public AABB(AABB Other)
{
this.X = Other.X;
this.Y = Other.Y;
this.Width = Other.Width;
this.Height = Other.Height;
}
public static bool Inside(ref AABB A, ref Vector2 B)
{
if (B.X < A.X) return false;
if (B.X >= A.X + A.Width) return false;
if (B.Y < A.Y) return false;
if (B.Y >= A.Y + A.Height) return false;
return true;
}
public static bool FuzzySegmentWithAABB(float Fuzz, Vector2 P0, Vector2 P1, AABB AABB)
{
AABB.X += Fuzz;
AABB.Y += Fuzz;
AABB.Width -= 2 * Fuzz;
AABB.Height -= 2 * Fuzz;
return SegmentWithAABB(P0, P1, AABB);
}
public static bool CircleWithAABB(Circle circle, AABB aabb)
{
var circleDistance = new Vector2(
System.Math.Abs(circle.position.X - aabb.Center.X),
System.Math.Abs(circle.position.Y - aabb.Center.Y));
if (circleDistance.X > (aabb.Width / 2 + circle.radius)) return false;
if (circleDistance.Y > (aabb.Height / 2 + circle.radius)) return false;
if (circleDistance.X <= (aabb.Width / 2)) return true;
if (circleDistance.Y <= (aabb.Height / 2)) return true;
var cornerDistance_sq =
(circleDistance.X - aabb.Width / 2) * (circleDistance.X - aabb.Width / 2) +
(circleDistance.Y - aabb.Height / 2) * (circleDistance.Y - aabb.Height / 2);
return (cornerDistance_sq <= (circle.radius * circle.radius));
}
public static bool Intersect(AABB A, AABB B)
{
if (B.X + B.Width < A.X) return false;
if (B.X > A.X + A.Width) return false;
if (B.Y + B.Height < A.Y) return false;
if (B.Y > A.Y + A.Height) return false;
return true;
}
public static bool SegmentWithAABB(Vector2 P0, Vector2 P1, AABB AABB)
{
Vector2[] P = new Vector2[4];
P[0] = new Vector2(AABB.X, AABB.Y);
P[1] = new Vector2(AABB.X + AABB.Width + 1, AABB.Y);
P[2] = new Vector2(AABB.X + AABB.Width + 1, AABB.Y + AABB.Height + 1);
P[3] = new Vector2(AABB.X, AABB.Y + AABB.Height + 1);
Vector2 B = P1;
Vector2 A = P0;
Vector2 Edge = B - A;
Vector2 Normal = new Vector2(-Edge.Y, Edge.X);
float dotMin1, dotMax1, dotMin2, dotMax2;
dotMin1 = dotMax1 = Vector2.Dot(Normal, P0);
float dot = Vector2.Dot(Normal, P1);
if (dot < dotMin1) dotMin1 = dot;
if (dot > dotMax1) dotMax1 = dot;
dotMin2 = dotMax2 = Vector2.Dot(Normal, P[0]);
for (int i = 1; i < 4; ++i)
{
dot = Vector2.Dot(Normal, P[i]);
if (dot < dotMin2) dotMin2 = dot;
if (dot > dotMax2) dotMax2 = dot;
}
if (dotMax1 <= dotMin2 || dotMin1 > dotMax2) return false;
for (int v = 0; v < 4; ++v)
{
B = P[v];
A = P[v == 0 ? 3 : v - 1];
Edge = B - A;
Normal = new Vector2(-Edge.Y, Edge.X);
//float dotMin1, dotMax1, dotMin2, dotMax2;
dotMin1 = dotMax1 = Vector2.Dot(Normal, P0);
dot = Vector2.Dot(Normal, P1);
if (dot < dotMin1) dotMin1 = dot;
if (dot > dotMax1) dotMax1 = dot;
dotMin2 = dotMax2 = Vector2.Dot(Normal, P[0]);
for (int i = 1; i < 4; ++i)
{
dot = Vector2.Dot(Normal, P[i]);
if (dot < dotMin2) dotMin2 = dot;
if (dot > dotMax2) dotMax2 = dot;
}
if (dotMax1 <= dotMin2 || dotMin1 > dotMax2) return false;
}
return true;
}
public static bool PolygonWithAABB(List<Vector2> points, AABB AABB)
{
Vector2[] P = new Vector2[4];
P[0] = new Vector2(AABB.X, AABB.Y);
P[1] = new Vector2(AABB.X + AABB.Width + 1, AABB.Y);
P[2] = new Vector2(AABB.X + AABB.Width + 1, AABB.Y + AABB.Height + 1);
P[3] = new Vector2(AABB.X, AABB.Y + AABB.Height + 1);
for (int v = 0; v < points.Count; ++v)
{
Vector2 B = points[v];
Vector2 A = points[v == 0 ? points.Count - 1 : v - 1];
Vector2 Edge = B - A;
Vector2 Normal = new Vector2(-Edge.Y, Edge.X);
float dotMin1, dotMax1, dotMin2, dotMax2;
dotMin1 = dotMax1 = Vector2.Dot(Normal, points[0]);
for (int i = 1; i < points.Count; ++i)
{
float dot = Vector2.Dot(Normal, points[i]);
if (dot < dotMin1) dotMin1 = dot;
if (dot > dotMax1) dotMax1 = dot;
}
dotMin2 = dotMax2 = Vector2.Dot(Normal, P[0]);
for (int i = 1; i < 4; ++i)
{
float dot = Vector2.Dot(Normal, P[i]);
if (dot < dotMin2) dotMin2 = dot;
if (dot > dotMax2) dotMax2 = dot;
}
if (dotMax1 <= dotMin2 || dotMin1 > dotMax2) return false;
}
for (int v = 0; v < 4; ++v)
{
Vector2 B = P[v];
Vector2 A = P[v == 0 ? 3 : v - 1];
Vector2 Edge = B - A;
Vector2 Normal = new Vector2(-Edge.Y, Edge.X);
float dotMin1, dotMax1, dotMin2, dotMax2;
dotMin1 = dotMax1 = Vector2.Dot(Normal, points[0]);
for (int i = 1; i < points.Count; ++i)
{
float dot = Vector2.Dot(Normal, points[i]);
if (dot < dotMin1) dotMin1 = dot;
if (dot > dotMax1) dotMax1 = dot;
}
dotMin2 = dotMax2 = Vector2.Dot(Normal, P[0]);
for (int i = 1; i < 4; ++i)
{
float dot = Vector2.Dot(Normal, P[i]);
if (dot < dotMin2) dotMin2 = dot;
if (dot > dotMax2) dotMax2 = dot;
}
if (dotMax1 <= dotMin2 || dotMin1 > dotMax2) return false;
}
return true;
}
