate more smoothly. This results in your wheel slowly starting to spin and slowing down before it stops.
You can change how the animation behaves by editing your keyframes as curves in the graph editor window. You probably want to make your curve linear.
SteveW gives a good explanation of linear interpolation for Blender animations in this question:
How do I make animations a steady speed?


text:
shrink sticks section
I have an object made from several sticks (boxes) I want to shrink the section of the sticks without changing the size of the whole thing, just thinner wood pieces. Is there a clever way to resize it in the proper way? If possible without redoing it, obviously xD

press alt+s in x axis or y axis (any one axis)

In object mode alt+s reset scale. I don't want to enter edit mode because then I have to enter each stick separately

u can join all stick ctrl+J you can try in object model alt+s

ctrl+J was a great idea, now they are all together. alt +s seams to be doing something good but it keeps the x axis while modifying the other two. Is there a way to select the z axis ?

select z axis means i did not get


text:
render scene TO a skydome
Is it possible to render my scene into a skydome?
I created a lowpoly game I want the sky with clouds and mountains in the back of the scene to be in a skydome (in Unity) and just the ground with the trees and that stuff to be actual mesh.
I'm developing VR for cardboard so trying to minimize the polys in scene but .. I need control over the background, cannot just go and download a texture.
PS: I've been told that for VR skybox is not adviced and skydome is the way to go. Correct me if I'm wrong.

Related http://blender.stackexchange.com/questions/13431/how-do-i-bake-an-animated-sky-box-using-cycles/13435#13435

Does Unity take equirectangular environment maps? How about cube maps? If it can use either of those, see this.

@Mentalist I've been dealing with it and I would really say it does not :(
Any other clue ?

I got curious and decided to RTFM. Unity takes cube maps, essentially. But instead of one texture, it uses 6 individual ones. This info can be found in the Unity documentation. So you can simply follow these steps up to the part about compositing, and stop there because instead of compositing you will load each of the 6 images into Unity individually.

As for a "skybox" vs a "skydome" where VR is concerned, the most info I was able to find with a quick search was in this thread on the Oculus forums. Read the comment by user Pyry. And as a result of what I read there I then found this other thread discussing a Rift-specific skybox. I don't know much about Unity or Oculus, but I know that Unity supports cube maps, so why don't you try that and let me know how it goes? I'm curious too.

as far as I read (did not check your link yet) skybox performs per-pixel operations that are not welcome in VR environment. What I tried so far (and seems to be working) I created a mirror sfere in the center of the blender scene and I bake its surface. At the end I get one UV sphere with a texture that shows all the image around... not bad so far .. .


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Deselect objects that do not have UVMap?
I am in need of a way to remove a UV Map datablock of the same name from all selected objects in my scene. I have accomplished this...
import bpy

for obj in bpy.context.selected_objects:
    uvt = obj.data.uv_textures
    uvt.remove(uvt['UVMap'])

BUT I am looking to improve the functionality of my code to filter through all the selected objects, check to see which objects have the unwanted UV Map datablock, and remove the UVMap from only the matching objects.
For example: Plane.001 has "UVMap" & "Map2", and Plane.002 has only "Map2". Right now, if I have both objects selected, I get an error saying that it couldn't find bpy_prop_collection[key] "UVMap" and fails to execute the script. This must be because Plane.002 doesn't have a "UVMap" datablock...
Here's my current code:
import bpy

for obj in bpy.context.selected_objects:
    uvt = obj.data.uv_textures
    if uvt != "UVMap":
        obj.select = False

    uvt.remove(uvt['UVMap'])

How can I have blender deselect Plane.002 and then run the script only on objects that actually have "UVMap" datablock?

obj.data.uv_textures is a list of uvmaps. Each item in the list has a name property that you can test -
import bpy

for obj in bpy.context.selected_objects:
    uvt = obj.data.uv_textures
    for m in uvt:
        if m.name == "UVMap":
            obj.data.uv_textures.remove(m)


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while rendering animation the mirrored part by mirror modifier is not showing in the output(to MPEG)...help?
title says it all.i made a simple mesh using mirror and animated it but while animating using defaults only the original half is showing up not the one which is mirrored by blender.help will be appreciated,thanks!

Could it be you accidentally turned the modifier off for rendering?


text:
Video doesn't show up in render
I have never tried to do this so I am sure I am doing something wrong, but I have no idea what. It shows in the preview window but not in the final animation.

