Re-learning gdi+[64]: Path brushes (4)

In this case, the Centercolor is not specified, and white is the default;

Surroundcolors is the point in the corresponding path (but does not work in the ellipse in the following way).

This example effect chart:

Code files:Unit Unit1;
Interface
Uses
Windows, Messages, sysutils, variants, Classes, Graphics, Controls, Forms,
Dialogs;
Type
TForm1 = Class (Tform)
Procedure Formpaint (Sender:tobject);
End
Var
Form1:tform1;
Implementation
{$R *.DFM}
Uses Gdipobj, GDIPAPI;
Procedure Tform1.formpaint (Sender:tobject);
Const
COLORARR:ARRAY[0..3] of Tgpcolor = ($FFFF 0000, $FF 00ff00, $FF 0000FF, $FFFFFF 00);
Var
Rt:trect;
Pts:array of Tgppoint;
G:tgpgraphics;
Path1, Path2:tgpgraphicspath;
Pb1,pb2:tgppathgradientbrush;
Num:integer;
Begin
RT: = Bounds (10, 10, 150, 150);
G: = Tgpgraphics.create (Canvas.handle);
{Rectangular Path}
path1: = tgpgraphicspath.create;
Path1. AddRectangle (Makerect (RT));
PB1: = Tgppathgradientbrush.create (path1);
num: = 4;
PB1. Setsurroundcolors (Pargb (@ColorArr), num);
G.fillpath (PB1, path1);
{Triangle Path}
Offsetrect (RT, 160, 0);
SetLength (pts, 3);
Pts[0]: = Makepoint (Rt. Left + (Rt. Right-rt.left) Div 2, Rt. top);
PTS[1]: = Makepoint (Rt. Left, Rt. Bottom);
PTS[2]: = Tgppoint (Rt. BottomRight);
path2: = tgpgraphicspath.create;
Path2. Addpolygon (Pgppoint (pts), Length (pts));
PB2: = Tgppathgradientbrush.create (path2);
num: = 3;
Pb2. Setsurroundcolors (Pargb (@ColorArr), num);
G.fillpath (PB2, path2);
PB1. Free;
Pb2. Free;
Path1. Free;
Path2. Free;
G.free;
End
End.

Form file:object Form1: TForm1
　Left = 0
　Top = 0
　Caption = 'Form1'
　ClientHeight = 172
　ClientWidth = 327
　Color = clBtnFace
　Font.Charset = DEFAULT_CHARSET
　Font.Color = clWindowText
　Font.Height = -11
　Font.Name = 'Tahoma'
　Font.Style = []
　OldCreateOrder = False
　Position = poDesktopCenter
　OnPaint = FormPaint
　PixelsPerInch = 96
　TextHeight = 13
end