private bool OnContact(RigidBody body1, RigidBody body2, JVector point1, JVector point2, JVector normal,
JVector[] triangle, float penetration)
{
// By design, all physics objects have entities attached, with the exception of static parts of the map. In
// the case of map collisions, it's unknown which body comes first as an argument (as of writing this
// comment, anyway), which is why both entities are checked for null.
Entity entity1 = body1.Tag as Entity;
Entity entity2 = body2.Tag as Entity;
vec3 p1 = point1.ToVec3();
vec3 p2 = point2.ToVec3();
// The normal needs to be flipped based on how Jitter handles triangle winding.
//vec3 n = Utilities.Normalize(-normal.ToVec3());
vec3 n = Utilities.Normalize(normal.ToVec3());
// A triangle will only be given in the case of collisions with a triangle mesh (or terrain).
if (triangle != null)
{
var entity = entity1 ?? entity2;
var point = entity1 != null ? p2 : p1;
var tArray = triangle.Select(t => t.ToVec3()).ToArray();
return(entity.OnContact(point, n, tArray));
}
bool b1 = entity1?.OnContact(entity2, body2, p1, -n) ?? true;
bool b2 = entity2?.OnContact(entity1, body1, p2, n) ?? true;
// Either entity can negate the contact.
return(b1 && b2);
}
private static bool RaycastInternal(World world, RigidBody body, vec3 start, vec3 ray,
out RaycastResults results)
{
JVector jStart = start.ToJVector();
// Note that Jitter's Raycast signature below calls one of its parameters "rayDirection", but that vector
// isn't meant to be normalized (meaning that it's actually just a ray from start to end).
JVector jDirection = ray.ToJVector();
JVector normal;
JVector[] triangle;
var system = world.CollisionSystem;
float fraction;
bool success = body != null
? system.Raycast(body, jStart, jDirection, out normal, out fraction, out triangle)
: system.Raycast(jStart, jDirection, (b, n, f) => true, out body, out normal,
out fraction, out triangle);
if (!success || fraction > 1)
{
results = null;
return(false);
}
vec3[] tVectors = null;
// Triangle will only be set if a triangle mesh was hit.
if (triangle != null)
{
tVectors = new vec3[3];
for (int i = 0; i < 3; i++)
{
tVectors[i] = triangle[i].ToVec3();
}
}
results = new RaycastResults(body, start + jDirection.ToVec3() * fraction,
Utilities.Normalize(normal.ToVec3()), tVectors);
return(true);
}