再学GDI+[51]: 路径 - IsVisible、IsOutlineVisible

再学GDI+[51]: 路径 - IsVisible、IsOutlineVisible2012-05-10 cnblogs 万一本例效果图:

代码文件:

unit Unit1;
interface
uses
 Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
 Dialogs;
type
 TForm1 = class（TForm）
  procedure FormCreate（Sender: TObject）;
  procedure FormDestroy（Sender: TObject）;
  procedure FormPaint（Sender: TObject）;
  procedure FormMouseMove（Sender: TObject; Shift: TShiftState; X, Y: Integer）;
 end;
var
 Form1: TForm1;
implementation
{$R *.dfm}
uses GDIPOBJ, GDIPAPI;
var
 path1,path2,path3: TGPGraphicsPath;
 p: TGPPen;
procedure TForm1.FormCreate（Sender: TObject）;
var
 r: TRect;
begin
 path1 := TGPGraphicsPath.Create;
 path2 := TGPGraphicsPath.Create;
 path3 := TGPGraphicsPath.Create;
 p := TGPPen.Create（aclRed, 3）;
 path1.AddLine（0, 0, ClientWidth, ClientHeight）;
 r := ClientRect;
 InflateRect（r, -ClientWidth div 3, -ClientHeight div 3）;
 OffsetRect（r, -Trunc（（r.Right-r.Left） * 0.6）, -Trunc（（r.Bottom-r.Top） * 0.6））;
 path2.AddRectangle（MakeRect（r））;
 OffsetRect（r, r.Right-r.Left, r.Bottom-r.Top）;
 path3.AddEllipse（MakeRect（r））;
end;
procedure TForm1.FormDestroy（Sender: TObject）;
begin
 path1.Free;
 path2.Free;
 path3.Free;
 p.Free;
end;
procedure TForm1.FormPaint（Sender: TObject）;
var
 g: TGPGraphics;
begin
 g := TGPGraphics.Create（Canvas.Handle）;
 g.DrawPath（p, path1）;
 g.DrawPath（p, path2）;
 g.DrawPath（p, path3）;
 g.Free;
end;
procedure TForm1.FormMouseMove（Sender: TObject; Shift: TShiftState; X,
 Y: Integer）;
begin
 Text := "";
// if path1.IsVisible（MakePoint（X,Y）） then Text := "在 path1 内";
 if path2.IsVisible（MakePoint（X,Y）） then Text := "在矩形内";
 if path3.IsVisible（MakePoint（X,Y）） then Text := "在椭圆内";
 if path1.IsOutlineVisible（X, Y, p） then Text := "在直线上";
 if path2.IsOutlineVisible（X, Y, p） then Text := "在矩形的边线上";
 if path3.IsOutlineVisible（X, Y, p） then Text := "在椭圆的圆周线上";
end;
end.

窗体文件:

object Form1: TForm1
 Left = 0
 Top = 0
 Caption = "Form1"
 ClientHeight = 206
 ClientWidth = 339
 Color = clBtnFace
 Font.Charset = DEFAULT_CHARSET
 Font.Color = clWindowText
 Font.Height = -11
 Font.Name = "Tahoma"
 Font.Style = []
 OldCreateOrder = False
 Position = poDesktopCenter
 OnCreate = FormCreate
 OnDestroy = FormDestroy
 OnMouseMove = FormMouseMove
 OnPaint = FormPaint
 PixelsPerInch = 96
 TextHeight = 13
end