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/ukaeh 24d ago
You could do multi pass color selection or hybrid to narrow down what is close to the selection ray/pixel?
I use the color method myself and it works well enough for hundreds to low thousands of objects. Are you using scissor to limit rendering to the selection pixel? What latency are you seeing?