以下代码在vc 7.1(vs.net2003)下编译通过。
使用模板偏特化实现
#ifndef _AI_D3DFVF_H_
#define _AI_D3DFVF_H_
//D3d9Fvf struct generate templates
//Author Kevinqing <qingzl@cdgwbn.com.cn>
//
#include <d3d9.h>
//-----------posoition-------------
namespace _D3DFvf{
template <bool b>struct pos_t;
template <> struct pos_t<true>{
union {
D3DVECTOR v;
struct{
float x,y,z;
};
};
};
//-----------RHW-------------------
template <bool b>struct rhw_t;
template <> struct rhw_t<false>{};
template <> struct rhw_t<true>{
float rhw;
};
//-----------W---------------------
template <bool b>struct w_t;
template <> struct w_t<false>{};
template <> struct w_t<true>{
DWORD w;
};
//-----------normal----------------
template <bool b>struct n_t;
template <> struct n_t<false>{};
template <> struct n_t<true>{
D3DVECTOR n;
};
//-----------psize-----------------
template <bool b>struct psize_t;
template <> struct psize_t<false>{};
template <> struct psize_t<true>{
float psize;
};
//-----------diff-------------------
template <bool b>struct diff_t;
template <> struct diff_t<false>{};
template <> struct diff_t<true>{
D3DCOLOR diff;
};
//-----------spec-------------------
template <bool b>struct spec_t;
template <> struct spec_t<false>{};
template <> struct spec_t<true>{
D3DCOLOR spec;
};
#define TestFlag(a,b,m) (bool((a&m)==b))
#define tp(a,b) TestFlag(a,b,D3DFVF_POSITION_MASK)
#define TestMask(a,b) (bool((a&b)!=0))
//----------b/i----------------------
#define IsXYZBn(a) (tp(a,D3DFVF_XYZB1)||tp(a,D3DFVF_XYZB2)||tp(a,D3DFVF_XYZB3)||tp(a,D3DFVF_XYZB4)||tp(a,D3DFVF_XYZB5))
#define XYZBn(a) (tp(a,D3DFVF_XYZB1)? 1:(tp(a,D3DFVF_XYZB2)? 2:(tp(a,D3DFVF_XYZB3)? 3:(tp(a,D3DFVF_XYZB4)? 4:(tp(a,D3DFVF_XYZB5)? 5:0)))))
template <bool b,int i>struct b_t;
template <int i>struct b_t<false,i>{};
template <>struct b_t<true,1>{
union{
float b;
DWORD i;
};
};
template <>struct b_t<true,2>{
union{
float b[2];
DWORD i[2];
};
};
template <>struct b_t<true,3>{
union{
float b[3];
DWORD i[3];
};
};
template <>struct b_t<true,4>{
union{
float b[4];
DWORD i[4];
};
};
template <>struct b_t<true,5>{
union{
float b[5];
DWORD i[5];
};
};
//--------------TEX-----------
#define TEXn(a) ((a&D3DFVF_TEXCOUNT_MASK)>>D3DFVF_TEXCOUNT_SHIFT)
#define _D3DFVF_TEXFMT(a,l) ((a>>(l*2+16))&3)
#define TEX_CORDn(a,l) ((_D3DFVF_TEXFMT(a,l)==D3DFVF_TEXTUREFORMAT1) ?1:((_D3DFVF_TEXFMT(a,l)==D3DFVF_TEXTUREFORMAT2) ?2:((_D3DFVF_TEXFMT(a,l)==D3DFVF_TEXTUREFORMAT3) ?3:4)))
#define DECL_TEXCORD_T(N) template <bool b,int n>struct texcord ## N ##_t;template <int n>struct texcord##N##_t<false,n>{};template <>struct texcord##N##_t<true,1>{float tu##N;};template <>struct texcord##N##_t<true,2>{float tu##N;float tv##N;};template <>struct texcord##N##_t<true,3>{float tu##N;float tv##N;float ta##N;};template <>struct texcord##N##_t<true,4>{float tu##N;float tv##N;float ta##N;float tb##N;};
DECL_TEXCORD_T(0)
DECL_TEXCORD_T(1)
DECL_TEXCORD_T(2)
DECL_TEXCORD_T(3)
DECL_TEXCORD_T(4)
DECL_TEXCORD_T(5)
DECL_TEXCORD_T(6)
DECL_TEXCORD_T(7)
template <const DWORD flag>
struct tex_t: public texcord0_t<(TEXn(flag)>0),TEX_CORDn(flag,0)>,
public texcord1_t<(TEXn(flag)>1),TEX_CORDn(flag,1)>,
public texcord2_t<(TEXn(flag)>2),TEX_CORDn(flag,2)>,
public texcord3_t<(TEXn(flag)>3),TEX_CORDn(flag,3)>,
public texcord4_t<(TEXn(flag)>4),TEX_CORDn(flag,4)>,
public texcord5_t<(TEXn(flag)>5),TEX_CORDn(flag,5)>,
public texcord6_t<(TEXn(flag)>6),TEX_CORDn(flag,6)>,
public texcord7_t<(TEXn(flag)>7),TEX_CORDn(flag,7)>
{
};
};//end of _D3DFvf
template <const DWORD Flags>
struct D3DFvf: public _D3DFvf::pos_t<TestMask(Flags,D3DFVF_POSITION_MASK)>,
public _D3DFvf::rhw_t<tp(Flags,D3DFVF_XYZRHW)>,
public _D3DFvf::w_t<tp(Flags,D3DFVF_XYZW)>,
public _D3DFvf::b_t<IsXYZBn(Flags),XYZBn(Flags)>,
public _D3DFvf::n_t<TestMask(Flags,D3DFVF_NORMAL)>,
public _D3DFvf::psize_t<TestMask(Flags,D3DFVF_PSIZE)>,
public _D3DFvf::diff_t<TestMask(Flags,D3DFVF_DIFFUSE)>,
public _D3DFvf::spec_t<TestMask(Flags,D3DFVF_SPECULAR)>,
public _D3DFvf::tex_t<Flags>
{
};
#undef TestFlag
#undef TestMask
#undef tp
#undef XYZBn
#undef IsXYZBn
#undef TEXn
#undef _D3DFVF_TEXFMT
#undef TEX_CORDn
#undef DECL_TEXCORD_T
#endif
