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
 160    /** Malloc'd texture memory */
 161    GLubyte *Buffer;
 162
 163    FetchTexelFunc FetchTexel;
 164
 165    /** For fetching texels from compressed textures */
 166    compressed_fetch_func FetchCompressedTexel;
 167 };
 168
 169
 170 /** cast wrapper */
 171 static inline struct swrast_texture_image *
 172 swrast_texture_image(struct gl_texture_image *img)
 173 {
 174    return (struct swrast_texture_image *) img;
 175 }
 176
 177 /** cast wrapper */
 178 static inline const struct swrast_texture_image *
 179 swrast_texture_image_const(const struct gl_texture_image *img)
 180 {
 181    return (const struct swrast_texture_image *) img;
 182 }
 183
 184
 185 /**
 186  * Subclass of gl_renderbuffer with extra fields needed for software
 187  * rendering.
 188  */
 189 struct swrast_renderbuffer
 190 {
 191    struct gl_renderbuffer Base;
 192
 193    GLubyte *Buffer;     /**< The malloc'd memory for buffer */
 194
 195    /** These fields are only valid while buffer is mapped for rendering */
 196    GLubyte *Map;
 197    GLint RowStride;    /**< in bytes */
 198
 199    /** For span rendering */
 200    GLenum ColorType;
 201 };
 202
 203
 204 /** cast wrapper */
 205 static inline struct swrast_renderbuffer *
 206 swrast_renderbuffer(struct gl_renderbuffer *img)
 207 {
 208    return (struct swrast_renderbuffer *) img;
 209 }
 210
 211
 212
 213 /**
 214  * \struct SWcontext
 215  * \brief  Per-context state that's private to the software rasterizer module.
 216  */
 217 typedef struct
 218 {
 219    /** Driver interface:
 220     */
 221    struct swrast_device_driver Driver;
 222
 223    /** Configuration mechanisms to make software rasterizer match
 224     * characteristics of the hardware rasterizer (if present):
 225     */
 226    GLboolean AllowVertexFog;
 227    GLboolean AllowPixelFog;
 228
 229    /** Derived values, invalidated on statechanges, updated from
 230     * _swrast_validate_derived():
 231     */
 232    GLbitfield _RasterMask;
 233    GLfloat _BackfaceSign;      /** +1 or -1 */
 234    GLfloat _BackfaceCullSign;  /** +1, 0, or -1 */
 235    GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */
 236    GLboolean _TextureCombinePrimary;
 237    GLboolean _FogEnabled;
 238    GLboolean _DeferredTexture;
 239
 240    /** List/array of the fragment attributes to interpolate */
 241    GLuint _ActiveAttribs[VARYING_SLOT_MAX];
 242    /** Same info, but as a bitmask of VARYING_BIT_x bits */
 243    GLbitfield64 _ActiveAttribMask;
 244    /** Number of fragment attributes to interpolate */
 245    GLuint _NumActiveAttribs;
 246    /** Indicates how each attrib is to be interpolated (lines/tris) */
 247    GLenum _InterpMode[VARYING_SLOT_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
 248
 249    /* Working values:
 250     */
 251    GLuint StippleCounter;    /**< Line stipple counter */
 252    GLuint PointLineFacing;
 253    GLbitfield NewState;
 254    GLuint StateChanges;
 255    GLenum Primitive;    /* current primitive being drawn (ala glBegin) */
 256    GLboolean SpecularVertexAdd; /**< Add specular/secondary color per vertex */
 257
 258    void (*InvalidateState)( struct gl_context *ctx, GLbitfield new_state );
 259
 260    /**
 261     * When the NewState mask intersects these masks, we invalidate the
 262     * Point/Line/Triangle function pointers below.
 263     */
 264    /*@{*/
 265    GLbitfield InvalidatePointMask;
 266    GLbitfield InvalidateLineMask;
 267    GLbitfield InvalidateTriangleMask;
 268    /*@}*/
 269
 270    /**
 271     * Device drivers plug in functions for these callbacks.
 272     * Will be called when the GL state change mask intersects the above masks.
