The Utilities Experience/The Utilities Experience - Volume 1.iso/software/misc/o-z/x-windows/mesa-amiwin/src/context.h

C/C++ Source or Header | 1995-11-30 | 21.9 KB | 765 lines

/* context.h */

/*
 * Mesa 3-D graphics library
 * Version:  1.2
 * Copyright (C) 1995  Brian Paul  ([e-mail])
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */


/*
$Id: context.h,v 1.37 1995/11/22 13:34:49 brianp Exp $

$Log: context.h,v $
 * Revision 1.37  1995/11/22  13:34:49  brianp
 * added MutableColors flag
 *
 * Revision 1.36  1995/11/13  21:28:24  brianp
 * added comment about TextureWidth/Height
 *
 * Revision 1.35  1995/11/02  14:57:14  brianp
 * changed LastEnabled to GLint type
 *
 * Revision 1.34  1995/11/01  21:44:15  brianp
 * added CC.Light.LastEnabled
 *
 * Revision 1.33  1995/10/27  20:28:27  brianp
 * added glPolygonOffsetEXT() support
 *
 * Revision 1.32  1995/10/19  15:45:38  brianp
 * added gamma support
 * new arguments to gl_new_context()
 *
 * Revision 1.31  1995/10/17  21:34:03  brianp
 * added typedefs for points_func, line_func, and polygon_func
 *
 * Revision 1.30  1995/10/14  16:26:13  brianp
 * enable dithering by default
 * added SWmasking code
 *
 * Revision 1.29  1995/09/25  16:31:29  brianp
 * reorganized front and back material indexing
 *
 * Revision 1.28  1995/09/15  18:48:52  brianp
 * introduced CC.NewState convention
 * cleaned up comments, removed dead code
 *
 * Revision 1.27  1995/08/01  22:36:12  brianp
 * fixed an extension-compatibility symbol problem
 *
 * Revision 1.26  1995/08/01  22:23:04  brianp
 * added definitions for extension symbols when using non-Mesa header files
 *
 * Revision 1.25  1995/07/25  16:41:54  brianp
 * made changes for using CC.VertexFunc pointer
 *
 * Revision 1.24  1995/07/17  22:32:31  brianp
 * added ClipSpans flag to handle viewports which extend beyond the window
 *
 * Revision 1.23  1995/06/05  20:26:24  brianp
 * added Unfilled field to gl_polygon struct
 *
 * Revision 1.22  1995/05/31  14:32:37  brianp
 * changed BufferWidth, BufferHeight to GLint
 *
 * Revision 1.21  1995/05/22  20:59:34  brianp
 * Release 1.2
 *
 * Revision 1.20  1995/05/17  13:52:37  brianp
 * implemented glIndexMask(0) and glColorMask(0,0,0,0)
 *
 * Revision 1.19  1995/05/17  13:17:22  brianp
 * changed default CC.Mode value to allow use of real OpenGL headers
 * removed need for CC.MajorMode variable
 *
 * Revision 1.18  1995/05/15  16:06:28  brianp
 * implemented shared/nonshared display lists
 *
 * Revision 1.17  1995/05/12  16:30:14  brianp
 * Texture images stored as bytes, not floats
 *
 * Revision 1.16  1995/04/17  13:51:19  brianp
 * added gl_copy_context() function
 *
 * Revision 1.15  1995/04/11  14:04:05  brianp
 * moved CC.write... functions to dd
 *
 * Revision 1.14  1995/03/30  21:08:04  brianp
 * updated to use pointers to CC.write_* functions
 *
 * Revision 1.13  1995/03/27  20:31:26  brianp
 * new Texture.Enabled scheme
 *
 * Revision 1.12  1995/03/24  16:59:41  brianp
 * added gl_update_pixel_logic
 *
 * Revision 1.11  1995/03/24  15:30:10  brianp
 * cleaned up CC struct and removed vertex buffer arrays
 *
 * Revision 1.10  1995/03/22  21:37:22  brianp
 * removed BufferDepth from CC
 *
 * Revision 1.9  1995/03/10  16:26:43  brianp
 * updated for bleding extensions
 *
 * Revision 1.8  1995/03/09  21:39:51  brianp
 * added ModelViewInvValid flag
 *
 * Revision 1.7  1995/03/08  15:10:02  brianp
 * added support for dd_logicop
 *
 * Revision 1.6  1995/03/07  14:20:28  brianp
 * removed ClearColorInt field
 *
 * Revision 1.5  1995/03/04  19:25:29  brianp
 * 1.1 beta revision
 *
 * Revision 1.4  1995/03/02  19:17:02  brianp
 * new RasterMask logic, fixed some comments
 *
 * Revision 1.3  1995/02/27  22:48:33  brianp
 * modified for PB
 *
 * Revision 1.2  1995/02/27  15:07:32  brianp
 * added Vcolor/Vindex scheme
 *
 * Revision 1.1  1995/02/24  14:18:47  brianp
 * Initial revision
 *
 */


