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How to use a timer inside a vertex shader to animate point sizes in OpenGL
I'd like to implement an animation effect in OpenGL where my point primitives shall vary in size and transparency over time, based on a value associated with each vertex. This data is stored inside a VBO and passed to a vertex shader.
The whole process of how such an animation effect could be achieved is unclear to me, so I hope to get an answer that describes how animation can be done and what steps are necessary.
I've asked this question before but didn't get a satisfying answer, which is why I post this question again: a link to the previous question can be found here
I'm using OpenGL 4.2 and I would be more than happy if you could tell me how to render a single point in space which varies in size and alpha value!