Libs/MaterialSystem/Common/OpenGLState.hpp

   1 /*
   2 Cafu Engine, http://www.cafu.de/
   3 Copyright (c) Carsten Fuchs and other contributors.
   4 This project is licensed under the terms of the MIT license.
   5 */
   6
   7 /********************/
   8 /*** OpenGL State ***/
   9 /********************/
  10
  11 #ifndef CAFU_MATSYS_OPENGLSTATE_HPP_INCLUDED
  12 #define CAFU_MATSYS_OPENGLSTATE_HPP_INCLUDED
  13
  14 // Required for #include <GL/gl.h> with MS VC++.
  15 #if defined(_WIN32) && defined(_MSC_VER)
  16 #define WIN32_LEAN_AND_MEAN
  17 #include <windows.h>
  18 #endif
  19
  20 #include <GL/gl.h>
  21
  22
  23 class DepRelMatrixT;
  24
  25
  26 /// This class encapsulates the OpenGL state, with the intention of minimizing actual OpenGL state changes.
  27 class OpenGLStateT
  28 {
  29     public:
  30
  31     void Reset();
  32
  33     void ActiveTextureUnit(GLenum texUnit);
  34     void AlphaFunc(GLenum func, GLclampf ref);
  35     void BlendFunc(GLenum sfactor, GLenum dfactor);
  36     void DepthFunc(GLenum func);
  37     void ActiveStencilFace(GLenum mode);
  38     void StencilFunc(GLenum func, GLint ref, GLuint mask);
  39     void StencilOp(GLenum fail, GLenum zfail, GLenum zpass);
  40     void ColorMask(GLboolean red, GLboolean green, GLboolean blue, GLboolean alpha);
  41     void DepthMask(GLboolean flag);
  42     void CullFace(GLenum mode);
  43     void FrontFace(GLenum mode);
  44     void PolygonMode(/*GLenum face=GL_FRONT_AND_BACK,*/ GLenum mode);
  45     void PolygonOffset(GLfloat factor, GLfloat units);
  46     void Enable(GLenum cap);
  47     void Disable(GLenum cap);
  48
  49
  50     // Matrix related functions.
  51     enum MatrixModeT { MODELVIEW, PROJECTION, TEXTURE, MATRIX0 };   // Simply use MATRIX0+i for more.
  52
  53     // Note that this method (in combination with DepRelMatrixTs) subsumes *all* OpenGL matrix functions!
  54     // (That is, there is *intentionally* no glMatrixMode(), glLoadIdentity(), glTranslate(), glRotate(), ...)
  55     void LoadMatrix(MatrixModeT MatrixMode, const DepRelMatrixT& Matrix);
  56
  57
  58     // Functions that only affect the current texture unit.
  59     void BindTexture(GLenum target, GLuint texture);
  60     void TexEnv(GLenum target, GLenum pname, GLint    param);
  61     void TexEnv(GLenum target, GLenum pname, GLfloat  param);
  62     void TexEnv(GLenum target, GLenum pname, GLint*   param);
  63     void TexEnv(GLenum target, GLenum pname, GLfloat* param);
  64  // void TexGen*();
  65  // void TexImage*();
  66  // void TexParameter*();
  67
  68
  69     static const GLenum MeshToOpenGLType[];             ///< Translates from MeshT primitive types to OpenGL rendering primitives.
  70     static const GLenum WindingToOpenGL[];              ///< Translates from MeshT windings to OpenGL windings (cw or ccw).
  71     static const GLenum BlendFactorToOpenGL[];          ///< Translates from MaterialT blend factors to OpenGL blend factors.
  72     static const GLenum PolygonModeToOpenGL[];          ///< Translates from MaterialT::PolygonModeT to OpenGL polygon modes.
  73     static const GLenum PolygonModeToOpenGL_Offset[];   ///< Translates from MaterialT::PolygonModeT to OpenGL depth offset polygon modes.
  74     static const GLenum MatrixModeToOpenGL[];           ///< Translates from our MatrixModeT modes to OpenGL matrix modes.
