Why should I never ever use "Convert Premul" on Cycles renders? On this question, When trying to overlay images using Alpha Over for green screen work , I used premultiply Alpha, it was the only option that would give me clean key without the background bleeding over. A comment states Never use that "Convert Premul" option on Cycles renders. Ever.

Why?

You misread the answer, and my suggestion wasn't terribly clear. Any imager should be "pro" associated (aka crap term "premultiplied") alpha.
There is a good reason, and I will expand this answer when I find some time later.
The bottom line is that only associated alpha models a real-world correlation, where unassociated doesn't.
Only associated alpha manages to model both occlusion and emission. Glows, convolutions,  motion blurs, and a plethora of other transparent / translucent effects can only be modeled with associated alpha.
Think of alpha as selecting the over operation. The Alpha over node actually assumes associated alpha and performs the correct over operation, which is FG+(1-FG.a)BG.RGB.
Unassociated alpha can do none of these things. This is at least one of the reasons that PNGs are never used in a post production pipeline as they are incapable of using associated alpha. From the EXR Technical Introduction:

Calling the color channels “premultiplied” does not mean that the
color values in an image have actually been multiplied by alpha at
some  point  during the creation of the image, or that pixels with
zero alpha and non-zero color channels are  illegal. Non-zero color
with zero alpha is legal; such a pixel represents an object that emits
light even though it is completely transparent, for example, a candle
flame or a lens flare.
In  the  visual  effects  industry  premultiplied  color  channels
are  the norm, and  application  software packages typically use
internal image representations that are also premultiplied.

http://www.openexr.com/TechnicalIntroduction.pdf
From the actual TIFF specification, regarding TIFFTAG_EXTRASAMPLES tag that denotes what type of samples are stored:

The difference between associated alpha and unassociated alpha is not just a matter of taste or a matter of maths.

Associated alpha is generally interpreted as true transparency information.

http://www.awaresystems.be/imaging/tiff/tifftags/extrasamples.html
Again, never, ever, use unassociated (crap term "straight" or "key") alpha, and instead associate it. This is what the unfortunately named "Convert Premul" does in the Alpha Over node. However, on direct Cycles renders, it is already associated and is never needed.
There is exactly one edge case that you must unassociate alpha before processing, and that is on colour corrections. To do so, you must be careful and skip on zero alpha. An alpha value of zero with nonzero RGB is entirely valid, and represents an emission without occlusion. Examples include reflections, glows, glares, flares, fires, etc.
The only time "Convert Premul" should ever be used is if the imager knows she is feeding it unassociated alpha, but like a good imager, she would never be using anything except the One True Alpha, associated alpha.
Further reading:
Zap Anderssen of Autodesk now:
http://forums.cgsociety.org/archive/index.php?t-278718.html
Larry Gritz of OpenImageIO and Sony Pictures imaging team:
http://oiio-dev.openimageio.narkive.com/aaTdld9U/handling-unassociated-alpha#post2
Jeremy Selan, two time Academy Award winning imager behind OpenColorIO, now at Valve:
https://groups.google.com/forum/m/#!topic/ocio-dev/ZehKhUFqhjc
The Infamous Adobe Photoshop thread. Pay key attention to the names, as there are many imaging legends in it, including Zap Anderssen dismantling one of the head developers of Photoshop, only to have Florian Kainz of ILM back up Zap's take on it:
http://forums.adobe.com/thread/369637
EXR Technical Introduction:
http://www.openexr.com/TechnicalIntroduction.pdf
I likely misspoke in the original question as, from memory, I can't remember exactly what that goofy keying node delivers in terms of alpha. I suspect it is unassociated, which makes the "Convert Premul" option work. Generally however, to avoid oopsies in the code etc., it is prudent to manually associate your alpha and control the merging to prevent data loss in the RGB channels. I still stand by the advice, however; always try to maintain a consistent state of alpha, and when you deviate, do so under scrutiny.
Additional information for implementation via nodes or software
There are three states for imagery with emission values encoded in the RGB channel, and an additional occlusion channel.

Associated. The RGB emissions are “as is” and represent the final emissions required. This may include zero alpha with nonzero RGB, such as the aforementioned case of reflections, fire, etc. To disassociate the emissions from the degree of occlusion, use a divide skip zero alpha. Leave any RGB emissions in the zero alpha case, as they could be glares, flares, fire, or reflections.
Unassociated. Here the alpha is not encoded. That is, the RGB represents the emissions without occlusion taken into account. To associate in the case of Unassociated alpha, use a simple multiply which will scale the RGB emissions by the linear degree of occlusion.
Disassociated. Here the alpha started life properly encoded as associated alpha, but has been disassociated to conduct colour transforms. To properly reassociate the data, multiply but skip zero alpha. That is, leave any emissions in the RGB channel as is.


Random movement of objects to X,Y axes I wrote the following Python, which is not ideal for me as it seems to be moving on the YZ axis
import bpy
import random

Num_Min = -0.01
Num_Max = 0.01

Target_Objects = bpy.context.selected_objects
for Target_Obj in Target_Objects:
 Target_Obj.location[1] = random.uniform(Num_Min, Num_Max)
 Target_Obj.location[2] = random.uniform(Num_Min, Num_Max)

I want to move to the XY axis.
Also, I want to control the range that can be moved by setting "Min & Max".
Thank you.

Not sure what do you mean XY axis, But you might misunderstand the subscription for array in python. They should start at 0 not 1. eg. x = [3,6,9]; x[0] # is 3. The Object.location (Vector) stand for [X,Y,Z] So you might need to use location[0], location[1] instead.
Instead of using number to retrieve axis, ones should use properties to get the axis for clearance. eg. location.x = 1.0; location.y = 2.0
import bpy
import random

constrain = (-0.01, 0.01) # I prefer to use tuple for min, max value

for target_obj in bpy.context.selected_objects: # PEP8 recommend to use lower snake case
  target_obj.location.x = random.uniform(*constrain) # And unpack them using *
  target_obj.location.y = random.uniform(*constrain)
  continue
  # Another approach
  target_obj.location.xy = (random.uniform(*constrain), random.uniform(*constrain))
  # There can be called and manipulated by combination as well


Hand is not glued to gun as expected I have a character mesh with a 2 handed gun held in his right arm and supported by left arm. IK and constraints are set properly as suggested here: Rigging two handed weapon

Still, it seems like the left hand can't keep up with the gun, making it feel like it is lagging. If I set Time Remapping from 100-100 to 100-900 (making the animation run slower), it is a lot better, but it really isn't the right way to fix it. The general concept of IK is there, the hand follows the gun nicely, but this issue completely ruins it for using it in animated renders.

I am looking for a solution to effectively glue the left hand to the desired place on the gun. Iterations are set to maximum in case of every IK constrain.

If you need any more informations let me know.

Solution: The gun and body armatures were separate, so I deleted the original gun armature and created one inside the body armature. Using IK that targets the last bone of the gun and uses the gun mesh as a pole. I could achieve an almost, if not completely perfect result.
Took me way too long to find it myself, so I'll leave it here for others, who suffer from the same problem.


How can I render objects with very shiny surfaces? I am trying to render a kitchen sink / Faucet

Here is another reference image of what I want

What I have got so far is this

Settings for World:

I have used an environment map HDRI with 0 saturation.

Material settings:

Triad with glossy, glass anisotropic and there mix shader combinations and the new principled bsdf shader too but didn't get the required result.

Studio lights:
Followed multiple youtube tutorials on setting up studio lights in blender but the results were not what I wanted.

LEAVING CYCLES :

Decided to try some other software
So, Downloaded Keyshot 5 but keyshot wasn't able to produce cycles like results LoL.

Not : I have always struggled to get professional quality product rendering in cycles

So now I'm back in cycles looking for help.

What you are missing is proper lighting.

The main idea is that you are not photographing an object, but what is being reflected on it.

Ditch the HDR and start from scratch (Unless you have an HDR that reproduces a photographic studio used to photograph the exact same object from the exact point of view, any other HDR will be largely useless for what you want to do)

You have an object that is reflecting the environment around it.

Start by placing a very large plane with an emitter in the scene and see how is being reflected on the surface. Move it around the scene, and notice how the placement helps you reveal or not the shape and qualities of your object. Add a second emitter or just planes with a white surface. Find the correct placement for them. You need a mostly white environment around your object, but having gaps in between the emitters/reflectors will help you reveal the contours and subtle shapes of the object.

Look for websites on how to photograph shiny objects in the real world, there are a lot of them. The same techniques apply for 3D rendering.

This link might help: http://project52pros.com/2014pros/assignment-thirty-five-photographing-a-very-shiny-object/


Adding objects to an animation/0 sized object is still being rendered I am trying to create an animation in Blender and I need to add objects to a scene during the animation.
I am quite not sure, how to do it. Any suggestions?
I have tried to work around it with setting object size to [ 0, 0, 1 ]. I thought that I can achieve required result with scaling this object and then changing its position. However, the object (zero sized - before scaling) is still being rendered as a black line.
Thank you for the help in advance.

To be clear I have searched for an answer for a while. And I have found out that there are quite a lot of solutions to this. Of these, however, 3 options are used the most. Here they are:
#1 Moving the object out of the camera field view (in a single frame).
This is probably the most easy solution of these 3. All you have to do is insert a keyframe where the desired object is in the camera field. Then just move on to the next frame, change the position of the object, so that it is no longer visible in the view of the camera. And on the end just add another keyframe. Voila! Here is the effect of removing/adding objects to the scene. I chose to go with this solution.

#2 Hiding the object in viewport (in a single frame).
The solution that is being used also really often. This option uses Hide in viewport option, which is available in Scene Collection. Basically add new keyframe, switch to the next frame in your animation timeline. Toggle visibility of the object off and add another keyframe. That's it.

