src/mesa/swrast/s_context.h

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * 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 <keithw@vmware.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 "main/texcompress.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 (*swrast_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    /**
 140     * Byte stride between rows in ImageSlices.
 141     *
 142     * For compressed textures, this is the byte stride between one row of
 143     * blocks and the next row of blocks.
 144     *
 145     * Only valid while one of the ImageSlices is mapped, and must be the same
 146     * between all slices.
 147     */
 148    GLint RowStride;
 149    /**
 150     * When a texture image is mapped for swrast, this array contains pointers
 151     * to the beginning of each slice.
 152     *
 153     * For swrast-allocated textures, these pointers will always stay
 154     * initialized to point within Buffer.
 155     */
 156    void **ImageSlices;
 157
 158    /** Malloc'd texture memory */
 159    GLubyte *Buffer;
 160
 161    FetchTexelFunc FetchTexel;
 162
 163    /** For fetching texels from compressed textures */
 164    compressed_fetch_func FetchCompressedTexel;
 165 };
 166
 167
 168 /** cast wrapper */
 169 static inline struct swrast_texture_image *
 170 swrast_texture_image(struct gl_texture_image *img)
 171 {
 172    return (struct swrast_texture_image *) img;
 173 }
 174
 175 /** cast wrapper */
 176 static inline const struct swrast_texture_image *
 177 swrast_texture_image_const(const struct gl_texture_image *img)
 178 {
 179    return (const struct swrast_texture_image *) img;
 180 }
 181
 182
 183 /**
 184  * Subclass of gl_renderbuffer with extra fields needed for software
 185  * rendering.
 186  */
 187 struct swrast_renderbuffer
 188 {
 189    struct gl_renderbuffer Base;
 190
 191    GLubyte *Buffer;     /**< The malloc'd memory for buffer */
 192
 193    /** These fields are only valid while buffer is mapped for rendering */
 194    GLubyte *Map;
 195    GLint RowStride;    /**< in bytes */
 196
 197    /** For span rendering */
 198    GLenum ColorType;
 199 };
 200
 201
 202 /** cast wrapper */
 203 static inline struct swrast_renderbuffer *
 204 swrast_renderbuffer(struct gl_renderbuffer *img)
 205 {
 206    return (struct swrast_renderbuffer *) img;
 207 }
 208
 209
 210
 211 /**
 212  * \struct SWcontext
 213  * \brief  Per-context state that's private to the software rasterizer module.
 214  */
 215 typedef struct
 216 {
 217    /** Driver interface:
 218     */
 219    struct swrast_device_driver Driver;
 220
 221    /** Configuration mechanisms to make software rasterizer match
 222     * characteristics of the hardware rasterizer (if present):
 223     */
 224    GLboolean AllowVertexFog;
 225    GLboolean AllowPixelFog;
 226
 227    /** Derived values, invalidated on statechanges, updated from
 228     * _swrast_validate_derived():
 229     */
 230    GLbitfield _RasterMask;
 231    GLfloat _BackfaceSign;      /** +1 or -1 */
 232    GLfloat _BackfaceCullSign;  /** +1, 0, or -1 */
 233    GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */
 234    GLboolean _TextureCombinePrimary;
 235    GLboolean _FogEnabled;
 236    GLboolean _DeferredTexture;
 237
 238    /** List/array of the fragment attributes to interpolate */
 239    GLuint _ActiveAttribs[VARYING_SLOT_MAX];
 240    /** Same info, but as a bitmask of VARYING_BIT_x bits */
 241    GLbitfield64 _ActiveAttribMask;
 242    /** Number of fragment attributes to interpolate */
 243    GLuint _NumActiveAttribs;
 244    /** Indicates how each attrib is to be interpolated (lines/tris) */
 245    GLenum _InterpMode[VARYING_SLOT_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
 246
 247    /* Working values:
 248     */
 249    GLuint StippleCounter;    /**< Line stipple counter */
 250    GLuint PointLineFacing;
 251    GLbitfield NewState;
 252    GLuint StateChanges;
 253    GLenum Primitive;    /* current primitive being drawn (ala glBegin) */
 254    GLboolean SpecularVertexAdd; /**< Add specular/secondary color per vertex */
 255
 256    void (*InvalidateState)( struct gl_context *ctx, GLbitfield new_state );
 257
 258    /**
 259     * When the NewState mask intersects these masks, we invalidate the
 260     * Point/Line/Triangle function pointers below.
