Tag: Python

Blender Python API autocomplete modules: fake-bpy-modules by Nutti update – added branch for Blender 2.91.

Last release: 2020.12.16.

Author GitHub: https://github.com/nutti/fake-bpy-module

Only files (without pip installation) https://github.com/Korchy/blender_autocomplete

The camera angle ​​in Blender can be set both in millimeters – the Focal Length parameter, and in degrees – the Field of View parameter.

To get the Field of View in degrees from the Focal Length value in millimeters, we can use the following formula:

Continue reading “How to get camera FOV in degrees from focal length in mm”

We can access vertex groups for the active mesh through its “vertex_groups” structure.

Continue reading “How to create a Vertex Group and add vertices to it with the Blender Python API”

To make a new UV with the Python API and set coordinates to its points, we need:

First – create a new UV with the desired name:

Next, to specify the coordinates of its points, we need to cycle through all the “loops” of the mesh: Continue reading “How to create a new mesh UV with the Blender Python API”

You may need to get a list of coordinates of the mesh’s UV, for example, when exporting a mesh from Blender’s internal format to any external formats.

A list of the mesh UV-s can be got by accessing the “uv_layers” structure:

Continue reading “How to get a list of UV coordinates”

To completely remove the object from the scene through the Blender Python API do the following:

Open the “Text Editor” window.

Continue reading “How to delete object from scene through the Blender Python API”

To add an operator to the area header, we can use the “append” and “prepend” functions specifying in its parameters the drawing function of the operator call button.

For example, to add an operator of adding the default cube to the header of the viewport (3D View) area, we need to define the operator drawing function:

and add it to the window header:

The operator button will appear in the header of the viewport window.

Now we can view a list of all the functions that add operators to the area header by the “_draw_funcs” property of the “draw” method.

Note that the “_draw_funcs” property would be defined only if custom operators have been added to the area header. If custom operators were not added to the header, an error will be thrown:

AttributeError: ‘function’ object has no attribute ‘_draw_funcs’

To create and add a camera to the scene with the Blender Python API we need to do the following:

1. Create a camera data-block

2. Create an object and link it with the camera date-block, we created

3. Add created camera-object to the scene

A new camera will be created in the current scene in its main collection.

Final code:

The Blender Python API provides the ability to append or link objects from another *.blend file to the current scene using the “append” command.

To append an object (for example – a mesh) from another .blend file, we need to do the following:

Continue reading “How to append an object from another blend file to the scene using the Blender Python API”

Blender Python API autocomplete modules: fake-bpy-modules by Nutti update – added branch for Blender 2.90.

Last release: 2020.08.12.

Author GitHub: https://github.com/nutti/fake-bpy-module

Only files (without pip installation) https://github.com/Korchy/blender_autocomplete

In scripts and add-ons for importing-exporting files with formats that are not supported in Blender by default, we must give the user an ability to select files using the “FileBrowser” interface.

To open the file browser window, and after the user selects the necessary file, to return the path to it, we need to use the “ImportHelper” and the “ExportHelper” classes.

Continue reading “Using the FileBrowser interface window to opening and saving files”

To add custom mesh to the scene through the Blender Python API we need to do the following:

Open the “Text Editor” window.

Continue reading “How to create mesh through the Blender Python API”

For add-ons developing, sometimes it is necessary to use packages that are not included in the core set of the Blender Python interpreter. Most often, the dependencies you need are included in the Python Package Index (PyPI) and can be installed to Blender through the Pip package management system.

The Pip Package Manager is already installed in Blender. However, Blender does not allow us to install the desired packages in a common way with the “pip install package_name” command.

Continue reading “How to install required packages to the Blender Python with pip”

Blender Python API autocomplete modules by Nutti update – added branch for Blender 2.83.

Last release: 2020.07.24.

Author GitHub: https://github.com/nutti/fake-bpy-module

Only files (without pip installation) https://github.com/Korchy/blender_autocomplete

For objects rotation, we can use the “rotation_euler” property. This property is a list of three items, each of them corresponds to the rotation angle around the X, Y, and Z-axis. The otation_euler[0] contains the rotation angle around the X-axis, rotation_euler[1] – around the Y-axis, and rotation_euler[2] – around the Z-axis. To rotate an object we must set a rotation angle to the appropriate field of the property.

For example, to rotate an active object around the X-axis to the 90 degrees angle we must execute the following command:

math.radians is used to convert degrees to radians.

The flat/smooth shading mode is regulated through the “use_smooth” property of each polygon of the mesh.

To enable smooth shading we need to set the “use_smooth” property of each mesh polygon to “True”.

For active object:

To enable flat shading – set the “use_smooth” property of each polygon to “False”.

To make new shading mode visible – force update mesh data:

To switch to the view from the active camera we can execute the following command:

This operator works in the toggle mode, so the next executing of the same command returns the view to the previous state.

Continue reading “Switching to the view from camera throug the python API”

To switch from a global coordinate system to a local coordinate system of an object, we need to multiply the global coordinates by the inverted matrix of an object:

To switch from the local coordinate system of the object to the global coordinate system, we need to multiply the local coordinates by the matrix of an object: