GDI+绘制简单的线条与绘图质量常数

 1 unit Unit1;
 2 
 3 interface
 4 
 5 uses
 6   Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
 7   Dialogs;
 8 
 9 type
10   TForm1 = class(TForm)
11     procedure FormPaint(Sender: TObject);
12   end;
13 
14 var
15   Form1: TForm1;
16 
17 implementation
18 
19 {$R *.dfm}
20 
21 uses GDIPOBJ, GDIPAPI;
22 
23 procedure TForm1.FormPaint(Sender: TObject);
24 var
25   g: TGPGraphics;
26   p: TGPPen;
27 begin
28   g := TGPGraphics.Create(Canvas.Handle);
29   p := TGPPen.Create(clWebSkyBlue, 2);
30   g.Clear(MakeColor(255,255,255));
31 
32   //g.SetSmoothingMode(SmoothingModeHighQuality);  
33   //SmoothingModeHighQuality也可用SmoothingModeAntiAlias代替，至今不明白它们有什么区别。SmoothingModeHighQuality=2，SmoothingModeAntiAlias=4
34 
35   g.DrawLine(p, 0, 0, 100, 100);
36   g.DrawLine(p, MakePoint(0,10), MakePoint(100,110));
37 
38   g.Free;
39   p.Free;
40 end;
41 
42 end.

 

绘图质量参数：

SmoothingModeInvalid = -1; 指定一个无效模式
SmoothingModeDefault = 0; 指定不消除锯齿
SmoothingModeHighSpeed = 1; 指定高速度、低质量呈现
SmoothingModeHighQuality = 2; 指定高质量、低速度呈现
SmoothingModeNone = 3; 指定不消除锯齿
SmoothingModeAntiAlias = 4; 指定消除锯齿的呈现