It could be many things... If you don't tell us how you are composing the image in the background. It's that a plane? Or you use the compositor? Or... Please provide a blend file as an example http://blend-exchange.giantcowfilms.com/ and be sure you have checked basic things like the render visibility button in the outline or the ray visibility in the object panel

It is not a plane, and I am not using the compositor.... Maybe that is my problem?
 (http://blend-exchange.giantcowfilms.com/b/1108/)

The blend file that you uploaded has no background.

Yes it does... I don't get it.

Images used as background in the 3D viewport are used for reference only and will not render unless you choose to combine them with the scene using the compositor.
Open a Node Editor window. Add a movie clip node and select your video clip. Set the movie clip to be used as the background input on an Alpha Over node and plug the render layers as foreground.
For Blender Render the setup is like this:

(click on the image to enlarge)
To Render using cycles this is the node setup:

Make sure that the compostitng box is checked:


text:
Physics driven character movement
I've got an armature with a collision-mesh hooked up to it. The idea is now that by only using animations the character would move around in the world. For example pushing off a wall in Zero-G would propel the character in the opposite direction.

I haven't figured it out yet so I'm hoping that I've explained it good enough.


text:
Just select one group
I have made a chair that contains several objects that I have made into one group. Then later I have copied that group because I want more chairs in my scene.
But when I want to move or remove one of the chairs, I click on one object in the that group and press SHIFT + G and then select Group. But then all groups (Chairs) are selected! Is there a way to just select the group I clicked on?

When you duplicated the chairs, you might have just duplicated the objects into the same group. Try removing the second group of chairs from the group then adding them to their own group.

Is there any reason in using groups then? Their usage is mostly for convenience which means you add objects to a group and then avoid adding objects themselves, rather than group instance instead (Shift+A > Group).

So, the solution is to duplicate the first group and then remove from all groups and then create a new group for that chair? And then do the same thing for each chair?

That depends on what you'd like ot do. If you want to make parts of a chair to be present in only one group, then you select original chair parts (without their duplicates), add them to a group, delete all their duplicates and add a group instance from Shift+A menu. I'm not sure what is your desired result. See https://docs.blender.org/manual/ja/dev/editors/3dview/object/properties/relations/groups.html

The group that an object belongs to is a property, and that property is copied into any copied objects. You don't need to update the group of each object individually, you can change one, then select all the rest (with the active object being the one in the new group) then press Ctrl+shift+G


text:
Move vertex away from edge in current direction
The Slide tool GG is perfect to move vertices along an edge when modeling organic shapes. But what if I want to move a vertex (make the edge longer) in the end of an edge away, but still in the current direction as the edge? Is there a way to do that?

Like this? https://blender.stackexchange.com/questions/14892/how-to-slide-geometry-past-an-edge/14894#14894 Or this? https://blender.stackexchange.com/questions/2981/vertex-slide-past-edge-limit/2982#2982


text:
Change opacity transparent image texture?
I'm using a transparent image texture of humans on a plane for architectural scenes. Before I load the image to the Image Texture Node, I change the opacity in Gimp, like 50%, so that you can see through just a little bit. But I wonder if there is a simple way to do this in the node setup instead of Gimp?
I have search but I just find tutorials about how to use transparent images, but that I already know about.
This is the node setup I'm using:

To do what you're currently doing in Gimp, you would simply need to disconnect the Alpha link from the Factor and manually set the Factor to 0.5.  That should give you 50% Transparent and 50% Diffuse.  Make sure the Transparent node is pure white.

@bertmoog Thanks for the reply. When I disconnect the alpha from the Factor, the transparent areas around the human in the image, become black!

@MrZak Thanks for the reply. The area around the human is already transparent and not visible. I want to change the opacity of the human, the part in the image that isn't transparent.

I think it was meant that you need to add one more Tranpsarent shader to the tree before one with Alpha factor and set mixing of it and Diffuse to 0.5.

@MrZak I'm trying all kinds of combinations, but nothing works! Should I add a new Diffuse node and a new Transparent node and then a new Mix node? Then...where do I connect them?

You can insert "math" node between Texture alpha output and Mix shader Fac input.
Alpha 0 = full transparency. Use math node to add 0,5 and results is 50% transparency.
EDIT: optionally you can use ColorRamp, Bright Contrast, Gamma, RGB Curves to tweak values. Or you can use MixRGB and mix alpha channel with other grayscale color using different blending modes.

Thanks for the answer! But it's not the transparency value I want to change. If I use and Math node, the not visible areas of the image goes from fully transparent to darker and darker and finally total black. I just wnat to change the visible part of the transparent .png image and change the opacity of that part. Perhaps not possible!?