#ifndef CONTEXT_H
#define CONTEXT_H


#include "GL/gl.h"
#include "config.h"


struct gl_light {
    GLfloat Ambient[4];        /* ambient color */
    GLfloat Diffuse[4];        /* diffuse color */
    GLfloat Specular[4];        /* specular color */
    GLfloat Position[4];        /* position in eye coordinates */
    GLfloat NormPosition[3];    /* unit vector from origin to pos */
    GLfloat Direction[4];        /* spotlight dir in eye coordinates */
    GLfloat SpotExponent;
    GLfloat SpotCutoff;        /* in degress */
    GLfloat ConstantAttenuation;
    GLfloat LinearAttenuation;
    GLfloat QuadraticAttenuation;
    GLboolean Enabled;        /* On/off flag */
};


struct gl_lightmodel {
    GLfloat Ambient[4];        /* ambient color */
    GLboolean LocalViewer;        /* Local (or infinite) view point? */
    GLboolean TwoSide;        /* Two (or one) sided lighting? */
};


struct gl_material {
    GLfloat Ambient[4];
    GLfloat Diffuse[4];
    GLfloat Specular[4];
    GLfloat Emission[4];
    GLfloat Shininess;
    GLfloat AmbientIndex;    /* for color index lighting */
    GLfloat DiffuseIndex;    /* for color index lighting */
    GLfloat SpecularIndex;    /* for color index lighting */
};



/*
 * Attribute structures:
 *    We define a struct for each attribute group to make pushing and
 *    popping attributes easy.  Also it's a good organization.
 */


struct gl_accum_attrib {
    GLfloat ClearColor[4];    /* Accumulation buffer clear color */
};


struct gl_colorbuffer_attrib {
    GLuint ClearIndex;        /* Index to use for glClear */
    GLfloat ClearColor[4];        /* Color to use for glClear */

    GLuint IndexMask;        /* Color index write mask */
    GLuint ColorMask;        /* bit 3=red,2=green,1=blue,0=alpha*/
        GLboolean SWmasking;        /* Do color/CI masking in software? */

    GLenum DrawBuffer;        /* Which buffer to draw into */

    /* alpha testing */
    GLboolean AlphaEnabled;        /* Alpha test enabled flag */
    GLenum AlphaFunc;        /* Alpha test function */
    GLfloat AlphaRef;        /* Alpha reference value */
    GLint AlphaRefInt;        /* AlphaRef scaled to an integer */

    /* blending */
    GLboolean BlendEnabled;        /* Blending enabled flag */
    GLenum BlendSrc;        /* Blending source operator */
    GLenum BlendDst;        /* Blending destination operator */
    GLenum BlendEquation;        /* BlendEquation EXTENSION */
    GLfloat BlendColor[4];        /* BlendColor EXTENSION */

    /* logic op */
    GLboolean LogicOpEnabled;    /* Logic op enabled flag */
    GLboolean SWLogicOpEnabled;    /* Do logic ops in software? */
    GLenum LogicOp;            /* Logic operator */

