Vertex/image shading (in 2d, based on faked 3d..)

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Plash

Thanks Warpy!

This code works perfect (light vector and colors will be initiated once in the near future):

Local lvec:TVec3, light:Float, dp:Float
lvec = New TVec3.Create(1 / Sqr(3), - 1 / Sqr(3), 1.0)

Local normal1:TVec3, normal2:TVec3, normal:TVec3
normal1 = _quad.topright.Copy()
normal2 = _quad.bottomright.Copy()
normal1.SubtractVec(_quad.topleft)
normal2.SubtractVec(_quad.topleft)

normal = TVec3.CrossProduct(normal1, normal2)
normal.Normalize()
dp = normal.DotProduct(lvec)

If dp < 0 Then dp = 0
light = dp * 0.4 + 0.6
SetColor(light * 255, light * 255, light * 255)

I also changed the quad positions used because they were slightly wrong (topleft = A, topright = B, bottomleft = C, bottomright = D).
I still haven't found the best light position, some seem to make the color change too intense, some not enough.
http://img252.imageshack.us/img252/2800/earlywithshadingmoew5.png
http://img252.imageshack.us/img252/7167/earlywithshadingdebuglizx0.png