再学 GDI+[64]: 路径画刷(4) - 还是 SetCenterColor、SetSurroundColors

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 = ($FFFF0000, $FF00FF00, $FF0000FF, $FFFFFF00);
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);

{矩形路径}
path1 := TGPGraphicsPath.Create;
path1.AddRectangle(MakeRect(rt));
pb1 := TGPPathGradientBrush.Create(path1);
num := 4;
pb1.SetSurroundColors(PARGB(@ColorArr), num);
g.FillPath(pb1, path1);

{三角形路径}
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.

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