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 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 "main/texcompress.h"
  49 #include "program/prog_execute.h"
  50 #include "swrast.h"
  51 #include "s_fragprog.h"
  52 #include "s_span.h"
  53
  54
  55 typedef void (*texture_sample_func)(struct gl_context *ctx,
  56                                     const struct gl_sampler_object *samp,
  57                                     const struct gl_texture_object *tObj,
  58                                     GLuint n, const GLfloat texcoords[][4],
  59                                     const GLfloat lambda[], GLfloat rgba[][4]);
  60
  61 typedef void (_ASMAPIP blend_func)( struct gl_context *ctx, GLuint n,
  62                                     const GLubyte mask[],
  63                                     GLvoid *src, const GLvoid *dst,
  64                                     GLenum chanType);
  65
  66 typedef void (*swrast_point_func)( struct gl_context *ctx, const SWvertex *);
  67
  68 typedef void (*swrast_line_func)( struct gl_context *ctx,
  69                                   const SWvertex *, const SWvertex *);
  70
  71 typedef void (*swrast_tri_func)( struct gl_context *ctx, const SWvertex *,
  72                                  const SWvertex *, const SWvertex *);
  73
  74
  75 typedef void (*validate_texture_image_func)(struct gl_context *ctx,
  76                                             struct gl_texture_object *texObj,
  77                                             GLuint face, GLuint level);
  78
  79
  80 /**
  81  * \defgroup Bitmasks
  82  * Bitmasks to indicate which rasterization options are enabled
  83  * (RasterMask)
  84  */
  85 /*@{*/
  86 #define ALPHATEST_BIT           0x001   /**< Alpha-test pixels */
  87 #define BLEND_BIT               0x002   /**< Blend pixels */
  88 #define DEPTH_BIT               0x004   /**< Depth-test pixels */
  89 #define FOG_BIT                 0x008   /**< Fog pixels */
  90 #define LOGIC_OP_BIT            0x010   /**< Apply logic op in software */
  91 #define CLIP_BIT                0x020   /**< Scissor or window clip pixels */
  92 #define STENCIL_BIT             0x040   /**< Stencil pixels */
  93 #define MASKING_BIT             0x080   /**< Do glColorMask or glIndexMask */
  94 #define MULTI_DRAW_BIT          0x400   /**< Write to more than one color- */
  95                                         /**< buffer or no buffers. */
  96 #define OCCLUSION_BIT           0x800   /**< GL_HP_occlusion_test enabled */
  97 #define TEXTURE_BIT             0x1000  /**< Texturing really enabled */
  98 #define FRAGPROG_BIT            0x2000  /**< Fragment program enabled */
  99 #define ATIFRAGSHADER_BIT       0x4000  /**< ATI Fragment shader enabled */
 100 #define CLAMPING_BIT            0x8000  /**< Clamp colors to [0,1] */
 101 /*@}*/
 102
 103 #define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS|   \
 104                                 _NEW_SCISSOR|   \
 105                                 _NEW_COLOR|     \
 106                                 _NEW_DEPTH|     \
 107                                 _NEW_FOG|       \
 108                                 _NEW_PROGRAM|   \
 109                                 _NEW_STENCIL|   \
 110                                 _NEW_TEXTURE|   \
 111                                 _NEW_VIEWPORT|  \
 112                                 _NEW_DEPTH)
 113
 114
 115 struct swrast_texture_image;
 116
 117
 118 /**
 119  * Fetch a texel from texture image at given position.
 120  */
 121 typedef void (*FetchTexelFunc)(const struct swrast_texture_image *texImage,
 122                                GLint col, GLint row, GLint img,
 123                                GLfloat *texelOut);
 124
 125
 126 /**
 127  * Subclass of gl_texture_image.
 128  * We need extra fields/info to keep tracking of mapped texture buffers,
 129  * strides and Fetch functions.
