Polygon Sweep-Line Algorithm
void ScanPolygon(Triangle T, Color rgba){
sort edges by maxy
make empty “active edge list”
for each scanline (top-to-bottom) { insert/remove edges from “active edge list”
update x coordinate of every active edge
sort active edges by x coordinate
for each pair of active edges (left-to-right)
SetPixels(xi, xi+1, y, rgba);
}
}