private static bool addSupport(Vector3 direction, RayPyramid shape1, EnvironmentObject shape2)
{
Vector3 newVertex = calculateSupport(direction, shape1, shape2);
verticies.Add(newVertex);
return(Vector3.Dot(direction, newVertex) >= 0);
}
private void castRays(List <Ray> rays, List <EnvironmentObject> objects)
{
foreach (EnvironmentObject e in objects)
{
foreach (Ray r in rays)
{
float minDist = float.PositiveInfinity;
EnvironmentObject closestObject = null;
float collisionDist = e.RayCollision(r);
if (collisionDist > 0 && collisionDist < minDist)
{
minDist = collisionDist;
closestObject = e;
}
if (closestObject != null)
{
r.RayColor = closestObject.GetColor();
}
else
{
r.RayColor = Color.Black;
}
}
}
}
public static bool CheckCollision(RayPyramid shape1, EnvironmentObject shape2)
{
verticies = new List <Vector3>();
direction = shape2.GetCenter() - shape1.GetCenter();
int result = 0;
int count = 0;
while (result == 0 && count < 100)
{
result = evolveSimplex(shape1, shape2);
count++;
}
return(result > 0);
}
private static int evolveSimplex(RayPyramid shape1, EnvironmentObject shape2)
{
switch (verticies.Count)
{
case 0:
direction = shape2.GetCenter() - shape1.GetCenter();
break;
case 1:
direction *= -1;
break;
case 2:
//ab is line segment of the two points already gotten
Vector3 ab = verticies[1] - verticies[0];
//a0 is from the first point to the origin
Vector3 a0 = verticies[0] * -1;
Vector3 temp = Vector3.Cross(ab, a0);
//Vector3 temp = Vector3.Cross(a0, ab);
direction = Vector3.Cross(temp, ab);
//direction = Vector3.Cross(ab, temp);
break;
case 3:
Vector3 ac = verticies[2] - verticies[0];
ab = verticies[1] - verticies[0];
direction = Vector3.Cross(ac, ab);
a0 = verticies[0] * -1;
if (Vector3.Dot(direction, a0) < 0)
{
direction *= -1;
}
break;
case 4:
Vector3 da = verticies[3] - verticies[0];
Vector3 db = verticies[3] - verticies[1];
Vector3 dc = verticies[3] - verticies[2];
Vector3 d0 = verticies[3] * -1;
Vector3 abdNorm = Vector3.Cross(da, db);
Vector3 bcdNorm = Vector3.Cross(db, dc);
Vector3 cadNorm = Vector3.Cross(dc, da);
if (Vector3.Dot(abdNorm, d0) > 0)
{
verticies.Remove(verticies[2]);
direction = abdNorm;
}
else if (Vector3.Dot(bcdNorm, d0) > 0)
{
verticies.Remove(verticies[0]);
direction = bcdNorm;
}
else if (Vector3.Dot(cadNorm, d0) > 0)
{
verticies.Remove(verticies[1]);
direction = cadNorm;
}
else
{
return(1);
}
break;
}
return(addSupport(direction, shape1, shape2) ? 0 : -1);
}
private static Vector3 calculateSupport(Vector3 direction, RayPyramid shape1, EnvironmentObject shape2)
{
Vector3 newVertex = shape1.GetSupportingPoint(direction);
newVertex -= shape2.GetSupportPoint(-1 * direction);
return(newVertex);
}
