public static Vector2 GetResolution(PolygonSchema a, PolygonSchema b)
{
RectangleF aAABB = CalculateAABB(a.Vertices);
RectangleF bAABB = CalculateAABB(b.Vertices);
if (!aAABB.Intersects(bAABB))
{
return(new Vector2(0, 0));
}
OverlapInformation pass0 = CalculateOverlap(a, b);
OverlapInformation pass1 = CalculateOverlap(b, a);
if (!pass0.Valid || !pass1.Valid)
{
return(new Vector2(0, 0));
}
OverlapInformation minPass = pass0.Overlap < pass1.Overlap ? pass0 : pass1;
Vector2 resolution = minPass.Normal * minPass.Overlap;
Vector2 temp = aAABB.Center - bAABB.Center;
resolution = Vector2.Dot(temp, resolution) < 0 ? -resolution : resolution;
return(resolution);
}
private static OverlapInformation CalculateOverlap(PolygonSchema a, PolygonSchema b)
{
Vector2 minNormal = Vector2.Zero;
float minOverlap = float.MaxValue;
for (int i = 0; i < a.Edges.Length; i++)
{
Vector2 normal = new Vector2(
-(a.Edges[i].Y2 - a.Edges[i].Y1),
a.Edges[i].X2 - a.Edges[i].X1
);
normal.Normalize();
float minProjectionA = float.MaxValue;
float maxProjectionA = float.MinValue;
for (int j = 0; j < a.Vertices.Length; j++)
{
float projection = Vector2.Dot(a.Vertices[j], normal);
minProjectionA = Math.Min(minProjectionA, projection);
maxProjectionA = Math.Max(maxProjectionA, projection);
}
float minProjectionB = float.MaxValue;
float maxProjectionB = float.MinValue;
for (int j = 0; j < b.Vertices.Length; j++)
{
float projection = Vector2.Dot(b.Vertices[j], normal);
minProjectionB = Math.Min(minProjectionB, projection);
maxProjectionB = Math.Max(maxProjectionB, projection);
}
float overlap = Math.Min(maxProjectionA, maxProjectionB) - Math.Max(minProjectionA, minProjectionB);
if (overlap < minOverlap)
{
minOverlap = overlap;
minNormal = normal;
}
if (maxProjectionB < minProjectionA || maxProjectionA < minProjectionB)
{
return(new OverlapInformation());
}
}
return(new OverlapInformation(minNormal, minOverlap));
}
public static bool Intersects(PolygonSchema a, PolygonSchema b)
{
RectangleF aAABB = CalculateAABB(a.Vertices);
RectangleF bAABB = CalculateAABB(b.Vertices);
if (!aAABB.Intersects(bAABB))
{
return(false);
}
OverlapInformation pass0 = CalculateOverlap(a, b);
OverlapInformation pass1 = CalculateOverlap(b, a);
if (!pass0.Valid || !pass1.Valid)
{
return(false);
}
return(true);
}