/// <summary>
/// Checks two shapes for collisions.
/// </summary>
/// <param name="support1">The SupportMappable implementation of the first shape to test.</param>
/// <param name="support2">The SupportMappable implementation of the seconds shape to test.</param>
/// <param name="orientation1">The orientation of the first shape.</param>
/// <param name="orientation2">The orientation of the second shape.</param>
/// <param name="position1">The position of the first shape.</param>
/// <param name="position2">The position of the second shape</param>
/// <param name="point">The pointin world coordinates, where collision occur.</param>
/// <param name="normal">The normal pointing from body2 to body1.</param>
/// <param name="penetration">Estimated penetration depth of the collision.</param>
/// <returns>Returns true if there is a collision, false otherwise.</returns>
public static bool Detect(ISupportMappable support1, ISupportMappable support2, ref FPMatrix orientation1,
ref FPMatrix orientation2, ref FPVector position1, ref FPVector position2,
out FPVector point, out FPVector normal, out FP penetration)
{
// Used variables
FPVector temp1, temp2;
FPVector v01, v02, v0;
FPVector v11, v12, v1;
FPVector v21, v22, v2;
FPVector v31, v32, v3;
FPVector v41 = FPVector.zero, v42 = FPVector.zero, v4 = FPVector.zero;
FPVector mn;
// Initialization of the output
point = normal = FPVector.zero;
penetration = FP.Zero;
//JVector right = JVector.Right;
// Get the center of shape1 in world coordinates -> v01
support1.SupportCenter(out v01);
FPVector.Transform(ref v01, ref orientation1, out v01);
FPVector.Add(ref position1, ref v01, out v01);
// Get the center of shape2 in world coordinates -> v02
support2.SupportCenter(out v02);
FPVector.Transform(ref v02, ref orientation2, out v02);
FPVector.Add(ref position2, ref v02, out v02);
// v0 is the center of the minkowski difference
FPVector.Subtract(ref v02, ref v01, out v0);
// Avoid case where centers overlap -- any direction is fine in this case
if (v0.IsNearlyZero())
{
v0 = new FPVector(FP.EN4, 0, 0);
}
// v1 = support in direction of origin
mn = v0;
FPVector.Negate(ref v0, out normal);
//UnityEngine.Debug.Log("normal: " + normal);
SupportMapTransformed(support1, ref orientation1, ref position1, ref mn, out v11);
SupportMapTransformed(support2, ref orientation2, ref position2, ref normal, out v12);
FPVector.Subtract(ref v12, ref v11, out v1);
if (FPVector.Dot(ref v1, ref normal) <= FP.Zero)
{
return(false);
}
// v2 = support perpendicular to v1,v0
FPVector.Cross(ref v1, ref v0, out normal);
if (normal.IsNearlyZero())
{
FPVector.Subtract(ref v1, ref v0, out normal);
//UnityEngine.Debug.Log("normal: " + normal);
normal.Normalize();
point = v11;
FPVector.Add(ref point, ref v12, out point);
FPVector.Multiply(ref point, FP.Half, out point);
FPVector.Subtract(ref v12, ref v11, out temp1);
penetration = FPVector.Dot(ref temp1, ref normal);
//point = v11;
//point2 = v12;
return(true);
}
FPVector.Negate(ref normal, out mn);
SupportMapTransformed(support1, ref orientation1, ref position1, ref mn, out v21);
SupportMapTransformed(support2, ref orientation2, ref position2, ref normal, out v22);
