Interactive volumetric 3D images with transparency from .VTI/.VTK files

Coding
1

I would like to create an experiment in PsychoPy that uses volumetric 3D images as stimuli and allows participants to rotate and zoom in/out on them interactively.

This is not my video, but we are also working with 3D images of luggage, and this is exactly the kind of thing I would like to achieve in PsychoPy: https://www.youtube.com/watch?v=EslqbxdbDWc

I’ve seen that there is now the functionality in PsychoPy to load up wavefront .OBJ files, but these don’t allow for the transparency that I require (it’s important that participants can see through the 3D volume to the objects located within). The images I have are currently saved as .VTI files, but are essentially just a structured 3D grid of data points that I’m able to manipulate in NumPy.

Does anyone know if this is possible in PsychoPy?

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Paging @mdc as our resident 3D expert!

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Hello amr,

Volumetric rendering as described is actually pretty tricky to do without custom GLSL shaders. PsychoPy does not come with support for volumetric rendering, but does come with tools to help get custom shaders working. This will require an advanced knowledge of OpenGL to accomplish.

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Thanks for the explanation and reply!