Delphi 与 DirectX 之 DelphiX(13): TPictureCollectionItem.DrawRotate

本例效果图(实际效果是相当流畅的, gif 只能说明个动作趋势):

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代码文件:

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unit Unit1;



interface



uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, DXDraws, StdCtrls, DXClass, ComCtrls;



type

  TForm1 = class(TForm)

    DXDraw1: TDXDraw;

    DXImageList1: TDXImageList;

    DXTimer1: TDXTimer;

    procedure FormCreate(Sender: TObject);

    procedure DXTimer1Timer(Sender: TObject; LagCount: Integer);

  end;



var

  Form1: TForm1;



implementation



{$R *.dfm}



var

  PicItem: TPictureCollectionItem;

  Angle: Cardinal;



procedure TForm1.FormCreate(Sender: TObject);

const

  ImgPath1 = 'C:\Temp\DelphiX.bmp';

begin

  DXDraw1.Align := alClient;

  DXTimer1.Interval := 0;

  DXImageList1.DXDraw := DXDraw1;

  PicItem := TPictureCollectionItem(DXImageList1.Items.Add);

  PicItem.Picture.LoadFromFile(ImgPath1);

end;



procedure TForm1.DXTimer1Timer(Sender: TObject; LagCount: Integer);

begin

  DXDraw1.Surface.Fill(0);

  PicItem.DrawRotate(DXDraw1.Surface,

                     DXDraw1.Width div 2, DXDraw1.Height div 2, {位置}

                     PicItem.Width, PicItem.Height,             {大小}

                     0,                                         {调色板}

                     0.5, 0.5,                                  {旋转中心: 0..1}

                     Byte(Angle));                              {旋转角度 0..255}

  Inc(Angle);

  DXDraw1.Flip;

end;



end.