collision_glass.cg

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//void main(float2 par_tri_coord : TEXCOORD0,
void main(float pindex : TEXCOORD0,
		  uniform samplerRECT attr_rect : TEXUNIT0,
		  //uniform samplerRECT tri_rect  : TEXUNIT1,
		  uniform float4x4 mat_col,
		  uniform float4x4 mat_inv_col,
		  out float3 result : COLOR)
{
//
	float k = 25000.0;
//	float k = 20000.0;
	float radius = 0.004;
	const float GLASS_R = 0.05;
	const float GLASS_BOTTOM = -0.0;
	const float GLASS_TOP = 0.19;
	//const float GLASS_BOTTOM = -0.05;
	//const float GLASS_TOP = 0.14;
	const float EPSILON = 0.000001f;

	/*
	float4 pp;
	pp.xyz = f3texRECT(attr_rect, float2(pindex, 0));
	pp.w = 1.0;
	float3 vel = f3texRECT(attr_rect, float2(pindex, 1));
*/
	float4 pp = float4(f3texRECT(attr_rect, float2(pindex, 0)), 1);
	float3 vel = mul((float3x3)mat_col, f3texRECT(attr_rect, float2(pindex, 1)));

	float3 pos = mul(mat_col, pp).xyz;

	float dist = GLASS_R - sqrt(dot(pos.xy, pos.xy));
//	float dist = GLASS_R - distance(pos.xy);//sqrt(dot(pos.xy, pos.xy))
	float diff = 2.0*radius - dist;

	float3 col_force = float3(0, 0, 0);
	if (diff > EPSILON)
	{
		float3 n = -normalize(float3(pos.x, pos.y, 0.0));
		float vel0 = dot(vel, n);
		col_force += max(k*diff - 64.0*vel0, 0.0)*n;
	}
	//else result = float3(0.0, 0.0, 0.0);
/*
	if (diff > EPSILON)
	{
		float3 n = -normalize(float3(pos.x, pos.y, 0.0));
		float vel0 = dot(vel, n);
		result = (k*diff - 64.0*vel0)*n;
	}
	else result = float3(0.0, 0.0, 0.0);*/

	diff = 2.0f*radius - (pos.z - GLASS_BOTTOM);
//	diff = 2.0f*radius - pos.z;// - GLASS_BOTTOM);

	if (diff > EPSILON)
	{
		float3 n = float3(0, 0, 1);
		float vel0 = dot(vel, n);//vec3_dot(&n, &sph->vel[i]);

		col_force += max(k*diff - 64.0*vel0, 0.0)*n;
	}

	
	diff = 2.0f*radius - (GLASS_TOP - pos.z);
	if (diff > EPSILON)
	{
		float3 n = float3(0, 0, -1);
		float vel0 = dot(vel, n);
		col_force += max(k*diff - 64.0*vel0, 0.0)*n;
	}

	result = mul((float3x3)mat_inv_col, col_force);
//	result = col_force;//mul((float3x3)mat_inv_col, col_force);

}