@cegaton Yes, you are right. Thanks for addition, I add it to my answer :-)

@3D-kreativ - depend on the case. Also there is option paint alpha mask manually, and combine them if need. You can do it directly in Blender. Alpha is nothing else than values from 0 to 1. Grayscale image is the same. So you can tweak it like image and you can tweak it a lot. But of course, you can't change initial shape without editing original image/alpha or combine it with other one

@Shubol3D Thanks for the help, but I guess it's easier to do this with Gimp as I have done before. In gimp I cut out a human from an image and create a new image with a transparent background and then I paste the human into the new image. Then I can change the opacity of the human layer to total visible or lower the opacity down to invisible. If I set the opacity to 50% I can see through the human, because I don't want it to be a obstacle and prevent me from see other details in the scene. I just thought this was possible to do with the nodes.


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Rigging a hose to follow a robot arm
I'm doing an industrial robot and I want a hose from the base up to the robot arm and I want the hose to follow the robot arm movement in a natural way. Is this possible and what approach is the best? Do I need to rigg the hose with several bones
 and then animate the hoses bones for every key frame or is there a way that the hose just follow the robot arm in an automatic way?

This question shares the same general principle: https://blender.stackexchange.com/questions/41235/rig-that-reacts-to-gravity

Google is your friend http://www.rab3d.com/tut_blen_2-63_hooks.php

The only thing unsatisfactory about the Rab3D method is that the hose is allowed to stretch, and it's not using physics, so you would need to keyframe it manually. In some cases this will be fine. But I personally prefer a rig that uses physics and responds to the motion of the mechanical arm.

I'd opt for a softbody simulation on a string of edges, hooked at each end. You can then add a Skin modifier with Subsurface modifier to fill it out to a hose.

@DuarteFarrajotaRamos This tutorial and it's approach worked fine for my project. My question is solved! Thanks!


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Only reflection from one side of glass material
I'm doing an architectural visualization and I'm using a glass material for the balconies and a fence, but I get strange effects that doesn't look good. It seems that the glass from the windows on the facade that are behind the balconies and the glass fence get some strange distortion!? Is this really correct behavior? Compare the two images.
Anyway it doesn't look nice and I wonder if it possible to prevent this? I only want reflection from the front of the balconies and the glass fence like the sky.

It looks to me as if your balcony glass has no thickness or the normals are bad. Try either adding thickness (eg, Solidify modifier) or recalculate normals. For a physical glass pane the glass would pass through two surfaces - the front face and the.back face - and would refract opposite ways. With only one surface or with bad normals the refraction is being applied one way only - it's as if everything viewed through the balcony glass is within a solid volume of glass. I don't think that's a reflection your seeing but a refraction of the building through the glass.
Here's an image to demonstrate :

The right-most example is for 'correct' refraction - where the light is bent towards the 'normal' on entry to the glass and away from the 'normal' on leaving the other side. If the Normal of the back surface is pointing the wrong way (the middle example) then the 'exiting' ray is again bent towards the normal (directing the rays towards your building in your case). A similar situation occurs on the left-most example - where there isn't a back face since the "glass" is only a plane. In that case the light is bent towards the normal but is never bent back - as if the ray remains within the glass.


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Move and snap a group of objects
When I have selected the group and click on the part that I want to move and snap with another stand alone object in object mode, I just get one of the objects in the group, the rest is left behind. Is there another way to move and snap a group?
The snap setting is vertex and closet, despite that, it will not snap completely, it's a distance that looks like 1 cm. Any idea what could cause this?

Related http://blender.stackexchange.com/questions/58022/snap-during-transform-can-not-snap-to-what-i-want/58097#58097

See lemon's great answer bout snapping, you may also be misusing groups or maybe misunderstand how they work. See http://blender.stackexchange.com/questions/47295/sketchup-like-components-case-study-is-it-in-or-even-feasible/47311#47311 for more details about how to use groups


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Bright light from window?
I'm doing an interior scene with Blender and Cycles. Scene has set following setup: Three tall windows. Each window has a portal and the light in the scene comes from a HDRI environment texture. The camera is places far in the room and pointing towards the windows.
My question is a little bit complicated, because I'm looking for an effect, that I don't know the english word for. When I look at other renderings and real photos i catalogues the sun is so bright and so much light flows through the windows, so the things in the background outside of the windows is almost unvisible.
How can I achieve that in my scene?

You are probably looking for an over-exposed or burnt exterior, this might be easier to achieve in post production by rendering indoors and outdoors as separate layers.

