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_fragprog.h"
  51 #include "s_span.h"
  52
  53
  54 typedef void (*texture_sample_func)(struct gl_context *ctx,
  55                                     const struct gl_sampler_object *samp,
  56                                     const struct gl_texture_object *tObj,
  57                                     GLuint n, const GLfloat texcoords[][4],
  58                                     const GLfloat lambda[], GLfloat rgba[][4]);
  59
  60 typedef void (_ASMAPIP blend_func)( struct gl_context *ctx, GLuint n,
  61                                     const GLubyte mask[],
  62                                     GLvoid *src, const GLvoid *dst,
  63                                     GLenum chanType);
  64
  65 typedef void (*swrast_point_func)( struct gl_context *ctx, const SWvertex *);
  66
  67 typedef void (*swrast_line_func)( struct gl_context *ctx,
  68                                   const SWvertex *, const SWvertex *);
  69
  70 typedef void (*swrast_tri_func)( struct gl_context *ctx, const SWvertex *,
  71                                  const SWvertex *, const SWvertex *);
  72
  73
  74 typedef void (*validate_texture_image_func)(struct gl_context *ctx,
  75                                             struct gl_texture_object *texObj,
  76                                             GLuint face, GLuint level);
  77
  78
  79 /**
  80  * \defgroup Bitmasks
  81  * Bitmasks to indicate which rasterization options are enabled
  82  * (RasterMask)
  83  */
  84 /*@{*/
  85 #define ALPHATEST_BIT           0x001   /**< Alpha-test pixels */
  86 #define BLEND_BIT               0x002   /**< Blend pixels */
  87 #define DEPTH_BIT               0x004   /**< Depth-test pixels */
  88 #define FOG_BIT                 0x008   /**< Fog pixels */
  89 #define LOGIC_OP_BIT            0x010   /**< Apply logic op in software */
  90 #define CLIP_BIT                0x020   /**< Scissor or window clip pixels */
  91 #define STENCIL_BIT             0x040   /**< Stencil pixels */
  92 #define MASKING_BIT             0x080   /**< Do glColorMask or glIndexMask */
  93 #define MULTI_DRAW_BIT          0x400   /**< Write to more than one color- */
  94                                         /**< buffer or no buffers. */
  95 #define OCCLUSION_BIT           0x800   /**< GL_HP_occlusion_test enabled */
  96 #define TEXTURE_BIT             0x1000  /**< Texturing really enabled */
  97 #define FRAGPROG_BIT            0x2000  /**< Fragment program enabled */
  98 #define ATIFRAGSHADER_BIT       0x4000  /**< ATI Fragment shader enabled */
  99 #define CLAMPING_BIT            0x8000  /**< Clamp colors to [0,1] */
 100 /*@}*/
 101
 102 #define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS|   \
 103                                 _NEW_SCISSOR|   \
 104                                 _NEW_COLOR|     \
 105                                 _NEW_DEPTH|     \
 106                                 _NEW_FOG|       \
 107                                 _NEW_PROGRAM|   \
 108                                 _NEW_STENCIL|   \
 109                                 _NEW_TEXTURE|   \
 110                                 _NEW_VIEWPORT|  \
 111                                 _NEW_DEPTH)
 112
 113
 114 struct swrast_texture_image;
 115
 116
 117 /**
 118  * Fetch a texel from texture image at given position.
 119  */
 120 typedef void (*FetchTexelFunc)(const struct swrast_texture_image *texImage,
 121                                GLint col, GLint row, GLint img,
 122                                GLfloat *texelOut);
 123
 124
 125 /**
 126  * Subclass of gl_texture_image.
 127  * We need extra fields/info to keep tracking of mapped texture buffers,
 128  * strides and Fetch functions.
