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/compiler.h"
  47 #include "main/mtypes.h"
  48 #include "program/prog_execute.h"
  49 #include "swrast.h"
  50 #include "s_span.h"
  51
  52
  53 typedef void (*texture_sample_func)(struct gl_context *ctx,
  54                                     const struct gl_texture_object *tObj,
  55                                     GLuint n, const GLfloat texcoords[][4],
  56                                     const GLfloat lambda[], GLfloat rgba[][4]);
  57
  58 typedef void (_ASMAPIP blend_func)( struct gl_context *ctx, GLuint n,
  59                                     const GLubyte mask[],
  60                                     GLvoid *src, const GLvoid *dst,
  61                                     GLenum chanType);
  62
  63 typedef void (*swrast_point_func)( struct gl_context *ctx, const SWvertex *);
  64
  65 typedef void (*swrast_line_func)( struct gl_context *ctx,
  66                                   const SWvertex *, const SWvertex *);
  67
  68 typedef void (*swrast_tri_func)( struct gl_context *ctx, const SWvertex *,
  69                                  const SWvertex *, const SWvertex *);
  70
  71
  72 typedef void (*validate_texture_image_func)(struct gl_context *ctx,
  73                                             struct gl_texture_object *texObj,
  74                                             GLuint face, GLuint level);
  75
  76
  77 /**
  78  * \defgroup Bitmasks
  79  * Bitmasks to indicate which rasterization options are enabled
  80  * (RasterMask)
  81  */
  82 /*@{*/
  83 #define ALPHATEST_BIT           0x001   /**< Alpha-test pixels */
  84 #define BLEND_BIT               0x002   /**< Blend pixels */
  85 #define DEPTH_BIT               0x004   /**< Depth-test pixels */
  86 #define FOG_BIT                 0x008   /**< Fog pixels */
  87 #define LOGIC_OP_BIT            0x010   /**< Apply logic op in software */
  88 #define CLIP_BIT                0x020   /**< Scissor or window clip pixels */
  89 #define STENCIL_BIT             0x040   /**< Stencil pixels */
  90 #define MASKING_BIT             0x080   /**< Do glColorMask or glIndexMask */
  91 #define MULTI_DRAW_BIT          0x400   /**< Write to more than one color- */
  92                                         /**< buffer or no buffers. */
  93 #define OCCLUSION_BIT           0x800   /**< GL_HP_occlusion_test enabled */
  94 #define TEXTURE_BIT             0x1000  /**< Texturing really enabled */
  95 #define FRAGPROG_BIT            0x2000  /**< Fragment program enabled */
  96 #define ATIFRAGSHADER_BIT       0x4000  /**< ATI Fragment shader enabled */
  97 #define CLAMPING_BIT            0x8000  /**< Clamp colors to [0,1] */
  98 /*@}*/
  99
 100 #define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS|   \
 101                                 _NEW_SCISSOR|   \
 102                                 _NEW_COLOR|     \
 103                                 _NEW_DEPTH|     \
 104                                 _NEW_FOG|       \
 105                                 _NEW_PROGRAM|   \
 106                                 _NEW_STENCIL|   \
 107                                 _NEW_TEXTURE|   \
 108                                 _NEW_VIEWPORT|  \
 109                                 _NEW_DEPTH)
 110
 111
 112 struct swrast_texture_image;
 113
 114
 115 typedef void (*FetchTexelFuncC)(const struct swrast_texture_image *texImage,
 116                                 GLint col, GLint row, GLint img,
 117                                 GLchan *texelOut);
 118
 119 /**
 120  * As above, but returns floats.
 121  * Used for depth component images and for upcoming signed/float
 122  * texture images.
 123  */
 124 typedef void (*FetchTexelFuncF)(const struct swrast_texture_image *texImage,
 125                                 GLint col, GLint row, GLint img,
 126                                 GLfloat *texelOut);
 127
 128
 129 typedef void (*StoreTexelFunc)(struct swrast_texture_image *texImage,
 130                                GLint col, GLint row, GLint img,
 131                                const void *texel);
 132
 133 /**
 134  * Subclass of gl_texture_image.
 135  * We need extra fields/info to keep tracking of mapped texture buffers,
 136  * strides and Fetch/Store functions.
