src/mesa/swrast/s_context.h

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5.2
   4  *
   5  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25
  26 /**
  27  * \file swrast/s_context.h
  28  * \brief Software rasterization context and private types.
  29  * \author Keith Whitwell <keith@tungstengraphics.com>
  30  */
  31
  32 /**
  33  * \mainpage swrast module
  34  *
  35  * This module, software rasterization, contains the software fallback
  36  * routines for drawing points, lines, triangles, bitmaps and images.
  37  * All rendering boils down to writing spans (arrays) of pixels with
  38  * particular colors.  The span-writing routines must be implemented
  39  * by the device driver.
  40  */
  41
  42
  43 #ifndef S_CONTEXT_H
  44 #define S_CONTEXT_H
  45
  46 #include "mtypes.h"
  47 #include "swrast.h"
  48 #include "s_span.h"
  49
  50
  51 typedef void (*texture_sample_func)(GLcontext *ctx,
  52                                     const struct gl_texture_object *tObj,
  53                                     GLuint n, const GLfloat texcoords[][4],
  54                                     const GLfloat lambda[], GLchan rgba[][4]);
  55
  56 typedef void (_ASMAPIP blend_func)( GLcontext *ctx, GLuint n,
  57                                     const GLubyte mask[],
  58                                     GLvoid *src, const GLvoid *dst,
  59                                     GLenum chanType);
  60
  61 typedef void (*swrast_point_func)( GLcontext *ctx, const SWvertex *);
  62
  63 typedef void (*swrast_line_func)( GLcontext *ctx,
  64                                   const SWvertex *, const SWvertex *);
  65
  66 typedef void (*swrast_tri_func)( GLcontext *ctx, const SWvertex *,
  67                                  const SWvertex *, const SWvertex *);
  68
  69
  70 typedef void (*validate_texture_image_func)(GLcontext *ctx,
  71                                             struct gl_texture_object *texObj,
  72                                             GLuint face, GLuint level);
  73
  74
  75 /**
  76  * \defgroup Bitmasks
  77  * Bitmasks to indicate which rasterization options are enabled
  78  * (RasterMask)
  79  */
  80 /*@{*/
  81 #define ALPHATEST_BIT           0x001   /**< Alpha-test pixels */
  82 #define BLEND_BIT               0x002   /**< Blend pixels */
  83 #define DEPTH_BIT               0x004   /**< Depth-test pixels */
  84 #define FOG_BIT                 0x008   /**< Fog pixels */
  85 #define LOGIC_OP_BIT            0x010   /**< Apply logic op in software */
  86 #define CLIP_BIT                0x020   /**< Scissor or window clip pixels */
  87 #define STENCIL_BIT             0x040   /**< Stencil pixels */
  88 #define MASKING_BIT             0x080   /**< Do glColorMask or glIndexMask */
  89 #define MULTI_DRAW_BIT          0x400   /**< Write to more than one color- */
  90                                         /**< buffer or no buffers. */
  91 #define OCCLUSION_BIT           0x800   /**< GL_HP_occlusion_test enabled */
  92 #define TEXTURE_BIT             0x1000  /**< Texturing really enabled */
  93 #define FRAGPROG_BIT            0x2000  /**< Fragment program enabled */
  94 #define ATIFRAGSHADER_BIT       0x4000  /**< ATI Fragment shader enabled */
  95 #define CLAMPING_BIT            0x8000  /**< Clamp colors to [0,1] */
  96 /*@}*/
  97
  98 #define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS|   \
  99                                 _NEW_SCISSOR|   \
 100                                 _NEW_COLOR|     \
 101                                 _NEW_DEPTH|     \
 102                                 _NEW_FOG|       \
 103                                 _NEW_PROGRAM|   \
 104                                 _NEW_STENCIL|   \
 105                                 _NEW_TEXTURE|   \
 106                                 _NEW_VIEWPORT|  \
 107                                 _NEW_DEPTH)
 108
 109
 110 /**
 111  * \struct SWcontext
 112  * \brief  Per-context state that's private to the software rasterizer module.
 113  */
 114 typedef struct
 115 {
 116    /** Driver interface:
 117     */
 118    struct swrast_device_driver Driver;
 119
 120    /** Configuration mechanisms to make software rasterizer match
 121     * characteristics of the hardware rasterizer (if present):
 122     */
 123    GLboolean AllowVertexFog;
 124    GLboolean AllowPixelFog;
 125
 126    /** Derived values, invalidated on statechanges, updated from
 127     * _swrast_validate_derived():
 128     */
 129    GLbitfield _RasterMask;
 130    GLfloat _BackfaceSign;
 131    GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */
 132    GLboolean _AnyTextureCombine;
 133    GLboolean _FogEnabled;
 134    GLenum _FogMode;  /* either GL_FOG_MODE or fragment program's fog mode */
 135
 136    /** Fragment attributes to compute during rasterization.
