Drawing as subractive?

#1

Hi, is there a way of drawing something with ‘subractive’ rendering. I can do it with OpenGL, but I’d like to use Juce to draw ellipses.

#2

There’s Graphics::excludeClipRegion() for simple areas

You could also use Graphics::reduceClipRegion(const Path&) or Graphics::reduceClipRegion(const Image&) to set up masks

1 Like
#3

Cool. I’ll look into that, thanks!

#4

if you’re drawing paths, try flipping the winding.

2 Likes
#7

OK, I can’t exclude an opaque area Image, just a rectangle and I can’t draw zero alpha ellipses, so I’m just going to draw the whole off-screen bitmap in a very faint black and white, it seems OK to be honest, and it gives a good hint as to what’s happening. Thanks!!! :slight_smile: