protected static bool handlePCMovement(Collider mover, Collider other, Vector2 dp, out Vector2 allowedMovement)
{
switch (other.type)
{
case ColliderType.Scenery:
allowedMovement = scaleBackVelocity(mover, other, dp);
return true;
//case ColliderType.PC:
// return handlePCMovement(mover, other, dp, out allowedMovement);
// break;
case ColliderType.NPC:
allowedMovement = scaleBackVelocity(mover, other, dp);
return true;
// break;
//case ColliderType.Effect:
// break;
//case ColliderType.Movable:
// break;
//case ColliderType.Trigger:
// allowedMovement = Vector2.Zero;
// ((Trigger)other.owner).handleImpact(mover);
// return false;
default:
throw new Exception("PC moved into something it shouldn't have");
}
}
protected static Vector2 scaleBackVelocity(Collider mover, Collider other, Vector2 dp)
{
// whew! a lot work just to make it so that you can slide along objects when
// using multiple directions
const float EPS = 0.01f;
DoubleRect dr2 = other.Bounds;
double reducedX = dp.X;
double reducedY = dp.Y;
// Project x only movement and fix x velocity
Vector2 temp = new Vector2(dp.X, 0);
DoubleRect dr1 = mover.Bounds + temp;
if (dr1.IntersectsWith(dr2))
if (dp.X > 0 && dr1.X + dr1.Width >= dr2.X) // moving right, rhs collision
{
double overlap = dr1.X + dr1.Width - dr2.X + EPS;
reducedX = Math.Max(0.0f, dp.X - overlap);
}
else if (dp.X < 0 && dr1.X <= dr2.X + dr2.Width) // moving left, lhs collision
{
double overlap = (dr2.X + dr2.Width) - dr1.X + EPS;
reducedX = Math.Min(0.0f, dp.X + overlap);
}
// Project y only movement and fix y velocity
temp = new Vector2(0, dp.Y);
dr1 = mover.Bounds + temp;
if (dr1.IntersectsWith(dr2))
if (dp.Y > 0 && dr1.Y + dr1.Height >= dr2.Y) // moving down, bottom collision
{
double overlap = dr1.Y + dr1.Height - dr2.Y + EPS;
reducedY = Math.Max(0.0f, dp.Y - overlap);
}
else if (dp.Y < 0 && dr1.Y <= dr2.Y + dr2.Height) // moving up, top collision
{
double overlap = (dr2.Y + dr2.Height) - dr1.Y + EPS;
reducedY = Math.Min(0.0f, dp.Y + overlap);
}
// TODO make this more intelligent? not sure how
// if neither X nor Y reduced, must be a corner collision
// for now, we just won't allow this (if we allow, you can get stuck, but not bad)
if (reducedX == dp.X && reducedY == dp.Y)
{
return Vector2.Zero;
}
return new Vector2((float)reducedX, (float)reducedY);
}
public static bool handleMovement(Collider mover, Collider other, Vector2 dp, out Vector2 allowedMovement)
{
switch (mover.type)
{
case ColliderType.PC:
return handlePCMovement(mover, other, dp, out allowedMovement);
//case ColliderType.NPC:
// break;
//case ColliderType.Effect:
// break;
//case ColliderType.Movable:
// break;
default:
throw new Exception("Something's moving that shouldn't be");
}
return false;
}
