Программирование на delphi api directx 9

program game3dArena;
{$IFNDEF __TMT__}
{$IFNDEF FPC}
  // *** Borland compilers support ***
  {$DEFINE BORLAND}
  {$DEFINE TYPE_IDENTITY}
  {$DEFINE SUPPORTS_EXCEPTIONS}
  {$IFDEF COMPILER6_UP}
    {$DEFINE SUPPORTS_EXPL_ENUMS} // Enumerated types with explicitly assigned ordinality
    {$IFNDEF BCB6_UP}
      // C++Builder6 hack: Delphi 6-7 compilers have bugged .HPP generation for
      // enums in some cases (and D6 compiler is included with BCB6)
      {$DEFINE SUPPORTS_EXPL_ENUMS_except_BCB6}
    {$ENDIF}
  {$ENDIF}
  // Additional settings
  {$MINENUMSIZE 4}
  {$ALIGN ON}
  {$IFDEF COMPILER7_UP}
    {$WARN UNSAFE_CODE Off}
    {$WARN UNSAFE_TYPE OFF}
    {$WARN UNSAFE_CAST OFF}
  {$ENDIF}
  {$IFDEF COMPILER9_UP}
    {$IFDEF DEBUG}
      {$INLINE OFF}
    {$ELSE}
      {$INLINE ON}
    {$ENDIF}
  {$ENDIF}
{$ELSE}
  // *** FreePascal compiler support ***
  {$INCLUDE Jedi.inc}
  {$APPTYPE GUI}
 {$UNDEF TYPE_IDENTITY}
  {$DEFINE SUPPORTS_EXCEPTIONS}
  {$DEFINE SUPPORTS_DEFAULTPARAMS}
 /{$DEFINE SUPPORTS_OVERLOAD}
  // Additional settings
  {$MODE DELPHI}
  {$H+} // Long Strings
  {$MINENUMSIZE 6}
  {$ALIGN ON}
  {$PACKRECORDS 8}
  {$INLINE ON}
  {$DEFINE SUPPORTS_INLINE}
 // {$DEFINE COMPILER5_UP} // Specially for DirectDraw.pas
{$ENDIF}
{$ELSE}
  // *** TMT Pascal compiler support ***
  {$I TMT.inc}
  // TMT compiler support
  {$IFNDEF __TMT__}
//    TMT pascal compiler required here
  {$ENDIF}
  // ADD IFOPT for TMT
  {$DEFINE TMT}
  {$IFDEF __WIN32__}
    {$DEFINE WIN32}
  {$ENDIF}
  {$IFDEF __VER5__}
    {$DEFINE TMT5}
    {$DEFINE TMT5_UP}
    {$DEFINE TMT4_UP}
    {$DEFINE TMT3_UP}
  {$ENDIF}
  {$IFDEF __VER4__}
    {$DEFINE TMT4}
    {$DEFINE TMT4_UP}
    {$DEFINE TMT3_UP}
  {$ENDIF}
  {$IFDEF __VER3__}
    {$DEFINE TMT3}
    {$DEFINE TMT3_UP}
  {$ENDIF}
  {$IFDEF TMT4_UP}
    {$DEFINE SUPPORTS_INTERFACE}
  {$ENDIF}
  // Additional settings
  {$A+}  // Word alignment data
  {$OA+} // Objects and structures align
  {$Z8}  // Set minimum size of enumerated type to 4
{$ENDIF}
// By default use most recent DirectX sub-version
{$IFNDEF DX81}
  {$IFNDEF DX80}
    {$DEFINE DX81}
  {$ENDIF}
{$ENDIF}
{$IFNDEF DX92}
  {$IFNDEF DX91}
    {$IFNDEF DX90}
      {$DEFINE DX92}
    {$ENDIF}
  {$ENDIF}
{$ENDIF}
{$IFDEF BORLAND}
{$R 'winmain.res' 'winmain.rc'}
{%File 'MultiAnimation.fx'}
{$ENDIF}
 {$MINENUMSIZE 4}
{$ALIGN ON}
uses
  Windows,classes,d3dx9,
  graphics  ;

{$MINENUMSIZE 4}
{$ALIGN ON}
 
unit D3DX9;
 
interface
  uses types;
Как эти директивы работают я не знаю .
В коде чаcто встречаетcя директива   {$EXTERNALSYM}
Часто встречается 
{$IFDEF VER9x}
    procedure Progress(Sender: TObject; Stage: TProgressStage;
      PercentDone: Byte;  RedrawNow: Boolean; const R: TRect; const Msg: string); dynamic;
{$ENDIF}

