true algorithm for edge detection
Yes, I wouldn't be doing a full-edge detection because that would be silly . . it normally takes at least couple of seconds to apply such a filter to a desktop sized image, because it's a raster effect and has to be applied to ALL pixels on screen. I'm dealing with vectors and line drawing, not raster filters here. . .
I don't think that I'll be doing much more calculation when I add the part that checks for edges with a front facing + back facing triangle next to it, at least not enough more for it to have a major perfomance hit.
I do however think that any attempt to 'cull' the line drawing based on whether a line is behind an object or not might be heavy on the calculations.
Hmmm. Here's a thought - perhaps I could combine a raster-edge detection with the line drawing method: Use the line technique to decide where on screen to apply the edge detection. That way the edge-detection is only applied to a small portion of the screen... it would solve the lines behind an object problem completely!
I bet it would be really slow, but I think its probably going to be a fun experiment. . . :O)