 130  */
 131 struct swrast_texture_image
 132 {
 133    struct gl_texture_image Base;
 134
 135    GLboolean _IsPowerOfTwo;  /**< Are all dimensions powers of two? */
 136
 137    /** used for mipmap LOD computation */
 138    GLfloat WidthScale, HeightScale, DepthScale;
 139
 140    /** These fields only valid when texture memory is mapped */
 141    GLint RowStride;             /**< Padded width in units of texels */
 142    GLuint *ImageOffsets;        /**< if 3D texture: array [Depth] of offsets to
 143                                      each 2D slice in 'Data', in texels */
 144    GLubyte *Map;                /**< Pointer to mapped image memory */
 145
 146    /** Malloc'd texture memory */
 147    GLubyte *Buffer;
 148
 149    FetchTexelFunc FetchTexel;
 150
 151    /** For fetching texels from compressed textures */
 152    compressed_fetch_func FetchCompressedTexel;
 153 };
 154
 155
 156 /** cast wrapper */
 157 static inline struct swrast_texture_image *
 158 swrast_texture_image(struct gl_texture_image *img)
 159 {
 160    return (struct swrast_texture_image *) img;
 161 }
 162
 163 /** cast wrapper */
 164 static inline const struct swrast_texture_image *
 165 swrast_texture_image_const(const struct gl_texture_image *img)
 166 {
 167    return (const struct swrast_texture_image *) img;
 168 }
 169
 170
 171 /**
 172  * Subclass of gl_renderbuffer with extra fields needed for software
 173  * rendering.
 174  */
 175 struct swrast_renderbuffer
 176 {
 177    struct gl_renderbuffer Base;
 178
 179    GLubyte *Buffer;     /**< The malloc'd memory for buffer */
 180
 181    /** These fields are only valid while buffer is mapped for rendering */
 182    GLubyte *Map;
 183    GLint RowStride;    /**< in bytes */
 184
 185    /** For span rendering */
 186    GLenum ColorType;
 187 };
 188
 189
 190 /** cast wrapper */
 191 static inline struct swrast_renderbuffer *
 192 swrast_renderbuffer(struct gl_renderbuffer *img)
 193 {
 194    return (struct swrast_renderbuffer *) img;
 195 }
 196
 197
 198
 199 /**
 200  * \struct SWcontext
 201  * \brief  Per-context state that's private to the software rasterizer module.
 202  */
 203 typedef struct
 204 {
 205    /** Driver interface:
 206     */
 207    struct swrast_device_driver Driver;
 208
 209    /** Configuration mechanisms to make software rasterizer match
 210     * characteristics of the hardware rasterizer (if present):
 211     */
 212    GLboolean AllowVertexFog;
 213    GLboolean AllowPixelFog;
 214
 215    /** Derived values, invalidated on statechanges, updated from
 216     * _swrast_validate_derived():
 217     */
 218    GLbitfield _RasterMask;
 219    GLfloat _BackfaceSign;      /** +1 or -1 */
 220    GLfloat _BackfaceCullSign;  /** +1, 0, or -1 */
 221    GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */
 222    GLboolean _TextureCombinePrimary;
 223    GLboolean _FogEnabled;
 224    GLboolean _DeferredTexture;
 225
 226    /** List/array of the fragment attributes to interpolate */
 227    GLuint _ActiveAttribs[VARYING_SLOT_MAX];
 228    /** Same info, but as a bitmask of VARYING_BIT_x bits */
 229    GLbitfield64 _ActiveAttribMask;
 230    /** Number of fragment attributes to interpolate */
 231    GLuint _NumActiveAttribs;
 232    /** Indicates how each attrib is to be interpolated (lines/tris) */
 233    GLenum _InterpMode[VARYING_SLOT_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
 234
 235    /* Working values:
 236     */
 237    GLuint StippleCounter;    /**< Line stipple counter */
 238    GLuint PointLineFacing;
 239    GLbitfield NewState;
 240    GLuint StateChanges;
 241    GLenum Primitive;    /* current primitive being drawn (ala glBegin) */
 242    GLboolean SpecularVertexAdd; /**< Add specular/secondary color per vertex */
 243
 244    void (*InvalidateState)( struct gl_context *ctx, GLbitfield new_state );
 245
 246    /**
 247     * When the NewState mask intersects these masks, we invalidate the
 248     * Point/Line/Triangle function pointers below.