 129  */
 130 struct swrast_texture_image
 131 {
 132    struct gl_texture_image Base;
 133
 134    GLboolean _IsPowerOfTwo;  /**< Are all dimensions powers of two? */
 135
 136    /** used for mipmap LOD computation */
 137    GLfloat WidthScale, HeightScale, DepthScale;
 138
 139    /** These fields only valid when texture memory is mapped */
 140    GLint RowStride;             /**< Padded width in units of texels */
 141    GLuint *ImageOffsets;        /**< if 3D texture: array [Depth] of offsets to
 142                                      each 2D slice in 'Data', in texels */
 143    GLubyte *Map;                /**< Pointer to mapped image memory */
 144
 145    /** Malloc'd texture memory */
 146    GLubyte *Buffer;
 147
 148    FetchTexelFunc FetchTexel;
 149 };
 150
 151
 152 /** cast wrapper */
 153 static inline struct swrast_texture_image *
 154 swrast_texture_image(struct gl_texture_image *img)
 155 {
 156    return (struct swrast_texture_image *) img;
 157 }
 158
 159 /** cast wrapper */
 160 static inline const struct swrast_texture_image *
 161 swrast_texture_image_const(const struct gl_texture_image *img)
 162 {
 163    return (const struct swrast_texture_image *) img;
 164 }
 165
 166
 167 /**
 168  * Subclass of gl_renderbuffer with extra fields needed for software
 169  * rendering.
 170  */
 171 struct swrast_renderbuffer
 172 {
 173    struct gl_renderbuffer Base;
 174
 175    GLubyte *Buffer;     /**< The malloc'd memory for buffer */
 176
 177    /** These fields are only valid while buffer is mapped for rendering */
 178    GLubyte *Map;
 179    GLint RowStride;    /**< in bytes */
 180
 181    /** For span rendering */
 182    GLenum ColorType;
 183 };
 184
 185
 186 /** cast wrapper */
 187 static inline struct swrast_renderbuffer *
 188 swrast_renderbuffer(struct gl_renderbuffer *img)
 189 {
 190    return (struct swrast_renderbuffer *) img;
 191 }
 192
 193
 194
 195 /**
 196  * \struct SWcontext
 197  * \brief  Per-context state that's private to the software rasterizer module.
 198  */
 199 typedef struct
 200 {
 201    /** Driver interface:
 202     */
 203    struct swrast_device_driver Driver;
 204
 205    /** Configuration mechanisms to make software rasterizer match
 206     * characteristics of the hardware rasterizer (if present):
 207     */
 208    GLboolean AllowVertexFog;
 209    GLboolean AllowPixelFog;
 210
 211    /** Derived values, invalidated on statechanges, updated from
 212     * _swrast_validate_derived():
 213     */
 214    GLbitfield _RasterMask;
 215    GLfloat _BackfaceSign;      /** +1 or -1 */
 216    GLfloat _BackfaceCullSign;  /** +1, 0, or -1 */
 217    GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */
 218    GLboolean _TextureCombinePrimary;
 219    GLboolean _FogEnabled;
 220    GLboolean _DeferredTexture;
 221
 222    /** List/array of the fragment attributes to interpolate */
 223    GLuint _ActiveAttribs[FRAG_ATTRIB_MAX];
 224    /** Same info, but as a bitmask of FRAG_BIT_x bits */
 225    GLbitfield64 _ActiveAttribMask;
 226    /** Number of fragment attributes to interpolate */
 227    GLuint _NumActiveAttribs;
 228    /** Indicates how each attrib is to be interpolated (lines/tris) */
 229    GLenum _InterpMode[FRAG_ATTRIB_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
 230
 231    /* Working values:
 232     */
 233    GLuint StippleCounter;    /**< Line stipple counter */
 234    GLuint PointLineFacing;
 235    GLbitfield NewState;
 236    GLuint StateChanges;
 237    GLenum Primitive;    /* current primitive being drawn (ala glBegin) */
 238    GLboolean SpecularVertexAdd; /**< Add specular/secondary color per vertex */
 239
 240    void (*InvalidateState)( struct gl_context *ctx, GLbitfield new_state );
 241
 242    /**
 243     * When the NewState mask intersects these masks, we invalidate the
 244     * Point/Line/Triangle function pointers below.
 245     */
 246    /*@{*/
 247    GLbitfield InvalidatePointMask;
 248    GLbitfield InvalidateLineMask;
 249    GLbitfield InvalidateTriangleMask;
 250    /*@}*/
 251
 252    /**
 253     * Device drivers plug in functions for these callbacks.
