src/glsl/glsl_types.h

   1 /* -*- c++ -*- */
   2 /*
   3  * Copyright © 2009 Intel Corporation
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * 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 OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22  * DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 #pragma once
  26 #ifndef GLSL_TYPES_H
  27 #define GLSL_TYPES_H
  28
  29 #include <string.h>
  30 #include <assert.h>
  31
  32 #ifdef __cplusplus
  33 extern "C" {
  34 #endif
  35
  36 struct _mesa_glsl_parse_state;
  37 struct glsl_symbol_table;
  38
  39 extern void
  40 _mesa_glsl_initialize_types(struct _mesa_glsl_parse_state *state);
  41
  42 extern void
  43 _mesa_glsl_release_types(void);
  44
  45 #ifdef __cplusplus
  46 }
  47 #endif
  48
  49 enum glsl_base_type {
  50    GLSL_TYPE_UINT = 0,
  51    GLSL_TYPE_INT,
  52    GLSL_TYPE_FLOAT,
  53    GLSL_TYPE_DOUBLE,
  54    GLSL_TYPE_BOOL,
  55    GLSL_TYPE_SAMPLER,
  56    GLSL_TYPE_IMAGE,
  57    GLSL_TYPE_ATOMIC_UINT,
  58    GLSL_TYPE_STRUCT,
  59    GLSL_TYPE_INTERFACE,
  60    GLSL_TYPE_ARRAY,
  61    GLSL_TYPE_VOID,
  62    GLSL_TYPE_SUBROUTINE,
  63    GLSL_TYPE_ERROR
  64 };
  65
  66 enum glsl_sampler_dim {
  67    GLSL_SAMPLER_DIM_1D = 0,
  68    GLSL_SAMPLER_DIM_2D,
  69    GLSL_SAMPLER_DIM_3D,
  70    GLSL_SAMPLER_DIM_CUBE,
  71    GLSL_SAMPLER_DIM_RECT,
  72    GLSL_SAMPLER_DIM_BUF,
  73    GLSL_SAMPLER_DIM_EXTERNAL,
  74    GLSL_SAMPLER_DIM_MS
  75 };
  76
  77 enum glsl_interface_packing {
  78    GLSL_INTERFACE_PACKING_STD140,
  79    GLSL_INTERFACE_PACKING_SHARED,
  80    GLSL_INTERFACE_PACKING_PACKED
  81 };
  82
  83 enum glsl_matrix_layout {
  84    /**
  85     * The layout of the matrix is inherited from the object containing the
  86     * matrix (the top level structure or the uniform block).
  87     */
  88    GLSL_MATRIX_LAYOUT_INHERITED,
  89
  90    /**
  91     * Explicit column-major layout
  92     *
  93     * If a uniform block doesn't have an explicit layout set, it will default
  94     * to this layout.
  95     */
  96    GLSL_MATRIX_LAYOUT_COLUMN_MAJOR,
  97
  98    /**
  99     * Row-major layout
 100     */
 101    GLSL_MATRIX_LAYOUT_ROW_MAJOR
 102 };
 103
 104 #ifdef __cplusplus
 105 #include "GL/gl.h"
 106 #include "util/ralloc.h"
 107 #include "main/mtypes.h" /* for gl_texture_index, C++'s enum rules are broken */
 108
 109 struct glsl_type {
 110    GLenum gl_type;
 111    glsl_base_type base_type;
 112
 113    unsigned sampler_dimensionality:3; /**< \see glsl_sampler_dim */
 114    unsigned sampler_shadow:1;
 115    unsigned sampler_array:1;
 116    unsigned sampler_type:2;    /**< Type of data returned using this
 117                                 * sampler or image.  Only \c
 118                                 * GLSL_TYPE_FLOAT, \c GLSL_TYPE_INT,
 119                                 * and \c GLSL_TYPE_UINT are valid.
 120                                 */
 121    unsigned interface_packing:2;
 122
 123    /* Callers of this ralloc-based new need not call delete. It's
 124     * easier to just ralloc_free 'mem_ctx' (or any of its ancestors). */
 125    static void* operator new(size_t size)
 126    {
 127       mtx_lock(&glsl_type::mutex);
 128
 129       /* mem_ctx should have been created by the static members */
 130       assert(glsl_type::mem_ctx != NULL);
 131
 132       void *type;
 133
 134       type = ralloc_size(glsl_type::mem_ctx, size);
 135       assert(type != NULL);
 136
 137       mtx_unlock(&glsl_type::mutex);
 138
 139       return type;
 140    }
 141
 142    /* If the user *does* call delete, that's OK, we will just
 143     * ralloc_free in that case. */
 144    static void operator delete(void *type)
 145    {
 146       mtx_lock(&glsl_type::mutex);
 147       ralloc_free(type);
 148       mtx_unlock(&glsl_type::mutex);
 149    }
 150
 151    /**
 152     * \name Vector and matrix element counts
 153     *
 154     * For scalars, each of these values will be 1.  For non-numeric types
 155     * these will be 0.