FPVector.Subtract(ref v22, ref v21, out v2);
if (FPVector.Dot(ref v2, ref normal) <= FP.Zero)
{
return(false);
}
// Determine whether origin is on + or - side of plane (v1,v0,v2)
FPVector.Subtract(ref v1, ref v0, out temp1);
FPVector.Subtract(ref v2, ref v0, out temp2);
FPVector.Cross(ref temp1, ref temp2, out normal);
FP dist = FPVector.Dot(ref normal, ref v0);
// If the origin is on the - side of the plane, reverse the direction of the plane
if (dist > FP.Zero)
{
FPVector.Swap(ref v1, ref v2);
FPVector.Swap(ref v11, ref v21);
FPVector.Swap(ref v12, ref v22);
FPVector.Negate(ref normal, out normal);
UnityEngine.Debug.Log("normal: " + normal);
}
int phase2 = 0;
int phase1 = 0;
bool hit = false;
// Phase One: Identify a portal
while (true)
{
if (phase1 > MaximumIterations)
{
return(false);
}
phase1++;
// Obtain the support point in a direction perpendicular to the existing plane
// Note: This point is guaranteed to lie off the plane
FPVector.Negate(ref normal, out mn);
//UnityEngine.Debug.Log("mn: " + mn);
SupportMapTransformed(support1, ref orientation1, ref position1, ref mn, out v31);
SupportMapTransformed(support2, ref orientation2, ref position2, ref normal, out v32);
FPVector.Subtract(ref v32, ref v31, out v3);
if (FPVector.Dot(ref v3, ref normal) <= FP.Zero)
{
return(false);
}
// If origin is outside (v1,v0,v3), then eliminate v2 and loop
FPVector.Cross(ref v1, ref v3, out temp1);
if (FPVector.Dot(ref temp1, ref v0) < FP.Zero)
{
v2 = v3;
v21 = v31;
v22 = v32;
FPVector.Subtract(ref v1, ref v0, out temp1);
FPVector.Subtract(ref v3, ref v0, out temp2);
FPVector.Cross(ref temp1, ref temp2, out normal);
// UnityEngine.Debug.Log("normal: " + normal);
continue;
}
// If origin is outside (v3,v0,v2), then eliminate v1 and loop
FPVector.Cross(ref v3, ref v2, out temp1);
if (FPVector.Dot(ref temp1, ref v0) < FP.Zero)
{
v1 = v3;
v11 = v31;
v12 = v32;
FPVector.Subtract(ref v3, ref v0, out temp1);
FPVector.Subtract(ref v2, ref v0, out temp2);
FPVector.Cross(ref temp1, ref temp2, out normal);
//UnityEngine.Debug.Log("normal: " + normal);
continue;
}
// Phase Two: Refine the portal
// We are now inside of a wedge...
while (true)
{
phase2++;
/*
* UnityEngine.Debug.LogError(" ::Start STATE");
* UnityEngine.Debug.Log(temp1 + " " + temp2);
* UnityEngine.Debug.Log( v01 + " " + v02 + " "+ v0);
* UnityEngine.Debug.Log( v11+" "+ v12 +" "+ v1);
* UnityEngine.Debug.Log( v21 +" "+ v22 +" "+ v2);
* UnityEngine.Debug.Log( v31 +" "+ v32 +" "+ v3);
* UnityEngine.Debug.Log( v41 +" "+ v42 +" "+ v4);
* UnityEngine.Debug.Log( mn);
*
* UnityEngine.Debug.LogError(" ::END STATE");
*/
// Compute normal of the wedge face
FPVector.Subtract(ref v2, ref v1, out temp1);
FPVector.Subtract(ref v3, ref v1, out temp2);
FPVector.Cross(ref temp1, ref temp2, out normal);
// Beginer
// UnityEngine.Debug.Log("normal: " + normal);
// Can this happen??? Can it be handled more cleanly?
if (normal.IsNearlyZero())
{
return(true);
}
normal.Normalize();
//UnityEngine.Debug.Log("normal: " + normal);
// Compute distance from origin to wedge face
FP d = FPVector.Dot(ref normal, ref v1);
// If the origin is inside the wedge, we have a hit
if (d >= 0 && !hit)
{
// HIT!!!
