unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, DXDraws, StdCtrls, DirectX;

type
  TForm1 = class(TForm)
    DXDraw1: TDXDraw;
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

const
  ImgPath1 = 'C:\Temp\DelphiX.bmp';
  ImgPath2 = 'C:\Temp\Test.bmp';

procedure TForm1.Button1Click(Sender: TObject);
var
  MySurface: TDirectDrawSurface;
  DF: TDDBltFX;
begin
  MySurface := TDirectDrawSurface.Create(DXDraw1.DDraw);
  MySurface.LoadFromFile(ImgPath1);
  DXDraw1.Surface.LoadFromFile(ImgPath2);
  DF.dwSize := SizeOf(DF);
  DF.dwDDFX := 0;
  DXDraw1.Surface.Blt(Rect(0, 0, MySurface.Width div 2, MySurface.Height div 2),
                      MySurface.ClientRect,
                      DDBLT_KEYSRC or DDBLT_WAIT,
                      DF,
                      MySurface);
  DXDraw1.Flip;
  FreeAndNil(MySurface);
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  MySurface: TDirectDrawSurface;
begin
  MySurface := TDirectDrawSurface.Create(DXDraw1.DDraw);
  MySurface.LoadFromFile(ImgPath1);
  DXDraw1.Surface.LoadFromFile(ImgPath2);
  DXDraw1.Surface.BltFast(0, 0,
    Bounds(16, 4, Trunc(MySurface.Width * 0.9), Trunc(MySurface.Height * 0.9)),
    DDBLTFAST_SRCCOLORKEY or DDBLTFAST_WAIT,
    MySurface);
  DXDraw1.Flip;
  FreeAndNil(MySurface);
end;

end.