void FillTriangle(Vertex v1, Vertex v2, Vertex v3, Bitmap texture)
{
var screenSpace = Matrix4Utils.ScreenSpace(Width / 2, Height / 2);
Matrix4 iden = Matrix4.Identity;
Vertex minYVert = v1.Transform(screenSpace, iden).PerspectiveDivide();
Vertex midYVert = v2.Transform(screenSpace, iden).PerspectiveDivide();
Vertex maxYVert = v3.Transform(screenSpace, iden).PerspectiveDivide();
if (minYVert.TriangleAreaTimesTwo(maxYVert, midYVert) >= 0)
{
return;
}
if (maxYVert.Y < midYVert.Y)
{
Swap(ref maxYVert, ref midYVert);
}
if (midYVert.Y < minYVert.Y)
{
Swap(ref midYVert, ref minYVert);
}
if (maxYVert.Y < midYVert.Y)
{
Swap(ref maxYVert, ref midYVert);
}
float a = minYVert.TriangleAreaTimesTwo(maxYVert, midYVert);
ScanTriangle(minYVert, midYVert, maxYVert, a >= 0, texture);
}
