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shengdan
02-15-2009, 03:46 PM
I'm fairly new to the OpenGL API, and I just have a quick question. I need to redraw a particular portion of a frame in the corner of the window (not altered, but just a portion). After all the objects and textures are drawn and the framebuffer is completely filled, I would like to simply redraw part of the framebuffer in the corner of the viewport. I have already implemented it to where it simply redraws the part of the scene in the corder, but it is really inefficient.

I was wondering if there was a quick way to simply redraw a portion of the framebuffer in a different viewport, or something fast that wouldn't require redoing all the calculations that went into drawing the frame in the first place.

I am using OpenGL ES 1.1 if that's important.

Thanks!

scratt
02-16-2009, 03:33 AM
I think I answered this on GameDev already..

I would render the scene to a texture in an FBO, and then you can render it to the screen using a QUAD (or Triangles in ESs case), and then render to anywhere else as many times as you like in any size or sub-section..

shengdan
02-20-2009, 10:36 AM
I believe you did, but I appreciate the answer. Looks like it's going to work fine.

scratt
02-20-2009, 10:45 AM
Cool. Glad it helped. :)