Delphi 与 DirectX 之 DelphiX(18): TDXDraw 中描绘图片的命令

前面的绘图命令都是来自 TDXImageList,
准确地说是来自 TDXImageList.Items 所包含的 TPictureCollectionItem 对象.

那 TDXDraw 本身有没有绘图命令呢?
TDXDraw 本身没有绘图命令, 但它的有绘图表面(TDirectDrawSurface), 譬如: Surface、Primary;
TDXDraw 的绘图表面有更多的绘图命令, 另外 TDXDraw 可以多个绘图表面.

TDirectDrawSurface 的绘图命令和 TPictureCollectionItem 的绘图命令最大的区别是它们的图像来源;
TDirectDrawSurface 的图像来源必须是另一个已绘制好的 TDirectDrawSurface 对象.

这里列举的只是 TDirectDrawSurface 和 TPictureCollectionItem 类似的描绘图片的命令:
 
   


TDirectDrawSurface.Draw();

TDirectDrawSurface.StretchDraw();

TDirectDrawSurface.DrawAdd();

TDirectDrawSurface.DrawAlpha();

TDirectDrawSurface.DrawSub();

TDirectDrawSurface.DrawAddCol();

TDirectDrawSurface.DrawAlphaCol();

TDirectDrawSurface.DrawSubCol();

TDirectDrawSurface.DrawRotate();

TDirectDrawSurface.DrawRotateAdd();

TDirectDrawSurface.DrawRotateAdd();

TDirectDrawSurface.DrawRotateAlpha();

TDirectDrawSurface.DrawRotateSub();

TDirectDrawSurface.DrawRotateAddCol();

TDirectDrawSurface.DrawRotateAlphaCol();

TDirectDrawSurface.DrawRotateCol();

TDirectDrawSurface.DrawRotateSubCol();

TDirectDrawSurface.DrawWaveX();

TDirectDrawSurface.DrawWaveXAdd();

TDirectDrawSurface.DrawWaveXAlpha();

TDirectDrawSurface.DrawWaveXSub();

TDirectDrawSurface.DrawWaveY();

TDirectDrawSurface.DrawWaveYAdd();

TDirectDrawSurface.DrawWaveYAlpha();

TDirectDrawSurface.DrawWaveYSub();


 
   

本例效果图:

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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;



type

  TForm1 = class(TForm)

    DXDraw1: TDXDraw;

    DXImageList1: TDXImageList;

    Button1: TButton;

    Button2: TButton;

    procedure FormCreate(Sender: TObject);

    procedure Button1Click(Sender: TObject);

    procedure Button2Click(Sender: TObject);

  end;



var

  Form1: TForm1;



implementation



{$R *.dfm}



var

  PicItem: TPictureCollectionItem;



procedure TForm1.FormCreate(Sender: TObject);

const

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

begin

  DXImageList1.DXDraw := DXDraw1;

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

  PicItem.Picture.LoadFromFile(ImgPath1);

end;



procedure TForm1.Button1Click(Sender: TObject);

var

  MySurface: TDirectDrawSurface;

begin

  MySurface := TDirectDrawSurface.Create(DXDraw1.DDraw);

  PicItem.Restore; {Surface.Draw 的矩形范围好像能直接作用到列表中的图片, 需要恢复一下}

  MySurface.SetSize(PicItem.Width, PicItem.Height);

  MySurface.Fill(0);

  PicItem.Draw(MySurface, 0, 0, 0);



  DXDraw1.Surface.Fill(0);

  DXDraw1.Surface.Draw((DXDraw1.Width - MySurface.Width) div 2,

                       (DXDraw1.Height - MySurface.Height) div 2,

                       MySurface);

  DXDraw1.Flip;

  FreeAndNil(MySurface);

end;



procedure TForm1.Button2Click(Sender: TObject);

var

  MySurface: TDirectDrawSurface;

  m,n: Integer;

begin

  m := 40; n := 15;

  MySurface := TDirectDrawSurface.Create(DXDraw1.DDraw);

  PicItem.Restore; {Surface.Draw 的矩形范围好像能直接作用到列表中的图片, 需要恢复一下}

  MySurface.SetSize(PicItem.Width, PicItem.Height);

  MySurface.Fill(0);

  PicItem.Draw(MySurface, 0, 0, 0);



  DXDraw1.Surface.Fill(0);

  DXDraw1.Surface.Draw((DXDraw1.Width - MySurface.Width) div 2 + m,

                       (DXDraw1.Height - MySurface.Height) div 2 + n,

                       Bounds(m, n, MySurface.Width - m*2, MySurface.Height - n*2),

                       MySurface);

  DXDraw1.Flip;

  FreeAndNil(MySurface);

end;



end.