/// <summary>
/// iterates all the edges of the polygon and gets the closest point on any edge to point. Returns via out the squared distance
/// to the closest point and the normal of the edge it is on.
/// </summary>
/// <returns>The closest point on polygon to point.</returns>
/// <param name="point">Point.</param>
/// <param name="distanceSquared">Distance squared.</param>
/// <param name="edgeNormal">Edge normal.</param>
public Vector2 getClosestPointOnPolygonToPoint(Vector2 point, out float distanceSquared, out Vector2 edgeNormal)
{
distanceSquared = float.MaxValue;
edgeNormal = Vector2.Zero;
var closestPoint = Vector2.Zero;
float tempDistanceSquared;
for (var i = 0; i < points.Length; i++)
{
var j = i + 1;
if (j == points.Length)
{
j = 0;
}
var closest = ShapeCollisions.closestPointOnLine(points[i], points[j], point);
Vector2.DistanceSquared(ref point, ref closest, out tempDistanceSquared);
if (tempDistanceSquared < distanceSquared)
{
distanceSquared = tempDistanceSquared;
closestPoint = closest;
// get the normal of the line
var line = points[j] - points[i];
edgeNormal.X = line.Y;
edgeNormal.Y = -line.X;
}
}
return(closestPoint);
}
public override bool pointCollidesWithShape(Vector2 point, out CollisionResult result)
{
if (isUnrotated)
{
return(ShapeCollisions.pointToBox(point, this, out result));
}
return(base.pointCollidesWithShape(point, out result));
}
public override bool PointCollidesWithShape(System.Numerics.Vector2 point, out CollisionResult result)
{
if (IsUnrotated)
{
return(ShapeCollisions.PointToBox(point, this, out result));
}
return(base.PointCollidesWithShape(point, out result));
}
public override bool CollidesWithShape(Shape other, out CollisionResult result)
{
// special, high-performance cases. otherwise we fall back to Polygon.
if (IsUnrotated && other is Box && (other as Box).IsUnrotated)
{
return(ShapeCollisions.BoxToBox(this, other as Box, out result));
}
// TODO: get Minkowski working for circle to box
//if( other is Circle )
// fallthrough to standard cases
return(base.CollidesWithShape(other, out result));
}
public override bool collidesWithShape(Shape other, out CollisionResult result)
{
if (other is Polygon)
{
return(ShapeCollisions.polygonToPolygon(this, other as Polygon, out result));
}
if (other is Circle && ShapeCollisions.circleToPolygon(other as Circle, this, out result))
{
result.invertResult();
return(true);
}
throw new NotImplementedException(string.Format("overlaps of Polygon to {0} are not supported", other));
}
public override bool overlaps(Shape other)
{
CollisionResult result;
if (other is Polygon)
{
return(ShapeCollisions.polygonToPolygon(this, other as Polygon, out result));
}
if (other is Circle)
{
ShapeCollisions.circleToPolygon(other as Circle, this, out result);
}
throw new NotImplementedException(string.Format("overlaps of Polygon to {0} are not supported", other));
}
public override bool collidesWithShape(Shape other, out CollisionResult result)
{
if (other is Polygon)
{
return(ShapeCollisions.polygonToPolygon(this, other as Polygon, out result));
}
if (other is Circle && ShapeCollisions.circleToPolygon(other as Circle, this, out result))
{
// TODO: flip the result since the colliding objects are reversed
throw new NotImplementedException("ShapeCollisionResult will probably be wrong due to the result needing to be flipped. TODO");
//return true;
}
throw new NotImplementedException(string.Format("overlaps of Polygon to {0} are not supported", other));
}
public override bool collidesWithShape(Shape other, out CollisionResult result)
{
if (other is Box && (other as Box).isUnrotated)
{
return(ShapeCollisions.circleToBox(this, other as Box, out result));
}
if (other is Circle)
{
return(ShapeCollisions.circleToCircle(this, other as Circle, out result));
}
if (other is Polygon)
{
return(ShapeCollisions.circleToPolygon(this, other as Polygon, out result));
}
throw new NotImplementedException(string.Format("Collisions of Circle to {0} are not supported", other));
}
public override bool overlaps(Shape other)
{
CollisionResult result;
if (other is Box)
{
return(Collisions.rectToCircle(ref other.bounds, position, radius));
}
if (other is Circle)
{
return(Collisions.circleToCircle(position, radius, other.position, (other as Circle).radius));
}
if (other is Polygon)
{
return(ShapeCollisions.circleToPolygon(this, other as Polygon, out result));
}
throw new NotImplementedException(string.Format("overlaps of Circle to {0} are not supported", other));
}
public override bool Overlaps(Shape other)
{
CollisionResult result;
// Box is only optimized for unrotated
if (other is Box && (other as Box).IsUnrotated)
{
return(Collisions.RectToCircle(ref other.bounds, position, Radius));
}
if (other is Circle)
{
return(Collisions.CircleToCircle(position, Radius, other.position, (other as Circle).Radius));
}
if (other is Polygon)
{
return(ShapeCollisions.CircleToPolygon(this, other as Polygon, out result));
}
throw new NotImplementedException(string.Format("overlaps of Circle to {0} are not supported", other));
}
public override bool pointCollidesWithShape(Vector2 point, out CollisionResult result)
{
return(ShapeCollisions.pointToCircle(point, this, out result));
}
public override bool collidesWithLine(Vector2 start, Vector2 end, out RaycastHit hit)
{
hit = new RaycastHit();
return(ShapeCollisions.lineToCircle(start, end, this, out hit));
}
public override bool PointCollidesWithShape(Vector2 point, out CollisionResult result)
{
return(ShapeCollisions.PointToPoly(point, this, out result));
}
public override bool PointCollidesWithShape(System.Numerics.Vector2 point, out CollisionResult result)
{
return(ShapeCollisions.PointToCircle(point, this, out result));
}
public override bool CollidesWithLine(System.Numerics.Vector2 start, System.Numerics.Vector2 end, out RaycastHit hit)
{
hit = new RaycastHit();
return(ShapeCollisions.LineToCircle(start, end, this, out hit));
}