Questions tagged [python]
Python is an object-oriented programming language. In Blender, it is used as a general purpose scripting language and to create add-ons to extend Blender's functionality.
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How can I run blender from command line or a python script without opening a GUI?
I'm interested in using Blender for producing images, 3d files, or calculating geometry on a server.
Can I make blender run a python script without opening a GUI?
If not, can I incorporate Blender's ...
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8
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Where does console output go
I'm trying to debug a Python script by placing a print("foo=" + foo) statement in my code.
But where does the output appear?
It doesn't appear on the Python ...
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How can I quickly generate / create a large city without modeling it all by hand?
I am trying to create an urban open-world environment in Blender that would be about one square kilometre in size. To avoid having to model hundred of individual buildings, I am looking for a way to ...
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Is there a tool for scientific visualization using Blender?
Is there an interface or API that allows using Blender as a tool for mathematical and scientific visualization? It should allow Blender to read in data (a la gnuplot or matlab, perhaps using scipy) ...
- 802
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9
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Using 3rd party Python modules
I'm currently developing a script for Blender to handle Mesh Frequency Decomposition.
The script is nearly complete, but i need one more thing: The SciPy library to compute eigenvalues and ...
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5
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How to pass command line arguments to a Blender Python script?
Let's say we have a Python script my_script.py that does some data processing with Blender. This script accepts some arguments (e.g. ...
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How to create a custom UI?
I was watching this video on making a custom UI tab using Python, and in the line from bpy.types import Menu, Panel, UIList, I see the names of objects that look ...
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Python: How to completely remove an object
How can I completely remove an object (for example a camera) using python scripting?
Using something like:
scene.objects.unlink(camera)
Does not work, since it ...
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2
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poll() failed, context incorrect? - Example: bpy.ops.view3d.background_image_add()
I keep on getting context errors in the Blender Python API.
I don't understand the issue of the context in the API, how do I know which is the correct context?
Thanks!
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3
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Selecting an object via scripting?
As shown below, I have 2 nested spheres, each with a different material (inner = "1", outer = "2"). Ultimately, I need to select the inner sphere (material "1") via ...
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Custom trackpad pan/zoom/rotate behavior add-on
I'm trying to write an addon to customize the trackpad panning, zoomimg, and rotating gestures, but can't find a way to read the actual trackpad parameters for position and so on. The properties in ...
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Control Cycles/Eevee material nodes and material properties using python?
How can I define the different properties of an Cycles/Eevee material? Such things as glossy, glass, diffuse, RGB-color, emissive via python scripting?
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How to install Pip for Blender's bundled Python?
Blender comes with Python, and includes a stand-alone Python executable.
However pip is not part of the official Python distribution so it needs to be added separately.
How do you setup ...
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38
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1
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How to assign a new material to an object in the scene from Python?
How can I assign a new material to an object in the scene via Python?
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Python performance with Blender operators
In my script, I have for loop over many cube objects (~1000) and the treatment is very slow. Looking more in details, I notice that in the same amount of loops:
if ...
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2
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How to get the directory of open blend file? (from Python)
What's the best way to get the full directory of the current Blender file in Python?
It should be cross-platform.
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Can I run a Python script step by step in Blender?
Can I run a python script step by step with normal blender, a build, external software or an addon?
I'm developing a script (town generator) and I want to to execute the code step by step like a ...
- 3,263
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4
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Why avoid bpy.ops?
Simple and maybe stupid question:
I was reading this lot of time, that
"you should avoid using bpy.ops, or "instead of ...
- 1,919
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3
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Is the Blender GUI package available for other programs?
I really love the look of Blender's built-in GUI, and would potentially like to use these tools in some of my other Python applications. As I understand it, Blender created all of these tools from ...
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1
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What do operator methods do? (poll, invoke, execute, draw & modal)
I've seen the functions called poll and invoke used in scripts. I'm curious what these are for and when they are called.
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How can I get vertex positions from a mesh?
I want to read the vertex x and y coordinates with a script or a function.
How can I do that?
The MeshVertex
appears to have ...
- 1,220
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2
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Is it possible to create image data and save to a file from a script
I'm currently trying to extract textures from a binary file, and ideally I'd like to save each texture to a file or embed in the .blend file. However, before saving ...
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Python: Selecting object by name in 2.8
The following:
bpy.data.objects['Cube'].select = True
bpy.context.scene.objects.active = bpy.data.objects['Sphere.017']
don't work in Blender 2.8, they did in 2....
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9
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Efficient way to get selected vertices via python (without iterating over the entire mesh)
What's the best/fastest way to construct a list of selected vertices for a mesh object in python?
I want to avoid iterating over every vertex in the mesh if possible, since that seems like a really ...
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1
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Blender 2.8 API, python, set active object
I'm trying to amend an addon that I made for Blender 2.7X to work with Blender 2.80.
The problem is with
bpy.context.scene.objects.active = some_object
This is ...
