collision.cg

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void main(float2 par_tri_coord : TEXCOORD0,
		  //float2 tri_coord : TEXCOORD1,
		  uniform samplerRECT attr_rect : TEXUNIT0,
		  uniform samplerRECT tri_rect  : TEXUNIT1,
		  out float3 result : COLOR)
{
	float k = 30000.0;
	float radius = 0.004;

	float3 pos = f3texRECT(attr_rect, float2(par_tri_coord.x, 0));
	float3 vel = f3texRECT(attr_rect, float2(par_tri_coord.x, 1));//par_coord + float2(0, 1));

	float2 basei = float2(8*floor(par_tri_coord.y), 0);
	
	/* triangle 0 */
	float3 a0 = f3texRECT(tri_rect, basei);
	float3 a1 = f3texRECT(tri_rect, basei + float2(1.0, 0.0));
	float3 a2 = f3texRECT(tri_rect, basei + float2(2.0, 0.0));
	float3 v0 = f3texRECT(tri_rect, basei + float2(3.0, 0.0));
	//float3 n0 = f3texRECT(tri_rect, basei + float2(4.0, 0.0));

	/* triangle 1 */
	float3 a3 = f3texRECT(tri_rect, basei + float2(4.0, 0.0));
	float3 a4 = f3texRECT(tri_rect, basei + float2(5.0, 0.0));
	float3 a5 = f3texRECT(tri_rect, basei + float2(6.0, 0.0));
	float3 v1 = f3texRECT(tri_rect, basei + float2(7.0, 0.0));
	//float3 n1 = f3texRECT(tri_rect, basei + float2(7.0, 0.0));
	
	const float EPSILON = 0.000001f;

	float dist0;
	float3 p0_tri = pos - v0;
	p0_tri = float3(dot(a0, p0_tri), dot(a1, p0_tri), dot(a2, p0_tri));
	/*
	if ((0.0f > p0_tri.x) || (0.0f > p0_tri.y) || ((p0_tri.x + p0_tri.y) > 1.0f))
	{
		p0_tri.z = 4*radius;
	}
	*/

	float3 p1_tri = pos - v1;
	p1_tri = float3(dot(a3, p1_tri), dot(a4, p1_tri), dot(a5, p1_tri));
	/*
	if ((0.0f > p1_tri.x) || (0.0f > p1_tri.y) || ((p1_tri.x + p1_tri.y) > 1.0f))
	{
		p1_tri.z = 4*radius;
	}
	*/
/*
		return p_tri.z;
	
	return p_tri.z + p_tri.x*p_tri.x + p_tri.y*p_tri.y;
*/
	float diff;

	float3 n;
	if (p0_tri.z < p1_tri.z)
	{
		n = a2;
		//dist = dist0;
		diff = 2.0*radius - p0_tri.z;
	}
	else
	{
		n = a5;
		//dist = dist1;
		diff = 2.0*radius - p1_tri.z;
	}

	if (diff > EPSILON)
	{
		float vel0 = dot(vel, n);
		result = (k*diff - 64.0*vel0)*n;
	}
	else result = float3(0.0, 0.0, 0.0);

	/*

	float diff0 = 2.0*radius - dist0;
	float diff1 = 2.0*radius - dist1;

//	float diff = 2.0*radius - min(dist0, dist1);

	if (diff0 > EPSILON)
	{
		float vel0 = dot(vel, n0);
		result.xyz = (k*diff0 - 64.0f*vel0)*n0;
//		result.xyz = k*diff*normal;//(k*diff - 64.0f*vel0)*normal;
	}
	else result.xyz = float3(0.0, 0.0, 0.0);

	if (diff0 > EPSILON)
	{
		float vel0 = dot(vel, n0);
		result.xyz = (k*diff0 - 64.0f*vel0)*n0;
//		result.xyz = k*diff*normal;//(k*diff - 64.0f*vel0)*normal;
	}
	else result.xyz = float3(0.0, 0.0, 0.0);*/
}