@DuarteFarrajotaRamos OK, thanks for your comment!


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How to import 2D/3D CAD drawing into Blender and how to convert wireframes to faces?
I'm trying to import CAD drawings into Blender. I have read and looked at some tutorials about this, but it's not working! I can use DraftSight to transform a .dwg file to .svg, but to transform a .dwg to .dxf does not work, despite that I try all kinds .dxf versions!
I have also tested some other software like IrfanView, but to be able to handle .dwg files you have to buy an extra plugin and I have also looked at Teigha which is now called ODA File Converter and it's not free anymore.
What other options are there to handle cad drawings in Blender? Are there any other better file formats? I really need to solve this because I have a client that expect me to be able to handle CAD drawings in Blender.
Is it only possible to import 2D CAD files or is it also possible to import 3D CAD files and perhaps also view them as solid object and not just view them as wireframes?
When a CAD drawing is imported into Blender, what is the best working method to transform the wireframes into faces? Should I just a use the wireframes in the background and draw new faces with the snap tool or can I convert the wireframes to faces in some other way?
Preciate some tips and guidance about this subject. Thanks!

I regularly use DrafSight to convert DWGs into DXF and import them in Blender without issues. Why is that not an option for you?

Did you ever get this answered? By chance did you develop a working protocol for this? If you did would you please share it? I need to work with CAD files and although I have had some limited success with .STL my geometry is triangular etc. messy to work. and comes with internal geometry I don't need. I need to ask machinery manufacturers to provide me their machines in a 3d format I can use in Blender and I have no clear understanding what I should be asking them for. Help greatly appreciated.


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Background image reduces light from HDRI
I'm building an interior scen consisting of a room with four windows, see image below. Behind the four windows, on the outside I have a plane with a background image to get a nice view from the camera. The light in the scene comes from a Hdri image.
But I guess the plane prevent a lot of light to enter into the room because of the plane? Is there a way hide the plane for the Hdri light, but still be visible for the camera?

There is "Cycles settings" at the bottom of "Object tab". Uncheck everything except "Camera". Thus it will become visible only for camera

@SergeL Thanks for the answer! I have tried that and I didn't saw any difference, but I should check it again.

Not a direct answer, but try increasing the emission of your background plane.


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Possible bug when when using empty as image?
I'm using empty as image for set up of blueprints for car modeling. When I toggle between solid and wireframe in the viewport the images strange things happens with the images! Please look at the second image below. Is this a bug or could it be avoided? I'm not using the x-ray option.
In solid mode:

In wireframe mode:

I think it is better using the backgound panel.

@LeoNas But then I can't see the blueprints in a perspective view!

Try using Images As Planes addon instead, empty images indeed have this limitation


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Possible to control or limit distance of gloss and shadow how it affects other objects?
I'm creating a scene with a room and I wonder if it possible, with the help of nodes, limit the distance of an objects shadow and glossy to nearby objects or as an alternative tell object A not to affect object B but affect the rest of the scene?
I have turned of glossy and shadow in the Cycles setting for an object because I didn't want it to affect another object and it looked nice, but then it affected the rest of the scene in a negative way.
Curious if this is possible?

Sounds like you shouldn't be using a physically based path tracer. Most of those kinds of interactions are generally not physically real and hence not easy to achieve in Cycles. Have a look at the Light Path Node though it may be a waste of resources to be rendering these things in a complex rayracer

Related https://blender.stackexchange.com/questions/96615/fade-out-reflection-in-mirror-with-cycles


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Strange light from glass
I'm doing a scene with a room with a table. On the table I have some wine glasses, but I get this strange light from some of them. The glass to the left looks OK, but the other are not OK. It seems like they are affected by the floor texture!? Or what could be wrong?
I'm almost certain I didn't have this problem when I made the first test render. Then I just tested to see how the wine glasses was effected when I activated the Reflective Caustics and Refractive Caustics, then they got this strange light, but despite that I have unchecked the both Caustics options in the render tab, I still have this light and I don't know how to get rid of it? Any ideas someone?
The wine glasses har not solid. I have used a solidify modifier for the upper part of the glass, while the lower part is more solid. I'm only using the Glass BSDF node.

We are going to need a lot of information about your model for any serious answer, like topology, modifiers, material setup, render settings etc. Please edit your question and provide some screenshots

It looks to me that it could be a problem with the floor material rather than the glass - as if it’s visible to the camera but not when viewed indirectly (through the glass). Try changing the IOR of the glass to 1.0 to make it act as plain transparent - this will eliminate the refractive distortion so you can see what’s happening. Check the floor material for Light Path conditions - eg, is it only visible to camera rays so allowing the environment to shine through when viewed indirectly?