 137     * Mask of FRAG_BIT_* flags.
 138     */
 139    GLbitfield _FragmentAttribs;
 140    GLuint _MinFragmentAttrib;  /**< Lowest bit set in _FragmentAttribs */
 141    GLuint _MaxFragmentAttrib;  /**< Highest bit set in _FragmentAttribs + 1 */
 142
 143    /* Accum buffer temporaries.
 144     */
 145    GLboolean _IntegerAccumMode; /**< Storing unscaled integers? */
 146    GLfloat _IntegerAccumScaler; /**< Implicit scale factor */
 147
 148    /* Working values:
 149     */
 150    GLuint StippleCounter;    /**< Line stipple counter */
 151    GLbitfield NewState;
 152    GLuint StateChanges;
 153    GLenum Primitive;    /* current primitive being drawn (ala glBegin) */
 154
 155    void (*InvalidateState)( GLcontext *ctx, GLbitfield new_state );
 156
 157    /**
 158     * When the NewState mask intersects these masks, we invalidate the
 159     * Point/Line/Triangle function pointers below.
 160     */
 161    /*@{*/
 162    GLbitfield InvalidatePointMask;
 163    GLbitfield InvalidateLineMask;
 164    GLbitfield InvalidateTriangleMask;
 165    /*@}*/
 166
 167    /**
 168     * Device drivers plug in functions for these callbacks.
 169     * Will be called when the GL state change mask intersects the above masks.
 170     */
 171    /*@{*/
 172    void (*choose_point)( GLcontext * );
 173    void (*choose_line)( GLcontext * );
 174    void (*choose_triangle)( GLcontext * );
 175    /*@}*/
 176
 177    /**
 178     * Current point, line and triangle drawing functions.
 179     */
 180    /*@{*/
 181    swrast_point_func Point;
 182    swrast_line_func Line;
 183    swrast_tri_func Triangle;
 184    /*@}*/
 185
 186    /**
 187     * Placeholders for when separate specular (or secondary color) is
 188     * enabled but texturing is not.
 189     */
 190    /*@{*/
 191    swrast_point_func SpecPoint;
 192    swrast_line_func SpecLine;
 193    swrast_tri_func SpecTriangle;
 194    /*@}*/
 195
 196    /**
 197     * Typically, we'll allocate a sw_span structure as a local variable
 198     * and set its 'array' pointer to point to this object.  The reason is
 199     * this object is big and causes problems when allocated on the stack
 200     * on some systems.
 201     */
 202    SWspanarrays *SpanArrays;
 203
 204    /**
 205     * Used to buffer N GL_POINTS, instead of rendering one by one.
 206     */
 207    SWspan PointSpan;
 208
 209    /** Internal hooks, kept up to date by the same mechanism as above.
 210     */
 211    blend_func BlendFunc;
 212    texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];
 213
 214    /** Buffer for saving the sampled texture colors.
 215     * Needed for GL_ARB_texture_env_crossbar implementation.
 216     */
 217    GLchan *TexelBuffer;
 218
 219    validate_texture_image_func ValidateTextureImage;
 220
 221 } SWcontext;
 222
 223
 224 extern void
 225 _swrast_validate_derived( GLcontext *ctx );
 226
 227
 228 #define SWRAST_CONTEXT(ctx) ((SWcontext *)ctx->swrast_context)
 229
 230 #define RENDER_START(SWctx, GLctx)                      \
 231    do {                                                 \
 232       if ((SWctx)->Driver.SpanRenderStart) {            \
 233          (*(SWctx)->Driver.SpanRenderStart)(GLctx);     \
 234       }                                                 \
 235    } while (0)
 236
 237 #define RENDER_FINISH(SWctx, GLctx)                     \
 238    do {                                                 \
 239       if ((SWctx)->Driver.SpanRenderFinish) {           \
 240          (*(SWctx)->Driver.SpanRenderFinish)(GLctx);    \
 241       }                                                 \
 242    } while (0)
 243
 244
 245
 246 /**
 247  * Size of an RGBA pixel, in bytes, for given datatype.
 248  */
 249 #define RGBA_PIXEL_SIZE(TYPE)                                     \
 250          ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \
 251           ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \
 252            : 4 * sizeof(GLfloat)))
 253
 254
 255
 256 /*
 257  * XXX these macros are just bandages for now in order to make
 258  * CHAN_BITS==32 compile cleanly.
 259  * These should probably go elsewhere at some point.
 260  */
 261 #if CHAN_TYPE == GL_FLOAT
 262 #define ChanToFixed(X)  (X)
 263 #define FixedToChan(X)  (X)
 264 #else
 265 #define ChanToFixed(X)  IntToFixed(X)
 266 #define FixedToChan(X)  FixedToInt(X)
 267 #endif
 268
 269 #endif