1
vote
1answer
253 views

iOS: OpenGL ES 2.0 render texture with glScissor performance

I have drawn image with OpenGL and will redraw tile of its texture (non filled area). Which case will work faster? Set glViewport with full texture's rect, draw full texture and use glScissor ...
0
votes
1answer
125 views

Timing Calculations for Opengl ES 2.0 draw calls

I am drawing a cube in OpenGL ES 2.0 in Linux. I am calculating the time taken for each frame using below function #define NANO 1000000000 #define NANO_TO_MICRO(x) ((x)/1000) uint64_t getTick() { ...
1
vote
2answers
402 views

OpenGL ES - DrawCalls count - bottleneck?

I am newbie to OpenGL ES (so far, I used mainly DX11). Now for my scene, I have about 100 draw calls. I can use instancing, but only about half of objects can be instanced, so draw calls count would ...
8
votes
1answer
519 views

GL ES: Fragment shader optimization

Summary: I get FPS slowdown as soon as I try to tint the sprites (i.e: multiply texture with color in the fragment shader) Details: Hardware: iPod touch 4 I am drawing 700 sprites on the screen ...
3
votes
2answers
1k views

OpenGL ES 2.0: 2D game rendering, no performance gain with glDraw call batching

I just did a small benchmark. To my surprise batching sprites into a single draw call doesn't give any significant performance boost. Following are my results: Hardware: iPod touch 4 Extra info: ...
0
votes
1answer
358 views

Drawing more that one quad with only one glDrawArray call…?

Edit After initially thinking that my sprite batch test was faster than calling each sprite individually, it appears that is not the case!! :-( With a single set of GL calls for a each sprite, I can ...
-1
votes
1answer
107 views

GLES2 rendering performance for different iPad generations

I'm using C++/GLES2 for iPad only (no iPhone). The only device I own is an iPad2 and I do not plan to support iPad 1. Can anyone help me understand realistic goals/limits on iPad 2/3/4 in terms of ...
3
votes
1answer
555 views

Can glTexImage2D() use an already existing memory block?

Can I use glTexImage2D() and / or glTexSubImage2D() (or maybe there's some other method I don't know about) with an already existing block of memory, instead of always uploading the changed pixels? I ...