OpenGL: Single vertex attribute for multiple vertices?

Question

I have a vertex shader that accepts the following attributes:

• a_posCoord: vertex position
• a_texCoord: texture coordinate (passed

Answer 1

I haven't looked into this in detail but I think you could possibly also use glDrawElementsInstanced. With this you would put your alpha values into a big uniform array and the instance index would somehow be passed to the shader. Check this out:

http://sol.gfxile.net/instancing.html