 156     */
 157    /*@{*/
 158    uint8_t vector_elements;    /**< 1, 2, 3, or 4 vector elements. */
 159    uint8_t matrix_columns;     /**< 1, 2, 3, or 4 matrix columns. */
 160    /*@}*/
 161
 162    /**
 163     * For \c GLSL_TYPE_ARRAY, this is the length of the array.  For
 164     * \c GLSL_TYPE_STRUCT or \c GLSL_TYPE_INTERFACE, it is the number of
 165     * elements in the structure and the number of values pointed to by
 166     * \c fields.structure (below).
 167     */
 168    unsigned length;
 169
 170    /**
 171     * Name of the data type
 172     *
 173     * Will never be \c NULL.
 174     */
 175    const char *name;
 176
 177    /**
 178     * Subtype of composite data types.
 179     */
 180    union {
 181       const struct glsl_type *array;            /**< Type of array elements. */
 182       const struct glsl_type *parameters;       /**< Parameters to function. */
 183       struct glsl_struct_field *structure;      /**< List of struct fields. */
 184    } fields;
 185
 186    /**
 187     * \name Pointers to various public type singletons
 188     */
 189    /*@{*/
 190 #undef  DECL_TYPE
 191 #define DECL_TYPE(NAME, ...) \
 192    static const glsl_type *const NAME##_type;
 193 #undef  STRUCT_TYPE
 194 #define STRUCT_TYPE(NAME) \
 195    static const glsl_type *const struct_##NAME##_type;
 196 #include "builtin_type_macros.h"
 197    /*@}*/
 198
 199    /**
 200     * Convenience accessors for vector types (shorter than get_instance()).
 201     * @{
 202     */
 203    static const glsl_type *vec(unsigned components);
 204    static const glsl_type *dvec(unsigned components);
 205    static const glsl_type *ivec(unsigned components);
 206    static const glsl_type *uvec(unsigned components);
 207    static const glsl_type *bvec(unsigned components);
 208    /**@}*/
 209
 210    /**
 211     * For numeric and boolean derived types returns the basic scalar type
 212     *
 213     * If the type is a numeric or boolean scalar, vector, or matrix type,
 214     * this function gets the scalar type of the individual components.  For
 215     * all other types, including arrays of numeric or boolean types, the
 216     * error type is returned.
 217     */
 218    const glsl_type *get_base_type() const;
 219
 220    /**
 221     * Get the basic scalar type which this type aggregates.
 222     *
 223     * If the type is a numeric or boolean scalar, vector, or matrix, or an
 224     * array of any of those, this function gets the scalar type of the
 225     * individual components.  For structs and arrays of structs, this function
 226     * returns the struct type.  For samplers and arrays of samplers, this
 227     * function returns the sampler type.
 228     */
 229    const glsl_type *get_scalar_type() const;
 230
 231    /**
 232     * Get the instance of a built-in scalar, vector, or matrix type
 233     */
 234    static const glsl_type *get_instance(unsigned base_type, unsigned rows,
 235                                         unsigned columns);
 236
 237    /**
 238     * Get the instance of a sampler type
 239     */
 240    static const glsl_type *get_sampler_instance(enum glsl_sampler_dim dim,
 241                                                 bool shadow,
 242                                                 bool array,
 243                                                 glsl_base_type type);
 244
 245
 246    /**
 247     * Get the instance of an array type
 248     */
 249    static const glsl_type *get_array_instance(const glsl_type *base,
 250                                               unsigned elements);
 251
 252    /**
 253     * Get the instance of a record type
 254     */
 255    static const glsl_type *get_record_instance(const glsl_struct_field *fields,
 256                                                unsigned num_fields,
 257                                                const char *name);
 258
 259    /**
 260     * Get the instance of an interface block type
 261     */
 262    static const glsl_type *get_interface_instance(const glsl_struct_field *fields,
 263                                                   unsigned num_fields,
 264                                                   enum glsl_interface_packing packing,
 265                                                   const char *block_name);
 266
 267    /**
 268     * Get the instance of an subroutine type
 269     */
 270    static const glsl_type *get_subroutine_instance(const char *subroutine_name);
 271
 272    /**
 273     * Get the type resulting from a multiplication of \p type_a * \p type_b
 274     */
 275    static const glsl_type *get_mul_type(const glsl_type *type_a,
 276                                         const glsl_type *type_b);
 277
 278    /**
 279     * Query the total number of scalars that make up a scalar, vector or matrix
 280     */
 281    unsigned components() const
 282    {
 283       return vector_elements * matrix_columns;
 284    }
 285
 286    /**
 287     * Calculate the number of components slots required to hold this type
 288     *
 289     * This is used to determine how many uniform or varying locations a type
 290     * might occupy.
