Changeset 171 for trunk/Packages/Common/UGeometryClasses.pas

Timestamp:

Nov 23, 2017, 7:05:37 PM (7 years ago)

Author:

chronos

Message:

• Modified: Use specialized TPointF type from generic class.
• Modified: Part of fixes for Voronoi map generation.

File:

• trunk/Packages/Common/UGeometryClasses.pas (modified) (2 diffs)

trunk/Packages/Common/UGeometryClasses.pas

@@ -26 +26 @@
 function PointsToRect(const P1, P2: TPoint): TRect;
 function PointInRect(const P: TPoint; aRect: TRect): Boolean;
+function PtInPoly(const Points: array of TPoint; Pos: TPoint): Boolean;
 function HalfDistancePoint(const P1, P2: TPoint): TPoint;
 function NormalizeAngle(const Angle: Double): Double;
@@ -172 +173 @@
 end;
 
+function PtInPoly(const Points: array of TPoint; Pos: TPoint): Boolean;
+var
+  Count, K, J : Integer;
+begin
+  Result := False;
+  Count := Length(Points) ;
+  J := Count - 1;
+  for K := 0 to Count - 1 do begin
+  if ((Points[K].Y <= Pos.Y) and (Pos.Y < Points[J].Y)) or
+    ((Points[J].Y <= Pos.Y) and (Pos.Y < Points[K].Y)) then
+    begin
+    if (Pos.X < (Points[j].X - Points[K].X) *
+       (Pos.Y - Points[K].Y) /
+       (Points[j].Y - Points[K].Y) + Points[K].X) then
+        Result := not Result;
+    end;
+    J := K;
+  end;
+end;
 
 end.