hit = true;
}
// Find the support point in the direction of the wedge face
FPVector.Negate(ref normal, out mn);
SupportMapTransformed(support1, ref orientation1, ref position1, ref mn, out v41);
SupportMapTransformed(support2, ref orientation2, ref position2, ref normal, out v42);
FPVector.Subtract(ref v42, ref v41, out v4);
FPVector.Subtract(ref v4, ref v3, out temp1);
FP delta = FPVector.Dot(ref temp1, ref normal);
penetration = FPVector.Dot(ref v4, ref normal);
// If the boundary is thin enough or the origin is outside the support plane for the newly discovered vertex, then we can terminate
if (delta <= CollideEpsilon || penetration <= FP.Zero || phase2 > MaximumIterations)
{
if (hit)
{
FPVector.Cross(ref v1, ref v2, out temp1);
FP b0 = FPVector.Dot(ref temp1, ref v3);
FPVector.Cross(ref v3, ref v2, out temp1);
FP b1 = FPVector.Dot(ref temp1, ref v0);
FPVector.Cross(ref v0, ref v1, out temp1);
FP b2 = FPVector.Dot(ref temp1, ref v3);
FPVector.Cross(ref v2, ref v1, out temp1);
FP b3 = FPVector.Dot(ref temp1, ref v0);
FP sum = b0 + b1 + b2 + b3;
if (sum <= 0)
{
b0 = 0;
FPVector.Cross(ref v2, ref v3, out temp1);
b1 = FPVector.Dot(ref temp1, ref normal);
FPVector.Cross(ref v3, ref v1, out temp1);
b2 = FPVector.Dot(ref temp1, ref normal);
FPVector.Cross(ref v1, ref v2, out temp1);
b3 = FPVector.Dot(ref temp1, ref normal);
sum = b1 + b2 + b3;
}
FP inv = FP.One / sum;
FPVector.Multiply(ref v01, b0, out point);
FPVector.Multiply(ref v11, b1, out temp1);
FPVector.Add(ref point, ref temp1, out point);
FPVector.Multiply(ref v21, b2, out temp1);
FPVector.Add(ref point, ref temp1, out point);
FPVector.Multiply(ref v31, b3, out temp1);
FPVector.Add(ref point, ref temp1, out point);
FPVector.Multiply(ref v02, b0, out temp2);
FPVector.Add(ref temp2, ref point, out point);
FPVector.Multiply(ref v12, b1, out temp1);
FPVector.Add(ref point, ref temp1, out point);
FPVector.Multiply(ref v22, b2, out temp1);
FPVector.Add(ref point, ref temp1, out point);
FPVector.Multiply(ref v32, b3, out temp1);
FPVector.Add(ref point, ref temp1, out point);
FPVector.Multiply(ref point, inv * FP.Half, out point);
}
// Compute the barycentric coordinates of the origin
return(hit);
}
//// Compute the tetrahedron dividing face (v4,v0,v1)
//JVector.Cross(ref v4, ref v1, out temp1);
//FP d1 = JVector.Dot(ref temp1, ref v0);
//// Compute the tetrahedron dividing face (v4,v0,v2)
//JVector.Cross(ref v4, ref v2, out temp1);
//FP d2 = JVector.Dot(ref temp1, ref v0);
// Compute the tetrahedron dividing face (v4,v0,v3)
//UnityEngine.Debug.LogError("v4:" + v4 + " v0:" + v0);
FPVector.Cross(ref v4, ref v0, out temp1);
//UnityEngine.Debug.LogError("temp1:"+ temp1);
//Ender
// UnityEngine.Debug.Log("normal: " + normal);
FP dot = FPVector.Dot(ref temp1, ref v1);
if (dot >= FP.Zero)
{
// UnityEngine.Debug.Log("dot >= 0 temp1:" + temp1 + " v2:" + v2 );
dot = FPVector.Dot(ref temp1, ref v2);
if (dot >= FP.Zero)
{
// UnityEngine.Debug.Log("dot >= 0 v1->v4");
// Inside d1 & inside d2 ==> eliminate v1
v1 = v4;
v11 = v41;
v12 = v42;
}
else
{
// UnityEngine.Debug.Log("dot < v3->v4");
// Inside d1 & outside d2 ==> eliminate v3
v3 = v4;
v31 = v41;
v32 = v42;
}
}
else
{
// UnityEngine.Debug.Log("dot < 0 temp1:" + temp1 + " v3:" + v3 );
dot = FPVector.Dot(ref temp1, ref v3);
if (dot >= FP.Zero)
{
// UnityEngine.Debug.Log("dot >= 0 v2 => v4");
// Outside d1 & inside d3 ==> eliminate v2
v2 = v4;
v21 = v41;
v22 = v42;
}
else
{
// UnityEngine.Debug.Log("dot < 0 v1 => v4");
// Outside d1 & outside d3 ==> eliminate v1
v1 = v4;
v11 = v41;
v12 = v42;
}
}
}
}
}