#3 Changing material/texture during animation (in a single frame).
It works pretty much same like all the options listed above. The only difference is that you do not change location or visibility of the object, but you change material/texture of it.


Modify node value in all materials with variable name? I'm trying to automate a process where I have to change a Value node for all materials starting with the prefix mb:. I've been messing with it, but I'm such a novice with Python that I'm stuck.
Looking at the console, I see that the code for changing the value of the node would be this:
bpy.data.materials["mb:o:150:27"].node_tree.nodes["Value"].outputs[0].default_value = 10
But my issue is that I don't know how I would apply the variable of mb: to the to string in the above line.
Is there any way to do this?

You want to iterate over all materials and check each material's name. IF it starts with 'mb:' then modify it.
import bpy
for material in bpy.data.materials:
    if material.name.startswith("mb:"):
        material.node_tree.nodes["Value"].outputs[0].default_value = 10


Move object in inches instead of feet? Whenever I move an object in blender in unit mode(Imperial), it always make it in feet. For example, if I type G Y 12, it will move 12 feet. How can I make it move 12 inches instead?

When performing any action (such grabbing) that has a number input during the modal operator; you must first press = or NumPad * to enable advanced input for the units.
By default the number input for the modal operators is set to simple, that is why typing in any units after the value does not work.

I would highly suggest everybody reads the release notes for the number input feature


Walking Neural Networks In Blender? Is there a way to do this in Blender on Windows?

If this specific one isn't a capability, are there other neural net things that I would be able to experiment with in/with Blender?

With that example, I'd like to be able to model ideas I had for new manual wheelchairs, and if the program can learn to use them, then maybe I can have it built in real life.

You should be able to use neural networks in Blender for instance with Tensorflow and Keras. There are several problems though, while Blender has several ways to simulate physics, it does not have muscle simulation. The interaction between neural network an physics may be very complicated. Adjusting the state based on the output of the neural network will require different adjustments to depending on the physics sim. For some there may not even be a way to adjust parameters mid-way. Interactive display and performance will require that the NN is run in a different process so the UI isn't locked.

It may be technically possible, but as of now this would require extensive work and likely modification of Blender's source.


Different camera sizes in same file I know render dimensions are tied to the render settings, but for my architecture scenes it would be very handy to have the option to assign different aspect ratios to different cameras, all in the same scene. Is there a way to do this? (without having to use the timeline)

I can't rule it out 100% but I would be very surprised if you could do this per camera. You can change the sensor width and height in the camera settings, but that should not change the aspect in the rendering.

The only solution that comes to mind is a script that hardcodes the desired resolution (and with that the aspect ratio) for each camera and set it up as a driver. Meaning when you hit render it will check which camera is active and assign the resolution that you referenced to that camera.
Let me know if that is an option, then I would try to work out that script. Also: untested, there might be one more step to that. Worst comes to worst we create a tiny script that acts as a render button but does the adaption to your scene before render (that one will work for sure).


Looking for code files I'm working on a project that will be evaluated in my university class "image processing and computer vision":
I'm trying to recreate some experiment we studied in class with Cycles and, in order to do so, i need to access the "sample patter" code: the "correlated multi-jitter" should be the most usefull patter to work on but i can't find the code anywhere.
I already checked the documentation and the wiki and asked on a bunch of groups and pages, but nobody seems capable to help.
Thank to all those who'll answer.
Have a nice day

The implementation of the correlated multi-jitter can be found in blender/intern/cycles/kernel/kernel_jitter.h . The functions are called cmj_sample_1D and cmj_sample_2D. The code is based on Andrew Kensler, "Correlated Multi-Jittered Sampling", Pixar Technical Memo 13-01, 2013.
Here is how you can find this yourself:

Enabled Python Tooltips in the preferences (Edit > Preferences > Interface)
Hover over the sampling pattern drop-down in the UI until the tooltip appears. Take note of properties name, it is sampling_pattern.
Search for sampling_pattern in Blender's code. This can either be done in your local copy of the code or online through Blender's website or its GitHub mirror.
Find the code that implements the property first and try to figure out how it is used. You will notice that the property can be found in blender/intern/cycles/blender/addon/properties.py and the values that can be select for it come from enum_sampling_pattern.
The type that defines the enums that could be assigned can be seen in blender/intern/cycles/render/integrator.cpp and here. The name of the enum is SamplingPattern. The entry SAMPLING_PATTERN_CMJ is for the correlated multi-jitter.
Searching for the occurrences of SAMPLING_PATTERN_CMJ shows that it is used in blender/intern/cycles/kernel/kernel_random.h. The functions to compute the correlated multi-jitter are called cmj_sample_1D and cmj_sample_2D. Both are implemented in blender/intern/cycles/kernel/kernel_jitter.h .


thickness dependent transparency I am using a transparent material but it seems that I only have a transparent surface. How can I get the result that a thinner part of my object is more transparent than a thicker part. I now the answer may be simple but I tried a lot of options but there are simly too many for trial and error. Also I don't find anything like that in the questions. I am using eevee.

I tried the solution with the principal volume and I cranked up the volumetrics samples. The effect is weird. See the second picture.

This happens for all the volume shaders. The right object is a cylinder in reality, the left one is a sphere. In a third image I show the shader setting that I have used.

You can use Principled Volume for that.

Use the Density value to adjust the strength
Larger volumes obscure objects more
For Eevee, crank up the samples in  Render Tab > Volumetrics.


How to change background color in Blender Internal? How can I change this render alpha background to a color?

I tried to change the "horizon color," but it didn't work.

Switch the background alpha from transparent to sky:


How do I model this chrysanthemum crest? I'm trying to do a low poly and high poly version to bake down. I attempted modeling it and planning to subsurf the low poly to get the high. Can't seam to get the round surface right and avoiding ngons without adding too much poly. Is there a smarter way to doing what I did?

It looks like while I was composing my answer someone else beat me to the punch. Nonetheless, I will share what I have. I think you get the gist of it already, but there are some slight differences. I hope you'll find it helpful.

Create the edge outline.

Do a spin extrusion.

Make some Loop Cuts.

Scale down with proportional editing enabled. (Sharp falloff)

Simplify the geometry by merging vertices...

...and dissolving edges.

Add a UV Sphere with the appropriate number of divisions.

Delete the bottom verts.

Do Proportional Editing on the UV (hemi)Sphere too. (Spherical falloff)

Delete the lowest edge loop of the hemisphere.

Merge the pedal's vertices to the center hemisphere.

Duplicate and rotate by 22.5° (360° / 16 pedals)

Merge more vertices.

It may be necessary to Remove Doubles from time to time.

Create a tiling section and use the Array Modifier to complete the circle.

An Empty can be used to specify the rotation angle (22.5°).

Enable the modifier settings "Merge" and "First Last" in order to connect the verts of the mesh as one.

Create the geometry for the smaller pedals.

And give them some height.

Here is the final result:


Particle System - Hair: size jittering - messes up scene I have a project where I rendered out one animation.
Now I see that the palms in my animation jitter in size.

Video here:
https://youtu.be/JowtxnaBUZg

When I examine this effect in Blender I see that it actually is happening and not just an artifact.

So somehow the height of my particle system is being "animated" and I would like to shut it off.

What have I tried:

Looking through all particle settings (I might miss something though)
Looked into Dope Sheet but nothing is in there.

I turned out that I had a Force Field and Wind in my Scene that were supposed to only affect the Smoke, somehow that also affected the Palm Particle System.
I deleted the Force Field and Wind and since I had baked the smoke animation it stayed the same and the palms now don't wiggle anymore.


What is the function of the "Shape Object" tool in particle edit mode? There's little video tutorials on particle edit mode. I would like to know what this tool does.

According to the manual it

  trims hairs to a shape defined by the Shape Object

That means it allows you to create a mesh that surrounds all or part of your model and use it to cut hair that goes outside that mesh.

Increasing the path steps under it also helps give better results.


Intersection Boolean Modifier doesn't work I am currently trying to apply Intersection Boolean Modifier on a Superman model with a Plane.

It works fine for most of the plane positions but at that point on the picture, it cuts all parts and doesn't find any intersection.
I also tried to apply triangulate modifier to plane, solidify modifier to model, removed doubles and recalculated normals but the result still was not satisfying. (I can actually can do it with knife tool but since I am trying to do this operation via python script, knife tool cannot help me I think)
Here is the blend file :

The meshes used in the Boolean modifier should both be manifold (fully enclose a volume) for consistent results as the modifier works based on the volume enclosed by the mesh. Adding a Solidify modifier to the plane will give it thickness so that the modifier has some volume to work with.


Hair particles causing cycles render to hang on 2.9 I don't know if anyone else is having this issue but for some reason a hair particle system is causing cycles renderer to hang at the initializing stage and I have to force quit blender.
If I turn off the particle system the scene renders fine.
I've narrowed it down to the children section, I have it set simple which is the best look for the hair I'm rendering however if I set it to interpolated the scene renders fine but the look isn't what I want.
Can anyone help?
I'm using a Macbook pro 2018. OS Catalina 10.15.7
Blender version 2.91

After some experimenting it seems I was wrong about the memory. I've learned that having too many particles definitely affects memory and render times.
To combat this I reduced the number of children by half which made a huge difference but then the hair looked too thin, so to compensate I thickened up the roots.
It seems that my system will alert me if blender is out of memory when using too complex meshes but not with hair particles. Also my render times have decreased significantly.


"Dimensions" not shown under "Transform" panel I'm just trying to edit the dimensions of a cube, and I've hit 'N' to open the properties panel, but there's no "Dimensions" that I can edit under this tab, just "Median", "Vertices Data", and "Edges Data".  Does anyone know how to get blender to show me the dimensions table?

Thanks

Dimensions do not show in "Edit mode" only in "Object mode"


Fire appears in preview, only renders emission Recently while trying to render fire I run into a problem where the fire shows up in preview but it does not render, only the light that comes from it.