    GLboolean DitherFlag;        /* Dither enable flag */
};


struct gl_current_attrib {
    GLfloat Color[4];        /* Current RGBA color */
    GLuint Index;            /* Current color index */
    GLfloat Normal[3];        /* Current normal vector */
    GLfloat TexCoord[4];        /* Current texture coordinate */
    GLfloat RasterPos[4];        /* Current raster position */
    GLfloat RasterDistance;        /* Current raster distance */
    GLfloat RasterColor[4];        /* Current raster color */
    GLuint RasterIndex;        /* Current raster index */
    GLfloat RasterTexCoord[4];    /* Current raster texture coord */
    GLboolean RasterPosValid;    /* Raster position valid flag */
    GLboolean EdgeFlag;        /* Current edge flag */
};


struct gl_depthbuffer_attrib {
    GLenum Func;        /* Function for depth buffer compare */
    GLfloat Clear;        /* Value to clear depth buffer to */
    GLboolean Test;        /* Depth buffering enabled flag */
    GLboolean Mask;        /* Depth buffer writable? */
};


struct gl_enable_attrib {
    GLboolean AlphaTest;
    GLboolean AutoNormal;
    GLboolean Blend;
    GLboolean ClipPlane[MAX_CLIP_PLANES];
    GLboolean ColorMaterial;
    GLboolean CullFace;
    GLboolean DepthTest;
    GLboolean Dither;
    GLboolean Fog;
    GLboolean Light[MAX_LIGHTS];
    GLboolean Lighting;
    GLboolean LineSmooth;
    GLboolean LineStipple;
    GLboolean LogicOp;
    GLboolean Map1Color4;
    GLboolean Map1Index;
    GLboolean Map1Normal;
    GLboolean Map1TextureCoord1;
    GLboolean Map1TextureCoord2;
    GLboolean Map1TextureCoord3;
    GLboolean Map1TextureCoord4;
    GLboolean Map1Vertex3;
    GLboolean Map1Vertex4;
    GLboolean Map2Color4;
    GLboolean Map2Index;
    GLboolean Map2Normal;
    GLboolean Map2TextureCoord1;
    GLboolean Map2TextureCoord2;
    GLboolean Map2TextureCoord3;
    GLboolean Map2TextureCoord4;
    GLboolean Map2Vertex3;
    GLboolean Map2Vertex4;
    GLboolean Normalize;
    GLboolean PointSmooth;
    GLboolean PolygonOffset;
    GLboolean PolygonSmooth;
    GLboolean PolygonStipple;
    GLboolean Scissor;
    GLboolean Stencil;
    GLuint Texture;
    GLuint TexGen;
};


struct gl_eval_attrib {
    /* Enable bits */
    GLboolean Map1Color4;
    GLboolean Map1Index;
    GLboolean Map1Normal;
    GLboolean Map1TextureCoord1;
    GLboolean Map1TextureCoord2;
    GLboolean Map1TextureCoord3;
    GLboolean Map1TextureCoord4;
    GLboolean Map1Vertex3;
    GLboolean Map1Vertex4;
    GLboolean Map2Color4;
    GLboolean Map2Index;
    GLboolean Map2Normal;
    GLboolean Map2TextureCoord1;
    GLboolean Map2TextureCoord2;
    GLboolean Map2TextureCoord3;
    GLboolean Map2TextureCoord4;
    GLboolean Map2Vertex3;
    GLboolean Map2Vertex4;
    GLboolean AutoNormal;
    /* Map Grid endpoints and divisions */
    GLuint MapGrid1un;
    GLfloat MapGrid1u1, MapGrid1u2;
    GLuint MapGrid2un, MapGrid2vn;
    GLfloat MapGrid2u1, MapGrid2u2;
    GLfloat MapGrid2v1, MapGrid2v2;
};


struct gl_fog_attrib {
    GLboolean Enabled;        /* Fog enabled flag */
    GLfloat Color[4];        /* Fog color */
    GLfloat Density;        /* Density >= 0.0 */
    GLfloat Start;            /* Start distance in eye coords */
    GLfloat End;            /* End distance in eye coords */
    GLfloat Index;            /* Fog index */
    GLenum Mode;            /* Fog mode */
};


struct gl_hint_attrib {
    /* always one of GL_FASTEST, GL_NICEST, or GL_DONT_CARE */
    GLenum PerspectiveCorrection;
    GLenum PointSmooth;
    GLenum LineSmooth;
    GLenum PolygonSmooth;
    GLenum Fog;
};