 261     */
 262    /*@{*/
 263    GLbitfield InvalidatePointMask;
 264    GLbitfield InvalidateLineMask;
 265    GLbitfield InvalidateTriangleMask;
 266    /*@}*/
 267
 268    /**
 269     * Device drivers plug in functions for these callbacks.
 270     * Will be called when the GL state change mask intersects the above masks.
 271     */
 272    /*@{*/
 273    void (*choose_point)( struct gl_context * );
 274    void (*choose_line)( struct gl_context * );
 275    void (*choose_triangle)( struct gl_context * );
 276    /*@}*/
 277
 278    /**
 279     * Current point, line and triangle drawing functions.
 280     */
 281    /*@{*/
 282    swrast_point_func Point;
 283    swrast_line_func Line;
 284    swrast_tri_func Triangle;
 285    /*@}*/
 286
 287    /**
 288     * Placeholders for when separate specular (or secondary color) is
 289     * enabled but texturing is not.
 290     */
 291    /*@{*/
 292    swrast_point_func SpecPoint;
 293    swrast_line_func SpecLine;
 294    swrast_tri_func SpecTriangle;
 295    /*@}*/
 296
 297    /**
 298     * Typically, we'll allocate a sw_span structure as a local variable
 299     * and set its 'array' pointer to point to this object.  The reason is
 300     * this object is big and causes problems when allocated on the stack
 301     * on some systems.
 302     */
 303    SWspanarrays *SpanArrays;
 304    SWspanarrays *ZoomedArrays;  /**< For pixel zooming */
 305
 306    /**
 307     * Used to buffer N GL_POINTS, instead of rendering one by one.
 308     */
 309    SWspan PointSpan;
 310
 311    /** Internal hooks, kept up to date by the same mechanism as above.
 312     */
 313    swrast_blend_func BlendFunc;
 314    texture_sample_func TextureSample[MAX_COMBINED_TEXTURE_IMAGE_UNITS];
 315
 316    /** Buffer for saving the sampled texture colors.
 317     * Needed for GL_ARB_texture_env_crossbar implementation.
 318     */
 319    GLfloat *TexelBuffer;
 320
 321    validate_texture_image_func ValidateTextureImage;
 322
 323    /** State used during execution of fragment programs */
 324    struct gl_program_machine FragProgMachine;
 325
 326    /** Temporary arrays for stencil operations.  To avoid large stack
 327     * allocations.
 328     */
 329    struct {
 330       GLubyte *buf1, *buf2, *buf3, *buf4;
 331    } stencil_temp;
 332
 333 } SWcontext;
 334
 335
 336 extern void
 337 _swrast_validate_derived( struct gl_context *ctx );
 338
 339 extern void
 340 _swrast_update_texture_samplers(struct gl_context *ctx);
 341
 342
 343 /** Return SWcontext for the given struct gl_context */
 344 static inline SWcontext *
 345 SWRAST_CONTEXT(struct gl_context *ctx)
 346 {
 347    return (SWcontext *) ctx->swrast_context;
 348 }
 349
 350 /** const version of above */
 351 static inline const SWcontext *
 352 CONST_SWRAST_CONTEXT(const struct gl_context *ctx)
 353 {
 354    return (const SWcontext *) ctx->swrast_context;
 355 }
 356
 357
 358 /**
 359  * Called prior to framebuffer reading/writing.
 360  * For drivers that rely on swrast for fallback rendering, this is the
 361  * driver's opportunity to map renderbuffers and textures.
 362  */
 363 static inline void
 364 swrast_render_start(struct gl_context *ctx)
 365 {
 366    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 367    if (swrast->Driver.SpanRenderStart)
 368       swrast->Driver.SpanRenderStart(ctx);
 369 }
 370
 371
 372 /** Called after framebuffer reading/writing */
 373 static inline void
 374 swrast_render_finish(struct gl_context *ctx)
 375 {
 376    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 377    if (swrast->Driver.SpanRenderFinish)
 378       swrast->Driver.SpanRenderFinish(ctx);
 379 }
 380
 381
 382 extern void
 383 _swrast_span_render_start(struct gl_context *ctx);
 384
 385 extern void
 386 _swrast_span_render_finish(struct gl_context *ctx);
 387
 388 extern void
 389 _swrast_map_textures(struct gl_context *ctx);
 390
 391 extern void
 392 _swrast_unmap_textures(struct gl_context *ctx);
 393
 394 extern unsigned int
 395 _swrast_teximage_slice_height(struct gl_texture_image *texImage);
 396
 397 extern void
 398 _swrast_map_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 399
 400 extern void
 401 _swrast_unmap_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 402
 403
 404 extern void
 405 _swrast_map_renderbuffers(struct gl_context *ctx);
 406
 407 extern void
 408 _swrast_unmap_renderbuffers(struct gl_context *ctx);
 409
 410
 411 /**
 412  * Size of an RGBA pixel, in bytes, for given datatype.
