代码文件:
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); {这样建立中心默认白色; 按下一句中心默认黑色} pb := TGPPathGradientBrush.Create(PGPPoint(@pts), Length(pts)); {根据点数组建立路径画刷} pb.SetCenterColor(aclWhite); num := Length(pts); pb.SetSurroundColors(PARGB(@ColorArr), num); g.FillPath(pb, path); {使用灰度校正模式换个地方再画一次} pb.SetGammaCorrection(True); g.TranslateTransform(150, 0); g.FillPath(pb, path); pb.Free; path.Free; g.Free; end; end.窗体文件:
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