如何在桌面画坐标系？？？急，急，急高分求解.

Question

现在要在Windows桌面画一个十字坐标系，并显示屏幕该点象素的坐标值及RGB值。应该如何下手啊。请各位帮忙了。

Answer 1

看一看抓图软件的源码就会了~~
baidu里面搜索一下

Answer 2

用这个TScreen.Canvas，就和delphi普通窗口一样。

Answer 3

unit Unit1;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, Menus, ExtCtrls;type
  TForm1 = class(TForm)
    PaintBox1: TPaintBox;
    MainMenu1: TMainMenu;
    z1: TMenuItem;
    sin1: TMenuItem;
    cos1: TMenuItem;
    cls1: TMenuItem;
    exit1: TMenuItem;
    procedure FormPaint(Sender: TObject);
    procedure exit1Click(Sender: TObject);
    procedure sin1Click(Sender: TObject);
    procedure cls1Click(Sender: TObject);
    procedure cos1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  Form1: TForm1;implementation{$R *.dfm}procedure TForm1.FormPaint(Sender: TObject);
var oldx,oldy,xt,yt:integer;
    st:real;
    //rect1:trect;
    const pi=3.14159;
begin
   paintbox1.Top:=0;
   paintbox1.Left:=0;
   paintbox1.Width:=form1.clientWidth;
   paintbox1.Height:=form1.clientHeight;
   canvas.Pen.Color:=clblack;   oldx:=round(form1.ClientWidth/2);
   oldy:=round(form1.ClientHeight/2);
   paintbox1.Canvas.MoveTo(oldx,0);
   paintbox1.Canvas.LineTo(oldx,paintbox1.Height);
   paintbox1.Canvas.MoveTo(0,oldy);
   paintbox1.Canvas.LineTo(paintbox1.Width,oldy);   for xt:=-9 to 9 do
     if xt<>0 then
     begin
      st:=xt*10*pi;
      paintbox1.Canvas.MoveTo(oldx+round(st),oldy-1);
      paintbox1.Canvas.LineTo(oldx+round(st),oldy);
      paintbox1.Canvas.TextOut(oldx+round(st)-10,oldy+1,inttostr(xt)+'/2π');
   end;
   for yt:=-9 to 9 do
   if yt<>0 then
   begin
    st:=yt*20;
    paintbox1.Canvas.MoveTo(oldx+1,oldy+round(st));
    paintbox1.Canvas.LineTo(oldx,oldy+round(st));
    paintbox1.Canvas.TextOut(oldx-20,oldy+round(st),inttostr(yt));
  end;
end;procedure TForm1.exit1Click(Sender: TObject);
begin
form1.Free;
end;procedure TForm1.sin1Click(Sender: TObject);
var oldx,oldy,t:integer;
xt,yt:real;
begin
  oldx:=round(form1.ClientWidth/2);
  oldy:=round(form1.ClientHeight/2);
  for t:=-oldx to oldx do
  begin
   xt:=t/20;
   yt:=sin(xt);
  paintbox1.Canvas.Pixels[t+oldx,oldy+round(yt*20)]:=clblack;
  end;
end;procedure TForm1.cls1Click(Sender: TObject);
begin
paintbox1.Refresh;
end;procedure TForm1.cos1Click(Sender: TObject);
var oldx,oldy,t:integer;
xt,yt:real;
begin
  oldx:=round(form1.ClientWidth/2);
  oldy:=round(form1.ClientHeight/2);
  for t:=-oldx to oldx do
  begin
   xt:=t/20;
   yt:=cos(xt);
  paintbox1.Canvas.Pixels[t+oldx,oldy+round(yt*20)]:=clblack;
  end;
end;end.
这个怎么样............

Answer 4

ls的好像结果不满足lz的要求哦
lz可以考虑一下先把屏幕截取下来，然后对截取的屏幕转换成位图再操作，我这里有个类似的例子，lz想要的话留下EMail哈

Answer 5

[email protected]发我这个邮箱吧。谢谢