!!ARBvp1.0
#
# Program environment parameters:
# c[0].xyz = normalized light direction in object-space
#
# outputs diffuse illumination for color and perturbed position
#
	ATTRIB iPos         = vertex.position;
	ATTRIB iNormal      = vertex.normal;
	PARAM  mvp[4]       = { state.matrix.mvp };
	PARAM  lightDir     = program.env[0];
	PARAM  diffuseCol   = { 1, 1, 0, 1 };
	TEMP   temp;
	OUTPUT oPos         = result.position;
	OUTPUT oColor       = result.color;

	DP3   temp, lightDir, iNormal;
	MUL   oColor.xyz, temp, diffuseCol;
	MAX   temp, temp, 0;            # clamp dot product to zero
	MUL   temp, temp, iNormal;      # align in direction of normal
	MUL   temp, temp, 0.125;        # scale displacement by 1/8
	SUB   temp, temp, iPos;         # perturb
	DP4   oPos.x, mvp[0], temp;     # xform using perturbed position
	DP4   oPos.y, mvp[1], temp;
	DP4   oPos.z, mvp[2], temp;
	DP4   oPos.w, mvp[3], temp;
	END