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