All the settings are at default, I can't seem to find what is causing this as I was perfectly able to render fire before.

I recently had a similiar problem. Your render, in fact, is correct, but the result is displayed incorrectly. This is due to the way alpha is represented in the viewer, which uses straight alpha rather than premultiplied, so emissive volumes like fire can't be properly modelled. For a detailed explanation, see this answer.

To see the fire, just try switching to RGB mode instead of RGBA in the image viewer and you'll see the flames:

As suggested in the linked answer, a solution would be to use an EXR image wich has premultiplied alpha. If you can't use an EXR however, you need to convert the premultiplied alpha to straight alpha in the compositor, then save as e.g. PNG:


How Can Data Sets Be Pulled From Database into Text Objects or As Parameters for Other Objects I would like to build animations based on 2 scenarios that pull data into Blender from SQLite, MongoDB or MySQL database.

One scenario where a bit of text data would become a simple text object would be a movie post credit roll animation. In this case, numerical data from an external file would control the size, radius or constraint controls of objects in the animation.

How can I get information from an external file and use that to control properties (sometimes animated) of various objects?

Your question comprises 3 different topics:

How to query for data in a backend (SQLite or whatever)
How to do that with Python (database drivers / libraries)
How to create animations in Blender programmatically

There's a brief introduction for the latter in the API docs - Animation - and plenty of questions and threads here and on blenderartists.org.

For 1., please refer to the database system's documentation and help channels.

For 2., google and also read about using 3rd party Python modules in Blender.


Some objects disappeared in the modeling tab after render After rendering to see how my model looked so far, most of the objects in my scene disappeared from the modeling tab (using 2.8), they aren't hidden, alt H doesn't bring them back and they are set to be visible in the organizer. They are visible in all tabs except for modeling.

You are in an isolated view inside of the Modeling tab.
Go to View > Local View > Toggle Local View or press Num /.
(Blender 2.7: View > View Global/Local)

You know that you're in isolated mode / local view if it says User Perspective (Local) in the top left corner.


Need emission to NOT cast shadows I want light but no shadows using emission lights. Even though I uncheck the Ray Visibility "Shadow" I'm still getting shadows.

First, the answer to the question:
To get rid of shadows in cycles, you can disable Shadow in the Ray Visibility of the object (not the emitter).

BUT
Those are not shadows you are looking at, they are reflections of the object itself.
You've created a very reflective, almost mirror like material.

Without changing the lights, here's a render using a diffuse shader on the object, the alleged shadows are gone....

Here's the same scene with a glossy only material, showing the reflections on the glossy sirfaces...


How to easily organise your Blender scene? When making complex scenes there should be some kind of "folders" (i.e. like in Adobe Photoshop, layer management) in scene outliner, that can group objects together - but this feature seems not present.

Is there some addon or way to manage scene "like a pro"? I find groups very unfriendly and object parenting is somehow useful, but not quite good in my opinion for right scene organisation.

For a better scene organization I'd suggest use the layer management addon, which is shipped with blender by default:

In addition, the Outliner provides some functionality to display the desired data types like Groups, Same Objects, Selected Objects etc.:


Cant paste flipped pose properly I cant properly flip the pose in dope sheet. I created the 1st half of the walking sequence, now im trying to flip it using shift+ctrl+c(in gif). The problem is it doesnt even paste everything. I tried duplicating it then mirroring it(in gif), i tried to flip it on the x axis.
[]

You've called your bones Left_Shoulder and Right_Shoulder (prefixes), and so on for the other bones, instead of Shoulder_L and Shoulder_R (suffixes). Actually I was a bit surprised that you were able to copy flip with this kind of terminology. That said, it looks like in the Dopesheet, with CtrlC and ShiftCtrlV you still need to use suffixes. I guess it's something they have forgotten to fix: Either you can use prefixes everywhere or you can't, or I miss something...


Can't scale two edge loops around the X axis I have these 2 edge loops and I want to scale them to be further apart, but using S + X and dragging the mouse won't move (along the Y and Z axis it works). I can set them apart manually by taking each one and moving it using G but I want them to be equally apart.

Here is a 'perspective' view of the shape, maybe I did something wrong that prevents me from scaling those loops.

You have 'Individual Origins' set as your pivot point for transformations in the 3D view header toolbar. At the minute each loop is scaling towards it's individual origin but because the loops have no thickness themselves nothing appears to be happening.

You need 'Median Point' set:

This will find the point in between the two edgeloops in 3d space and use that as the origin for transformations.


Multiple Linked Objects with unique Materials / Group Materials override I want to have a Cube in scene A, and linked in scene B, but with different material.

The solution for this problem was found on BlenderArtists.

  click the material tab and you will see a little drop down that says "dat" or "Data". Click that and change it to "Object". Now you can assign the material to the object instead of the mesh or "Data Block".

But what if I have 5000 Cubes in scene A, and I want 4999 of them to be in scene B with different material X, and 1, with material Y.

If I try to "link material" in scene B, with new material, it won't copy "Object" selection. I would have to go over 4999 cubes and change them to "object" in material tab.

I can't join them, and then separate - all objects are in a mess after that (and blender crashes anyway).

Material override for whole scene won't work for me.

Is there any option to override materials in groups? That would solve the problem in some way.

(step 1 from gandalf3's answer)

Set the material datablock to Object, then right click on the drop down and select Copy to selected This is important, if you skip this step 2 will not work.

Select all the objects you want to have the same material, with the active object having the material to be copied to all the others selected. Press CtrlL, and select Materials. It will now link the materials to the Object and not the Data.


strange artifact when rendering volume I'm using a volume scatter shader to render an atmosphere for a planet. To save on time I used a spherical gradient and ran it through a color ramp to get white only on the rims of the sphere. This was then fed into the density value of the volume scatter. When rendered it is behaving as if there are more, smaller spheres of volume inside of it. I'll attach images of my nodes and the results.
Note: The atmosphere and planet are on separate render layers so I can apply a blur to the atmosphere without affecting the planet.

here is the artifact across the entire planet

here is the artifact up close

here is the artifact without the planet

here is the node setup for my atmosphere

here is my compositor node setup

Solution found: Including my directional light in my atmosphere render layer fixed the issue, although I still don't know why. Does anyone know why having them separate would result in that artifact?

The artifact is probably due to the Color Ramp transition method Ease and the fact that your ramp control points are really close to each other. Even though this is inside the planet, it impacts your final render because of the 2 step compositing. I suggest trying B-Spline which should produce smoother transition.

An alternative is to use RGB Curve and play with the curve shape which may give you more control than the ramp for this purpose. Note the Vector Handle vs Auto Handle which impact the shape of the control point, respectively sharp and smooth.


stripe shader no uv unwrapping I need a shader that achieves the effect in this image, stripes of different colors. This image was produced by uv unwrapping but that would be difficult to achieve on a very complex object. The idea is that the object is made of a material of colored layers and is then carved to give this effect. The image is in ortographic projection. The orientation of the stripes should be a parameter.

Thanks for your help.

One way to get stripes is to use a 'Checker Texture' and use a 'Mapping' node to stretch the texture in one axis. Of course this would only produce a two-color striped texture and it appears that you want a multi-colored texture. In that case I think you could layer some 'Checker Textures' using Alpha and offsetting their mapping coordinates. I'll give it a try to see if it's a viable solution and let you know how it goes.

This seems to work (if I understand your question correctly). You would have to play with the values to achieve the thin black line.


How change the colors for annotation? I search how to change the colours of annotation en 2.8 Blender's version, because the « pencil » fort them don't appear.

Thanks a lot

You can select the pencil on the tool panel (arrow) and you change the color using over on the object context menu (press N to pull up) under View.  I've circled where you can change the color.


Can I bake normals and diffuse to combine in a single image My target output is low poly md2 and low poly dae files.
I'm using the high-poly normal map to low-poly object trick.
Looking for a way to bake a final texture that combines the look of the normal map and the color texture into a single image.
Been trying many things. Been having many failure.
Any clues on if this is even possible? I know md2 are ancient. But that is my target.

I'm just answering this because the bounty is almost up and so far there are no accepted answers.
As others have mentioned above, it is possible to bake the "simulated height data" in the form of Ambient Occlusion from a Bump Map being multiplied into the BaseColor.
EXAMPLE:
I made an image of a sphere as it will eventually (truly) be - smooth with no real height data.

I then took the same sphere and added "height" information provided by a Noise Texture and a Bump Node.

From here, you can "add" (multiply) that data to the BaseColor by using an Ambient Occlusion Node.

Before baking, make sure your object has unwrapped UV's As per the baking process,  create a new image, un-check "use alpha" but DO check "32 bit float". Make sure the image is at least 2K (2048x2048).Load the image as a new image texture and have it selected (but not attached) in the material graph for the object.

Then, making sure you're in Cycles, under the Render Properties tab, and under "bake" Set bake type to "diffuse" (since you only need one color image), and click to de-select Direct, and Indirect influence, leaving only Color selected. I also recommend lowering the margin size. Hit the bake button when ready.

Once the bake is complete, go to the UV tab and select "Image > save" to save your image.

You can then load and connect it as a basecolor as you would normally.
The final result looks like this - note the only texture attached is the new BaseColor containing the "impression" of the previous height information:


How to keep origin point/cursor on object I have noticed recently when moving new objects around, it doesn't keep the origin point/cursor on the object. See below - when I move the object, they do not move with the object, which affects the way it rotates, scales etc

Is there any way to set it so that it all moves in one?

Many thanks

this one for blender 2.8 and above
Apart from the answer I found on this forum, this one worked for me.
I was facing this problem where pivot was offset to object

In this you press F3 and type set origin
this will appear

Then I just selected geometry to origin
and the problem was solved,
pivot moved to the center of object.