 254     * Will be called when the GL state change mask intersects the above masks.
 255     */
 256    /*@{*/
 257    void (*choose_point)( struct gl_context * );
 258    void (*choose_line)( struct gl_context * );
 259    void (*choose_triangle)( struct gl_context * );
 260    /*@}*/
 261
 262    /**
 263     * Current point, line and triangle drawing functions.
 264     */
 265    /*@{*/
 266    swrast_point_func Point;
 267    swrast_line_func Line;
 268    swrast_tri_func Triangle;
 269    /*@}*/
 270
 271    /**
 272     * Placeholders for when separate specular (or secondary color) is
 273     * enabled but texturing is not.
 274     */
 275    /*@{*/
 276    swrast_point_func SpecPoint;
 277    swrast_line_func SpecLine;
 278    swrast_tri_func SpecTriangle;
 279    /*@}*/
 280
 281    /**
 282     * Typically, we'll allocate a sw_span structure as a local variable
 283     * and set its 'array' pointer to point to this object.  The reason is
 284     * this object is big and causes problems when allocated on the stack
 285     * on some systems.
 286     */
 287    SWspanarrays *SpanArrays;
 288    SWspanarrays *ZoomedArrays;  /**< For pixel zooming */
 289
 290    /**
 291     * Used to buffer N GL_POINTS, instead of rendering one by one.
 292     */
 293    SWspan PointSpan;
 294
 295    /** Internal hooks, kept up to date by the same mechanism as above.
 296     */
 297    blend_func BlendFunc;
 298    texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];
 299
 300    /** Buffer for saving the sampled texture colors.
 301     * Needed for GL_ARB_texture_env_crossbar implementation.
 302     */
 303    GLfloat *TexelBuffer;
 304
 305    validate_texture_image_func ValidateTextureImage;
 306
 307    /** State used during execution of fragment programs */
 308    struct gl_program_machine FragProgMachine;
 309
 310    /** Temporary arrays for stencil operations.  To avoid large stack
 311     * allocations.
 312     */
 313    struct {
 314       GLubyte *buf1, *buf2, *buf3, *buf4;
 315    } stencil_temp;
 316
 317 } SWcontext;
 318
 319
 320 extern void
 321 _swrast_validate_derived( struct gl_context *ctx );
 322
 323 extern void
 324 _swrast_update_texture_samplers(struct gl_context *ctx);
 325
 326
 327 /** Return SWcontext for the given struct gl_context */
 328 static inline SWcontext *
 329 SWRAST_CONTEXT(struct gl_context *ctx)
 330 {
 331    return (SWcontext *) ctx->swrast_context;
 332 }
 333
 334 /** const version of above */
 335 static inline const SWcontext *
 336 CONST_SWRAST_CONTEXT(const struct gl_context *ctx)
 337 {
 338    return (const SWcontext *) ctx->swrast_context;
 339 }
 340
 341
 342 /**
 343  * Called prior to framebuffer reading/writing.
 344  * For drivers that rely on swrast for fallback rendering, this is the
 345  * driver's opportunity to map renderbuffers and textures.
 346  */
 347 static inline void
 348 swrast_render_start(struct gl_context *ctx)
 349 {
 350    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 351    if (swrast->Driver.SpanRenderStart)
 352       swrast->Driver.SpanRenderStart(ctx);
 353 }
 354
 355
 356 /** Called after framebuffer reading/writing */
 357 static inline void
 358 swrast_render_finish(struct gl_context *ctx)
 359 {
 360    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 361    if (swrast->Driver.SpanRenderFinish)
 362       swrast->Driver.SpanRenderFinish(ctx);
 363 }
 364
 365
 366 extern void
 367 _swrast_span_render_start(struct gl_context *ctx);
 368
 369 extern void
 370 _swrast_span_render_finish(struct gl_context *ctx);
 371
 372 extern void
 373 _swrast_map_textures(struct gl_context *ctx);
 374
 375 extern void
 376 _swrast_unmap_textures(struct gl_context *ctx);
 377
 378 extern void
 379 _swrast_map_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 380
 381 extern void
 382 _swrast_unmap_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 383
 384
 385 extern void
 386 _swrast_map_renderbuffers(struct gl_context *ctx);
 387
 388 extern void
 389 _swrast_unmap_renderbuffers(struct gl_context *ctx);
 390
 391
 392 /**
 393  * Size of an RGBA pixel, in bytes, for given datatype.