@RichSedman Thanks for your suggestions, but nothing helped. I changed the IOR to 1.0, but still the same white light and the settings for the floor below the Light Path are the usual. If I remove the texture and just use a diffuse color, still the same problem. Any other ideas that could solve this?

I solved it with a temporary solution by a small plane object that I placed  behind the chairs that is invisible for the camera and that seems to work. I have just rendered a small part of the scene, but it looks fine. The white light is gone. It would be interesting to know what causing this problem and why this simple plane between the glass and the floor solves the problem?

Glad you’ve solved it - that seems very strange. You should post your solution as an answer to this question and it would also be good to ask a new question about the odd behaviour - ideally providing your blend file (uploaded to blend-exchange as mentioned above).

@RichSedman Now it's definitely solved. The scene has two rooms and each room has it own floor object. When I was looking for the settings for the floor, I clicked on the floor near the camera, but that was not the floor in the background behind the wine glasses, it vad the other floor object and now when I clicked on that floor, I discovered that the Transmission option below the objects Cycles Settings was deactivated. Now when this is selected again it works fine without the solution I wrote about before. :)


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Copy and paste X, Y and Z values
In Blender 2.79 there is a new option that allow you to copy all the transform values (x, y, z) at once in the N-menu with CTRL + ALT + C for copy and CTRL + ALT + V for paste. But this seems only to work with objects in object mode, not if I want change the position of a vertex in edit mode. What could be the reason for that?!

One object has one location. How would you expect it to work in edit mode if more than one vertex is selected?

@batFINGER In my question I wrote "a vertex", how could that be "if more than one vertex is selected" ? A vertex is one vertex.

It's looks like an very new feature, maybe this functional isn't implemented yet?


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How to make sharp and rounded corners
I'm trying all kinds of options to make sharp edges and rounded corners for an excavator arm. Apart from just using bevel, I also have tried to use "make sharp" and "edge crease", but it doesn't look nice. Any suggestion have I can improve my model with more edges and where to put them or any other approach to make rounded corners with sharp edges?

If you're modeling using subdivision, at its simplest, this sort of topology will give you a rounded corner: supporting loops close to the sharp edges, and looser on the round corner. You have a degree of control over the tightness of the corner by sliding the edges on either side of it.
[

However, if, for example, you you wanted a perfect circular arc in the corner, breaking instantly to perfectly orthogonal edges, you might choose a bevel, as suggested by atek.

With the knife tool cut this way

To make an edge. With the edge selected Press Ctrl+B to bevel and with the mouse wheel make the segments and how much round shape you need


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Smoothing across multiple objects
I am trying to manually create a fragmented spherical object in Blender for use in a Unity game. When i create a separate object from the mesh the smoothing is no longer contiguous so it becomes obvious that the object is already fragmented.
Is there a way for the fragments to appear like the original whole and contiguous unbroken sphere with no gaps and consistent shading? Can I instruct Blender to smooth across all objects instead of smoothing individual fragments?
I am quite new to modeling and would appreciate any pointers.
Thanks!

Yes, this can be done.

keep a single whole object(this is the reference for correct normals).
enable auto-smooth on all broken parts(needed for custom normals to show).
using the Normal Edit modifier on the broken parts to copy the normals from the whole object to the broken parts.

If you want to avoid some slow-downs from continued updates, you can apply the modifiers to store the custom normals.


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Cycles color diffuse baking results in black image

As you can see on the image above the baked image appears black with exeption to the handle part. I use the free PBR node from Blender Brit for the metal material. The normals are facing the right way. And enabling ambient occlusion didn't solve the problem neighter.

You cannot bake a glossy material.  I think that is your problem.  By looking at the picture, it appears that the handle is the only thing that does not have a glossy material.  Try removing the gloss material from the blade and changing it to a diffuse material.  You shouldn't have a problem after you change that.

Thanks! But is there another way to bake the glossy material so I can use it in a game engine?

There is no way to bake it, but it is possible to create a metal material for the game engine.  Here is a video I found very helpful: https://www.youtube.com/watch?v=AaFAqBlznmI&t=1s


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How do i show the whole object in the camera view before i render?
I am trying to render an animation, I have set up the camera in the right position but not all of the object is showing in the camera view, like its in shadow. how can i fix this?
Thanks

This is due to the clipping being set too small. Note that there are separate clipping settings for the camera and the viewport, see http://blender.stackexchange.com/q/7185/599

Increase the clipping end of the camera from camera setting.

authors: ΙΣΙΔΩΡΟΣ ΠΑΠΠΑΣ


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Orange edges in object mode
i'm having a problem where some edges are shown orange while in object mode and won't go away.

