為什么80%的碼農都做不了架構師？>>> ??

本例效果圖:

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代碼文件:

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unit Unit1;interfaceusesWindows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,Dialogs;typeTForm1 = class(TForm)procedure FormPaint(Sender: TObject);procedure FormCreate(Sender: TObject);procedure FormDestroy(Sender: TObject);procedure FormMouseDown(Sender: TObject; Button: TMouseButton;Shift: TShiftState; X, Y: Integer);procedure FormMouseMove(Sender: TObject; Shift: TShiftState; X, Y: Integer);procedure FormMouseUp(Sender: TObject; Button: TMouseButton;Shift: TShiftState; X, Y: Integer);end;varForm1: TForm1;implementation{$R *.dfm}uses GDIPOBJ, GDIPAPI;varimg: TGPImage;pts: array[0..2] of TGPPoint;flag: Integer = -1;procedure TForm1.FormCreate(Sender: TObject); varw,h: Integer; beginimg := TGPImage.Create('C:\temp\test.jpg');w := img.GetWidth;h := img.GetHeight;pts[0] := MakePoint((ClientWidth - w) div 2 + w, (ClientHeight - h) div 2);pts[1] := MakePoint((ClientWidth - w) div 2, (ClientHeight - h) div 2);pts[2] := MakePoint((ClientWidth - w) div 2 + w, (ClientHeight - h) div 2 + h);DoubleBuffered := True; end;procedure TForm1.FormDestroy(Sender: TObject); beginimg.Free; end;procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;Shift: TShiftState; X, Y: Integer); vari: Integer; beginfor i := 0 to Length(pts) doif PtInRect(Bounds(pts[i].X-3, pts[i].Y-3, 6, 6), Point(X, Y)) thenbeginflag := i;Exit;end; end;procedure TForm1.FormMouseMove(Sender: TObject; Shift: TShiftState; X,Y: Integer); beginif flag = -1 then Exit;pts[flag] := MakePoint(X, Y);Repaint; end;procedure TForm1.FormMouseUp(Sender: TObject; Button: TMouseButton;Shift: TShiftState; X, Y: Integer); beginflag := -1; end;procedure TForm1.FormPaint(Sender: TObject); varg: TGPGraphics;p: TGPPen;i: Integer; beging := TGPGraphics.Create(Self.Canvas.Handle);p := TGPPen.Create(aclRed);{第一點: 右上角; 第二點: 左上角; 第三點: 右下角; 第四點將根據平行四邊形計算; 只能是三個點.}g.DrawImage(img, PGPPoint(@pts), Length(pts));for i := 0 to Length(pts)-1 do g.DrawRectangle(p, pts[i].X-3, pts[i].Y-3, 6, 6);p.Free;g.Free; end;end. 窗體文件:

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object Form1: TForm1Left = 0Top = 0Caption = 'Form1'ClientHeight = 206ClientWidth = 307Color = clBtnFaceFont.Charset = DEFAULT_CHARSETFont.Color = clWindowTextFont.Height = -11Font.Name = 'Tahoma'Font.Style = []OldCreateOrder = FalsePosition = poDesktopCenterOnCreate = FormCreateOnDestroy = FormDestroyOnMouseDown = FormMouseDownOnMouseMove = FormMouseMoveOnMouseUp = FormMouseUpOnPaint = FormPaintPixelsPerInch = 96TextHeight = 13 end

轉載于:https://my.oschina.net/hermer/blog/319935

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