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