本例效果圖:
代碼文件: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..2] of TGPColor = (aclRed, aclGreen, aclBlue);
var
pts: array[0..2] of TGPPoint;
g: TGPGraphics;
path: TGPGraphicsPath;
pb: TGPPathGradientBrush;
num: Integer;
begin
pts[0] := MakePoint(80, 10);
pts[1] := MakePoint(10, 150);
pts[2] := MakePoint(150, 150);
g := TGPGraphics.Create(Canvas.Handle);
path := TGPGraphicsPath.Create;
path.AddPolygon(PGPPoint(@pts), Length(pts));
//pb := TGPPathGradientBrush.Create(path); {這樣建立中心默認白色; 按下一句中心默 認黑色}
pb := TGPPathGradientBrush.Create(PGPPoint(@pts), Length(pts)); {根據點數組建立路 徑畫刷}
pb.SetCenterColor(aclWhite);
num := Length(pts);
pb.SetSurroundColors(PARGB(@ColorArr), num);
g.FillPath(pb, path);
{使用灰度校正模式換個地方再畫一次}
pb.SetGammaCorrection(True);
g.TranslateTransform(150, 0);
g.FillPath(pb, path);
pb.Free;
path.Free;
g.Free;
end;
end.
窗體文件:object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClientHeight = 163
ClientWidth = 311
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