Create bones on vertices in Python I want to generate several bones on vertices with python. I have figured out how to make an Armature Object, and how to make edit bones within it. Now I need to get these bones onto their appropriate vertices. Can I create them on certain points in the first place? Or can I somehow move them there?

Do I use head, head_local, translate, matrices, or something else?

Using Bmesh to get the required coordinates.

import bpy, bmesh #first import bpy and bmesh
obj = bpy.context.active_object

if obj.mode == 'EDIT':
    bm = bmesh.from_edit_mesh(obj.data)
    vertices = bm.verts

else:
    vertices = obj.data.vertices

verts = [obj.matrix_world * vert.co for vert in vertices] #this should get your coordinates as tuples.

plain_verts = [vert.to_tuple() for vert in verts]
for I in range(0,482):#where you'd like to set your bones i chose from 0 - 482 because i wanted to fill a sphere.
    print(plain_verts[I])#so you can see your data
    bpy.context.scene.cursor_location = (plain_verts[I])#move the cursor to the vertices position.
    bpy.ops.object.armature_add()#this uses blenders menu method to add the bone, at the cursor.

After like 3 minutes of searching online I was able to find this, and by reading the commands in Blender easily figured out how to create a bone.

Is this not what you're looking for?

Or did you want to know how to join and rotate bones?

because that would be

bpy.data.objects['selectedbonesbones'].select = True
bpy.context.scene.objects.active = bpy.data.objects["selectedbonesbones"]

and look here to rotate the bones in pose mode.

If you want to rotate in object mode it should be something like

bpy.data.objects['armature'].rotation_euler[0] = 1
bpy.data.objects['armature'].rotation_euler[1] = 2
bpy.data.objects['armature'].rotation_euler[2] = 3

If you want to rotate in edit mode, well I haven't found anything very useful but you can try this, line 335 to 364. Tell me if it works!


divide vertex into two Is there some quick way to "divide" (bevel) one vertex inside a geometry into two making a edge between them like on the picture?

In this case beveling vertex won't really help as it will create Ngon with too many sides:

While it's possible to fix that Ngon to desired face later it can be cumbersome as original vertices position won't be the case any more.
Instead you can try Rip tool to detach some faces, fill new one and split it. Then dissolve unnecessary geometry. Note though that both procedures - beveling and merging vs ripping and dissolving - take nearly the same amount of effort.

Select vertex where edges are connecting (by the way too many edges are joining at one point there). Then press V to execute Rip tool. Your mouse cursor will affect which part is being ripped, in the case below mouse cursor was to the left top so to rip left faces.

Fill a new face there and split it at the vertices in the middle with Connect Vertex Path tool (J); select vertices first and then execute the tool. It will split the face into 2 triangles.

Then merge unncessary vertex and dissolve edges which are no longer needed.

The result isn't clean, it's more of a middle position between further retopology.


How to find collections where an selected object is linked to? I have an chair model and it is linked to multiple Collections. How to find what collections that the object is linked to ?

There are at least 3 solutions:

If you select the object, go in the Properties panel > Object Data > Collections, you'll see the collections the object is part of:

In the 3D view if you select the object and press ShiftG > Collection, it will display the collections the object is part of:

If you select the object, in the Outliner you'll see an object icon enlighted next to the collections that contain it:


Nicely merging different extrusions I made this teapot:

 HDR "03-19_Night_B" CC BY-ND 4.0 | Scratch Texture CC BY-NC 2.0

Offending geometry here:

How can I make where the spout touches the teapot body bevel nicely so that the teapot body smoothly merges into the spout, rather than the spout simply popping out of it.  Any suggestions?

Blend file

In this case the solidify and the subsurf modifier don't really contribute to the problem, and the texture on the surface is also incidental (ie, not relevant).

The main issue is really the abrupt 'non-transition' between the spout and the body. In your case because the object is Lathe-able geometry (you either used a screw modifier or the Spin tool) you could redo the body with more steps to have finer grained geometry for matching up.

You had a considerable difference in the size of polygons between the body and the spout and that makes it difficult to match up nicely, this image shows a better match between polygon sizes.

Getting the two patches of mesh to match up in a way that would make the merge smooth is not a trivial thing in a polygon modelling tool like Blender. Getting them to approach the same subdivision level is a firs step, but is no guarantee that the end result will be acceptable for close up renders. Regardless it is worth trying.

Blender has all kinds of tools to help you model intricate details

'Vertex Slide'. Shift+V, allows you to move a vertex along any connected edge.
'Knife Project' tool to cut shapes into meshes. Here i've cut the profile of the spout into the Body of the pot to prepare the attempt to merge. (the blue outline of the cutter-mesh is just a Draw Over to help distinguish the meshes involved, it's not part of the tool..)

if you look carefully, this shows the first sign of something we don't want to see. Ngons.

Now you have two problems, how do you match them up?

As soon as you see hideous geometry like this, you know you are going to have a bad time.

Even a bevel here will still give unfavourable results, but it may be one realistic way to get an acceptable transition. Adding an EdgeSplit modifier or Subsurf modifier on-top can smooth it out enough to be acceptable for everything except close-ups.

There are entire tools/software dedicated to dealing with mesh intersections like this. (Groboto, MeshMixer..to name just a few)
(sorry more to come, hence i'm adding this as community wiki I encourage additional editing)


How to make a heat distortion effect? How can I make a heat distortion effect, like you might see around the exhaust of a jet engine?

Simulation

Unfortunately since it's not yet possible to vary the IOR inside an object, it can't be simulated completely.

However, you can at least use a smoke simulation to distort things based on simulated airflow.

Create a fire simulation where the hot air should be. It doesn't have to be very high resolution:

Move the domain to an empty layer (e.g. layer 2), then setup a material for it with some random noise:

This will result in something like this, which we can use to distort the rest of the scene:

Create a new renderlayer and set it to mask the layer the main scene. Also set the main scene renderlayer to exclude the smoke:

Note that I set the number of samples taken for the smoke render layer to 1, and disabled the main passes (using only the emission pass).
Then setup the composite nodes:

Result:


Is there a faster process for converting splines into rigged meshes? I wanted to have my character's arms be more akin to that of a cartoonish noodle, so I decided that the best way to accomplish this would be to create a Bezier curve, create a mesh out of that curve by duplicating and converting it, create an armature from the curve's various points, rig the mesh to that armature, and apply a Spline IK constraint. However, I think that there might be an easier way to do it than how I'm currently accomplishing it. Here's my process.

Here is a simple Bezier curve. I would then proceed to duplicate the curve three times so that I can use each one for a different purpose.

I'd then expand the depth of one of the curves to a suitable value ('0.07 m' in this case) and convert it into a mesh.

Hiding the mesh, I'd move onto another curve, converting it into a mesh while making sure that the depth stayed at a volume of '0 m'. With the mesh being nothing more than a curved line of vertices, I'd then add a Skin modifier. After selecting the modifier's "Create Armature" button and deleting the mesh, I'd have an armature ready for me to utilize.

Before rigging the mesh to the armature, I'd extrude another bone out of the end bone for the sake of accurate deformation.

Allowing the mesh to become visible again, I'd select the mesh and then the armature. I'd then parent the mesh to the armature with empty groups (automatic weights give messy results).

Now here comes the part where I want to rip my hair out.
Since automatic weights don't give me the results I want, I'd select the armature, go to the Object Data properties, go to the "Viewport Display" tab, and check "Names". With that out of the way, I'd select the mesh and go into edit mode. I'd then select a ring of vertices and assign it to the vertex group that properly corresponds with the appropriate bone.

And then I'd do it again.

And again, and again, and again, until I eventually run out of vertex groups to assign the model to.

Now, it's not too big of a deal when I only have 13 bones within this example armature, but if I were to deal with 30 or 50 bones here so that the mesh can look extra smooth while the arm is being deformed by the spline, things suddenly get significantly more tedious to set up than before, especially so if I'm dealing with multiple limbs. After this I'd just add a Spline IK modifier to Bone.11 and add a few fancy hooks to the Bezier curve, but I think you get my problem here.
I don't want to go and apply weights to the various vertex groups in my model so that it responds to every single bone in my armature here. Is there a script/add-on that can do this automatically, or is there a better workflow that would make this sort of thing easier to accomplish?

Skin Modifier
Using the Skin Modifier along with a Subdivision Surface Modifier you can do this rather quickly.
The skin modifier has the option to create an armature for you, so convert your curve to mesh first, and use the modifier.

The spiral in the image below is a very basic example, but you can get the point from it.


How to model an accurate parabolic mirror with a known focal point? I am new to Blender and really enjoying it now, but... I want to make an accurate parabolic mirror with a known focal point. For example, I would want to have it focussed so that a parallel beam could be reflected from the focal point outwards.

This will be 3d printed and then used with a tiny sonic transmitter/receiver set up to map surroundings, for a small rover bot. I think this could be done with a Bezier Curve, at least the general shape could be emulated. But how to make the parabular accurate for the focal point? I am guessing that once the general shape was made, it could be extruded away from the front to make it more solid.

The focal point needs to known so I can add struts to mount the sonic electronics. I'm not worried about scale or size at this point, just the method that I can repeat. Ive looked for some scripts that might help, but not found anything yet.

Thanks for your help.

Add mesh z surface

Enable the add mesh extra objects addon, then from add menu choose add > mesh > math function > math z surface

The equation of a paraboloid with focus f is

(x ** 2 + y ** 2) / (4 * f)

paraboloid with focus at (0, 0, 1)

Thickness can be added with the solidify modifier.


Model disappears above and below origin of armature when I run gltf made in blender on three.js I am currently experiencing an issue of having my blender model disappear in three.js. What happens is that the model will load and it will be visible until I go above or below the origin I had set for the armature inside Blender. I have tried recreating the model and what I have found is that bones that were disconnected but maintained the same parent as connected bones were the ones that would disappear in three.js if the parent bone was not in the same camera view. This is what it looks like in three.js.

