OpenGL dynamic Vertex color attributes and Texture Coords.

Performance Tuning
#1

Okey guys… I really have a problem…
Consider a blocky world. That world is 2D, and there is lighting.

That lighting is applied as vertex-color attributes. That way I archieve nice-looking interpolated lighting.
The problem with this is following:

I use Immediate mode.
Problem with other modes are:

  • VBO: I don’t want to create a new Mesh for every 40963232*2 block…
  • One VBO: Impossible… I need to have 16*4 different Texture coords…
  • 16 VBO’s: Impossible too, I need to have dynamic lighting… that means, I need to have non-predictable, 10.000+ different light values for each corner of the sprite/quad.
  • VAO: Slower… maybe due to very much dynamic traffic with the FloatBuffer?

Have you got any ideas?

Currently:

  • the vertices are dynamic for every block, to avoid matrix calculations.
  • the texture coords are dynamic, due to Packed “Sprite batches”.
  • the colors are dynamic, due to lighting…

That means, currently EVERYTHING is dynamic.

I think point 1 (vertices) and 2 (texture coords) can be avoided, enabling Matrix transformations, and creating 16 different VBO’s/whatever for every sprite in the sprite-sheet/batch.

But colors are tricky… can you help me? have you got any Ideas???

#2

Use simple vertex arrays (like LibGDX’s SpriteBatch). My sprite batch looks like this (its very messy at the moment but it will give you an idea).
http://www.java-gaming.org/?action=pastebin&id=93

For better performance you could look into mapped VBOs. And if it’s supported in the driver you should look into instancing (unfortunately not supported on my system…).