Added IsInside()

1 files changed, 27 insertions, 3 deletions

diff --git a/vectorgfx.mod/vectorgfx.bmx b/vectorgfx.mod/vectorgfx.bmx
index 57df6ee..fbf5064 100644
--- a/vectorgfx.mod/vectorgfx.bmx
+++ b/vectorgfx.mod/vectorgfx.bmx
@@ -325,10 +325,34 @@ Type TVectorGfxObject
 	End Method
 	
 	Rem
+	bbdoc: Whether a point is inside the object
+	returns: True if the point lies inside the object.  The object is assumed to be a closed polygon for this test.
+	about: @cx, @cy is the point to test.
+	about: Calling it before drawing the object will cause runtime errors.
+	about: This routine is based on code from comp.graphics.algorithms FAQ 2.03
+	EndRem
+	Method IsInside:Int(cx:Int, cy:Int)
+		Local cross:Int=False
+		
+		For Local l:TVectorGfxLine=EachIn lines
+			Local x1:Int=x+rotated[l.i1].x
+			Local y1:Int=y+rotated[l.i1].y
+			Local x2:Int=x+rotated[l.i2].x
+			Local y2:Int=y+rotated[l.i2].y
+			
+			If ((((y1<=cy) And (cy<y2)) Or ((y2<=cy) And (cy<y1))) And (cx < (x2 - x1) * (cy - y1) / (y2 - y1) + x1))
+				cross=Not cross
+			EndIf
+		Next
+		
+		Return cross
+	End Method
+	
+	Rem
 	bbdoc: A line's adjusted co-ordinates.
-	returns: The rotated points (in object co-ordinates) of the line.
+	returns: The rotated and scaled points (in object co-ordinates) of the line.
 	about: @i is the index of the line to return the points for.
-	about: Calling it before drawing then will cause runtime errors.
+	about: Calling it before drawing the object will cause runtime errors.
 	EndRem
 	Method AdjustedCoords:TVectorGfxPoint[](i:Int)
 		Local p:TVectorGfxPoint[]=New TVectorGfxPoint[2]
@@ -342,7 +366,7 @@ Type TVectorGfxObject
 	bbdoc: A line's normal.
 	returns: The normal of the selected line.
 	about: @i is the index of the line to return the normal of.  This will return the normal due to the rotation of the object after the object is drawn.
-	about: Calling it before drawing then will cause runtime errors.
+	about: Calling it before drawing the object will cause runtime errors.
 	EndRem
 	Method Normal:TVector(i:Int)
 		Local l:TVectorGfxLine=lines[i]