GpFillmode enumeration

Selects the rule that decides which areas of a self-intersecting path are filled.

The rule matters only where a path crosses itself or holds shapes inside one another. A GraphicsPath keeps its rule in the FillMode property, and the polygon and curve fills of Graphics take it as an argument.

Member Value Description
FillModeAlternate 0 The even-odd rule. A point is filled when a line from it to infinity crosses the path an odd number of times, so the fill alternates between filled and empty areas at each boundary. A shape inside another leaves a hole.
FillModeWinding 1 The nonzero winding rule. A point is filled when the path winds around it a net non-zero number of times. A shape drawn inside another in the same direction is filled; one drawn in the opposite direction leaves a hole.

Used by

Example 

Dim user As GdiPlusUser = GdiPlusUser()
Dim bmp As Bitmap = Bitmap(30!, 30!)
Dim g As Graphics = Graphics(bmp)

' Two rectangles, one inside the other, both drawn in the same direction.
Dim path As GraphicsPath = GraphicsPath(FillModeAlternate)
path.AddRectangle(2, 2, 26, 26)
path.AddRectangle(8, 8, 14, 14)

g.Clear(White)
g.FillPath(SolidBrush(CColor.Black), path)
Debug.Print Hex$(bmp.Pixel(4, 4).Value), Hex$(bmp.Pixel(15, 15).Value)

path.FillMode = FillModeWinding
g.Clear(White)
g.FillPath(SolidBrush(CColor.Black), path)
Debug.Print Hex$(bmp.Pixel(4, 4).Value), Hex$(bmp.Pixel(15, 15).Value)
' Output:
' FF000000      FFFFFFFF
' FF000000      FF000000

The pixel in the ring is black in both runs. The pixel inside the inner rectangle is white with FillModeAlternate (a hole) and black with FillModeWinding.

See Also