 273     */
 274    /*@{*/
 275    void (*choose_point)( struct gl_context * );
 276    void (*choose_line)( struct gl_context * );
 277    void (*choose_triangle)( struct gl_context * );
 278    /*@}*/
 279
 280    /**
 281     * Current point, line and triangle drawing functions.
 282     */
 283    /*@{*/
 284    swrast_point_func Point;
 285    swrast_line_func Line;
 286    swrast_tri_func Triangle;
 287    /*@}*/
 288
 289    /**
 290     * Placeholders for when separate specular (or secondary color) is
 291     * enabled but texturing is not.
 292     */
 293    /*@{*/
 294    swrast_point_func SpecPoint;
 295    swrast_line_func SpecLine;
 296    swrast_tri_func SpecTriangle;
 297    /*@}*/
 298
 299    /**
 300     * Typically, we'll allocate a sw_span structure as a local variable
 301     * and set its 'array' pointer to point to this object.  The reason is
 302     * this object is big and causes problems when allocated on the stack
 303     * on some systems.
 304     */
 305    SWspanarrays *SpanArrays;
 306    SWspanarrays *ZoomedArrays;  /**< For pixel zooming */
 307
 308    /**
 309     * Used to buffer N GL_POINTS, instead of rendering one by one.
 310     */
 311    SWspan PointSpan;
 312
 313    /** Internal hooks, kept up to date by the same mechanism as above.
 314     */
 315    blend_func BlendFunc;
 316    texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];
 317
 318    /** Buffer for saving the sampled texture colors.
 319     * Needed for GL_ARB_texture_env_crossbar implementation.
 320     */
 321    GLfloat *TexelBuffer;
 322
 323    validate_texture_image_func ValidateTextureImage;
 324
 325    /** State used during execution of fragment programs */
 326    struct gl_program_machine FragProgMachine;
 327
 328    /** Temporary arrays for stencil operations.  To avoid large stack
 329     * allocations.
 330     */
 331    struct {
 332       GLubyte *buf1, *buf2, *buf3, *buf4;
 333    } stencil_temp;
 334
 335 } SWcontext;
 336
 337
 338 extern void
 339 _swrast_validate_derived( struct gl_context *ctx );
 340
 341 extern void
 342 _swrast_update_texture_samplers(struct gl_context *ctx);
 343
 344
 345 /** Return SWcontext for the given struct gl_context */
 346 static inline SWcontext *
 347 SWRAST_CONTEXT(struct gl_context *ctx)
 348 {
 349    return (SWcontext *) ctx->swrast_context;
 350 }
 351
 352 /** const version of above */
 353 static inline const SWcontext *
 354 CONST_SWRAST_CONTEXT(const struct gl_context *ctx)
 355 {
 356    return (const SWcontext *) ctx->swrast_context;
 357 }
 358
 359
 360 /**
 361  * Called prior to framebuffer reading/writing.
 362  * For drivers that rely on swrast for fallback rendering, this is the
 363  * driver's opportunity to map renderbuffers and textures.
 364  */
 365 static inline void
 366 swrast_render_start(struct gl_context *ctx)
 367 {
 368    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 369    if (swrast->Driver.SpanRenderStart)
 370       swrast->Driver.SpanRenderStart(ctx);
 371 }
 372
 373
 374 /** Called after framebuffer reading/writing */
 375 static inline void
 376 swrast_render_finish(struct gl_context *ctx)
 377 {
 378    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 379    if (swrast->Driver.SpanRenderFinish)
 380       swrast->Driver.SpanRenderFinish(ctx);
 381 }
 382
 383
 384 extern void
 385 _swrast_span_render_start(struct gl_context *ctx);
 386
 387 extern void
 388 _swrast_span_render_finish(struct gl_context *ctx);
 389
 390 extern void
 391 _swrast_map_textures(struct gl_context *ctx);
 392
 393 extern void
 394 _swrast_unmap_textures(struct gl_context *ctx);
 395
 396 extern unsigned int
 397 _swrast_teximage_slice_height(struct gl_texture_image *texImage);
 398
 399 extern void
 400 _swrast_map_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 401
 402 extern void
 403 _swrast_unmap_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
 404
 405
 406 extern void
 407 _swrast_map_renderbuffers(struct gl_context *ctx);
 408
 409 extern void
 410 _swrast_unmap_renderbuffers(struct gl_context *ctx);
 411
 412
 413 /**
 414  * Size of an RGBA pixel, in bytes, for given datatype.