 291     */
 292    unsigned component_slots() const;
 293
 294    /**
 295     * Calculate offset between the base location of the struct in
 296     * uniform storage and a struct member.
 297     * For the initial call, length is the index of the member to find the
 298     * offset for.
 299     */
 300    unsigned record_location_offset(unsigned length) const;
 301
 302    /**
 303     * Calculate the number of unique values from glGetUniformLocation for the
 304     * elements of the type.
 305     *
 306     * This is used to allocate slots in the UniformRemapTable, the amount of
 307     * locations may not match with actual used storage space by the driver.
 308     */
 309    unsigned uniform_locations() const;
 310
 311    /**
 312     * Calculate the number of attribute slots required to hold this type
 313     *
 314     * This implements the language rules of GLSL 1.50 for counting the number
 315     * of slots used by a vertex attribute.  It also determines the number of
 316     * varying slots the type will use up in the absence of varying packing
 317     * (and thus, it can be used to measure the number of varying slots used by
 318     * the varyings that are generated by lower_packed_varyings).
 319     */
 320    unsigned count_attribute_slots() const;
 321
 322
 323    /**
 324     * Alignment in bytes of the start of this type in a std140 uniform
 325     * block.
 326     */
 327    unsigned std140_base_alignment(bool row_major) const;
 328
 329    /** Size in bytes of this type in a std140 uniform block.
 330     *
 331     * Note that this is not GL_UNIFORM_SIZE (which is the number of
 332     * elements in the array)
 333     */
 334    unsigned std140_size(bool row_major) const;
 335
 336    /**
 337     * Alignment in bytes of the start of this type in a std430 shader
 338     * storage block.
 339     */
 340    unsigned std430_base_alignment(bool row_major) const;
 341
 342    /**
 343     * Calculate array stride in bytes of this type in a std430 shader storage
 344     * block.
 345     */
 346    unsigned std430_array_stride(bool row_major) const;
 347
 348    /**
 349     * Size in bytes of this type in a std430 shader storage block.
 350     *
 351     * Note that this is not GL_BUFFER_SIZE
 352     */
 353    unsigned std430_size(bool row_major) const;
 354
 355    /**
 356     * \brief Can this type be implicitly converted to another?
 357     *
 358     * \return True if the types are identical or if this type can be converted
 359     *         to \c desired according to Section 4.1.10 of the GLSL spec.
 360     *
 361     * \verbatim
 362     * From page 25 (31 of the pdf) of the GLSL 1.50 spec, Section 4.1.10
 363     * Implicit Conversions:
 364     *
 365     *     In some situations, an expression and its type will be implicitly
 366     *     converted to a different type. The following table shows all allowed
 367     *     implicit conversions:
 368     *
 369     *     Type of expression | Can be implicitly converted to
 370     *     --------------------------------------------------
 371     *     int                  float
 372     *     uint
 373     *
 374     *     ivec2                vec2
 375     *     uvec2
 376     *
 377     *     ivec3                vec3
 378     *     uvec3
 379     *
 380     *     ivec4                vec4
 381     *     uvec4
 382     *
 383     *     There are no implicit array or structure conversions. For example,
 384     *     an array of int cannot be implicitly converted to an array of float.
 385     *     There are no implicit conversions between signed and unsigned
 386     *     integers.
 387     * \endverbatim
 388     */
 389    bool can_implicitly_convert_to(const glsl_type *desired,
 390                                   _mesa_glsl_parse_state *state) const;
 391
 392    /**
 393     * Query whether or not a type is a scalar (non-vector and non-matrix).
 394     */
 395    bool is_scalar() const
 396    {
 397       return (vector_elements == 1)
 398          && (base_type >= GLSL_TYPE_UINT)
 399          && (base_type <= GLSL_TYPE_BOOL);
 400    }
 401
 402    /**
 403     * Query whether or not a type is a vector
 404     */
 405    bool is_vector() const
 406    {
 407       return (vector_elements > 1)
 408          && (matrix_columns == 1)
 409          && (base_type >= GLSL_TYPE_UINT)
 410          && (base_type <= GLSL_TYPE_BOOL);
 411    }
 412
 413    /**
 414     * Query whether or not a type is a matrix
 415     */
 416    bool is_matrix() const
 417    {
 418       /* GLSL only has float matrices. */
 419       return (matrix_columns > 1) && (base_type == GLSL_TYPE_FLOAT || base_type == GLSL_TYPE_DOUBLE);
 420    }
 421
 422    /**
 423     * Query whether or not a type is a non-array numeric type
 424     */
 425    bool is_numeric() const
 426    {
 427       return (base_type >= GLSL_TYPE_UINT) && (base_type <= GLSL_TYPE_DOUBLE);
 428    }
 429
 430    /**
 431     * Query whether or not a type is an integral type
 432     */
 433    bool is_integer() const
 434    {
 435       return (base_type == GLSL_TYPE_UINT) || (base_type == GLSL_TYPE_INT);
 436    }
 437
 438    /**
 439     * Query whether or not type is an integral type, or for struct and array
 440     * types, contains an integral type.
