d3d9_reflect.cpp

D3D9 reflection data reading

// NOTE: We parse the constant table by hand since shadergen has to link against the
// Xenon (XBox 360) d3dx lib statically if Xbox builds are to be supported. That means
// we can't easily use non-Xenon D3DX from here.

// **** This part copy & pasted from D3DX headers (but it's a file format so it's consistent
// across versions)

//----------------------------------------------------------------------------
// D3DXSHADER_CONSTANTTABLE:
// -------------------------
// Shader constant information; included as an CTAB comment block inside
// shaders.  All offsets are BYTE offsets from start of CONSTANTTABLE struct.
// Entries in the table are sorted by Name in ascending order.
//----------------------------------------------------------------------------

typedef struct _D3DXSHADER_CONSTANTTABLE
{
    DWORD Size;             // sizeof(D3DXSHADER_CONSTANTTABLE)
    DWORD Creator;          // LPCSTR offset
    DWORD Version;          // shader version
    DWORD Constants;        // number of constants
    DWORD ConstantInfo;     // D3DXSHADER_CONSTANTINFO[Constants] offset
    DWORD Flags;            // flags shader was compiled with
    DWORD Target;           // LPCSTR offset 

} D3DXSHADER_CONSTANTTABLE, *LPD3DXSHADER_CONSTANTTABLE;


typedef struct _D3DXSHADER_CONSTANTINFO
{
    DWORD Name;             // LPCSTR offset
    WORD  RegisterSet;      // D3DXREGISTER_SET
    WORD  RegisterIndex;    // register number
    WORD  RegisterCount;    // number of registers
    WORD  Reserved;         // reserved
    DWORD TypeInfo;         // D3DXSHADER_TYPEINFO offset
    DWORD DefaultValue;     // offset of default value

} D3DXSHADER_CONSTANTINFO, *LPD3DXSHADER_CONSTANTINFO;


typedef struct _D3DXSHADER_TYPEINFO
{
    WORD  Class;            // D3DXPARAMETER_CLASS
    WORD  Type;             // D3DXPARAMETER_TYPE
    WORD  Rows;             // number of rows (matrices)
    WORD  Columns;          // number of columns (vectors and matrices)
    WORD  Elements;         // array dimension
    WORD  StructMembers;    // number of struct members
    DWORD StructMemberInfo; // D3DXSHADER_STRUCTMEMBERINFO[Members] offset

} D3DXSHADER_TYPEINFO, *LPD3DXSHADER_TYPEINFO;


typedef struct _D3DXSHADER_STRUCTMEMBERINFO
{
    DWORD Name;             // LPCSTR offset
    DWORD TypeInfo;         // D3DXSHADER_TYPEINFO offset

} D3DXSHADER_STRUCTMEMBERINFO, *LPD3DXSHADER_STRUCTMEMBERINFO;

// **** End of copy & pasted part

// ...

if (blob) {
   DWORD *data = (DWORD *) blob->GetBufferPointer();

   if (memcmp(data + 2, "CTAB", 4) != 0)
      codegen_error("Constant table not found!");

   BYTE *ctbase = (BYTE *) (data + 3);
   D3DXSHADER_CONSTANTTABLE *ctab = (D3DXSHADER_CONSTANTTABLE *) ctbase;
   D3DXSHADER_CONSTANTINFO *c = (D3DXSHADER_CONSTANTINFO *) (ctbase + ctab->ConstantInfo);

   for (int j=0; j < sbcount(family->vars); j++) {
     int k, ind = -1;

     // find offset of constant
     for (k=0; k < (int) ctab->Constants; k++)
        if(strcmp(family->vars[j], (char *) (ctbase + c[k].Name)) == 0)
           ind = c[k].RegisterIndex;

     // use ind
   }
}