Рисование линий, Как в Paint
Материал из DRKB
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, ToolWin, ComCtrls, ExtCtrls;
type
TForm1 = class(TForm)
Image1: TImage;
procedure FormCreate(Sender: TObject);
procedure FormMouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
procedure FormMouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
procedure FormMouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer);
private
{ Private declarations }
StartX: Integer;
StartY: Integer;
EndX: Integer;
EndY: Integer;
isMousePressed: Boolean;
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.FormCreate(Sender: TObject);
begin
isMousePressed := False;
Image1.Picture.Bitmap := TBitmap.create();
Image1.Picture.Bitmap.Width := Image1.Width;
Image1.Picture.Bitmap.Height := Image1.Height
end;
procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
StartX := X;
StartY := Y;
EndX := StartX;
EndY := StartY;
isMousePressed := True
end;
procedure TForm1.FormMouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
isMousePressed := False;
Image1.Picture.Bitmap.Canvas.Pen.Mode := pmNOT;
Image1.Picture.Bitmap.Canvas.moveTo(StartX, StartY);
Image1.Picture.Bitmap.Canvas.lineTo(EndX, EndY);
Image1.Picture.Bitmap.Canvas.Pen.Mode := pmCopy;
EndX := X;
EndY := Y;
Image1.Picture.Bitmap.Canvas.MoveTo(StartX, StartY);
Image1.Picture.Bitmap.Canvas.LineTo(EndX, EndY)
end;
procedure TForm1.FormMouseMove(Sender: TObject; Shift: TShiftState; X, Y: Integer);
begin
if isMousePressed then
begin
Image1.Picture.Bitmap.Canvas.Pen.Mode := pmNOT;
Image1.Picture.Bitmap.Canvas.MoveTo(StartX, StartY);
Image1.Picture.Bitmap.Canvas.LineTo(EndX, EndY);
EndX := X;
EndY := Y;
Image1.Picture.Bitmap.Canvas.MoveTo(StartX, StartY);
Image1.Picture.Bitmap.Canvas.LineTo(EndX, EndY);
Image1.Picture.Bitmap.Canvas.Pen.Mode := pmCopy
end
end;
end.
Более развернутую демку можно найти в папке {$DELPHI7}/Demos/Doc/Graphex
Author: Mischka
Source: http://forum.sources.ru
ID: 03825