draw to a UIImage with CoreGraphics

CGFloat width, height;		// max 1024 due to Core Graphics limitations
UIImage *inputImage;		// input image to be composited over new image as example
 
// create a new bitmap image context
//
UIGraphicsBeginImageContext(CGSizeMake(width, height));		
 
// get context
//
CGContextRef context = UIGraphicsGetCurrentContext();		
 
// push context to make it current 
// (need to do this manually because we are not drawing in a UIView)
//
UIGraphicsPushContext(context);								
 
// 
// [drawing code comes here- look at CGContext reference
// for available operations]
//
 
// this example draws the inputImage into the context
//
[inputImage drawInRect:CGRectMake(0, 0, width, height)];
 
 
// pop context 
//
UIGraphicsPopContext();								
 
// get a UIImage from the image context- enjoy!!!
//
UIImage *outputImage = UIGraphicsGetImageFromCurrentImageContext();
 
// clean up drawing environment
//
UIGraphicsEndImageContext();