The model is probably being culled incorrectly, when the renderer believes it may be offscreen. You can disable that entirely...

model.traverse((object) => {
  if (object.isMesh) object.frustumCulled = false;
});

... although you'll lose the performance benefit of not rendering the object when it's offscreen. An alternative is to manually increase the size of the bounding box:

model.traverse((object) => {
  if (object.isMesh) {
    object.geometry.computeBoundingBox();
    object.geometry.boundingBox.expandByScalar(2);
  }
});

The root of the issue is that the skinning animation happens on the GPU, and the renderer needs to cull objects that aren't visible before drawing them on the GPU. So the animation isn't taken into account in that process currently. Sometimes the skinning data changes the scale of the object, not just its pose, which would exacerbate the problem. More details in https://discourse.threejs.org/t/object-bounds-not-updated-with-animation/3749.

threejs r116


Arrange selected vertices in a curved shape I have a cube and by subdividing faces, now I have a bunch of vertices in each face.

How can I arrange some selected vertices in a curved shape (they are now in a straight line shape)?

Then I want to extrude those curved shape vertices.

Another option is:

removing the row of vertices you want to make curved
adding a Bezier curve in its place.

"Resolution Preview U" should be set to exactly $N-1$ where $N$ is the number of vertices making a side of your cube.

Also, you might want to make sure that the Bezier curve lays completely on the XY plane
converting the curve to mesh
joining the curve and the cube
reconstructing the faces by selecting the two adjacent rows and doing "Bridge Edge Loops" (must be done once per side)


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.

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.


Is there a way to get the edges to be a similar distance appart? I wanted to make the center of this circle be in the center of all the edges of this sphere. I don't want to use ctrl g because that may lead to human error.

You can use vertex snapping for perfect precision.

Enable Vertex Snapping > Center
Select your center vertex and align it (using snapping) if it's not already
Select your ring and snap it to the aligned center vertex.


Array not following curve I'am trying to model a tank wheelchair, I have made a curve for tank treads but when I make array of cubes it is not following the curve. What should I do so that my cubes not only follow the curve but also I could be able to move the cubes along curve to simulate tank tracks?

Your cube must have the same position as the curve (select the curve, hit Shift+S and Place 3D cursor to curve's origin, then select the cube and again Shift+S to move Selection to 3D cursor).
Also, you must apply transformations on the cube so it can properly fit the curve (Ctrl+A).
I have updated and attached your file so you can look at it.


Spin around an object How can I model an object that spins around another object like in this picture (ramp around cylinder).

If you want to create an object that is like in the picture spun around a cylinder, i would suggest to use the screw modifier to get the base shape of the object and later fine tune the result.

Create a curve starting at the outside of the cylinder, making sure the origin is at the center of the cylinder.
Shape the curve to the form you want, like bottom, railing and maybe the late to be stairs... up to your imagination, or references.
Add a screw modifier and adjust the screw value to make it increase in height, like in your reference picture.
Increasing the Angle and Steps value will make it wrap around the cylinder more often and make it smoother. Consider this though for later editing. The more now the harder time for you later.
Fine tune and adjust and from here you can work either with boolean operations and try to stay non-destructive or apply the modifier and go creative in what ever way you desire.

Here a little visual showcase with a simplified version of the reference picture like result:

[Update:]

As shown/mentioned in the answer from @Robin-Betts, the option to create the cylinder along with the object originally being wrapped around it is there, and in certain cases i would go with that, as it makes sure the geometry is clean and fitting (important here though is to enable Merge Vertices to keep the geometry free from unnecessary double vertices).

Based on the question i believe you were going from a cylinder (not that those usually are hard to create) but maybe you have already some more details on it and don't want to redo your work.

If you have already some cylinder shape, it might be a good idea to adjust the Angle and Steps value to match the cylinder/base objects vertex count. That way the two objects will be easier to connect, be it on vertex and edge level or just visual in case you want them to be separate.


How do you make bullets do damagein the BGE? I cannot figure out how to make bullets (physical bullets, not rays) actually do damage to the enemy (in a first-person shooter).  I have tried the collision sensor but I cant seem to make it work.
All I am trying to do is make it so when the bullet hits the enemy, then the enemy disappears (Edit Object: End Object Actuator).  The enemy has the physic type: Character and the bullet has the physics type: Static.  I am using simple motion for the bullet.
 What kind of properties does the bullet of enemy need if any? What should the logic bricks look like?

Your problem might be that the character is not detecting the collision from a static object. If you make your bullet a rigid body object, with all of the translations locked (rotation and location along X,Y, and Z) as in this picture,

Your bullet will have the same behavior as a static object (It will not fall due to gravity and it will not bounce off of other objects), but the rigid body type can detect collisions with a static object. Another thing you could try is changing the collision bounds on both your character and the bullet to something closer to it's actual shape. Normally, a box will work for the projectile, but for the character you will want something more precise such as a Triangle Mesh


GeForce GTX 760: Unsupported Graphics Card or Driver I recently installed Blender on my desktop to dip my feet into 3D modeling and printing.

The computer has an AMD A10-5800K CPU with integrated graphics, which does not support OpenGL. I recieved the “Open GL 3.3” error when trying to run blender.

I then salvaged a GeForce GTX 760 from another computer and installed it, and installed the newest drivers for the card. However, even though the GTX 760 supports OpenGL up to 4.3, I’m still receiving the 'Unsupported Graphics Card or Driver' error with the “Support for OpenGL 3.3 or Higher is required”.

I’m not sure if Blender is still trying to use my AMD integrated card. I have attempted uninstalling and reinstalling Blender after installing the GTX 760.  I've also disabled the integrated graphics in my BIOS.

Windows 7, 64 bit

I was finally able to figure it out.

Had to go into my BIOS and disable the integrated graphics (again), then completely uninstall the AMD Catalytst Control Center, then uninstall and reinstall Blender again.


How to obtain a sharp corner on smooth surface Hellow everyone,
How can i obtain a sharp corner on the smooth surface of this model?
I am using a subdivision modifier.
Adding a loop edge creates a "break" on the curve (red arrow).
What's the best workflow?
Thanx.

Add another Loop between the two loops and slide it closer to the loop you want to be sharper. Use LOOP CUT tool


2.78b : Blender system Cloud texture addon not showing Just subscribed to Blender Cloud
Downloaded addon: https://cloud.blender.org/services
Able to login via Blender Cloud id(This one was already installed with 2.78b - so dont know why it is included in the download addon)
Install from file. But I don't see any "System Blender cloud texture"

The Blender ID add-on was first bundled with Blender in 2.78; it was included with the Blender Cloud add-on to allow people with Blender 2.77 to use it too.

To get to the Texture Browser, the easiest way is to press CTRL+ALT+SHIFT+A. Alternatively, in the UV/Image editor, choose 'Image' > 'Get Image from Blender Cloud'.

The documentation is available from the add-on screen itself, and describes some of the other features too (like Blender Sync):


Is there a way to make a quick animation PREVIEW, to evaluate motion, etc.? I want to evaluate motion, camera moves, etc., preferably in OGL -- I can't seem to find this in the Manual, and it seems no one has covered it on YouTube (at least I haven't found it if it's there) ... There must be a way to make a quick PREVIEW of the animation that can be viewed in real time, without waiting for the entire render ... If so, HOW?

You can OpenGL render a movie with the 'Render OpenGL' movie button, found in the lower right header of the viewport.

It'll use your regular render settings for frame ranges/formats.  Personally, I like to render a sequence of pngs/jpgs into a temp directory, and then load the sequence in the Sequence editor.  But some people prefer a separate movie player application.


objects don't show up I must've accidentally touched some key because all of the objects except the one i was workin with have dissapeared, and don't show up even with the visible toggle on
Also if i select them they're stuck in Object Mode and I can go to any other mode

Here's the mesh http://s000.tinyupload.com/?file_id=35648957213405038207

My guess is that you pressed / to go to "local object view". Just press it again to show all the other objects.


What should I track for accurate rotation stabilization? Or, how can I stabilize motion timelapse? If I'm taking still timelapse photos of a stationary subject while moving along an arc radiating out from the object, what should I mark to stabilize rotation?

To make the question more tangible, let's imagine a cube. In the middle of the cube there is an X which I can use for the 2D stabilization point. Now I want to stabilize rotation. But the cube's edges are going to undergo perspective distortion as I rotate around. The horizon may not be visible from some perspectives either. So there's nothing in the scene itself to track rotation, but it's obvious upon rendering the animation that there is rotational instability present.

It seems to me almost the only way to do it would be to create a 3D model that corresponds with the 2D timelapse photos and superimpose the 3D cube over the physical cube. Then each frame could be rotated to keep it's perspective consistent with the rotating 3D model. Although this seems like a possible solution, I'm not sure what workflow I would use to achieve it.

EDIT: I've been watching Track, Match, Blend and am learning more about some of the limitations. In the tutorial it was shown how panning motion can't be solved automatically. Perhaps I don't understand enough about the limitations of rotational stabilization. It seems to only work on a 2D plane. But if the camera is moving, either in a straight line or in an arc, is it possible to stabilize rotation?

Rotational stabilisation requires 2 points/trackers that remain stationary relative to each other not the edge of frame or camera.

If that isn't available then your other solution will require a good 3d solve, from lots of trackers. But it sounds like you may not have much to track there either.

Perhaps you could use 2 planar tracks they tend to track features that cover an area instead of a point.


Some Microdisplacement(?) going wrong I had tried to use micropolygon displacement but ended up disabling it.
This is the preview rendered view:

But this is the final render:

What on earth is happening!?