 394  */
 395 #define RGBA_PIXEL_SIZE(TYPE)                                     \
 396          ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \
 397           ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \
 398            : 4 * sizeof(GLfloat)))
 399
 400
 401
 402 /*
 403  * Fixed point arithmetic macros
 404  */
 405 #ifndef FIXED_FRAC_BITS
 406 #define FIXED_FRAC_BITS 11
 407 #endif
 408
 409 #define FIXED_SHIFT     FIXED_FRAC_BITS
 410 #define FIXED_ONE       (1 << FIXED_SHIFT)
 411 #define FIXED_HALF      (1 << (FIXED_SHIFT-1))
 412 #define FIXED_FRAC_MASK (FIXED_ONE - 1)
 413 #define FIXED_INT_MASK  (~FIXED_FRAC_MASK)
 414 #define FIXED_EPSILON   1
 415 #define FIXED_SCALE     ((float) FIXED_ONE)
 416 #define FIXED_DBL_SCALE ((double) FIXED_ONE)
 417 #define FloatToFixed(X) (IROUND((X) * FIXED_SCALE))
 418 #define FixedToDouble(X) ((X) * (1.0 / FIXED_DBL_SCALE))
 419 #define IntToFixed(I)   ((I) << FIXED_SHIFT)
 420 #define FixedToInt(X)   ((X) >> FIXED_SHIFT)
 421 #define FixedToUns(X)   (((unsigned int)(X)) >> FIXED_SHIFT)
 422 #define FixedCeil(X)    (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)
 423 #define FixedFloor(X)   ((X) & FIXED_INT_MASK)
 424 #define FixedToFloat(X) ((X) * (1.0F / FIXED_SCALE))
 425 #define PosFloatToFixed(X)      FloatToFixed(X)
 426 #define SignedFloatToFixed(X)   FloatToFixed(X)
 427
 428
 429
 430 /*
 431  * XXX these macros are just bandages for now in order to make
 432  * CHAN_BITS==32 compile cleanly.
 433  * These should probably go elsewhere at some point.
 434  */
 435 #if CHAN_TYPE == GL_FLOAT
 436 #define ChanToFixed(X)  (X)
 437 #define FixedToChan(X)  (X)
 438 #else
 439 #define ChanToFixed(X)  IntToFixed(X)
 440 #define FixedToChan(X)  FixedToInt(X)
 441 #endif
 442
 443
 444 /**
 445  * For looping over fragment attributes in the pointe, line
 446  * triangle rasterizers.
 447  */
 448 #define ATTRIB_LOOP_BEGIN                                \
 449    {                                                     \
 450       GLuint a;                                          \
 451       for (a = 0; a < swrast->_NumActiveAttribs; a++) {  \
 452          const GLuint attr = swrast->_ActiveAttribs[a];
 453
 454 #define ATTRIB_LOOP_END } }
 455
 456
 457 /**
 458  * Return the address of a pixel value in a mapped renderbuffer.
 459  */
 460 static inline GLubyte *
 461 _swrast_pixel_address(struct gl_renderbuffer *rb, GLint x, GLint y)
 462 {
 463    struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
 464    const GLint bpp = _mesa_get_format_bytes(rb->Format);
 465    const GLint rowStride = srb->RowStride;
 466    assert(x >= 0);
 467    assert(y >= 0);
 468    /* NOTE: using <= only because of s_tritemp.h which gets a pixel
 469     * address but doesn't necessarily access it.
 470     */
 471    assert(x <= (GLint) rb->Width);
 472    assert(y <= (GLint) rb->Height);
 473    assert(srb->Map);
 474    return (GLubyte *) srb->Map + y * rowStride + x * bpp;
 475 }
 476
 477
 478
 479 #endif