src/mesa/swrast/s_context.h

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5.3
   4  *
   5  * Copyright (C) 1999-2007  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 "main/mtypes.h"
  47 #include "shader/prog_execute.h"
  48 #include "swrast.h"
  49 #include "s_span.h"
  50
  51
  52 typedef void (*texture_sample_func)(GLcontext *ctx,
  53                                     const struct gl_texture_object *tObj,
  54                                     GLuint n, const GLfloat texcoords[][4],
  55                                     const GLfloat lambda[], GLchan rgba[][4]);
  56
  57 typedef void (_ASMAPIP blend_func)( GLcontext *ctx, GLuint n,
  58                                     const GLubyte mask[],
  59                                     GLvoid *src, const GLvoid *dst,
  60                                     GLenum chanType);
  61
  62 typedef void (*swrast_point_func)( GLcontext *ctx, const SWvertex *);
  63
  64 typedef void (*swrast_line_func)( GLcontext *ctx,
  65                                   const SWvertex *, const SWvertex *);
  66
  67 typedef void (*swrast_tri_func)( GLcontext *ctx, const SWvertex *,
  68                                  const SWvertex *, const SWvertex *);
  69
  70
  71 typedef void (*validate_texture_image_func)(GLcontext *ctx,
  72                                             struct gl_texture_object *texObj,
  73                                             GLuint face, GLuint level);
  74
  75
  76 /**
  77  * \defgroup Bitmasks
  78  * Bitmasks to indicate which rasterization options are enabled
  79  * (RasterMask)
  80  */
  81 /*@{*/
  82 #define ALPHATEST_BIT           0x001   /**< Alpha-test pixels */
  83 #define BLEND_BIT               0x002   /**< Blend pixels */
  84 #define DEPTH_BIT               0x004   /**< Depth-test pixels */
  85 #define FOG_BIT                 0x008   /**< Fog pixels */
  86 #define LOGIC_OP_BIT            0x010   /**< Apply logic op in software */
  87 #define CLIP_BIT                0x020   /**< Scissor or window clip pixels */
  88 #define STENCIL_BIT             0x040   /**< Stencil pixels */
  89 #define MASKING_BIT             0x080   /**< Do glColorMask or glIndexMask */
  90 #define MULTI_DRAW_BIT          0x400   /**< Write to more than one color- */
  91                                         /**< buffer or no buffers. */
  92 #define OCCLUSION_BIT           0x800   /**< GL_HP_occlusion_test enabled */
  93 #define TEXTURE_BIT             0x1000  /**< Texturing really enabled */
  94 #define FRAGPROG_BIT            0x2000  /**< Fragment program enabled */
  95 #define ATIFRAGSHADER_BIT       0x4000  /**< ATI Fragment shader enabled */
  96 #define CLAMPING_BIT            0x8000  /**< Clamp colors to [0,1] */
  97 /*@}*/
  98
  99 #define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS|   \
 100                                 _NEW_SCISSOR|   \
 101                                 _NEW_COLOR|     \
 102                                 _NEW_DEPTH|     \
 103                                 _NEW_FOG|       \
 104                                 _NEW_PROGRAM|   \
 105                                 _NEW_STENCIL|   \
 106                                 _NEW_TEXTURE|   \
 107                                 _NEW_VIEWPORT|  \
 108                                 _NEW_DEPTH)
 109
 110
 111 /**
 112  * \struct SWcontext
 113  * \brief  Per-context state that's private to the software rasterizer module.
 114  */
 115 typedef struct
 116 {
 117    /** Driver interface:
 118     */
 119    struct swrast_device_driver Driver;
 120
 121    /** Configuration mechanisms to make software rasterizer match
 122     * characteristics of the hardware rasterizer (if present):
 123     */
 124    GLboolean AllowVertexFog;
 125    GLboolean AllowPixelFog;
 126
 127    /** Derived values, invalidated on statechanges, updated from
 128     * _swrast_validate_derived():
 129     */
 130    GLbitfield _RasterMask;
 131    GLfloat _BackfaceSign;
 132    GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */
 133    GLboolean _AnyTextureCombine;
 134    GLboolean _FogEnabled;
 135    GLboolean _DeferredTexture;
 136    GLenum _FogMode;  /* either GL_FOG_MODE or fragment program's fog mode */
 137
 138    /** Multiple render targets */
 139    GLbitfield _ColorOutputsMask;
 140    GLuint _NumColorOutputs;
 141
 142    /** List/array of the fragment attributes to interpolate */
 143    GLuint _ActiveAttribs[FRAG_ATTRIB_MAX];
 144    /** Same info, but as a bitmask */
 145    GLbitfield _ActiveAttribMask;
 146    /** Number of fragment attributes to interpolate */
 147    GLuint _NumActiveAttribs;
 148    /** Indicates how each attrib is to be interpolated (lines/tris) */
 149    GLenum _InterpMode[FRAG_ATTRIB_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
 150
 151    /* Accum buffer temporaries.