Micro displacement is sensitive to normals.
Make your model smooth (shading smooth) ensure normal continuity across edges.
Doing so will prevent displacement discontinuity on sharp edges.


black edges scatter around my imported mesh I have recently imported my new base mesh for my model from maya. I tried to apply materials but even with the default mat, i could still see through my mesh. this happened with several quads around my model. i went on edit mode in blender and checked the mesh and i saw these unusual black edges in the areas the issue happened. i have no idea how to fix this, i just assume that my mesh has some problems with normal faces. last time i checked my mesh didnt have any overlapping verts or edges. Please help me resolve this problem.

Here's the mesh i just uploaded to blenderexchange:

The black edges are normal edges, while all teal edges have the sharp flag set. So just select all edges, and open the edge menu with Ctrl+E. Select Clear Sharp, or Mark Sharp, depending of what you try to achieve.


Why can't I see my texture in prevew and render view? I have painted in substance painter and imported the texture. I can see the texture in texture mode. When I render or preview render it  the bottom mesh (body skin) is showing just a basic color. The other mesh (antenna) is showing in both texture mode and in render. I have assigned the texture and uv map also. Any suggestion or help why I can't see it?

Texture Mode

Preview Render

Nodes

You have Subsurface scattering set to 1.00 This is a lot, the green color will overwrite the texture. Try a lower value of Subsurface (0.2 or 0.3 would be my guess)


Legacy file in BI: Background image does not change as camera pans I am working on an older file with a background image. In the animation, the camera moves and pans relative to two objects in the scene. But the background image behind the camera and behind the objects looks the same at every point: The background image is not effected by the move/pan.

I know this solution for Cycles:
Add a panoramic background to scene in Cycles

and it performs (in cycles) as I expect: the background image changes as the camera moves/pans... I am unable to recreate this in BI... and clearly I have forgotten something.

All input welcome.

There is mapping option in the world texture setting change it from View to what suits your needs :


Armature doesn't move with mesh My mesh won't move with my armature. I think everything is properly attached, etc. It seems to only happen when I reposition the bones of the armature to correctly fit the mesh. It works prior.

I'm completely new at this, any advice would be helpful. Here is the .blend file.
https://www.dropbox.com/s/rjt2zdv6owtqfst/why.blend?dl=0

They do move together, you just need to click or press enter to confirm and see the change.
If you want to see the mesh move in real time while you are moving it with the armature, disable Delay Refresh in the Display panel of your armature.


Convert vertex instancing to single mesh I have created a simple scene. Here are the steps:

Make a plane and subdivide it a few times
Make a cube
Parent cube to the plane
In Object Properties tab of the plane, under Instancing, I selected verts.

All this did was make a copy of the cube appear on every vertice of the plane. Now I need to use a boolean operation to cut away at multiple cubes. However, I cannot do this because the instances are not actual copies that can be manipulated. Can I transform all of them into a mesh?
Note that in the final result, I will also displace the plane thus displacing the cubes. A simple grid created using array modifiers will not work.

To convert instances into objects, go to Object > Apply > Make Instances Real.
You can then join them into a single mesh using Ctrl + J.


Sort list node is missing in Animation Nodes 2.1.7? I've been trying the expression node with x.sort(key = lambda o: o.name), but it gives no result.
How can I sort objects by name in this situation?

expression sorted(x, key = lambda o: o.name) works well.


Unable to remove unwanted edges after fill So i have a shape:

That i fill:

and after doing a "Limited dissolve" it looks a little better:

But it leaves some edges that are impossible to delete without either deleting the face or messing up the shape, this is what happens if i delete the white edge:

Anyone knows how to fix this?
I have googled and watched a ton of YT tutorials but not been able to figure this out.
Thanks for reading my question and have a nice one!

There is no way to clean all edges in your object. Since blender cant handle holes inside n-gon by one face. You can make nicer topology by manual reconecting some of the edges (or try to search for Beautiful Fill function), but you will need always at least two faces (two edges connected to a hole).

In some cases would be better simply select object and Convert to Curve type 2D. No more additional edges, just outlines.


Message actuator/sensor across scenes? In the BGE, I'm trying to send a message from one scene to an overlay scene. The subject in the main scene's actuator matches the overlay scene's sensor. I've also made sure I'm sending the message to the right object (but also tried leaving it blank - sending to all objects - no luck).

The overlay scene doesn't seem to receive the the message at all. I genuinely do not have a clue of what's going on. I thought you could send messages between scenes. The overlay scene is inactive when sending this message btw. It's going to be an inventory screen that's only visible when player presses I (overlay scene).

The scene has to be active in order for objects within it to receive and process messages.

Instead of removing the overlay scene to hide the inventory, you should just move/rotate the camera to look away at some empty space.


Echolocation visualisation (echosonar) I am working currently on a visualisation of bat's echolocation system. My goal is to make bat sending waves that reveal objects before him. I already tried with wave texture but I can't figure out how to force all object (trees, river, rocks) to have the same uv so the waves point evenly in the right direction

What I get so far

Desired look

Suggestions much appreciated!

If this is the look you are aiming for, unless you need to export this somewhere else, you could achieve it just by using generated coordinates.

Simply use world coordinates for your texture. Start with Object coordinates, then run them through a Vector Transform node from Object to World.

Alternatively, I imagine your bat emitting sound waves will be moving, so instead use an external object as source for texture coordinates, like an empty, then animate its position or parent it to the bat.

In both cases just animate the Color Ramp's position parameter for the stops to achieve the "moving rings" effect.


lines while importing .dae files I imported a .dae file but there seems to appear line like objects (and circles at the end of it) starting out from the center of the world. Can you tell me what they are and can it be removed?

But when I open the same environment (.dae file) in another application, I get a proper environment.

These lines show relations between objects. I think in your case these are parent-child relations, which means that in the bottom left corner there is an object (parent) that, if you move it, moves all the other objects (children) with it.
You can disable that these lines are drawn.
In the Overlays for the viewport you can disable Relationship Lines.

Also have a look at the outliner window in the top right of your screen. It can tell you much about the scene:

If you expand the item by clicking on the small triangle left of the name of the object, you will see the objects that are parented.

If you want to make any of the parented object a completely independent object, then you can select it and press ⎇ Alt+P and clear the parent relationsip.

For Version 2.7
Press N while your mouse is in the 3D viewport to bring up the Properties shelf. Then scroll down to display and disable Relationship Lines:

If you also want to deactivate the transform widget look for the marked button at the bottom of your 3D viewport:

Alternatively you can activate Only Render. Then anything that is not mesh data will be hidden, except for the transform widget.


What is the blendcache_learning folder? Google gives me no results for this folder that appears in my project folder.

Can I delete it?
Can I disable it somehow?
If it's not important why is it not kept in Blender's temporary folder somewhere?

Smoke simulations, and – if "Disk Cache" is selected – also cloth and soft body simulations, will create a folder called blendcache_$file where $file is the name of your .blend file (fluid simulations will create cache_$file instead).

Those folders contain the results of baking the physics. Deleting them clears the bake; to bring your bake around (to another computer) it's necessary to keep those folders as sub-folders of your project.


How can I reflect a transparent background? I'd like to make a glossy surface which reflects objects above it, but that also reflects a transparent background in the final render.

So in effect, the final render would contain only the reflections, not the surface itself.

Is this possible please?

You need to use a Transparent shader, and a Glossy BSDF shader, combined with an Add Shader, not a mix shader.

Using the Add shader gives a perfect result:

Nodes:

Result:

Although you should normally use a Mix shader (greater realism) this is a perfect use case.

Here is a comparison of the two methods:


Best Strategy To Speed Up Work Flow For Repeated Actions I'm finding that I repeat many actions and would like to know what the best strategy is to make those actions easier to do to speed up my work flow.

I'm looking for an answer that makes things geometrically shorter distance to achieve the actions and use less physical energy overall.

For example, is there a plug in I should know about? Should I create a custom mappings for shortcuts? Etc.

If you are willing to do a bit of Python scripting, it actually isn't that hard, assuming that you don't have to do anything that involves modifying specific vertices in Edit Mode. For my example script, I will do these three actions:

Duplicate the object and move it 2 Blender Units in the +X direction,
Scale it by a factor of 2 along the Z axis.
Apply the scale.

You can do whatever actions apply to you.

First, set up the viewport. Split the view and pull up a text editor. Create a new text file and name it script.py. At the top of the screen, hover over the bottom of the Info bar (the one with the File, Edit, etc. menus). Your cursor should become vertical resizing arrows. Drag the Info bar down to reveal the Python Report Console.

Next, we need to set up our Python script. In the text editor, type

import bpy

Now, do the first step of our composite action (in this case, duplicate the object and move it). In the Report Console, you will see a new entry has popped up. Right click it, press Ctrl + C (or Cmd + C), and then paste it into a new line in the text editor. My code now looks like this:

import bpy

bpy.ops.object.duplicate_move(OBJECT_OT_duplicate={"linked":False, "mode":'TRANSLATION'}, TRANSFORM_OT_translate={"value":(2, 0, 0), "constraint_axis":(True, False, False), "constraint_orientation":'GLOBAL', "mirror":False, "proportional":'DISABLED', "proportional_edit_falloff":'SMOOTH', "proportional_size":1, "snap":False, "snap_target":'CLOSEST', "snap_point":(0, 0, 0), "snap_align":False, "snap_normal":(0, 0, 0), "gpencil_strokes":False, "texture_space":False, "remove_on_cancel":False, "release_confirm":False})

Now we just need to repeat that process for the remaining steps. Note: The blocks of code in the Report Console don't automatically deselect. We can use this to our advantage, though and copy and paste multiple lines at once. Once I got all of my code copied to the script, it looked like this:

import bpy

bpy.ops.object.duplicate_move(OBJECT_OT_duplicate={"linked":False, "mode":'TRANSLATION'}, TRANSFORM_OT_translate={"value":(2, 0, 0), "constraint_axis":(True, False, False), "constraint_orientation":'GLOBAL', "mirror":False, "proportional":'DISABLED', "proportional_edit_falloff":'SMOOTH', "proportional_size":1, "snap":False, "snap_target":'CLOSEST', "snap_point":(0, 0, 0), "snap_align":False, "snap_normal":(0, 0, 0), "gpencil_strokes":False, "texture_space":False, "remove_on_cancel":False, "release_confirm":False})
bpy.ops.transform.resize(value=(1, 1, 2), constraint_axis=(False, False, True), constraint_orientation='GLOBAL', mirror=False, proportional='DISABLED', proportional_edit_falloff='SMOOTH', proportional_size=1)
bpy.ops.object.transform_apply(location=False, rotation=False, scale=True)

Now, I can just select the object I want to duplicate, press "Run Script", and Blender performs all the actions I put there. This should work for most workflows.


