Delphi与DirectX之DelphiX(83): TDIB.FilterLine()、FilterRect();

本例效果图:

代码文件:

unit Unit1;
interface
uses
　 Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
　 Dialogs, DIB, StdCtrls;
type
　 TForm1 = class(TForm)
　　 DXPaintBox1: TDXPaintBox;
　　 Button1: TButton;
　　 procedure FormCreate(Sender: TObject);
　　 procedure FormDestroy(Sender: TObject);
　　 procedure Button1Click(Sender: TObject);
　 end;
var
　 Form1: TForm1;
implementation
{$R *.dfm}
uses TypInfo;
var
　 dib: TDIB;
　 f: Integer;
procedure TForm1.Button1Click(Sender: TObject);
const
　 clr = clRed;
var
　 w,h,a,b: Integer;
begin
　 DXPaintBox1.DIB.Assign(dib);
　 w := DXPaintBox1.ClientWidth;
　 h := DXPaintBox1.ClientHeight;
　 a := w div 7;
　 b := h div 7;
　 DXPaintBox1.DIB.FilterLine(0, b, w, b, clr, TFilterMode(f));
　 DXPaintBox1.DIB.FilterLine(0, h-b, w, h-b, clr, TFilterMode (f));
　 DXPaintBox1.DIB.FilterLine(a, 0, a, h, clr, TFilterMode(f));
　 DXPaintBox1.DIB.FilterLine(w-a, 0, w-a, h, clr, TFilterMode (f));
　 DXPaintBox1.DIB.FilterRect(w div 5, h div 5, w div 5*3, h div 5*3, clr, TFilterMode(f));
　 DXPaintBox1.Repaint;
　 Text := GetEnumName(TypeInfo(TFilterMode), f);
　 Inc(f); f := f and 3;
end;
procedure TForm1.FormCreate(Sender: TObject);
const
　 ImgPath1 = 'C:\Temp\DX.jpg';
begin
　 dib := TDIB.Create;
　 dib.LoadFromFile(ImgPath1);
　 DXPaintBox1.DIB.Assign(dib);
　 DXPaintBox1.Width := dib.Width;
　 DXPaintBox1.Height := dib.Height;
　 DXPaintBox1.Repaint;
end;
procedure TForm1.FormDestroy(Sender: TObject);
begin
　 dib.Free;
end;
end.