 152     */
 153    GLboolean _IntegerAccumMode; /**< Storing unscaled integers? */
 154    GLfloat _IntegerAccumScaler; /**< Implicit scale factor */
 155
 156    /* Working values:
 157     */
 158    GLuint StippleCounter;    /**< Line stipple counter */
 159    GLbitfield NewState;
 160    GLuint StateChanges;
 161    GLenum Primitive;    /* current primitive being drawn (ala glBegin) */
 162
 163    void (*InvalidateState)( GLcontext *ctx, GLbitfield new_state );
 164
 165    /**
 166     * When the NewState mask intersects these masks, we invalidate the
 167     * Point/Line/Triangle function pointers below.
 168     */
 169    /*@{*/
 170    GLbitfield InvalidatePointMask;
 171    GLbitfield InvalidateLineMask;
 172    GLbitfield InvalidateTriangleMask;
 173    /*@}*/
 174
 175    /**
 176     * Device drivers plug in functions for these callbacks.
 177     * Will be called when the GL state change mask intersects the above masks.
 178     */
 179    /*@{*/
 180    void (*choose_point)( GLcontext * );
 181    void (*choose_line)( GLcontext * );
 182    void (*choose_triangle)( GLcontext * );
 183    /*@}*/
 184
 185    /**
 186     * Current point, line and triangle drawing functions.
 187     */
 188    /*@{*/
 189    swrast_point_func Point;
 190    swrast_line_func Line;
 191    swrast_tri_func Triangle;
 192    /*@}*/
 193
 194    /**
 195     * Placeholders for when separate specular (or secondary color) is
 196     * enabled but texturing is not.
 197     */
 198    /*@{*/
 199    swrast_point_func SpecPoint;
 200    swrast_line_func SpecLine;
 201    swrast_tri_func SpecTriangle;
 202    /*@}*/
 203
 204    /**
 205     * Typically, we'll allocate a sw_span structure as a local variable
 206     * and set its 'array' pointer to point to this object.  The reason is
 207     * this object is big and causes problems when allocated on the stack
 208     * on some systems.
 209     */
 210    SWspanarrays *SpanArrays;
 211
 212    /**
 213     * Used to buffer N GL_POINTS, instead of rendering one by one.
 214     */
 215    SWspan PointSpan;
 216
 217    /** Internal hooks, kept up to date by the same mechanism as above.
 218     */
 219    blend_func BlendFunc;
 220    texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];
 221
 222    /** Buffer for saving the sampled texture colors.
 223     * Needed for GL_ARB_texture_env_crossbar implementation.
 224     */
 225    GLchan *TexelBuffer;
 226
 227    validate_texture_image_func ValidateTextureImage;
 228
 229    /** State used during execution of fragment programs */
 230    struct gl_program_machine FragProgMachine;
 231
 232 } SWcontext;
 233
 234
 235 extern void
 236 _swrast_validate_derived( GLcontext *ctx );
 237
 238 extern void
 239 _swrast_update_texture_samplers(GLcontext *ctx);
 240
 241
 242 #define SWRAST_CONTEXT(ctx) ((SWcontext *)ctx->swrast_context)
 243
 244 #define RENDER_START(SWctx, GLctx)                      \
 245    do {                                                 \
 246       if ((SWctx)->Driver.SpanRenderStart) {            \
 247          (*(SWctx)->Driver.SpanRenderStart)(GLctx);     \
 248       }                                                 \
 249    } while (0)
 250
 251 #define RENDER_FINISH(SWctx, GLctx)                     \
 252    do {                                                 \
 253       if ((SWctx)->Driver.SpanRenderFinish) {           \
 254          (*(SWctx)->Driver.SpanRenderFinish)(GLctx);    \
 255       }                                                 \
 256    } while (0)
 257
 258
 259
 260 /**
 261  * Size of an RGBA pixel, in bytes, for given datatype.
 262  */
 263 #define RGBA_PIXEL_SIZE(TYPE)                                     \
 264          ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \
 265           ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \
 266            : 4 * sizeof(GLfloat)))
 267
 268
 269
 270 /*
 271  * XXX these macros are just bandages for now in order to make
 272  * CHAN_BITS==32 compile cleanly.
 273  * These should probably go elsewhere at some point.
 274  */
 275 #if CHAN_TYPE == GL_FLOAT
 276 #define ChanToFixed(X)  (X)
 277 #define FixedToChan(X)  (X)
 278 #else
 279 #define ChanToFixed(X)  IntToFixed(X)
 280 #define FixedToChan(X)  FixedToInt(X)
 281 #endif
 282
 283
 284 /**
 285  * For looping over fragment attributes in the pointe, line
 286  * triangle rasterizers.
 287  */
 288 #define ATTRIB_LOOP_BEGIN                                \
 289    {                                                     \
 290       GLuint a;                                          \
 291       for (a = 0; a < swrast->_NumActiveAttribs; a++) {  \
 292          const GLuint attr = swrast->_ActiveAttribs[a];
 293
 294 #define ATTRIB_LOOP_END } }
 295
 296
 297
 298 #endif