How can I make animations look more natural? Most of the animations I make are not as "real" looking as other animations I see. My animations can be found here. I want my animation to look like these.

I would suggest that you study the 12 principles of animation closely. Looking at your animations, it's obvious you're not following these; for instance, the ease in, ease out rule. Your camera motions seem to abrupt, too stable. Too unnatural.

And then practice. A lot.

I also recommend the principles of animation series by Dan Floyd from Extra Credits/Play on Youtube, where he covers these principles and show some great implementation of these in games.

You may also want to take some classes in animation, such as Animation Mentor. Keep in mind that any class about animation, even if about traditional drawn animation, will help you master 3D animation.


Unable to use tablet brush pressure I'm using Blender 2.8 but I cannot achieve to use the Wacom tablet pressure in sculpt mode like in other software. Is this a known bug?

Is your tablet's pressure sensitivity working in other applications? If not, here's a potential solution to the pressure sensitivity not working:
https://www.drivereasy.com/knowledge/fixed-wacom-pen-pressure-not-working/

It says to go either go to search "Wacom Tablet Preference File Utility" open that application and click "remove all user preferences. Save your preferences then restart your computer.

You can also try updating your Wacom Driver.


how to copy one gpencil layer from one scene to another scene in the same blender file? how to copy one gpencil layer from one scene to another scene in the same nlender file ?

Try this:

In 3d-view change mode to Edit Strokes:

Then select strokes (for example using A, C or B), then Ctrl+C.

Then move to different scene  create a new layer, set mode to  Edit Strokes and press Ctrl+V.


Mesh not rendered in Blender I tried all answers from Internet, press W - "Clear All Restrict Render", uncheck my post processing - "Compositing", recalculate my UV, Ctrl+N, switching back to CPU render, switch to blender render, etc., none of them works in this case. NOt sure if this is because I import the object from makehuman. My object view, material view and render view attached.

Material view:

Object view:

Who knows any other trick I should try?

From your screenshots, I see that the only light source that is present in the scene is the default point lamp.

It looks like this is not enough to light up your robot. Maybe try changing that to a sun lap, or boost the power of the overall lighting in the World settings.


Anyone else having wrongly named boolean settings? It seems that when I use the boolean modifier it switches the resulting boolean option between difference and union.
This can't be normal right?

I'm using blnder 2.75

This can't be normal right?

Funny, it is because of normal(s). Recalculate surface normals with Ctrl+N in editmode. Also make sure the scale of the object is not negative (apply scale Ctrl+A)

Normals specify what is considered outside and what is considered inside of mesh. Booleans take this into account.


Blender's Sound actuator 3D sound without pitch change I want to use a certain sound in my game, but the object that is using it is moving quite fast. If it passes by the camera the pitch changes dramatically. I know that this is a natural effect, but it's pitch changes way too much. It's not realistic anymore.

Is there a way to either remove the effect or decrease it without changing any other 3D sound setting. I would still like to be able to hear where the object is coming from through my headphones.

I can't remember if it works in the game engine, but this is where you're meant to be able to adjust this (the Doppler box under scene settings)


Is it possible to render part of the composition in eevee and other part in cycles? guys! I want to render this scene (in a video, rotating the camera around the head and the word) but I made the word following a eevee tutorial and the other parts work better in cycles.
Is there a way to render them separately and then join afterwards?
Thanks in advance!

Sure, use two Scenes
You can specify the render engine for each of your scene.

Then in the Render layer node you can specificy the scene to inspect for picking the right view layer.

If you have problems in rendering multilpe scenes at the same time, visit: How do I batch render multiple scenes with animation settings?


Blender OBJ export properties panel missing Sorry for the newbie question. I have this project where I need to export a mesh in obj format, but I can't see the export properties panel (Export OBJ panel):

How can I bring it back?

I think you have dragged down all the way. you will see a small + icon in bottom of properties panel press it, it will come back.


Weight painting on low poly model acts weird i've been trying to weight paint this simple model for a while now because the automatic weights didnt work that well. The images below indicate the places where it went wrong, even though i have duplicated the arms and legs and the opposite limbs work perfectly, those limbs are completely red. As you can see when i weight paint i cant select some vertices without fading into opposite one. If you dont understand my point, heres the link for the blend file:

https://drive.google.com/open?id=11rx-Kgh_FhNLNz8_GN3mrIYPPevsmrno

below are the pictures

You have duplicate vertices in your model, and you are working in opaque mode ('limit selection to visible'), so only one of the duplicates can be selected. Several ways to get around this, one would be to select the vertives you want to work on in edit mode, then switch to weight paint and activate the icon directly to the left of the layer selection block (a cube with one highlighted vertex, "vertex selection masking"). Then you'll be able to only work on the selected vertices (you might need to unselect 'limit selection to visible').

Or you could remove the doubles in edit mode...


Hotkey of Erase in Texture Paint? I found my Wacom eraser could work on Texture Paint.
so maybe there is a shortcut assigning to it?
but I cannot find it in preference

I don't use the eraser on my tablet(mine doesn't come with one) but Texture Paint mode has a mix mode in the brush controls called 'Erase Alpha', and that generally does what you expect in that it seems to erase the paint - BUT if you also then switch to 'Add Alpha', you can then recover what you thought was erased.

I don't know about setting up an operator to swap to the Erase Alpha mix mode and back to the last used brush mix mode, but that might be possible, and then you woudl have to map it to the eraser input. I use an add-on called EZ Paint that enables me to toggle erase/add alpha with a short cut key, but that isn't what you are looking for.


Alpha Transparency not working for mesh in Cycles Render I created a text object and then converted it to Mesh (Alt+C).

What I want to do? Achieve a fade-in animation. Insert one keyframe for transparency when it is fully transparent, and another when the object's opaque.

What's the problem?

I am stuck at the first step. I can't seem to make it transparent. Here's a screenshot:

The transparency works in the solid view but not in rendered mode. If it matters, I have some keyframes related to scale attached to that mesh text object.

I had followed one tutorial that led to me the above step. I have also seen this question Alpha transparency not working but it did not work for me.

Question:

  Why is my method not working?

To render transparency in Cycles you need a transparency shader.

Setup your nodes in this kind of configuration, and set your key frames on the "Fac" value of the "Mix Shader" :


How do I select things behind/near the gizmo? I've looked everywhere but I can't find a way to select things "behind" the gizmo in 2.80. It's like there's a forcefield that gets in the way. I didn't have this problem in 2.7x. Is there some setting that allows me to select through the gizmo so I don't have to keep disabling it while editing?

I had the same problem and the solution is to go to

Edit > Preferences > Keymap then select Drag under Activate Gizmo.

and it should work.


Extruded face has stretched material I have a terrain surface and i extruded it downwards along the z axis. This resulted in the material being stretched at the side. How do I have the sides and bottom to not have any color at all?
I realise I am using 'materials' and 'texture' interchangeably as I m unaware of the differences.

I have tried:

UV editing > Unwrap > Project from view (bounds)
Tweaking material properties, ensuring that it is on 'clip', 'linear', 'flat'

Been trying to solve this and other problems for many weeks now. Any help would be great thank you.

Create a new material for the edges and sides of the object.
With the object selected, go into edit mode. Select all the face that you want to change the color of. Now in the material properties tab, you will see an "Assign" option. With the correct material selected, press assign.


Quick smoke in blender 2.8 goes the wrong direction I tried looking for it everywhere, but I can't seem to find a fix for it.
Maybe I'm making just some really du b mistake but I can't seem to figure out what that would be. I looked everywhere and made node setups for the fire and smoke but they all had the same problem: the smoke and fire are going to the left instead of going up. Please help it has been very frustrating.

You have a wind force in the scene. If you want that to make the smoke go up, scale the domain, and rotate it parallel to the Z axis. Then bake the smoke at whatever your settings are for it, and your problem should be fixed. This problem was caused because the wind blew the smoke across the top of the domain, not up.


Particle system issue - hair moves at the start of animation even without force fields I have a sphere with a hair particle system.
gravity ON, stiffness 2.500, cache start: -200

I tried to play my animation without force field enabled, the particle system is moving (for sure it could be the gravity influence).
How can I see if I set the cache start at -200 the problem is still there or not.

How can I stop this animation and then be able to move the particle system without problems?

I'm not sure if this is what you're asking... but if you move to frame 0 it will reset it, unlike moving to frame 1.

Hope this solves the issue you were having!


emission lights not working as needed in cycles or eevee I have this scene that is finally starting to come together but I can't get the lighting to work properly in 2.79 or 2.80 (Cycles or Eevee).  This is what it looks like in the viewport:

I know the dome needs to be optimized.

This is what it looks like in Evee:

The only lights in the scene are emission objects on the windows.
I also have an environment texture that I am trying to use for "HD reflections". As long as the environment texture is plugged-in, the lightning is the same no matter how many, how few, or how high/low I set the emission shader:

If I unplug that environment texture, the scene is completely black (except for emission objects) no matter how high I turn up the emission shader:

I have ambient occlusion turned off.

The blender file is attached (or would be, if I could find the "attach" button (where'd that thing go?). Can somebody take a look at my settings and help me figure out how I can get my emission lights to be usable? As it is now, I can't use them to properly illuminate the scene. Thank you for your assistance.

