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  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23  * OTHER DEALINGS IN THE SOFTWARE.
  24  */
  25
  26
  27 /**
  28  * \file swrast/s_context.h
  29  * \brief Software rasterization context and private types.
  30  * \author Keith Whitwell <keith@tungstengraphics.com>
  31  */
  32
  33 /**
  34  * \mainpage swrast module
  35  *
  36  * This module, software rasterization, contains the software fallback
  37  * routines for drawing points, lines, triangles, bitmaps and images.
  38  * All rendering boils down to writing spans (arrays) of pixels with
  39  * particular colors.  The span-writing routines must be implemented
  40  * by the device driver.
  41  */
  42
  43
  44 #ifndef S_CONTEXT_H
  45 #define S_CONTEXT_H
  46
  47 #include "main/compiler.h"
  48 #include "main/mtypes.h"
  49 #include "main/texcompress.h"
  50 #include "program/prog_execute.h"
  51 #include "swrast.h"
  52 #include "s_fragprog.h"
  53 #include "s_span.h"
  54
  55
  56 typedef void (*texture_sample_func)(struct gl_context *ctx,
  57                                     const struct gl_sampler_object *samp,
  58                                     const struct gl_texture_object *tObj,
  59                                     GLuint n, const GLfloat texcoords[][4],
  60                                     const GLfloat lambda[], GLfloat rgba[][4]);
  61
  62 typedef void (_ASMAPIP blend_func)( struct gl_context *ctx, GLuint n,
  63                                     const GLubyte mask[],
  64                                     GLvoid *src, const GLvoid *dst,
  65                                     GLenum chanType);
  66
  67 typedef void (*swrast_point_func)( struct gl_context *ctx, const SWvertex *);
  68
  69 typedef void (*swrast_line_func)( struct gl_context *ctx,
  70                                   const SWvertex *, const SWvertex *);
  71
  72 typedef void (*swrast_tri_func)( struct gl_context *ctx, const SWvertex *,
  73                                  const SWvertex *, const SWvertex *);
  74
  75
  76 typedef void (*validate_texture_image_func)(struct gl_context *ctx,
  77                                             struct gl_texture_object *texObj,
  78                                             GLuint face, GLuint level);
  79
  80
  81 /**
  82  * \defgroup Bitmasks
  83  * Bitmasks to indicate which rasterization options are enabled
  84  * (RasterMask)
  85  */
  86 /*@{*/
  87 #define ALPHATEST_BIT           0x001   /**< Alpha-test pixels */
  88 #define BLEND_BIT               0x002   /**< Blend pixels */
  89 #define DEPTH_BIT               0x004   /**< Depth-test pixels */
  90 #define FOG_BIT                 0x008   /**< Fog pixels */
  91 #define LOGIC_OP_BIT            0x010   /**< Apply logic op in software */
  92 #define CLIP_BIT                0x020   /**< Scissor or window clip pixels */
  93 #define STENCIL_BIT             0x040   /**< Stencil pixels */
  94 #define MASKING_BIT             0x080   /**< Do glColorMask or glIndexMask */
  95 #define MULTI_DRAW_BIT          0x400   /**< Write to more than one color- */
  96                                         /**< buffer or no buffers. */
  97 #define OCCLUSION_BIT           0x800   /**< GL_HP_occlusion_test enabled */
  98 #define TEXTURE_BIT             0x1000  /**< Texturing really enabled */
  99 #define FRAGPROG_BIT            0x2000  /**< Fragment program enabled */
 100 #define ATIFRAGSHADER_BIT       0x4000  /**< ATI Fragment shader enabled */
 101 #define CLAMPING_BIT            0x8000  /**< Clamp colors to [0,1] */
 102 /*@}*/
 103
 104 #define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS|   \
 105                                 _NEW_SCISSOR|   \
 106                                 _NEW_COLOR|     \
 107                                 _NEW_DEPTH|     \
 108                                 _NEW_FOG|       \
 109                                 _NEW_PROGRAM|   \
 110                                 _NEW_STENCIL|   \
 111                                 _NEW_TEXTURE|   \
 112                                 _NEW_VIEWPORT|  \
 113                                 _NEW_DEPTH)
 114
 115
 116 struct swrast_texture_image;
 117
 118
 119 /**
 120  * Fetch a texel from texture image at given position.
 121  */
 122 typedef void (*FetchTexelFunc)(const struct swrast_texture_image *texImage,
 123                                GLint col, GLint row, GLint img,
 124                                GLfloat *texelOut);
 125
 126
 127 /**
 128  * Subclass of gl_texture_image.