struct gl_light_attrib {
    struct gl_light Light[MAX_LIGHTS];    /* Array of lights */
    struct gl_lightmodel Model;        /* Lighting model */
    struct gl_material Material[2];        /* Material 0=front, 1=back */
    GLboolean Enabled;            /* Lighting enabled flag */
    GLenum ShadeModel;            /* GL_FLAT or GL_SMOOTH */
    GLenum ColorMaterialFace;        /* see glColorMaterial */
    GLenum ColorMaterialMode;        /* see glColorMaterial */
    GLboolean ColorMaterialEnabled;        /* see glColorMaterial */
        GLint LastEnabled;            /* a lighting optimization */
};


struct gl_line_attrib {
    GLboolean SmoothFlag;        /* GL_LINE_SMOOTH enabled? */
    GLboolean StippleFlag;        /* GL_LINE_STIPPLE enabled? */
    GLushort StipplePattern;    /* Stipple pattern */
    GLint StippleFactor;        /* Stipple repeat factor */
    GLfloat Width;            /* Line width */
};


struct gl_list_attrib {
    GLuint ListBase;
};


struct gl_pixel_attrib {
    GLenum ReadBuffer;
    GLfloat RedBias, RedScale;    /* Pixel xfer bias & scale values */
    GLfloat GreenBias, GreenScale;
    GLfloat BlueBias, BlueScale;
    GLfloat AlphaBias, AlphaScale;
    GLfloat DepthBias, DepthScale;
    GLint IndexShift;
    GLint IndexOffset;
    GLboolean MapColorFlag;
    GLboolean MapStencilFlag;
    GLfloat ZoomX;            /* Pixel zoom X factor */
    GLfloat ZoomY;            /* Pixel zoom Y factor */
    /* TODO: Do the following belong here??? */
    GLint MapStoSsize;            /* Size of each pixel map */
    GLint MapItoIsize;
    GLint MapItoRsize;
    GLint MapItoGsize;
    GLint MapItoBsize;
    GLint MapItoAsize;
    GLint MapRtoRsize;
    GLint MapGtoGsize;
    GLint MapBtoBsize;
    GLint MapAtoAsize;
    GLint MapStoS[MAX_PIXEL_MAP_TABLE];    /* Pixel map tables */
    GLint MapItoI[MAX_PIXEL_MAP_TABLE];
    GLfloat MapItoR[MAX_PIXEL_MAP_TABLE];
    GLfloat MapItoG[MAX_PIXEL_MAP_TABLE];
    GLfloat MapItoB[MAX_PIXEL_MAP_TABLE];
    GLfloat MapItoA[MAX_PIXEL_MAP_TABLE];
    GLfloat MapRtoR[MAX_PIXEL_MAP_TABLE];
    GLfloat MapGtoG[MAX_PIXEL_MAP_TABLE];
    GLfloat MapBtoB[MAX_PIXEL_MAP_TABLE];
    GLfloat MapAtoA[MAX_PIXEL_MAP_TABLE];
};


struct gl_point_attrib {
    GLboolean SmoothFlag;    /* True if GL_POINT_SMOOTH is enabled */
    GLfloat Size;        /* Point size */
};


struct gl_polygon_attrib {
    GLenum FrontFace;    /* Either GL_CW or GL_CCW */
    GLenum FrontMode;    /* Either GL_POINT, GL_LINE or GL_FILL */
    GLenum BackMode;    /* Either GL_POINT, GL_LINE or GL_FILL */
    GLboolean Unfilled;    /* True if back or front mode is not GL_FILL */
    GLenum CullFaceMode;    /* Culling mode GL_FRONT or GL_BACK */
    GLboolean CullFlag;    /* Culling on/off flag */
    GLboolean SmoothFlag;    /* True if GL_POLYGON_SMOOTH is enabled */
    GLboolean StippleFlag;    /* True if GL_POLYGON_STIPPLE is enabled */
        GLfloat OffsetFactor;   /* Polygon offset factor */
        GLfloat OffsetBias;     /* Polygon offset bias */
        GLboolean OffsetEnabled;/* Polygon offset enable */
};


struct gl_scissor_attrib {
    GLboolean    Enabled;        /* Scissor test enabled? */
    GLint        X, Y;            /* Lower left corner of box */
    GLsizei        Width, Height;        /* Size of box */
    GLint        Xmin, Xmax, Ymin, Ymax;    /* Bounds in window coords */
};


struct gl_stencil_attrib {
    GLboolean    Enabled;    /* Enabled flag */
    GLenum        Function;    /* Stencil function */
    GLint        Ref;        /* Reference value */
    GLuint        ValueMask;    /* Value mask */
    GLenum        FailFunc;    /* Fail function */
    GLenum        ZPassFunc;    /* Depth buffer pass function */
    GLenum        ZFailFunc;    /* Depth buffer fail function */
    GLuint        Clear;        /* Clear value */
    GLuint        WriteMask;    /* Write mask */
};


