Function RayTriangleIntersection

trinity/Resources/TriGrannyRes.cpp:1825–1865

bool RayTriangleIntersection( float& dist, float& u, float& v, const Vector3& pos, const Vector3& dir, const Vector3& p0, const Vector3& p1, const Vector3& p2 )
{
	Matrix m;
	Vector4 vec;

	m.m[0][0] = p1.x - p0.x;
	m.m[1][0] = p2.x - p0.x;
	m.m[2][0] = -dir.x;
	m.m[3][0] = 0.0f;
	m.m[0][1] = p1.y - p0.y;
	m.m[1][1] = p2.y - p0.y;
	m.m[2][1] = -dir.y;
	m.m[3][1] = 0.0f;
	m.m[0][2] = p1.z - p0.z;
	m.m[1][2] = p2.z - p0.z;
	m.m[2][2] = -dir.z;
	m.m[3][2] = 0.0f;
	m.m[0][3] = 0.0f;
	m.m[1][3] = 0.0f;
	m.m[2][3] = 0.0f;
	m.m[3][3] = 1.0f;

	vec.x = pos.x - p0.x;
	vec.y = pos.y - p0.y;
	vec.z = pos.z - p0.z;
	vec.w = 0.0f;

	if( Inverse( m, m ) )
	{
		vec = Transform( vec, m );
		if( ( vec.x >= 0.0f ) && ( vec.y >= 0.0f ) && ( vec.x + vec.y <= 1.0f ) && ( vec.z >= 0.0f ) )
		{
			u = vec.x;
			v = vec.y;
			dist = fabs( vec.z );
			return true;
		}
	}

	return false;
}

#if WITH_GRANNY
namespace