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