I usually use the cross product of the directions to two other points close to the current vertex. In your case one could of course simplify that a bit. No idea if it fits into the shadermodel though...

If I didn´t confuse a1-3 and b1-3 something like this should do the job:
Code:
float height = sin((vecTime.w + inPosition.x) * 0.1) * 8;
float heightnext = sin((vecTime.w + inPosition.x+VERTDISTINX) * 0.1) * 8;
inPosition.y += height;
inNormal = normalize(float3((heightnext-height)*VERTDISTINX, -VERTDISTINX*VERTDISTINX, 0.0));


Last edited by Slin; 01/29/11 21:43.
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