How many maximum triangles can be drawn on ipad using opengl es in 1 frame?

Question

How many maximum triangles can be drawn on ipad in a single frame. Also, is there a limit to the number of gl calls used to draw those triangles?

Answer 1

The only limit on total triangles that you'll run into on the iPad is in terms of memory size and how quickly you wish for this to render. The more vertices you send, the more memory your application will use, and the slower it will render.

For example, in my benchmarks I was able to push over 1,800,000 triangles per second on an iPad 1 using OpenGL ES 1.1 smooth shading, a single light source, geometry stored in vertex buffer objects (VBOs), and vertices represented by GLshorts in order to minimize total size. The iPad 2 is significantly faster than that, especially when you start doing more complex operations in your fragment shaders. From that number, I can estimate that I'd want to have fewer than 30,000 triangles in my scene geometry if I wanted to render at 60 FPS on the iPad 1.

OpenGL ES 2.0 shaders make things more complicated because of their varying complexity, but they enable new effects and may allow you to use fewer triangles to achieve the same image quality as the fixed function pipeline.

For another example, in this question Davido has a model with about 900,000 triangles that he's able to render at nearly 10 FPS on an iPad 2. I also present some geometry optimization techniques in my answer there that I've found to have a significant impact on OpenGL ES 1.1 rendering when you are maxing out tiler utilization on the device.