#define Q_BIT 1
#define R_BIT 2
#define S_BIT 4
#define T_BIT 8


struct gl_texture_attrib {
    GLuint Enabled;            /* Bitwise-OR of 1 and 2 */
    GLenum EnvMode;            /* GL_MODULATE, GL_DECAL, GL_BLEND */
    GLfloat EnvColor[4];
    GLfloat BorderColor[4];        /* TODO: border color 1-D and 2-D */
    GLuint TexGenEnabled;        /* Bitwise-OR of [QRST]_BIT values */
    GLenum GenModeS;        /* Tex coord generation mode, either */
    GLenum GenModeT;        /*    GL_OBJECT_LINEAR, or */
    GLenum GenModeR;        /*    GL_EYE_LINEAR, or    */
    GLenum GenModeQ;        /*      GL_SPHERE_MAP        */
    GLfloat ObjectPlaneS[4];
    GLfloat ObjectPlaneT[4];
    GLfloat ObjectPlaneR[4];
    GLfloat ObjectPlaneQ[4];
    GLfloat EyePlaneS[4];
    GLfloat EyePlaneT[4];
    GLfloat EyePlaneR[4];
    GLfloat EyePlaneQ[4];
    GLenum WrapS1D;            /* GL_CLAMP or GL_REPEAT */
    GLenum WrapT1D;            /* GL_CLAMP or GL_REPEAT */
    GLenum WrapS2D;            /* GL_CLAMP or GL_REPEAT */
    GLenum WrapT2D;            /* GL_CLAMP or GL_REPEAT */
    GLenum MinFilter1D;        /* 1-D minification filter */
    GLenum MagFilter1D;        /* 1-D magnification filter */
    GLenum MinFilter2D;        /* 2-D minification filter */
    GLenum MagFilter2D;        /* 2-D magnification filter */
};


struct gl_transform_attrib {
    GLenum MatrixMode;            /* Matrix mode */
    GLboolean Normalize;            /* Normalize all normals? */
    GLfloat ClipEquation[MAX_CLIP_PLANES][4];
    GLboolean ClipEnabled[MAX_CLIP_PLANES];
    GLboolean AnyClip;            /* Any ClipEnabled[] true? */

};


struct gl_viewport_attrib {
    GLint X, Y;        /* position */
    GLsizei Width, Height;    /* size */
    GLfloat Near, Far;    /* Depth buffer range */
    GLfloat Sx, Sy, Sz;    /* NDC to WinCoord scaling */
    GLfloat Tx, Ty, Tz;    /* NDC to WinCoord translation */
};


/* For the attribute stack: */
struct gl_attrib_node {
    GLbitfield kind;
    void *data;
    struct gl_attrib_node *next;
};


/* Display list info shared by multiple contexts: */
struct gl_list_group {
    union node *List[MAX_DISPLAYLISTS];    /* The display lists */
    GLboolean Reserved[MAX_DISPLAYLISTS];    /* Allocation flags */
    GLint RefCount;                /* Reference count */
};




/*
 * Bitmasks to indicate what auxillary information must be interpolated
 * when clipping (CC.ClipMask).
 */
#define CLIP_FCOLOR_BIT        0x01
#define CLIP_BCOLOR_BIT        0x02
#define CLIP_FINDEX_BIT        0x04
#define CLIP_BINDEX_BIT        0x08
#define CLIP_TEXTURE_BIT    0x10



/*
 * Bitmasks to indicate which rasterization options are enabled (CC.RasterMask)
 */
#define ALPHA_BIT        0x01
#define BLEND_BIT        0x02
#define DEPTH_BIT        0x04
#define FOG_BIT            0x08
#define LOGIC_OP_BIT        0x10
#define SCISSOR_BIT        0x20
#define STENCIL_BIT        0x40
#define MASKING_BIT        0x80
#define GAMMA_BIT               0x100

