2D Triangle rasterization algorithm

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Hello,

I’m writing research paper on software rasterization algorithms and at one point I gave example of triangle rasterization algorithm.

The algorithm is really basic. If the triangle is flat top or flat bottom it’s possible to determine the minimum and the maximum x values for each scan line using the equation of line for the edges. Then for each scan line fill the pixels between minimum x and maximum x values.
If the triangle is of other kind it’s possible to split it to flat top and flat bottom triangles (finding the fourth vertex) and draw it using the previous algorithm.

I need to cite a reference for this algorithm. I saw it in some book in the ‘90s and I can’t just write it without a reference. The problem is that I can’t remember where I saw it.
I already tried to look at “Computer Graphics: Principles and Practice” but the only similar algorithm there is the polygon rasterization algorithm, which is over engineered for this kind of problem, same with "Computer Graphics: C Version".
I also tried to look at “Black Art of 3D Game Programming”, which have similar algorithm but the algorithm that I saw was in another book and slightly different.

Anyone know a book with this kind of algorithm?
Any help is appreciated.

Thanks.

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Michael Abrash's Graphics Programming Black Book might be another reference, but polygons too IIRC.

Note that rendering polygons is much more efficient than triangles due to less edges to setup - if there is enough planar stuff around.

Later there was a SIMD approach which does a bounding rect per triangle and then evaluating 3 side of edge tests in parallel per pixel. I remember a guy named Nicolas Capens who wrote an article about this, might be another good reference.

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IIRC "Tricks of the 3D Game Programming Gurus-Advanced 3D Graphics and Rasterization" by Andre laMothe has that algorithm.

For a different method of rasterization look here: http://forum.devmaster.net/t/advanced-rasterization/6145

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