 415  */
 416 #define RGBA_PIXEL_SIZE(TYPE)                                     \
 417          ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \
 418           ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \
 419            : 4 * sizeof(GLfloat)))
 420
 421
 422
 423 /*
 424  * Fixed point arithmetic macros
 425  */
 426 #ifndef FIXED_FRAC_BITS
 427 #define FIXED_FRAC_BITS 11
 428 #endif
 429
 430 #define FIXED_SHIFT     FIXED_FRAC_BITS
 431 #define FIXED_ONE       (1 << FIXED_SHIFT)
 432 #define FIXED_HALF      (1 << (FIXED_SHIFT-1))
 433 #define FIXED_FRAC_MASK (FIXED_ONE - 1)
 434 #define FIXED_INT_MASK  (~FIXED_FRAC_MASK)
 435 #define FIXED_EPSILON   1
 436 #define FIXED_SCALE     ((float) FIXED_ONE)
 437 #define FIXED_DBL_SCALE ((double) FIXED_ONE)
 438 #define FloatToFixed(X) (IROUND((X) * FIXED_SCALE))
 439 #define FixedToDouble(X) ((X) * (1.0 / FIXED_DBL_SCALE))
 440 #define IntToFixed(I)   ((I) << FIXED_SHIFT)
 441 #define FixedToInt(X)   ((X) >> FIXED_SHIFT)
 442 #define FixedToUns(X)   (((unsigned int)(X)) >> FIXED_SHIFT)
 443 #define FixedCeil(X)    (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)
 444 #define FixedFloor(X)   ((X) & FIXED_INT_MASK)
 445 #define FixedToFloat(X) ((X) * (1.0F / FIXED_SCALE))
 446 #define PosFloatToFixed(X)      FloatToFixed(X)
 447 #define SignedFloatToFixed(X)   FloatToFixed(X)
 448
 449
 450
 451 /*
 452  * XXX these macros are just bandages for now in order to make
 453  * CHAN_BITS==32 compile cleanly.
 454  * These should probably go elsewhere at some point.
 455  */
 456 #if CHAN_TYPE == GL_FLOAT
 457 #define ChanToFixed(X)  (X)
 458 #define FixedToChan(X)  (X)
 459 #else
 460 #define ChanToFixed(X)  IntToFixed(X)
 461 #define FixedToChan(X)  FixedToInt(X)
 462 #endif
 463
 464
 465 /**
 466  * For looping over fragment attributes in the pointe, line
 467  * triangle rasterizers.
 468  */
 469 #define ATTRIB_LOOP_BEGIN                                \
 470    {                                                     \
 471       GLuint a;                                          \
 472       for (a = 0; a < swrast->_NumActiveAttribs; a++) {  \
 473          const GLuint attr = swrast->_ActiveAttribs[a];
 474
 475 #define ATTRIB_LOOP_END } }
 476
 477
 478 /**
 479  * Return the address of a pixel value in a mapped renderbuffer.
 480  */
 481 static inline GLubyte *
 482 _swrast_pixel_address(struct gl_renderbuffer *rb, GLint x, GLint y)
 483 {
 484    struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
 485    const GLint bpp = _mesa_get_format_bytes(rb->Format);
 486    const GLint rowStride = srb->RowStride;
 487    assert(x >= 0);
 488    assert(y >= 0);
 489    /* NOTE: using <= only because of s_tritemp.h which gets a pixel
 490     * address but doesn't necessarily access it.
 491     */
 492    assert(x <= (GLint) rb->Width);
 493    assert(y <= (GLint) rb->Height);
 494    assert(srb->Map);
 495    return (GLubyte *) srb->Map + y * rowStride + x * bpp;
 496 }
 497
 498
 499
 500 #endif