再学GDI+[50]: 路径 - GetPathPoints、GetPathTypes、TPathData

再学GDI+[50]: 路径 - GetPathPoints、GetPathTypes、TPathData2012-05-09 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, StdCtrls, Grids;
type
 TForm1 = class（TForm）
  StringGrid1: TStringGrid;
  procedure FormCreate（Sender: TObject）;
  procedure FormPaint（Sender: TObject）;
  procedure StringGrid1SelectCell（Sender: TObject; ACol, ARow: Integer;
   var CanSelect: Boolean）;
 end;
var
 Form1: TForm1;
implementation
{$R *.dfm}
uses GDIPOBJ, GDIPAPI;
procedure TForm1.FormCreate（Sender: TObject）;
begin
 StringGrid1.Align := alRight;
 StringGrid1.FixedCols := 0;
 StringGrid1.ColCount := 3;
 StringGrid1.ColWidths[0] := 25;
 StringGrid1.ColWidths[1] := 25;
 StringGrid1.ColWidths[2] := 80;
 StringGrid1.DefaultRowHeight := 20;
 StringGrid1.Cells[0,0] := "X";
 StringGrid1.Cells[1,0] := "Y";
 StringGrid1.Cells[2,0] := "点类型";
end;
procedure TForm1.FormPaint（Sender: TObject）;
var
 g: TGPGraphics;
 p: TGPPen;
 path: TGPGraphicsPath;
 points: array of TGPPoint;
 types: PByte;
 typestr: string;
 i: Integer;
begin
 g := TGPGraphics.Create（Canvas.Handle）;
 p := TGPPen.Create（aclRed）;
 path := TGPGraphicsPath.Create;
 path.StartFigure;
 path.AddRectangle（MakeRect（30,20,90,40））;
 path.AddEllipse（MakeRect（30,80,90,180））;
 path.CloseFigure;
 g.DrawPath（p, path）;
 SetLength（points, path.GetPointCount）;
 GetMem（types, path.GetPointCount）;
 path.GetPathPoints（PGPPoint（points）, Length（points））;
 path.GetPathTypes（types, Length（points））;
 StringGrid1.RowCount := Length（points） + 1;
 for i := 0 to Length（points） - 1 do
 begin
  case types^ of
   $00 : typestr := "路径起始点";
   $01 : typestr := "直线点";
   $03 : typestr := "贝塞尔线点";
   $07 : typestr := "遮盖点";
   $10 : typestr := "虚线点";
   $20 : typestr := "路径标记";
   $80 : typestr := "子路径结束点";
  end;
  StringGrid1.Cells[0, i+1] := IntToStr（points[i].X）;
  StringGrid1.Cells[1, i+1] := IntToStr（points[i].Y）;
  StringGrid1.Cells[2, i+1] := typestr;
  Inc（types）;
 end;
 Dec（types, Length（points））;
 FreeMem（types）;
 types := nil;
 path.Free;
 p.Free;
 g.Free;
end;
procedure TForm1.StringGrid1SelectCell（Sender: TObject; ACol, ARow: Integer;
 var CanSelect: Boolean）;
var
 x,y: Integer;
begin
 x := StrToIntDef（StringGrid1.Cells[0,ARow], 0）;
 y := StrToIntDef（StringGrid1.Cells[1,ARow], 0）;
 Repaint;
 Canvas.Brush.Color := clBlue;
 Canvas.FillRect（Bounds（x-3,y-3,6,6））;
 Text := Format（"%d,%d",[x,y]）;
end;
end.