 249     */
 250    /*@{*/
 251    GLbitfield InvalidatePointMask;
 252    GLbitfield InvalidateLineMask;
 253    GLbitfield InvalidateTriangleMask;
 254    /*@}*/
 255
 256    /**
 257     * Device drivers plug in functions for these callbacks.
 258     * Will be called when the GL state change mask intersects the above masks.
 259     */
 260    /*@{*/
 261    void (*choose_point)( struct gl_context * );
 262    void (*choose_line)( struct gl_context * );
 263    void (*choose_triangle)( struct gl_context * );
 264    /*@}*/
 265
 266    /**
 267     * Current point, line and triangle drawing functions.
 268     */
 269    /*@{*/
 270    swrast_point_func Point;
 271    swrast_line_func Line;
 272    swrast_tri_func Triangle;
 273    /*@}*/
 274
 275    /**
 276     * Placeholders for when separate specular (or secondary color) is
 277     * enabled but texturing is not.
 278     */
 279    /*@{*/
 280    swrast_point_func SpecPoint;
 281    swrast_line_func SpecLine;
 282    swrast_tri_func SpecTriangle;
 283    /*@}*/
 284
 285    /**
 286     * Typically, we'll allocate a sw_span structure as a local variable
 287     * and set its 'array' pointer to point to this object.  The reason is
 288     * this object is big and causes problems when allocated on the stack
 289     * on some systems.
 290     */
 291    SWspanarrays *SpanArrays;
 292    SWspanarrays *ZoomedArrays;  /**< For pixel zooming */
 293
 294    /**
 295     * Used to buffer N GL_POINTS, instead of rendering one by one.
 296     */
 297    SWspan PointSpan;
 298
 299    /** Internal hooks, kept up to date by the same mechanism as above.
 300     */
 301    blend_func BlendFunc;
 302    texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];
 303
 304    /** Buffer for saving the sampled texture colors.
 305     * Needed for GL_ARB_texture_env_crossbar implementation.
 306     */
 307    GLfloat *TexelBuffer;
 308
 309    validate_texture_image_func ValidateTextureImage;
 310
 311    /** State used during execution of fragment programs */
 312    struct gl_program_machine FragProgMachine;
 313
 314    /** Temporary arrays for stencil operations.  To avoid large stack
 315     * allocations.
 316     */
 317    struct {
 318       GLubyte *buf1, *buf2, *buf3, *buf4;
 319    } stencil_temp;
 320
 321 } SWcontext;
 322
 323
 324 extern void
 325 _swrast_validate_derived( struct gl_context *ctx );
 326
 327 extern void
 328 _swrast_update_texture_samplers(struct gl_context *ctx);
 329
 330
 331 /** Return SWcontext for the given struct gl_context */
 332 static inline SWcontext *
 333 SWRAST_CONTEXT(struct gl_context *ctx)
 334 {
 335    return (SWcontext *) ctx->swrast_context;
 336 }
 337
 338 /** const version of above */
 339 static inline const SWcontext *
 340 CONST_SWRAST_CONTEXT(const struct gl_context *ctx)
 341 {
 342    return (const SWcontext *) ctx->swrast_context;
 343 }
 344
 345
 346 /**
 347  * Called prior to framebuffer reading/writing.
 348  * For drivers that rely on swrast for fallback rendering, this is the
 349  * driver's opportunity to map renderbuffers and textures.
 350  */
 351 static inline void
 352 swrast_render_start(struct gl_context *ctx)
 353 {
 354    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 355    if (swrast->Driver.SpanRenderStart)
 356       swrast->Driver.SpanRenderStart(ctx);
 357 }
 358
 359
 360 /** Called after framebuffer reading/writing */
 361 static inline void
 362 swrast_render_finish(struct gl_context *ctx)
 363 {
 364    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 365    if (swrast->Driver.SpanRenderFinish)
 366       swrast->Driver.SpanRenderFinish(ctx);
 367 }
 368
 369
 370 extern void
 371 _swrast_span_render_start(struct gl_context *ctx);
 372
 373 extern void
 374 _swrast_span_render_finish(struct gl_context *ctx);
 375
 376 extern void
 377 _swrast_map_textures(struct gl_context *ctx);
 378
 379 extern void
 380 _swrast_unmap_textures(struct gl_context *ctx);
 381
 382 extern void
 383 _swrast_map_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 384
 385 extern void
 386 _swrast_unmap_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 387
 388
 389 extern void
 390 _swrast_map_renderbuffers(struct gl_context *ctx);
 391
 392 extern void
 393 _swrast_unmap_renderbuffers(struct gl_context *ctx);
 394
 395
 396 /**
 397  * Size of an RGBA pixel, in bytes, for given datatype.