 137  */
 138 struct swrast_texture_image
 139 {
 140    struct gl_texture_image Base;
 141
 142    GLboolean _IsPowerOfTwo;  /**< Are all dimensions powers of two? */
 143
 144    /** used for mipmap LOD computation */
 145    GLfloat WidthScale, HeightScale, DepthScale;
 146
 147 #if 0
 148    GLubyte *Data;    /**< The actual texture data in malloc'd memory */
 149
 150    GLint TexelSize;  /**< bytes per texel block */
 151 #endif
 152
 153    FetchTexelFuncC FetchTexelc;
 154    FetchTexelFuncF FetchTexelf;
 155    StoreTexelFunc Store;
 156
 157 #if 0
 158    /** These fields only valid when texture memory is mapped */
 159    GLubyte **SliceMaps;  /**< points to OneMap or a malloc'd array */
 160    GLint RowStride;  /**< bytes per row of blocks */
 161 #endif
 162 };
 163
 164
 165 /** cast wrapper */
 166 static inline struct swrast_texture_image *
 167 swrast_texture_image(struct gl_texture_image *img)
 168 {
 169    return (struct swrast_texture_image *) img;
 170 }
 171
 172 /** cast wrapper */
 173 static inline const struct swrast_texture_image *
 174 swrast_texture_image_const(const struct gl_texture_image *img)
 175 {
 176    return (const struct swrast_texture_image *) img;
 177 }
 178
 179
 180 /**
 181  * \struct SWcontext
 182  * \brief  Per-context state that's private to the software rasterizer module.
 183  */
 184 typedef struct
 185 {
 186    /** Driver interface:
 187     */
 188    struct swrast_device_driver Driver;
 189
 190    /** Configuration mechanisms to make software rasterizer match
 191     * characteristics of the hardware rasterizer (if present):
 192     */
 193    GLboolean AllowVertexFog;
 194    GLboolean AllowPixelFog;
 195
 196    /** Derived values, invalidated on statechanges, updated from
 197     * _swrast_validate_derived():
 198     */
 199    GLbitfield _RasterMask;
 200    GLfloat _BackfaceSign;      /** +1 or -1 */
 201    GLfloat _BackfaceCullSign;  /** +1, 0, or -1 */
 202    GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */
 203    GLboolean _TextureCombinePrimary;
 204    GLboolean _FogEnabled;
 205    GLboolean _DeferredTexture;
 206
 207    /** List/array of the fragment attributes to interpolate */
 208    GLuint _ActiveAttribs[FRAG_ATTRIB_MAX];
 209    /** Same info, but as a bitmask */
 210    GLbitfield _ActiveAttribMask;
 211    /** Number of fragment attributes to interpolate */
 212    GLuint _NumActiveAttribs;
 213    /** Indicates how each attrib is to be interpolated (lines/tris) */
 214    GLenum _InterpMode[FRAG_ATTRIB_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
 215
 216    /* Accum buffer temporaries.
 217     */
 218    GLboolean _IntegerAccumMode; /**< Storing unscaled integers? */
 219    GLfloat _IntegerAccumScaler; /**< Implicit scale factor */
 220
 221    /* Working values:
 222     */
 223    GLuint StippleCounter;    /**< Line stipple counter */
 224    GLuint PointLineFacing;
 225    GLbitfield NewState;
 226    GLuint StateChanges;
 227    GLenum Primitive;    /* current primitive being drawn (ala glBegin) */
 228    GLboolean SpecularVertexAdd; /**< Add specular/secondary color per vertex */
 229
 230    void (*InvalidateState)( struct gl_context *ctx, GLbitfield new_state );
 231
 232    /**
 233     * When the NewState mask intersects these masks, we invalidate the
 234     * Point/Line/Triangle function pointers below.
 235     */
 236    /*@{*/
 237    GLbitfield InvalidatePointMask;
 238    GLbitfield InvalidateLineMask;
 239    GLbitfield InvalidateTriangleMask;
 240    /*@}*/
 241
 242    /**
 243     * Device drivers plug in functions for these callbacks.
 244     * Will be called when the GL state change mask intersects the above masks.
 245     */
 246    /*@{*/
 247    void (*choose_point)( struct gl_context * );
 248    void (*choose_line)( struct gl_context * );
 249    void (*choose_triangle)( struct gl_context * );
 250    /*@}*/
 251
 252    /**
 253     * Current point, line and triangle drawing functions.
 254     */
 255    /*@{*/
 256    swrast_point_func Point;
 257    swrast_line_func Line;
 258    swrast_tri_func Triangle;
 259    /*@}*/
 260
 261    /**
 262     * Placeholders for when separate specular (or secondary color) is
 263     * enabled but texturing is not.
 264     */
 265    /*@{*/
 266    swrast_point_func SpecPoint;
 267    swrast_line_func SpecLine;
 268    swrast_tri_func SpecTriangle;
 269    /*@}*/
 270
 271    /**
 272     * Typically, we'll allocate a sw_span structure as a local variable
 273     * and set its 'array' pointer to point to this object.  The reason is
 274     * this object is big and causes problems when allocated on the stack
 275     * on some systems.
 276     */
 277    SWspanarrays *SpanArrays;
 278    SWspanarrays *ZoomedArrays;  /**< For pixel zooming */
 279
 280    /**
 281     * Used to buffer N GL_POINTS, instead of rendering one by one.
 282     */
 283    SWspan PointSpan;
 284
 285    /** Internal hooks, kept up to date by the same mechanism as above.