 129  * We need extra fields/info to keep tracking of mapped texture buffers,
 130  * strides and Fetch functions.
 131  */
 132 struct swrast_texture_image
 133 {
 134    struct gl_texture_image Base;
 135
 136    GLboolean _IsPowerOfTwo;  /**< Are all dimensions powers of two? */
 137
 138    /** used for mipmap LOD computation */
 139    GLfloat WidthScale, HeightScale, DepthScale;
 140
 141    /**
 142     * Byte stride between rows in ImageSlices.
 143     *
 144     * For compressed textures, this is the byte stride between one row of
 145     * blocks and the next row of blocks.
 146     *
 147     * Only valid while one of the ImageSlices is mapped, and must be the same
 148     * between all slices.
 149     */
 150    GLint RowStride;
 151    /**
 152     * When a texture image is mapped for swrast, this array contains pointers
 153     * to the beginning of each slice.
 154     *
 155     * For swrast-allocated textures, these pointers will always stay
 156     * initialized to point within Buffer.
 157     */
 158    void **ImageSlices;
 159    GLubyte *Map;                /**< Pointer to mapped image memory */
 160
 161    /** Malloc'd texture memory */
 162    GLubyte *Buffer;
 163
 164    FetchTexelFunc FetchTexel;
 165
 166    /** For fetching texels from compressed textures */
 167    compressed_fetch_func FetchCompressedTexel;
 168 };
 169
 170
 171 /** cast wrapper */
 172 static inline struct swrast_texture_image *
 173 swrast_texture_image(struct gl_texture_image *img)
 174 {
 175    return (struct swrast_texture_image *) img;
 176 }
 177
 178 /** cast wrapper */
 179 static inline const struct swrast_texture_image *
 180 swrast_texture_image_const(const struct gl_texture_image *img)
 181 {
 182    return (const struct swrast_texture_image *) img;
 183 }
 184
 185
 186 /**
 187  * Subclass of gl_renderbuffer with extra fields needed for software
 188  * rendering.
 189  */
 190 struct swrast_renderbuffer
 191 {
 192    struct gl_renderbuffer Base;
 193
 194    GLubyte *Buffer;     /**< The malloc'd memory for buffer */
 195
 196    /** These fields are only valid while buffer is mapped for rendering */
 197    GLubyte *Map;
 198    GLint RowStride;    /**< in bytes */
 199
 200    /** For span rendering */
 201    GLenum ColorType;
 202 };
 203
 204
 205 /** cast wrapper */
 206 static inline struct swrast_renderbuffer *
 207 swrast_renderbuffer(struct gl_renderbuffer *img)
 208 {
 209    return (struct swrast_renderbuffer *) img;
 210 }
 211
 212
 213
 214 /**
 215  * \struct SWcontext
 216  * \brief  Per-context state that's private to the software rasterizer module.
 217  */
 218 typedef struct
 219 {
 220    /** Driver interface:
 221     */
 222    struct swrast_device_driver Driver;
 223
 224    /** Configuration mechanisms to make software rasterizer match
 225     * characteristics of the hardware rasterizer (if present):
 226     */
 227    GLboolean AllowVertexFog;
 228    GLboolean AllowPixelFog;
 229
 230    /** Derived values, invalidated on statechanges, updated from
 231     * _swrast_validate_derived():
 232     */
 233    GLbitfield _RasterMask;
 234    GLfloat _BackfaceSign;      /** +1 or -1 */
 235    GLfloat _BackfaceCullSign;  /** +1, 0, or -1 */
 236    GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */
 237    GLboolean _TextureCombinePrimary;
 238    GLboolean _FogEnabled;
 239    GLboolean _DeferredTexture;
 240
 241    /** List/array of the fragment attributes to interpolate */
 242    GLuint _ActiveAttribs[VARYING_SLOT_MAX];
 243    /** Same info, but as a bitmask of VARYING_BIT_x bits */
 244    GLbitfield64 _ActiveAttribMask;
 245    /** Number of fragment attributes to interpolate */
 246    GLuint _NumActiveAttribs;
 247    /** Indicates how each attrib is to be interpolated (lines/tris) */
 248    GLenum _InterpMode[VARYING_SLOT_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
 249
 250    /* Working values:
 251     */
 252    GLuint StippleCounter;    /**< Line stipple counter */
 253    GLuint PointLineFacing;
 254    GLbitfield NewState;
 255    GLuint StateChanges;
 256    GLenum Primitive;    /* current primitive being drawn (ala glBegin) */
 257    GLboolean SpecularVertexAdd; /**< Add specular/secondary color per vertex */
 258
 259    void (*InvalidateState)( struct gl_context *ctx, GLbitfield new_state );
 260
 261    /**
 262     * When the NewState mask intersects these masks, we invalidate the
 263     * Point/Line/Triangle function pointers below.