Check if there isn't another object in the same place which was selected in Object mode.

Checked, i'm only working with one object.

it like if those edges were not counted as edges when exported, because sketchfab reinterpretates them.

I bet you accidentally duplicated those edges (Shift D) while you were working with the mesh in Edit Mode. Check your geometry.

I think i found the error, those were floating edges, not attached to any face, just a string in the air between two vertex, i'm just deleting them and replacing them using the knife tool (k). i think it will work now :D

In Blender the selected/active object are outlined in edit mode by varous  coloured lines which by default are highlite only on the meshes's boundaries, aka the edges who are shared by less than two faces

Notice that this behaviour make clearly visible those objects who behave like paths or profiles, who have edges not connecting any faces and fall in the category explained above.

In your case you probably have both cases in the same mesh, overlayed.

If you want to get rid of the edges not connecting any faces, you can take advantage of the Delete Loose tool:


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Show the Image of the selected Image Texture Node in Image Editor
I dug up this old post about a CMYK-ish shader:
Blender halftone pattern filter
In the blend file you can load from there, you find that whenever you select an Image Texture Node the image will show up in the Image Editor view. I really like that behavior and want to use it in my own files but can't find the settings for that. The blend file does not contain any scrips as well.
I found a feature request on Right-Click-Select, which confused me a lot because - is that not a feature? and if it's not, why is it in this stackexchange project?
Can anybody help? (or suggest an Addon? :D)
obligatory apology in advance if I missed something obvious.

Hi :). It works just like you described in Blender 3.1. Are you sure you don't have an image pinned?

That seems to be an option in the built-in Amaranth toolset addon although I've never tried it. The docs at https://pablovazquez.art/amaranth/ are pretty old, but it's mentioned under the Nodes Editor heading.

Ok, so as mentioned, this seems to be a default behavior in Blender..
In my case it started to work after i added a new empty image texture node in the Shader Editor. When I selected my original Image Node the corresponding image showed up in the Editor.
When I select another image in the Editor and then select the Node, the image does not change to the one of the node tho. Is that the usual behavior? I am not sure if i think it makes sense to keep the manually selected image or if it feels like a bug :D

Hi :). Yes that's expected behavior. You can open multiple image editors side by side :)


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Blender to Puredata via OSC
I'm trying to hook blender up to Puredata via OSC. I want to send the location of objects within Blender to Pure data, so when objects get closer to other objects sounds are triggered within Pure data.
I'm still a novice within Blender.


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how to create snow in cycles?
It seems that snow is generally created using procedurals. In cycles, a completely node base system is much too complex for a beginner like me. My basic node setup looks like this:

and my scene is lighted with 3 lamps like this:

(a plane is used just behing suzanne to light the translucency), but my render looks as dull as this:

How can I make more of snow and less ice looking texture for suzanne?

Perhaps Andrew Price could help you out here. He did a snow scene tutorial, available on his site. It's long, but it's a step-by-step look at how to get soft, slushy and glittery snow using both procedural techniques and texture-based techniques.
He starts talking about shading around 58:00, but the whole video is worth listening to because he talks about textures, displacements and lighting that can add some much-needed chaos into the scene.
Suzanne, on the other hand, might need some adjustment from his shader setup. You might need to increase the subsurface scattering (SSS) influence because you're trying to get light through the object, not just glitter on the surface. Just remember that SSS will increase your render times significantly, so use it sparingly.

By the way can image textures be used for snow or are procedurals necessary?

It is possible to use image textures, but I feel it would be more complex than nodes and will bloat your scene size. It would involve nodes anyway, with masks, a spec map, bump, diffuse, etc. Using a node tree offers a very quick and easy way to edit the material and provides consistency across the entire object.

Blender is now much faster rendering subsurface scattering, so I will give it a try. Thanks.


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how does the color ramp interpolation work?
how does the interpolation of the color ramp node in cycle affect the behaviour of the color ramp. During modelling the interpolation meant the shape of the curve, but while using node it must be something different........... How would this affect the values physically and technically(i.e. how would it carry out internally and how would blender interpret the input value of the color ramp)?