 286     */
 287    blend_func BlendFunc;
 288    texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];
 289
 290    /** Buffer for saving the sampled texture colors.
 291     * Needed for GL_ARB_texture_env_crossbar implementation.
 292     */
 293    GLfloat *TexelBuffer;
 294
 295    validate_texture_image_func ValidateTextureImage;
 296
 297    /** State used during execution of fragment programs */
 298    struct gl_program_machine FragProgMachine;
 299
 300 } SWcontext;
 301
 302
 303 extern void
 304 _swrast_validate_derived( struct gl_context *ctx );
 305
 306 extern void
 307 _swrast_update_texture_samplers(struct gl_context *ctx);
 308
 309
 310 /** Return SWcontext for the given struct gl_context */
 311 static inline SWcontext *
 312 SWRAST_CONTEXT(struct gl_context *ctx)
 313 {
 314    return (SWcontext *) ctx->swrast_context;
 315 }
 316
 317 /** const version of above */
 318 static inline const SWcontext *
 319 CONST_SWRAST_CONTEXT(const struct gl_context *ctx)
 320 {
 321    return (const SWcontext *) ctx->swrast_context;
 322 }
 323
 324
 325 /**
 326  * Called prior to framebuffer reading/writing.
 327  * For drivers that rely on swrast for fallback rendering, this is the
 328  * driver's opportunity to map renderbuffers and textures.
 329  */
 330 static inline void
 331 swrast_render_start(struct gl_context *ctx)
 332 {
 333    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 334    if (swrast->Driver.SpanRenderStart)
 335       swrast->Driver.SpanRenderStart(ctx);
 336 }
 337
 338
 339 /** Called after framebuffer reading/writing */
 340 static inline void
 341 swrast_render_finish(struct gl_context *ctx)
 342 {
 343    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 344    if (swrast->Driver.SpanRenderFinish)
 345       swrast->Driver.SpanRenderFinish(ctx);
 346 }
 347
 348
 349
 350 /**
 351  * Size of an RGBA pixel, in bytes, for given datatype.
 352  */
 353 #define RGBA_PIXEL_SIZE(TYPE)                                     \
 354          ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \
 355           ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \
 356            : 4 * sizeof(GLfloat)))
 357
 358
 359
 360 /*
 361  * Fixed point arithmetic macros
 362  */
 363 #ifndef FIXED_FRAC_BITS
 364 #define FIXED_FRAC_BITS 11
 365 #endif
 366
 367 #define FIXED_SHIFT     FIXED_FRAC_BITS
 368 #define FIXED_ONE       (1 << FIXED_SHIFT)
 369 #define FIXED_HALF      (1 << (FIXED_SHIFT-1))
 370 #define FIXED_FRAC_MASK (FIXED_ONE - 1)
 371 #define FIXED_INT_MASK  (~FIXED_FRAC_MASK)
 372 #define FIXED_EPSILON   1
 373 #define FIXED_SCALE     ((float) FIXED_ONE)
 374 #define FIXED_DBL_SCALE ((double) FIXED_ONE)
 375 #define FloatToFixed(X) (IROUND((X) * FIXED_SCALE))
 376 #define FixedToDouble(X) ((X) * (1.0 / FIXED_DBL_SCALE))
 377 #define IntToFixed(I)   ((I) << FIXED_SHIFT)
 378 #define FixedToInt(X)   ((X) >> FIXED_SHIFT)
 379 #define FixedToUns(X)   (((unsigned int)(X)) >> FIXED_SHIFT)
 380 #define FixedCeil(X)    (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)
 381 #define FixedFloor(X)   ((X) & FIXED_INT_MASK)
 382 #define FixedToFloat(X) ((X) * (1.0F / FIXED_SCALE))
 383 #define PosFloatToFixed(X)      FloatToFixed(X)
 384 #define SignedFloatToFixed(X)   FloatToFixed(X)
 385
 386
 387
 388 /*
 389  * XXX these macros are just bandages for now in order to make
 390  * CHAN_BITS==32 compile cleanly.
 391  * These should probably go elsewhere at some point.
 392  */
 393 #if CHAN_TYPE == GL_FLOAT
 394 #define ChanToFixed(X)  (X)
 395 #define FixedToChan(X)  (X)
 396 #else
 397 #define ChanToFixed(X)  IntToFixed(X)
 398 #define FixedToChan(X)  FixedToInt(X)
 399 #endif
 400
 401
 402 /**
 403  * For looping over fragment attributes in the pointe, line
 404  * triangle rasterizers.
 405  */
 406 #define ATTRIB_LOOP_BEGIN                                \
 407    {                                                     \
 408       GLuint a;                                          \
 409       for (a = 0; a < swrast->_NumActiveAttribs; a++) {  \
 410          const GLuint attr = swrast->_ActiveAttribs[a];
 411
 412 #define ATTRIB_LOOP_END } }
 413
 414
 415
 416 #endif