Fixed bug #1026 Vittorio Giovara 2010-07-16 19:09:28 PDT i was reading SDL_renderer_gles and i noticed that every time we there is some gl call the gl state is modified with a couple of glEnableClientState()/glDisableClientState. While this is completely fine for desktops systems, this is a major performace kill on mobile devices, right where opengles is implemented. Normal practice in this case is to update the glstate once, keep it always the same and disable/enable other states only in very special occasions. On the web there's plenty of documentation (on the top of my head http://developer.apple.com/iphone/library/documentation/3DDrawing/Conceptual/OpenGLES_ProgrammingGuide/Performance/Performance.html#//apple_ref/doc/uid/TP40008793-CH105-SW5 ) and i personally tried this. I modified my code and got a 10 fps boost, then modified SDL_render_gles and shifted from 40 fps to 50 fps alone -- considering that i started from ~30fps i got an 80% performance increase with this technique. I have attached a dif of my changes, hope that it will be included in mainstream.

#define picture_width 32
#define picture_height 32
static char picture_bits[] = {
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x18, 0x80, 0x01, 0x18,
   0x64, 0x6f, 0xf6, 0x26, 0x0a, 0x00, 0x00, 0x50, 0xf2, 0xff, 0xff, 0x4f,
   0x14, 0x04, 0x00, 0x28, 0x14, 0x0e, 0x00, 0x28, 0x10, 0x32, 0x00, 0x08,
   0x94, 0x03, 0x00, 0x08, 0xf4, 0x04, 0x00, 0x08, 0xb0, 0x08, 0x00, 0x08,
   0x34, 0x01, 0x00, 0x28, 0x34, 0x01, 0x00, 0x28, 0x12, 0x00, 0x40, 0x48,
   0x12, 0x20, 0xa6, 0x48, 0x14, 0x50, 0x11, 0x29, 0x14, 0x50, 0x48, 0x2a,
   0x10, 0x27, 0xac, 0x0e, 0xd4, 0x71, 0xe8, 0x0a, 0x74, 0x20, 0xa8, 0x0a,
   0x14, 0x20, 0x00, 0x08, 0x10, 0x50, 0x00, 0x08, 0x14, 0x00, 0x00, 0x28,
   0x14, 0x00, 0x00, 0x28, 0xf2, 0xff, 0xff, 0x4f, 0x0a, 0x00, 0x00, 0x50,
   0x64, 0x6f, 0xf6, 0x26, 0x18, 0x80, 0x01, 0x18, 0x00, 0x00, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};