 264     */
 265    /*@{*/
 266    GLbitfield InvalidatePointMask;
 267    GLbitfield InvalidateLineMask;
 268    GLbitfield InvalidateTriangleMask;
 269    /*@}*/
 270
 271    /**
 272     * Device drivers plug in functions for these callbacks.
 273     * Will be called when the GL state change mask intersects the above masks.
 274     */
 275    /*@{*/
 276    void (*choose_point)( struct gl_context * );
 277    void (*choose_line)( struct gl_context * );
 278    void (*choose_triangle)( struct gl_context * );
 279    /*@}*/
 280
 281    /**
 282     * Current point, line and triangle drawing functions.
 283     */
 284    /*@{*/
 285    swrast_point_func Point;
 286    swrast_line_func Line;
 287    swrast_tri_func Triangle;
 288    /*@}*/
 289
 290    /**
 291     * Placeholders for when separate specular (or secondary color) is
 292     * enabled but texturing is not.
 293     */
 294    /*@{*/
 295    swrast_point_func SpecPoint;
 296    swrast_line_func SpecLine;
 297    swrast_tri_func SpecTriangle;
 298    /*@}*/
 299
 300    /**
 301     * Typically, we'll allocate a sw_span structure as a local variable
 302     * and set its 'array' pointer to point to this object.  The reason is
 303     * this object is big and causes problems when allocated on the stack
 304     * on some systems.
 305     */
 306    SWspanarrays *SpanArrays;
 307    SWspanarrays *ZoomedArrays;  /**< For pixel zooming */
 308
 309    /**
 310     * Used to buffer N GL_POINTS, instead of rendering one by one.
 311     */
 312    SWspan PointSpan;
 313
 314    /** Internal hooks, kept up to date by the same mechanism as above.
 315     */
 316    blend_func BlendFunc;
 317    texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];
 318
 319    /** Buffer for saving the sampled texture colors.
 320     * Needed for GL_ARB_texture_env_crossbar implementation.
 321     */
 322    GLfloat *TexelBuffer;
 323
 324    validate_texture_image_func ValidateTextureImage;
 325
 326    /** State used during execution of fragment programs */
 327    struct gl_program_machine FragProgMachine;
 328
 329    /** Temporary arrays for stencil operations.  To avoid large stack
 330     * allocations.
 331     */
 332    struct {
 333       GLubyte *buf1, *buf2, *buf3, *buf4;
 334    } stencil_temp;
 335
 336 } SWcontext;
 337
 338
 339 extern void
 340 _swrast_validate_derived( struct gl_context *ctx );
 341
 342 extern void
 343 _swrast_update_texture_samplers(struct gl_context *ctx);
 344
 345
 346 /** Return SWcontext for the given struct gl_context */
 347 static inline SWcontext *
 348 SWRAST_CONTEXT(struct gl_context *ctx)
 349 {
 350    return (SWcontext *) ctx->swrast_context;
 351 }
 352
 353 /** const version of above */
 354 static inline const SWcontext *
 355 CONST_SWRAST_CONTEXT(const struct gl_context *ctx)
 356 {
 357    return (const SWcontext *) ctx->swrast_context;
 358 }
 359
 360
 361 /**
 362  * Called prior to framebuffer reading/writing.
 363  * For drivers that rely on swrast for fallback rendering, this is the
 364  * driver's opportunity to map renderbuffers and textures.