  75
  76     static OpenGLStateT* GetInstance();
  77
  78
  79     private:
  80
  81     struct TexUnitStateT
  82     {
  83         GLuint TexObj1D;
  84         GLuint TexObj2D;
  85         GLuint TexObj3D;
  86         GLuint TexObjCube;
  87
  88         // OpenGL permits to enable multiple texturing targets simultaneously, and uses in such cases the one with the highest dimensionality enabled.
  89         // See the "OpenGL Programming Guide (Red Book)", page 357 for details.
  90         // I change the semantic of calls to OpenGLStateT::Enable(GL_TEXTURE_*) such that only one target is ever enabled at any one time.
  91         bool   Texturing_IsEnabled;
  92         GLenum Texturing_Target;        ///< One of GL_TEXTURE_1D, GL_TEXTURE_2D, GL_TEXTURE_3D, GL_TEXTURE_CUBE_MAP_ARB.
  93
  94         bool   IsEnabled_TextureGenQ;
  95         bool   IsEnabled_TextureGenR;
  96         bool   IsEnabled_TextureGenS;
  97         bool   IsEnabled_TextureGenT;
  98     };
  99
 100     GLenum        ActiveTexUnit_Unit;
 101     unsigned long ActiveTexUnit_Index;
 102     GLenum        AlphaFunc_Func;
 103     GLclampf      AlphaFunc_Ref;
 104     GLenum        BlendFunc_sfactor;
 105     GLenum        BlendFunc_dfactor;
 106     GLenum        DepthFunc_Func;
 107     GLenum        ActiveStencilFace_Mode;
 108     GLenum        StencilFunc_Func[2];
 109     GLint         StencilFunc_ref[2];
 110     GLuint        StencilFunc_mask[2];
 111     GLenum        StencilOp_fail[2];
 112     GLenum        StencilOp_zfail[2];
 113     GLenum        StencilOp_zpass[2];
 114     GLboolean     ColorMask_FlagRed;
 115     GLboolean     ColorMask_FlagGreen;
 116     GLboolean     ColorMask_FlagBlue;
 117     GLboolean     ColorMask_FlagAlpha;
 118     GLboolean     DepthMask_Flag;
 119     GLenum        CullFace_mode;
 120     GLenum        FrontFace_mode;
 121     GLenum        PolygonMode_mode;
 122     GLfloat       PolygonOffset_factor;
 123     GLfloat       PolygonOffset_units;
 124     bool          IsEnabled_AlphaTest;
 125     bool          IsEnabled_AutoNormal;
 126     bool          IsEnabled_Blend;
 127  // bool          IsEnabled_ClipPlanei;
 128     bool          IsEnabled_ColorMaterial;
 129     bool          IsEnabled_CullFace;
 130     bool          IsEnabled_DepthTest;
 131     bool          IsEnabled_Dither;
 132     bool          IsEnabled_Fog;
 133  // bool          IsEnabled_Lighti;
 134     bool          IsEnabled_Lighting;
 135     bool          IsEnabled_LineSmooth;
 136     bool          IsEnabled_LineStipple;
 137     bool          IsEnabled_LogicOp;
 138     bool          IsEnabled_Normalize;
 139     bool          IsEnabled_PointSmooth;
 140     bool          IsEnabled_PolygonSmooth;
 141     bool          IsEnabled_PolygonStipple;
 142     bool          IsEnabled_PolygonOffsetFill;
 143     bool          IsEnabled_PolygonOffsetLine;
 144     bool          IsEnabled_PolygonOffsetPoint;
 145     bool          IsEnabled_ScissorTest;
 146     bool          IsEnabled_StencilTest;
 147     bool          IsEnabled_StencilTestTwoSide;
 148     unsigned long LoadedMatrixID [3+32];    ///< MatrixID[MM] stores the ID  of the DepRelMatrixT that is bound to (loaded at) the corresponding OpenGL matrix mode.
 149     unsigned long LoadedMatrixAge[3+32];    ///< MatrixID[MM] stores the age of the DepRelMatrixT that is bound to (loaded at) the corresponding OpenGL matrix mode.
 150     TexUnitStateT TexUnitStates[8];
 151
 152     /// The constructor. Private because this is a singleton class.
 153     OpenGLStateT();
 154 };
 155
 156 #endif