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copied!<p>You can use the view's layer property to get the CALayer and use renderInContext: on that to draw into a CoreGraphics context. You can set up a CoreGraphics context with memory you allocate yourself in order to receive a pixel buffer. You can then upload that to OpenGL by the normal method.</p> <p>So: there's a means to get the pixel contents of a UIView and OpenGL will accept pixel buffers. There's no specific link between the two.</p> <p>Coding extemporaneously, the process would be something like:</p> <pre><code>UIView *view = ... something ...; // make space for an RGBA image of the view GLubyte *pixelBuffer = (GLubyte *)malloc( 4 * view.bounds.size.width * view.bounds.size.height); // create a suitable CoreGraphics context CGColorSpaceRef colourSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef context = CGBitmapContextCreate(pixelBuffer, view.bounds.size.width, view.bounds.size.height, 8, 4*view.bounds.size.width, colourSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big); CGColorSpaceRelease(colourSpace); // draw the view to the buffer [view.layer renderInContext:context]; // upload to OpenGL glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, view.bounds.size.width, view.bounds.size.height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixelBuffer); // clean up CGContextRelease(context); free(pixelBuffer); </code></pre> <p>That doesn't deal with issues surrounding non-power-of-two sized views on hardware without the non-power-of-two texture extension and assumes a suitable GL texture name has already been generated and bound. Check for yourself, but I think non-power-of-two is supported on SGX hardware (ie, iPhone 3GS onwards, the iPad and all but the 8gb third generation iPod Touch onwards) but not on MBX.</p> <p>The easiest way to deal with non-power-of-two textures here is probably to create a large enough power of two texture and to use glTexSubImage2D to upload just the portion from your source UIView.</p>

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