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I am quiet new to opengl stuff but still have a little sense of opengl es 1.x and 2.x

GLPaint is a opengles1.x sample to draw with finger. As we know OpenGL ES 2.0 is quite different with ES 1.x, my question will be is that feasible to implement the GLPaint with OpenGL ES 2 and iOS 5 opengl classes ? If yes, in terms of performance, is that better or worse ?

genpfault
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Forrest
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1 Answers1

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It's perfectly feasible, but I'd not do it. GLPaint is a terrible program for a tutorial.

If yes, in terms of performance, is that better or worse?

For that program you'll not notice any difference.

datenwolf
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  • Thanks first. But why GLPaint is a terrible program ? So since no big difference from performance, any foreseen improvement with OpenGL ES 2 from your understanding ? – Forrest Mar 12 '12 at 04:01
  • @Forrest: GLPaint does things in a very special way and the OpenGL usage patterns it uses make very little sense for other OpenGL programs. For example it draws directly on the screen framebuffer. A common request is, adding backgrounds, or undo redo functions. Effectively you're jusr moving a single quad with some texture over the screen, modifying the framebuffer fragments below it. The key functionality of the GPU used is the **blending** stage, and that remains hardwired. A shader could add procedural brushes, but it's still just a quad. And modern GPUs translate fixed function to shaders. – datenwolf Mar 12 '12 at 11:21