It is actually based on a curve, the steepness of the curve showing how quickly the color changes, etc. Each of the points can be seen as control points on a 2D curve, with the value showing height, and position showing side-to-side positioning.

Is there any way to visualize this in the real time viewport?

I have an idea of how to visualize it

An easy way to visualize this is to add a plane with a displacement modifier with a Blend texture and Colors > Ramp selected. Start by adding and subdividing a plane:

You can add a subdivision-surface modifier as well for added detail. Now add a Displace modifier, and click New to make a new texture. Go to the texture panel and select Blend:

Now you can edit the waypoints and the interpolation types as you wish and view their results in real time. This will really help you see how the colors are mixed using a color-ramp.

Constant:

B-Spline:

Linear:

Cardinal:

Ease:

To visualize Cycles
Add a plane, unwrap it and add a gradient texture to an emission shader:
LINEAR

QUADRATIC

Easing

Diagonal

Spherical

Quadratic Sphere

Radial

There is a slight amount of easing. Do not use cardinal interpolation for height maps or other depth data


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How to create rust procedurally?
I've been trying to come up with an idea of creating rust procedurally and tried searching up for tutorials on various sites which only made use of image textures.
Procedural being a hard practise as it is, I wanted to create a rust texture for various meshes in blender but the one I did come up with, not so very realistic:
does anyone have some ideas on how to create rust using only procedurals inside of blender?

First thing - rust does not fade in and out, a given point is either rusty it's not, not halfway rusty.  To create this effect run the noise texture you are using for a mask through a "Greater Than" node.

How's this?

@PGmath, it looks like scrap paper stuck with glue on top on steeled suzanne but is it possible to create it in blender? It looks kind of intriguing.

@bzal the material PGmath would really work great and look good if it's a piece of worn leather. Hope he shares his node tree with us.

@hawkenfox, I tried it but it looks like a brown cow suzanne. I don't know if I can post a pic in the comment but I don't know how would it be used.  Could you demonstrate this?

@bzal  That's a first test, I meant to add an answer with an updated version yesterday, but I had a busy weekend.  I'll try to get it fixed up and an answer posted ASAP.

In the book "Blender 2.6 Cycles: Materials and texture cookbook" by Enrico Valenza, published by Packt publishing you can find more than 40 recipes, one of them is for procedural rust.

Hope the image is self explanatory enough. Hope it gives you a good starting point.
Some Explaination
Click on the image to view it in full resolution. You can copy the nodes and will get the same results. The Musgrave Texture are used as the mask to create the rust patch. A Second Musgrave Texture is given variation in the values, acts as the mask for the silver non rusty parts of the material. The noise material just provide a little color variation for the silver material, so it is not flat and boring.
The node pretty much tells you how it's constructed. The bottom image shows the closeup of the material, just for a visual reference that in closeup the material is still pretty convincing.

Additional Side Notes

Regarding the UV image, I use it for visual testing uv unwrap to
  prevent tile stretching on none procedure map, for this case I did not
  use it at all as it is indeed a procedural material, so no uv work is
  required on the model at all. It's just the default setup for my
  workflow when I start a new file.

@hawkenfox, what is the UV image for? Is it being used for texture paint?

@hawkenfox, would it be Ok if I made a tutorial based on this?

@ bzal go ahead whatever I share here is free and open. Well you could add a link on your video to this page when you are done.

@hawkenfox This is great... How would you increase the ratio of the rust to bare metal?

@Dontwalk Sorry for the late reply been buzzzing around lately ... so to answer your question I would just play with the values in the Musgrave texture since they were use to generate the rust patches. Play with it and experiment ... have fun most of all :)

What hex colors for the rust?

I was able to follow this in Blender 2.82a, it worked perfectly!


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setting position of each instance with captured attribute node to each vertex
I have a cube and cone , and I want to place each cone in the corner of the cube.
The simple way to do it would be:

But, I'm trying to understand how capture attribute works, so I'm trying to set the position for these instances explicitly by using the positions that I capture from the geometry(cube). I did something like this:

It seems to superimpose all 6 instances into the median of the cube. I suppose it's a bit unreasonable for me to expect it would match the number of instance for each vertex position.
Then does that mean the value of the captured attribute is the median of all the position of vertices? Then again, I also do know that it can be actually use to get face/vertex specific data like this:

So I'm confused, How does the capture attribute actually work? Does it give an average of all set of data in the spreadsheet? And how can I use this to set the position of the given set of instances to the position of each vertex?

In your second image, geometry output of the capture attribute is linked to nothing. In consequence its output is always (0,0,0). This output should be connected among so that there is a defined context to capture into.