 398  */
 399 #define RGBA_PIXEL_SIZE(TYPE)                                     \
 400          ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \
 401           ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \
 402            : 4 * sizeof(GLfloat)))
 403
 404
 405
 406 /*
 407  * Fixed point arithmetic macros
 408  */
 409 #ifndef FIXED_FRAC_BITS
 410 #define FIXED_FRAC_BITS 11
 411 #endif
 412
 413 #define FIXED_SHIFT     FIXED_FRAC_BITS
 414 #define FIXED_ONE       (1 << FIXED_SHIFT)
 415 #define FIXED_HALF      (1 << (FIXED_SHIFT-1))
 416 #define FIXED_FRAC_MASK (FIXED_ONE - 1)
 417 #define FIXED_INT_MASK  (~FIXED_FRAC_MASK)
 418 #define FIXED_EPSILON   1
 419 #define FIXED_SCALE     ((float) FIXED_ONE)
 420 #define FIXED_DBL_SCALE ((double) FIXED_ONE)
 421 #define FloatToFixed(X) (IROUND((X) * FIXED_SCALE))
 422 #define FixedToDouble(X) ((X) * (1.0 / FIXED_DBL_SCALE))
 423 #define IntToFixed(I)   ((I) << FIXED_SHIFT)
 424 #define FixedToInt(X)   ((X) >> FIXED_SHIFT)
 425 #define FixedToUns(X)   (((unsigned int)(X)) >> FIXED_SHIFT)
 426 #define FixedCeil(X)    (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)
 427 #define FixedFloor(X)   ((X) & FIXED_INT_MASK)
 428 #define FixedToFloat(X) ((X) * (1.0F / FIXED_SCALE))
 429 #define PosFloatToFixed(X)      FloatToFixed(X)
 430 #define SignedFloatToFixed(X)   FloatToFixed(X)
 431
 432
 433
 434 /*
 435  * XXX these macros are just bandages for now in order to make
 436  * CHAN_BITS==32 compile cleanly.
 437  * These should probably go elsewhere at some point.
 438  */
 439 #if CHAN_TYPE == GL_FLOAT
 440 #define ChanToFixed(X)  (X)
 441 #define FixedToChan(X)  (X)
 442 #else
 443 #define ChanToFixed(X)  IntToFixed(X)
 444 #define FixedToChan(X)  FixedToInt(X)
 445 #endif
 446
 447
 448 /**
 449  * For looping over fragment attributes in the pointe, line
 450  * triangle rasterizers.
 451  */
 452 #define ATTRIB_LOOP_BEGIN                                \
 453    {                                                     \
 454       GLuint a;                                          \
 455       for (a = 0; a < swrast->_NumActiveAttribs; a++) {  \
 456          const GLuint attr = swrast->_ActiveAttribs[a];
 457
 458 #define ATTRIB_LOOP_END } }
 459
 460
 461 /**
 462  * Return the address of a pixel value in a mapped renderbuffer.
 463  */
 464 static inline GLubyte *
 465 _swrast_pixel_address(struct gl_renderbuffer *rb, GLint x, GLint y)
 466 {
 467    struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
 468    const GLint bpp = _mesa_get_format_bytes(rb->Format);
 469    const GLint rowStride = srb->RowStride;
 470    assert(x >= 0);
 471    assert(y >= 0);
 472    /* NOTE: using <= only because of s_tritemp.h which gets a pixel
 473     * address but doesn't necessarily access it.
 474     */
 475    assert(x <= (GLint) rb->Width);
 476    assert(y <= (GLint) rb->Height);
 477    assert(srb->Map);
 478    return (GLubyte *) srb->Map + y * rowStride + x * bpp;
 479 }
 480
 481
 482
 483 #endif