#define RASTER_BITS        0x1ff


typedef void (*points_func)( GLuint first, GLuint last );
typedef void (*line_func)( GLuint v1, GLuint v2, GLuint pv );
typedef void (*polygon_func)( GLuint n, GLuint vlist[], GLuint pv );



/*
 * The library context:
 */

struct gl_context {
    /* Modelview matrix and stack */
    GLfloat ModelViewMatrix[16];
    GLfloat ModelViewInv[16];    /* Inverse of ModelViewMatrix */
    GLboolean ModelViewInvValid;    /* Is the inverse matrix now valid? */
    GLuint ModelViewStackDepth;
    GLfloat ModelViewStack[MAX_MODELVIEW_STACK_DEPTH][16];

    /* Projection matrix and stack */
    GLfloat ProjectionMatrix[16];
    GLuint ProjectionStackDepth;
    GLfloat ProjectionStack[MAX_PROJECTION_STACK_DEPTH][16];

    /* Texture matrix and stack */
    GLfloat TextureMatrix[16];
        GLboolean IdentityTexMat;    /* Is TextureMatrix==Identity? */
    GLuint TextureStackDepth;
    GLfloat TextureStack[MAX_TEXTURE_STACK_DEPTH][16];

    /* Display List stuff */
    GLuint CallDepth;    /* Current recursion calling depth */
    GLboolean ExecuteFlag;    /* Execute GL commands? */
    GLboolean CompileFlag;    /* Compile GL commands into display list? */
    struct gl_list_group *ListGroup;    /* Shared display list group */

    /* Attribute stack */
    GLuint AttribStackDepth;
    struct gl_attrib_node *AttribStack[MAX_ATTRIB_STACK_DEPTH];

    /* Attribute groups */
    struct gl_accum_attrib        Accum;
    struct gl_colorbuffer_attrib    Color;
    struct gl_current_attrib    Current;
    struct gl_depthbuffer_attrib    Depth;
    struct gl_eval_attrib        Eval;
    struct gl_fog_attrib        Fog;
    struct gl_hint_attrib        Hint;
    struct gl_light_attrib        Light;
    struct gl_line_attrib        Line;
    struct gl_list_attrib        List;
    struct gl_pixel_attrib        Pixel;
    struct gl_point_attrib        Point;
    struct gl_polygon_attrib    Polygon;
    GLuint PolygonStipple[32];
    struct gl_scissor_attrib    Scissor;
    struct gl_stencil_attrib    Stencil;
    struct gl_texture_attrib    Texture;
    struct gl_transform_attrib    Transform;
    struct gl_viewport_attrib    Viewport;

    /* PixelStore parameters */
    GLint PackAlignment;
    GLint PackRowLength;
    GLint PackSkipPixels;
    GLint PackSkipRows;
    GLboolean PackSwapBytes;
    GLboolean PackLSBFirst;
    GLint UnpackAlignment;
    GLint UnpackRowLength;
    GLint UnpackSkipPixels;
    GLint UnpackSkipRows;
    GLboolean UnpackSwapBytes;
    GLboolean UnpackLSBFirst;

    /* Feedback */
    GLenum FeedbackType;
    GLuint FeedbackMask;
    GLfloat *FeedbackBuffer;
    GLuint FeedbackBufferSize;
    GLuint FeedbackCount;

    /* Selection */
    GLuint *SelectBuffer;
    GLuint SelectBufferSize;    /* size of SelectBuffer */
    GLuint SelectBufferCount;    /* number of values in SelectBuffer */
    GLuint SelectHits;        /* number of records in SelectBuffer */
    GLuint NameStackDepth;
    GLuint NameStack[MAX_NAME_STACK_DEPTH];
    GLboolean HitFlag;
    GLfloat HitMinZ, HitMaxZ;

    /* Current 1-D texture map */
    GLuint TextureComponents1D[MAX_TEXTURE_LEVELS];
    GLuint TextureWidth1D[MAX_TEXTURE_LEVELS];  /* includes border */
    GLuint TextureBorder1D[MAX_TEXTURE_LEVELS];
    GLubyte *TextureImage1D[MAX_TEXTURE_LEVELS];
    GLboolean TextureImage1DDeleteFlag[MAX_TEXTURE_LEVELS];

