openmw/components/nif/property.hpp

/*
  OpenMW - The completely unofficial reimplementation of Morrowind
  Copyright (C) 2008-2010  Nicolay Korslund
  Email: < korslund@gmail.com >
  WWW: http://openmw.sourceforge.net/

  This file (property.h) is part of the OpenMW package.

  OpenMW is distributed as free software: you can redistribute it
  and/or modify it under the terms of the GNU General Public License
  version 3, as published by the Free Software Foundation.

  This program is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  version 3 along with this program. If not, see
  http://www.gnu.org/licenses/ .

 */

#ifndef _NIF_PROPERTY_H_
#define _NIF_PROPERTY_H_

#include "controlled.hpp"

namespace Nif
{

class Property : public Named
{
public:
  // The meaning of these depends on the actual property type.
  int flags;

  void read(NIFFile *nif)
  {
    Named::read(nif);
    flags = nif->getShort();
  }
};

class NiTexturingProperty : public Property
{
public:
  // A sub-texture
  struct Texture
  {
    /* Clamp mode
       0 - clampS clampT
       1 - clampS wrapT
       2 - wrapS clampT
       3 - wrapS wrapT
    */

    /* Filter:
       0 - nearest
       1 - bilinear
       2 - trilinear
       3, 4, 5 - who knows
    */
    bool inUse;
    NiSourceTexturePtr texture;

    int clamp, set, filter;
    short unknown2;

    void read(NIFFile *nif)
    {
      inUse = !!nif->getInt();
      if(!inUse) return;

      texture.read(nif);
      clamp = nif->getInt();
      filter = nif->getInt();
      set = nif->getInt();

      // I have no idea, but I think these are actually two
      // PS2-specific shorts (ps2L and ps2K), followed by an unknown
      // short.
      nif->skip(6);
    }
  };

  /* Apply mode:
     0 - replace
     1 - decal
     2 - modulate
     3 - hilight  // These two are for PS2 only?
     4 - hilight2
  */
  int apply;

  /*
   * The textures in this list are as follows:
   *
   * 0 - Base texture
   * 1 - Dark texture
   * 2 - Detail texture
   * 3 - Gloss texture (never used?)
   * 4 - Glow texture
   * 5 - Bump map texture
   * 6 - Decal texture
   */
  Texture textures[7];

  void read(NIFFile *nif)
  {
    Property::read(nif);
    apply = nif->getInt();

    // Unknown, always 7. Probably the number of textures to read
    // below
    nif->getInt();

    textures[0].read(nif); // Base
    textures[1].read(nif); // Dark
    textures[2].read(nif); // Detail
    textures[3].read(nif); // Gloss (never present)
    textures[4].read(nif); // Glow
    textures[5].read(nif); // Bump map
    if(textures[5].inUse)
      {
        // Ignore these at the moment
        /*float lumaScale =*/ nif->getFloat();
        /*float lumaOffset =*/ nif->getFloat();
        /*const Vector4 *lumaMatrix =*/ nif->getVector4();
      }
    textures[6].read(nif); // Decal
  }
};

// These contain no other data than the 'flags' field in Property
typedef Property NiShadeProperty;
typedef Property NiDitherProperty;
typedef Property NiZBufferProperty;
typedef Property NiSpecularProperty;
typedef Property NiWireframeProperty;

// The rest are all struct-based
template <typename Struct>
struct StructPropT : Property
{
  const Struct* data;

  void read(NIFFile *nif)
  {
    Property::read(nif);
    data = nif->getPtr<Struct>();
  }
};

struct S_MaterialProperty
{
  // The vector components are R,G,B
  Vector ambient, diffuse, specular, emissive;
  float glossiness, alpha;
};

struct S_VertexColorProperty
{
  /* Vertex mode:
     0 - source ignore
     1 - source emmisive
     2 - source amb diff

     Lighting mode
     0 - lighting emmisive
     1 - lighting emmisive ambient/diffuse
  */
  int vertmode, lightmode;
};

struct S_AlphaProperty
{
  /*
    In NiAlphaProperty, the flags have the following meaning:

    Bit 0 : alpha blending enable
    Bits 1-4 : source blend mode
    Bits 5-8 : destination blend mode
    Bit 9 : alpha test enable
    Bit 10-12 : alpha test mode
    Bit 13 : no sorter flag ( disables triangle sorting )

    blend modes (glBlendFunc):
    0000 GL_ONE
    0001 GL_ZERO
    0010 GL_SRC_COLOR
    0011 GL_ONE_MINUS_SRC_COLOR
    0100 GL_DST_COLOR
    0101 GL_ONE_MINUS_DST_COLOR
    0110 GL_SRC_ALPHA
    0111 GL_ONE_MINUS_SRC_ALPHA
    1000 GL_DST_ALPHA
    1001 GL_ONE_MINUS_DST_ALPHA
    1010 GL_SRC_ALPHA_SATURATE

    test modes (glAlphaFunc):
    000 GL_ALWAYS
    001 GL_LESS
    010 GL_EQUAL
    011 GL_LEQUAL
    100 GL_GREATER
    101 GL_NOTEQUAL
    110 GL_GEQUAL
    111 GL_NEVER

    Taken from:
    http://niftools.sourceforge.net/doc/nif/NiAlphaProperty.html

    Right now we only use standard alpha blending (see the Ogre code
    that sets it up) and it appears that this is the only blending
    used in the original game. Bloodmoon (along with several mods) do
    however use other settings, such as discarding pixel values with
    alpha < 1.0. This is faster because we don't have to mess with the
    depth stuff like we did for blending. And OGRE has settings for
    this too.
  */

  // Tested against when certain flags are set (see above.)
  unsigned char threshold;
};

typedef StructPropT<S_AlphaProperty> NiAlphaProperty;
typedef StructPropT<S_MaterialProperty> NiMaterialProperty;
typedef StructPropT<S_VertexColorProperty> NiVertexColorProperty;

} // Namespace
#endif