 413  */
 414 #define RGBA_PIXEL_SIZE(TYPE)                                     \
 415          ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \
 416           ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \
 417            : 4 * sizeof(GLfloat)))
 418
 419
 420
 421 /*
 422  * Fixed point arithmetic macros
 423  */
 424 #ifndef FIXED_FRAC_BITS
 425 #define FIXED_FRAC_BITS 11
 426 #endif
 427
 428 #define FIXED_SHIFT     FIXED_FRAC_BITS
 429 #define FIXED_ONE       (1 << FIXED_SHIFT)
 430 #define FIXED_HALF      (1 << (FIXED_SHIFT-1))
 431 #define FIXED_FRAC_MASK (FIXED_ONE - 1)
 432 #define FIXED_INT_MASK  (~FIXED_FRAC_MASK)
 433 #define FIXED_EPSILON   1
 434 #define FIXED_SCALE     ((float) FIXED_ONE)
 435 #define FIXED_DBL_SCALE ((double) FIXED_ONE)
 436 #define FloatToFixed(X) (IROUND((X) * FIXED_SCALE))
 437 #define FixedToDouble(X) ((X) * (1.0 / FIXED_DBL_SCALE))
 438 #define IntToFixed(I)   ((I) << FIXED_SHIFT)
 439 #define FixedToInt(X)   ((X) >> FIXED_SHIFT)
 440 #define FixedToUns(X)   (((unsigned int)(X)) >> FIXED_SHIFT)
 441 #define FixedCeil(X)    (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)
 442 #define FixedFloor(X)   ((X) & FIXED_INT_MASK)
 443 #define FixedToFloat(X) ((X) * (1.0F / FIXED_SCALE))
 444 #define PosFloatToFixed(X)      FloatToFixed(X)
 445 #define SignedFloatToFixed(X)   FloatToFixed(X)
 446
 447
 448
 449 /*
 450  * XXX these macros are just bandages for now in order to make
 451  * CHAN_BITS==32 compile cleanly.
 452  * These should probably go elsewhere at some point.
 453  */
 454 #if CHAN_TYPE == GL_FLOAT
 455 #define ChanToFixed(X)  (X)
 456 #define FixedToChan(X)  (X)
 457 #else
 458 #define ChanToFixed(X)  IntToFixed(X)
 459 #define FixedToChan(X)  FixedToInt(X)
 460 #endif
 461
 462
 463 /**
 464  * For looping over fragment attributes in the pointe, line
 465  * triangle rasterizers.
 466  */
 467 #define ATTRIB_LOOP_BEGIN                                \
 468    {                                                     \
 469       GLuint a;                                          \
 470       for (a = 0; a < swrast->_NumActiveAttribs; a++) {  \
 471          const GLuint attr = swrast->_ActiveAttribs[a];
 472
 473 #define ATTRIB_LOOP_END } }
 474
 475
 476 /**
 477  * Return the address of a pixel value in a mapped renderbuffer.
 478  */
 479 static inline GLubyte *
 480 _swrast_pixel_address(struct gl_renderbuffer *rb, GLint x, GLint y)
 481 {
 482    struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
 483    const GLint bpp = _mesa_get_format_bytes(rb->Format);
 484    const GLint rowStride = srb->RowStride;
 485    assert(x >= 0);
 486    assert(y >= 0);
 487    /* NOTE: using <= only because of s_tritemp.h which gets a pixel
 488     * address but doesn't necessarily access it.
 489     */
 490    assert(x <= (GLint) rb->Width);
 491    assert(y <= (GLint) rb->Height);
 492    assert(srb->Map);
 493    return (GLubyte *) srb->Map + y * rowStride + x * bpp;
 494 }
 495
 496
 497
 498 #endif