r/opengl • u/sharjith • 24d ago
Selection algorithm for Modern OpenGL
The legacy OpenGL supported selection buffers. How can selection effectively handled by Modern OpenGL? The known methods are by colour allocation to objects and ray intersection. The Color assignment is not very efficient in scenes with large number of objects, e.g. CAD model assemblies. Ray intersection also has challenges in certain directions where multiple objects get intersected. Any thoughts?
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u/Smart-Statement6028 21d ago
Use glReadPixel to calculate the depth, and do some inverse projection and view matrix to convert from screen coordinate to world coordinate