{$MINENUMSIZE 1}
 
type
  // Vertex element semantics
  //
  _D3DDECLUSAGE = (
    D3DDECLUSAGE_POSITION,      // = 0
    D3DDECLUSAGE_BLENDWEIGHT,   // 1
    D3DDECLUSAGE_BLENDINDICES,  // 2
    D3DDECLUSAGE_NORMAL,        // 3
    D3DDECLUSAGE_PSIZE,         // 4
    D3DDECLUSAGE_TEXCOORD,      // 5
    D3DDECLUSAGE_TANGENT,       // 6
    D3DDECLUSAGE_BINORMAL,      // 7
    D3DDECLUSAGE_TESSFACTOR,    // 8
    D3DDECLUSAGE_POSITIONT,     // 9
    D3DDECLUSAGE_COLOR,         // 10
    D3DDECLUSAGE_FOG,           // 11
    D3DDECLUSAGE_DEPTH,         // 12
    D3DDECLUSAGE_SAMPLE         // 13
  );
  {$EXTERNALSYM _D3DDECLUSAGE}
  D3DDECLUSAGE = _D3DDECLUSAGE;
  {$EXTERNALSYM D3DDECLUSAGE}
  TD3DDeclUsage = _D3DDECLUSAGE;
 
const
  MAXD3DDECLUSAGE         = DWORD(D3DDECLUSAGE_SAMPLE);
 // {$EXTERNALSYM MAXD3DDECLUSAGE}
  MAXD3DDECLUSAGEINDEX    = 15;
 // {$EXTERNALSYM MAXD3DDECLUSAGEINDEX}
 
 // {$EXTERNALSYM MAXD3DDECLLENGTH}
type
  _D3DDECLMETHOD = (
    D3DDECLMETHOD_DEFAULT,    // = 0,
    D3DDECLMETHOD_PARTIALU,
    D3DDECLMETHOD_PARTIALV,
    D3DDECLMETHOD_CROSSUV,    // Normal
    D3DDECLMETHOD_UV,
    D3DDECLMETHOD_LOOKUP,               // Lookup a displacement map
    D3DDECLMETHOD_LOOKUPPRESAMPLED      // Lookup a pre-sampled displacement map
  );
  {$EXTERNALSYM _D3DDECLMETHOD}
  D3DDECLMETHOD = _D3DDECLMETHOD;
  {$EXTERNALSYM D3DDECLMETHOD}
  TD3DDeclMethod = _D3DDECLMETHOD;
const
  MAXD3DDECLMETHOD = DWORD(D3DDECLMETHOD_LOOKUPPRESAMPLED);
  {$EXTERNALSYM MAXD3DDECLMETHOD}
type
  // Declarations for _Type fields
  //
  _D3DDECLTYPE = (
    D3DDECLTYPE_FLOAT1    =  0,  // 1D float expanded to (value, 0., 0., 1.)
    D3DDECLTYPE_FLOAT2    =  1,  // 2D float expanded to (value, value, 0., 1.)
    D3DDECLTYPE_FLOAT3    =  2,  // 3D float expanded to (value, value, value, 1.)
    D3DDECLTYPE_FLOAT4    =  3,  // 4D float
    D3DDECLTYPE_D3DCOLOR  =  4,  // 4D packed unsigned bytes mapped to 0. to 1. range
                                 // Input is in D3DCOLOR format (ARGB) expanded to (R, G, B, A)
    D3DDECLTYPE_UBYTE4    =  5,  // 4D unsigned byte
    D3DDECLTYPE_SHORT2    =  6,  // 2D signed short expanded to (value, value, 0., 1.)
    D3DDECLTYPE_SHORT4    =  7,  // 4D signed short
  // The following types are valid only with vertex shaders >= 2.0
    D3DDECLTYPE_UBYTE4N   =  8,  // Each of 4 bytes is normalized by dividing to 255.0
    D3DDECLTYPE_SHORT2N   =  9,  // 2D signed short normalized (v[0]/32767.0,v[1]/32767.0,0,1)
    D3DDECLTYPE_SHORT4N   = 10,  // 4D signed short normalized (v[0]/32767.0,v[1]/32767.0,v[2]/32767.0,v[3]/32767.0)
    D3DDECLTYPE_USHORT2N  = 11,  // 2D unsigned short normalized (v[0]/65535.0,v[1]/65535.0,0,1)
    D3DDECLTYPE_USHORT4N  = 12,  // 4D unsigned short normalized (v[0]/65535.0,v[1]/65535.0,v[2]/65535.0,v[3]/65535.0)
    D3DDECLTYPE_UDEC3     = 13,  // 3D unsigned 10 10 10 format expanded to (value, value, value, 1)
    D3DDECLTYPE_DEC3N     = 14,  // 3D signed 10 10 10 format normalized and expanded to (v[0]/511.0, v[1]/511.0, v[2]/511.0, 1)
    D3DDECLTYPE_FLOAT16_2 = 15,  // Two 16-bit floating point values, expanded to (value, value, 0, 1)
    D3DDECLTYPE_FLOAT16_4 = 16,  // Four 16-bit floating point values
    D3DDECLTYPE_UNUSED    = 17   // When the type field in a decl is unused.
  );
 
// Restores enums to be 4 byte in size
{$MINENUMSIZE 4}
const
  MAXD3DDECLTYPE      = DWORD(D3DDECLTYPE_UNUSED);
  {$EXTERNALSYM MAXD3DDECLTYPE}