Draw an image in Additive Blend Mode without using OpenGL

Question

Hey guys,

I want to draw an image using an additive blend mode. But I don't want to use OpenGL. I can't find anything to do this, maybe there's something in Quartz2D?

Can anyone point me in the right direction?

Cheers, Rich

Answer 1

Hey, Sure there is enum CGBlendMode which you can use to specify blending operation. use method:

CGContextSetBlendMode()

or

[image drawInRect:CGRectMake(0, 0, width, height) blendMode:mode alpha:1];

more at developer site: link text

Cheers, Krzysztof Zabłocki