@lemon , but where do I actually connect it to?

What Does Capture Attribute Add to Geometry?

The capture attribute node output should be connected to a (chain of) element(s) in order to be used by them.

Think about it like so:
In the cube geometry flow,
We capture (capture is known at cube vertex/point level)
This capture is linked to "instance on points" (capture is known at instance level)
This is linked to "set position" (capture is know of it as we are talking about instance position, which know the capture)
etc.
Read more about capture attribute node

I somehow get an intuition for it, but, using the same method how would you put a cone on each face of the cube? I tried changing the domain to face which didn't quite work ( thought it should have gotten the position of each face which should had been 6 points, but cones don't appear accordingly) https://ctrl.vi/i/BGqTc5iFf

Well, 8 points, 6 faces... so not directly. Use "mesh to point" with "face" option.


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Is there a way to Import a Houdini Generated Volume (VDB) into Blender Cycles?
Is there a way to Import a Houdini Generated Volume  (VDB) into Blender Cycles?
We are working on a Uni project, and we cant seem to get a VDB into blender working at all. Has anyone done this before and is able to help.
Much appreciated Guys!

Blender can use OpenVDB for smoke cache files (there's an option in the Smoke Cache domain settings to switch between Point Cache format and OpenVDB) but I don't know much about Houdini or whether the OpenVDB format it uses is anything like compatible with Blender.
Another option would be to transform your Houdini VDB file into a format that can be used in Blender - such as an image format as used in this answer to question "Voxel Data in Cycles". There the voxel data is converted (using Python - similar to the Smoke2EXR add-on mentioned in the link in that answer (see https://baldingwizard.wixsite.com/blog/tutorial-mesh-to-volume)) into an image containing multiple slices of the volume. Maths nodes can then be used to transform from the 3D coordinates into 2D coordinates within the relevant 'slice' and this can then be rendered as a volume.
Obviously for this to work you will need to develop something to convert from Houdini VDB into multiple image slices.
Note : It would also be useful if you could supply a sample Houdini VDB file to be able to allow others to investigate how this could be achieved.

Until recently there has not been support for OpenVDB in Blender. In Blender 2.83, that is about to be released in a matter of weeks, there will be support for importing OpenVDB files and a more general volume object type will be introduced. The alpha of 2.83 is already available for download to try.


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Strategies for walls
Not sure why I can't find any info on this.
When trying to model the inside of a house, I find it difficult to figure out how to both have a workflow that allows for both having more advanced features like walls with different thickness, slanted walls, varying height and using bevels. In the attached image, I have tried 2 methods.
I find the upper one a lot easier to work with. I basically model some "lego" bricks, and piece them together. The big drawback is I cannot figure out how to do stuff like bevel the edges. On the image I used the bevel modifier to show the "problem". But even bevelling single edges gives me issues, for example around the windows. Because there are multiple island bordering each other.
The method used in the lower example otoh I find very difficult to use when I have irregular walls (varying thickness, slanted). It requires adding a lot of geometry as well, whenever there's a feature (like a window).

Most helpful video I've found so far on this is:
https://www.youtube.com/watch?v=Cunh57XjRv4
But still. All his example are rather simple.
Can someone explain or point me to a tutorial on how to achieve the kind of simpleness the "upper" method has, but still allowing for stuff like bevels?

Have you considered enabling the (built-in) add-on "Archipack".  Once added you will have a new menu item in 3d-view "Add" called Archipack, and will also have Arhipack in the  "Create" sidebar tab.  You can create various Floor, Wall, Window, and misc furniture objects that can save loads of effort and time.

Here is the link for the Arhipack home page:  https://blender-archipack.org/

Thanks, I do use that for windows and doors. But not walls. Maybe it's just me not understanding it, but I'm not sure how the walls make it a lot better than just extruding parts manually. My main issues are with slanted walls (not shown in example, but when the upper half of a wall is slanted like 45 degrees (like on the top floor of a house)), or when a part of the wall is thinner than the rest, like in the image above where the wall section under the window is thinner (recessing?).

Ok, I found this video from the same guy:
https://www.youtube.com/watch?v=kZD8sSX7NtU
It uses booleans to cut out doors and windows. Seems to work for the above. Haven't tried it yet for slanted walls, but here's hoping it will do.
I was reluctant to use booleans first because they seemed so buggy. May not be buggy, just very hard to use whenever something is a little off. In my case, turned out one of my normals was pointing inwards and that was confusing everything.