 365  */
 366 static inline void
 367 swrast_render_start(struct gl_context *ctx)
 368 {
 369    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 370    if (swrast->Driver.SpanRenderStart)
 371       swrast->Driver.SpanRenderStart(ctx);
 372 }
 373
 374
 375 /** Called after framebuffer reading/writing */
 376 static inline void
 377 swrast_render_finish(struct gl_context *ctx)
 378 {
 379    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 380    if (swrast->Driver.SpanRenderFinish)
 381       swrast->Driver.SpanRenderFinish(ctx);
 382 }
 383
 384
 385 extern void
 386 _swrast_span_render_start(struct gl_context *ctx);
 387
 388 extern void
 389 _swrast_span_render_finish(struct gl_context *ctx);
 390
 391 extern void
 392 _swrast_map_textures(struct gl_context *ctx);
 393
 394 extern void
 395 _swrast_unmap_textures(struct gl_context *ctx);
 396
 397 extern unsigned int
 398 _swrast_teximage_slice_height(struct gl_texture_image *texImage);
 399
 400 extern void
 401 _swrast_map_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 402
 403 extern void
 404 _swrast_unmap_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 405
 406
 407 extern void
 408 _swrast_map_renderbuffers(struct gl_context *ctx);
 409
 410 extern void
 411 _swrast_unmap_renderbuffers(struct gl_context *ctx);
 412
 413
 414 /**
 415  * Size of an RGBA pixel, in bytes, for given datatype.
 416  */
 417 #define RGBA_PIXEL_SIZE(TYPE)                                     \
 418          ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \
 419           ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \
 420            : 4 * sizeof(GLfloat)))
 421
 422
 423
 424 /*
 425  * Fixed point arithmetic macros
 426  */
 427 #ifndef FIXED_FRAC_BITS
 428 #define FIXED_FRAC_BITS 11
 429 #endif
 430
 431 #define FIXED_SHIFT     FIXED_FRAC_BITS
 432 #define FIXED_ONE       (1 << FIXED_SHIFT)
 433 #define FIXED_HALF      (1 << (FIXED_SHIFT-1))
 434 #define FIXED_FRAC_MASK (FIXED_ONE - 1)
 435 #define FIXED_INT_MASK  (~FIXED_FRAC_MASK)
 436 #define FIXED_EPSILON   1
 437 #define FIXED_SCALE     ((float) FIXED_ONE)
 438 #define FIXED_DBL_SCALE ((double) FIXED_ONE)
 439 #define FloatToFixed(X) (IROUND((X) * FIXED_SCALE))
 440 #define FixedToDouble(X) ((X) * (1.0 / FIXED_DBL_SCALE))
 441 #define IntToFixed(I)   ((I) << FIXED_SHIFT)
 442 #define FixedToInt(X)   ((X) >> FIXED_SHIFT)
 443 #define FixedToUns(X)   (((unsigned int)(X)) >> FIXED_SHIFT)
 444 #define FixedCeil(X)    (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)
 445 #define FixedFloor(X)   ((X) & FIXED_INT_MASK)
 446 #define FixedToFloat(X) ((X) * (1.0F / FIXED_SCALE))
 447 #define PosFloatToFixed(X)      FloatToFixed(X)
 448 #define SignedFloatToFixed(X)   FloatToFixed(X)
 449
 450
 451
 452 /*
 453  * XXX these macros are just bandages for now in order to make
 454  * CHAN_BITS==32 compile cleanly.
 455  * These should probably go elsewhere at some point.
 456  */
 457 #if CHAN_TYPE == GL_FLOAT
 458 #define ChanToFixed(X)  (X)
 459 #define FixedToChan(X)  (X)
 460 #else
 461 #define ChanToFixed(X)  IntToFixed(X)
 462 #define FixedToChan(X)  FixedToInt(X)
 463 #endif
 464
 465
 466 /**
 467  * For looping over fragment attributes in the pointe, line
 468  * triangle rasterizers.
 469  */
 470 #define ATTRIB_LOOP_BEGIN                                \
 471    {                                                     \
 472       GLuint a;                                          \
 473       for (a = 0; a < swrast->_NumActiveAttribs; a++) {  \
 474          const GLuint attr = swrast->_ActiveAttribs[a];
 475
 476 #define ATTRIB_LOOP_END } }
 477
 478
 479 /**
 480  * Return the address of a pixel value in a mapped renderbuffer.
 481  */
 482 static inline GLubyte *
 483 _swrast_pixel_address(struct gl_renderbuffer *rb, GLint x, GLint y)
 484 {
 485    struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
 486    const GLint bpp = _mesa_get_format_bytes(rb->Format);
 487    const GLint rowStride = srb->RowStride;
 488    assert(x >= 0);
 489    assert(y >= 0);
 490    /* NOTE: using <= only because of s_tritemp.h which gets a pixel
 491     * address but doesn't necessarily access it.
 492     */
 493    assert(x <= (GLint) rb->Width);
 494    assert(y <= (GLint) rb->Height);
 495    assert(srb->Map);
 496    return (GLubyte *) srb->Map + y * rowStride + x * bpp;
 497 }
 498
 499
 500
 501 #endif