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27
votes
1
answer
9k
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How to implement custom icons for my script/addon?
Is it possible to use different icons other than the default set and how?
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1
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1k
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Closing "Fibonacci's Hole"
Creating a sphere using the points defined by Spherical Fibonacci Mapping. For the most part it is easy to "skin" by using two consecutive fibonacci numbers as steps to loop on the index. And get ...
- 82k
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votes
1
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Property Panel Custom Popup Menu when user presses hotkey over an input field
is it possible to trigger this kind of menu:
in the property panel when I press a hotkey over a button/input field? I want to specifically,when the user presses a specific hotkey when over an input ...
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13
answers
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How can I add a cube?
I am trying to add cubes to my scene. I'm sure there are lots of ways to get a cube into the scene (but for the purposes of this question, I have no idea what they are) - Are there any ways to add a ...
24
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4
answers
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How to show to the user a progression in a script?
I'm making an python script which create a lot of object and this could take a lot of time. My question is how to show to the user of my script, the "progression" of the script?
For now I print an ...
- 3,263
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1
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Create an interface which is similar to the material list box
How can I make a Interface which is similar to the Material-Interface within Blender via Python?
It should look like these. Could you guide me to the right direction? I don't think it's in bpy.ops, ...
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TypeError: Element-wise multiplication: not supported between 'Matrix' and 'Vector'
Blender 2.8 produces the following error whilst multiplying a combination of matrices and vectors
...
- 82k
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votes
3
answers
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Is there a way to restart a modified addon?
I'm currently twiddling with an old addon and insert some print statements for debugging. Currently I'm restarting Blender each time to see the new messages. Is there a way to 'refresh' an already ...
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How to build Blender as a Python module?
I have seen this question now many times and every question here and on other forum points to build blender as python module experimental tutorial by ideaman42. Now sadly a lot of answers are invalid ...
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How to know which object is using a material
How to know which object is using a material.
I know that a material is used 4 time -> picture under:
I'm searching a solution with python and I'm blocked here :
...
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3
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Quick way to get current opened filename in a script?
I'm looking for an efficient way to get the current .blend file name, in a python script.
I know how to get its path, with ...
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4
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Add Nodes to Material with Python
I have edited a script that creates some nodes, but the only problem is, it always created a new material. I want it to either add the nodes on the existing material, or a pre-defined material. Here ...
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2
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Blender UI Multithreading Progressbar
The following question might've been asked several times, but I've found no satisfactory answer.
Short question:
How can I show progress of background task in Blender UI?
Explanation:
I have a ...
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votes
3
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17k
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Pointing the camera in a particular direction programmatically
I'm trying to use Python to place a camera. I know the camera's location, and the forward and up vectors for the camera (i.e. the direction it's pointing and its orientation). How do I do this?
I ...
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5
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How to set cursor location, pivot_point in script?
I am trying to set a cursor location and pivot point with
bpy.types.SpaceView3D.pivot_point='CURSOR'
bpy.types.SpaceView3D.cursor_location = (0.0, 0.0, 0.0)
and ...
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2
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Blender sets Compute Device (CUDA) but doesn't use it for actual render (on EC2 GPU Instance)
I'm trying to set up some automated render servers on EC2 using their GPU instance type (g2.2xlarge). I'm running blender in the background with a python script that renders the image I want and saves ...
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2
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How to make a dynamically expanding menu in Blender?
Say we want to navigate a tree structure without knowing all the data ahead of time, is it possible to do this in Blender?
For example, a menu which dynamically loaded a directory hierarchy from the ...
- 46.1k
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How to convert coordinates from vertex to world-space?
How do I convert from object-space to world-space?
I suspect it is:
vert_os = obj.vertices[foo]
vert_ws = vert_os.getPositionFromMatrix(obj.matrixWorld)
but ...
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Importing python modules and text files
I am new to blender, but not python, and have been asked to create a user-input dependent, stylized animation of a protein network I am working with:
text document >> information processed by python-...
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Where can I find what version of python is bundled with certain Blender versions?
The question is where I can reliably find the information on which python version is bundled with a certain Blender release (like 2.72b at the moment)?
I need to find the major and minor version ...
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Convert Curves to Grease Pencil?
I'd like to know if there's a way/add-on to convert curves to Grease Pencil strokes? I know you can convert in the other direction, but I can't find anything to create Grease Pencil strokes from ...
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How to access Render Result pixels from python script?
Render Result exists in bpy.data.images["Render Result"] but it contains no data.
Also bpy.data.images["Render Result"].size[0] ...
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Which modules are guaranteed to be present in Blender's Python?
Which modules are guaranteed to be included in Blender's custom Python build?
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Is there anyway to make blender print errors in the UI?
For some reason, sometimes error messages encountered while scripting are not printed in the info panel, only the message ...
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How to join objects with Python?
I try to do this:
bpy.ops.object.select_all()
bpy.ops.object.join()
in my script. It selects all the stuff like CtrlA but fails on ...
- 1,919