    /* Current 2-D texture map */
    GLuint TextureComponents2D[MAX_TEXTURE_LEVELS];
    GLuint TextureWidth2D[MAX_TEXTURE_LEVELS];  /* includes border */
    GLuint TextureHeight2D[MAX_TEXTURE_LEVELS]; /* includes border */
    GLuint TextureBorder2D[MAX_TEXTURE_LEVELS];
    GLubyte *TextureImage2D[MAX_TEXTURE_LEVELS];
    GLboolean TextureImage2DDeleteFlag[MAX_TEXTURE_LEVELS];

    /* Miscellaneous */
        GLboolean NewState;     /* If GL_TRUE, must call gl_update_state() */
    GLenum RenderMode;    /* either GL_RENDER, GL_SELECT, GL_FEEDBACK */
    GLenum Mode;        /* glBegin primitive or GL_BITMAP */

    GLuint StippleCounter;    /* Line stipple counter */
    GLuint ClipMask;    /* OR of CLIP_* values from above */
    GLuint RasterMask;    /* OR of rasterization flags */
    GLuint LightTwoSide;    /* Compute two-sided lighting? */
    GLboolean ComputePlane;    /* Compute plane eq. for polygons? */
    GLfloat PlaneA, PlaneB;    /* Eq. of plane of current polygon */
    GLfloat PlaneC, PlaneD;

    GLboolean ClipSpans;    /* Clip pixel spans to window? */
    GLboolean NeedNormals;    /* Are vertex normal vectors needed? */
        GLboolean FastDrawPixels;/* Use optimized glDrawPixels? */
        GLboolean MutableColors;/* Can rasterization effect colors? */

    GLboolean RGBAflag;    /* Is frame buffer in RGBA mode, not CI? */
    GLboolean DBflag;    /* Is frame buffer double buffered? */
    GLint BufferWidth;    /* Width of output buffer in pixels */
    GLint BufferHeight;    /* Height of output buffer in pixels */

    GLfloat RedScale;    /* These values are used to scale color */
    GLfloat GreenScale;    /* components from the range [0,1] to */
    GLfloat BlueScale;    /* integer values.  It should be the case */
    GLfloat AlphaScale;    /* that: scale = 2^bits - 1 where bits is */
                /* the number of bits for the component */
                /* in the frame buffer. */

        /* Gamma Correction */
        GLfloat RedGamma;       /* The gamma values, 1=linear */
        GLfloat GreenGamma;
        GLfloat BlueGamma;
        GLubyte RedRamp[256];   /* Gamma lookup tables */
        GLubyte GreenRamp[256];
        GLubyte BlueRamp[256];

    /* Special buffers (BS = BufferWidth * BufferHeight): */
    GLint *DepthBuffer;    /* Zbuffer: array [BS] of ints */
    GLubyte *StencilBuffer;    /* Stencil buffer: array [BS] of ubytes */
    ACC_TYPE *AccumBuffer;    /* Acc. buffer: array [4*BS] of components */

    GLenum ErrorValue;

    /* Current Primitive functions */
    void (*VertexFunc)( GLfloat x, GLfloat y, GLfloat z, GLfloat w );
        points_func PointsFunc;
        line_func LineFunc;
        polygon_func PolygonFunc;
        polygon_func AuxPolygonFunc;
};




extern struct gl_context CC;



/*
 * Context creation, initialization, etc.
 */

extern void gl_initialize_context( struct gl_context *c );

/*
extern struct gl_context *gl_new_context( struct gl_context *shareList );
*/

extern struct gl_context *
gl_new_context( GLboolean rgb_flag,
                GLfloat redscale,
                GLfloat greenscale,
                GLfloat bluescale,
                GLfloat alphascale,
                GLboolean db_flag,
                struct gl_context *shareList );


extern void gl_destroy_context( struct gl_context *c );

extern void gl_set_context( struct gl_context *c );

extern void gl_copy_context( struct gl_context *src, struct gl_context *dst,
                 GLuint mask );



/*
 * Miscellaneous
 */

extern void gl_error( GLenum error, char *s );


extern void gl_update_state( void );


#endif