Eevee isn't a raytracer like Cycles - lights, reflections, shadows, etc. are effectively 'faked' in order to sacrifice quality for speed. This means that you can get lightening fast renders but does require some 'pre-setup' in order to get the desired results - by way of light probes.

Mesh lights (ie, Emission shaders) produce indirect light and by default Eevee doesn't handle indirect light at all.

For mesh lights you need to use an Irradiance Volume light probe. The Irradiance Volume is a cuboid which encases an area of your scene. It is not rendered itself but Eevee can 'bake' the contents to measure the irradience (emission) within that section of your scene, applying it to any other parts of your scene within that volume.

Within the Render properties in the right-hand properties panel is an Indirect Lighting section and within that a Bake Indirect Lighting button. Clicking this tells Eevee to analyse the indirect lighting (Irradiance Volumes and other light probes) which it can then use to render the scene.


Remove symmetrical sections from model So I want to remove square-like sections from this simple model. I want to remove sections like the ones shown in the pic. Kind of to make it seem like windows. The problem is, I don't know how to remove these sections symmetrically, and I want the sections to be spaced properly.

Which modifiers should I use to achieve something similar?

You could add a cube, use an array modifier on it (set it to 4), then on your plane use a boolean modifier set on Difference and target your cube. It could help to add a subdivision modifier set on simple on your plane too (prior to adding the boolean), in order to get enough geometry for the boolean modifier to work. You could also just have a mirror modifier on your plane and cut it manually, there is a ton of ways to do this :).


Add transition while switching scenes in BGE I'm working on a simple quiz type game as we speak...  Now in my game, if you click on the correct option, it adds to your score and takes you to the next level (i.e next scene).

Problem is, the switch is too abrupt... I'd like to put in a fade in effect or some kind of transition which activates when the correct option is clicked and shows the next scene...

Now there were 2 tutorials on youtube on how to do this but both of them are in German... and that's a language I have no idea about....

Thanks!

There are several options:

A) show a transition animation before leaving the current scene

B) show a transition animation when entering the new scene

C) both A) and B)

D) switch from the current scene to an intermediate scene (showing transition) to the new scene.


Boolean modifier shows object as hollow at the cut out I am trying to cut out a tiny section from object (the red one) using Boolean modifier but when I do that it shows the object as hollow behind the cut out. But when I do the same with let's say Cube added from the Blender menu the cut out is solid - why?
Solutions I found around here talks about using Solidify modifier but that does not solve that for me: it just make the walls thicker but not doing the object solid and does not even respect the cut out shape (it should be like elongated ball as seen below)!
Can anyone tell me how to tell Blender that the cut out section needs to be solid and not hollow?
CLICK HERE FOR TEST BLENDER FILE

I am somehow starting to think maybe it is something with how is the object - LEGO brick - made, tho it is a standard official LDRAW brick repository DAT file imported into Blender, so it should not be the case (or I think it should not be thinking that anyone who made that 3D object known what he/she is doing when it is official brick from LDRAW). So maybe someone willing could look into possible design problems of the brick itself? Just a quick thought tho for those experienced Blender users (not my case).
EDIT
It turns out something unspecified was wrong with my Blender 2.90.1, once I downloaded and installed the newest version (v2.92.0) everything worked instantly as expected...but I will check the right answer anyway as ti basically correctly stated as of what to do to achieve the cut out itslef. :-)

I think your problem was that you never actually applied the modifier before deleting your carving object. Otherwise, as you can see, after I deleted your modifiers to restart with a fresh one, I could achieve the desired effect. I hope this helped.
EDIT:
Here's a .gif of the procedure:

delete the pending modifiers
create a UV sphere (scale it down and drag it around)
create a new modifier
apply it
delete the sphere


I am unable to extrude this plane along z-axis.Why? I saw in youtube video a guy extruded a plane along the z-axis but I couldnt do it.

Going from what you already have selected, all you have to do is press E. Blender will automatically start the transformation locked to the face normal, which in your case is along the global Z axis.

As lemon pointed out in the comments, from the view in your screen shot (orthographic view) you will not be able to perceive any change in height.


Exported animations missing keyframes? So I'm exporting an animation. The devs on my team want a delay/idle at the end, so I simply copied the keyframes of the last frame of the animation.
But when exported its doesn't show up?????????? I'm using the default fbx export with no changes at all to the settings.

Found out that the "simplify" in the export options(fbx) seems to remove the keyframes. Exported the mesh with that option turn off, exports with the keyframes correctly.


How do I render only the particular view layer I want instead of always including a full composite pass? I have a scene and I'd like to render out PNG layers to make life easier in post-production. I have set up all my layers to render separately. However, Blender is also spending time rendering out a composite of all layers even though I only have the following node setup:

Note that there is no composite setup, but I still get one. It's adding a lot of extra time to my render.
Thanks for your attention.

Okay, I figured out the answer:
Under RENDER and VIEW LAYER, make sure that Use for Render is UNCHECKED. This will eliminate that particular layer. In the compositor, plug in the the layers that you want to export per my initial graphic. Or, select the checkbox for Render Single Layer (while making sure you are actually on that layer).


How can I make this airfoil/wing with the help of a Bezier curve without having to turn it into a mesh in Blender 2.79b? Is there a way I can turn this airfoil here, into a wing?

I made the wing by converting the curve into a mesh, and then extruding it, but of course I lost the very useful handes of the curve.

How can I make the same wing, without having to convert the curve into a mesh?
I need to extrude the curve but, when I do it using the right hand side panel, it just extrudes it into uniformally, without giving me more handles alongside it to be able to change its shape along the way.

I know I can always turn it into a mesh, the way I did it for the wing in the image but keeping it a "curve" with its handles would be desirable in the long-run.

Unfortunately you cannot model complex shapes in Blender using curves(with handles) only without any add-ons. It is possible to use NURBS, but NURBS surface curves do not have handles on their points.

There is however an add-on Animation Nodes that provides more procedural modelling functionality and you could construct a surface out of curve splines using loft function. This way you could keep the curves and their handles that influence the shape of the surface. These would be the nodes needed:


Eevee volumetrics different in render When I was trying to make a cloud in Blender, I began to notice a strange issue. When the cloud is rendered using Eevee in the viewport, it looks fine. But when I render it, it looks much more transparent than the cloud in the viewport, as well as seeming very unrealistic. The cloud is made with a procedural shader.

Viewport Render:

Actual Render:

As you can see, the actual render is many times more transparent and also looks very "blocky" if you know what I mean.

You are correct volumetrics are a bit different in EEVEE. For some reason, emission strength is required to control the volume. As you can see, I upped the emission strength, then plugged the volume into the emission color, to make it constrained to the cloud. Have a try. You might need to  play with the values a little to get it just right in your scene, but it's a start.


How can I combine two displacement without the face normal changes of one screwing up the other? I'm looking to apply an animated displacement to a surface which has already been displaced with a cloud texture (creating an organic lumpy base surface).

It should look like this...

...applied to this...

...but instead it looks like this:

Source files here and here.

The problem is that the normals changed by the first displacement completely screw up the second displacement (I think).

Does anybody know how I can achieve the double displacement of my dreams? I think I need to find a way to redirect the surface normals after the first displacement, but I'm open to any suggestions from you wonderful people.

I was able to achieve the effect I desired by using the Warp modifier after a displace modifier to provide initial organic displacement. Performance in Blender was much slower, but as I'm baking the results this was a non-issue.


Problem to create background in language other than English in the settings This is a script part that creates a background, i i run that in Blender with language default (English) run ok , but if i change for example in Spanish
line 3 give error KeyError: 'bpy_prop_collection[key]: key "Background" not found' , because "Background" is translate to "Fondo".
Now i have not intention to translate all name for all languages, exist simple way to change that script to make work in another languages?

1- new_world = bpy.data.worlds.new('My background')
2- new_world.use_nodes = True
3- node = new_world.node_tree.nodes['Background']

Default nodes are in same order

Since you are looking at the default nodes created when setting a world to use nodes, then the zeroth item is the output node, and the first the background node.

Simply reference them on creation, rather than using a key.

>>> nw = bpy.data.worlds.new("xxxx")
>>> nw.use_nodes = True
>>> nw.node_tree.nodes[:]
[bpy.data...nodes["World Output"], bpy.data...nodes["Background"]]

>>> output, bg = nw.node_tree.nodes
>>> output
bpy.data...nodes["World Output"]

>>> bg
bpy.data...nodes["Background"]

To translate

To find what blender translates from the english to the currently set locale,

>>> bpy.app.translations.locale
'es'

>>> nw.node_tree.nodes[:]
[bpy.data...nodes["Entorno"], bpy.data...nodes["Fondo"]]

>>> bpy.app.translations.pgettext("World Output")
'Entorno'

>>> bpy.app.translations.pgettext("Background")
'Fondo'


Bezier points not at expected location I have following little script, fetch the points from the bezier and add a Null object at each point.
from bpy import context, data, ops

bez_curve = context.active_object
bez_points = bez_curve.data.splines[0].bezier_points

for p in bez_points:
    new_obj = data.objects.new('spline_point', None)
    new_obj.location = p.co
    context.scene.collection.objects.link(new_obj)

But the Nulls I create at each point is placed in what looks like random locations. Total of 4 points added to the Bezier. I have obviously missed something here!

Curve coordinates p.co are local coordinates.
Use the curve world matrix to transform them to world coordinates:
from bpy import context, data, ops

bez_curve = context.active_object
bez_points = bez_curve.data.splines[0].bezier_points
world_matrix = bez_curve.matrix_world # Get the matrix

for p in bez_points:
    new_obj = data.objects.new('spline_point', None)
    new_obj.location = world_matrix @ p.co # Use it to transform coordinates in world coordinates
    context.scene.collection.objects.link(new_obj)