 441     */
 442    bool contains_integer() const;
 443
 444    /**
 445     * Query whether or not type is a double type, or for struct and array
 446     * types, contains a double type.
 447     */
 448    bool contains_double() const;
 449
 450    /**
 451     * Query whether or not a type is a float type
 452     */
 453    bool is_float() const
 454    {
 455       return base_type == GLSL_TYPE_FLOAT;
 456    }
 457
 458    /**
 459     * Query whether or not a type is a double type
 460     */
 461    bool is_double() const
 462    {
 463       return base_type == GLSL_TYPE_DOUBLE;
 464    }
 465
 466    /**
 467     * Query whether or not a type is a non-array boolean type
 468     */
 469    bool is_boolean() const
 470    {
 471       return base_type == GLSL_TYPE_BOOL;
 472    }
 473
 474    /**
 475     * Query whether or not a type is a sampler
 476     */
 477    bool is_sampler() const
 478    {
 479       return base_type == GLSL_TYPE_SAMPLER;
 480    }
 481
 482    /**
 483     * Query whether or not type is a sampler, or for struct and array
 484     * types, contains a sampler.
 485     */
 486    bool contains_sampler() const;
 487
 488    /**
 489     * Get the Mesa texture target index for a sampler type.
 490     */
 491    gl_texture_index sampler_index() const;
 492
 493    /**
 494     * Query whether or not type is an image, or for struct and array
 495     * types, contains an image.
 496     */
 497    bool contains_image() const;
 498
 499    /**
 500     * Query whether or not a type is an image
 501     */
 502    bool is_image() const
 503    {
 504       return base_type == GLSL_TYPE_IMAGE;
 505    }
 506
 507    /**
 508     * Query whether or not a type is an array
 509     */
 510    bool is_array() const
 511    {
 512       return base_type == GLSL_TYPE_ARRAY;
 513    }
 514
 515    /**
 516     * Query whether or not a type is a record
 517     */
 518    bool is_record() const
 519    {
 520       return base_type == GLSL_TYPE_STRUCT;
 521    }
 522
 523    /**
 524     * Query whether or not a type is an interface
 525     */
 526    bool is_interface() const
 527    {
 528       return base_type == GLSL_TYPE_INTERFACE;
 529    }
 530
 531    /**
 532     * Query whether or not a type is the void type singleton.
 533     */
 534    bool is_void() const
 535    {
 536       return base_type == GLSL_TYPE_VOID;
 537    }
 538
 539    /**
 540     * Query whether or not a type is the error type singleton.
 541     */
 542    bool is_error() const
 543    {
 544       return base_type == GLSL_TYPE_ERROR;
 545    }
 546
 547    /**
 548     * Query if a type is unnamed/anonymous (named by the parser)
 549     */
 550
 551    bool is_subroutine() const
 552    {
 553       return base_type == GLSL_TYPE_SUBROUTINE;
 554    }
 555    bool contains_subroutine() const;
 556
 557    bool is_anonymous() const
 558    {
 559       return !strncmp(name, "#anon", 5);
 560    }
 561
 562    /**
 563     * Get the type stripped of any arrays
 564     *
 565     * \return
 566     * Pointer to the type of elements of the first non-array type for array
 567     * types, or pointer to itself for non-array types.
 568     */
 569    const glsl_type *without_array() const
 570    {
 571       const glsl_type *t = this;
 572
 573       while (t->is_array())
 574          t = t->fields.array;
 575
 576       return t;
 577    }
 578
 579    /**
 580     * Return the amount of atomic counter storage required for a type.
 581     */
 582    unsigned atomic_size() const
 583    {
 584       if (base_type == GLSL_TYPE_ATOMIC_UINT)
 585          return ATOMIC_COUNTER_SIZE;
 586       else if (is_array())
 587          return length * fields.array->atomic_size();
 588       else
 589          return 0;
 590    }
 591
 592    /**
 593     * Return whether a type contains any atomic counters.
 594     */
 595    bool contains_atomic() const
 596    {
 597       return atomic_size() > 0;
 598    }
 599
 600    /**
 601     * Return whether a type contains any opaque types.
 602     */
 603    bool contains_opaque() const;
 604
 605    /**
 606     * Query the full type of a matrix row
 607     *
 608     * \return
 609     * If the type is not a matrix, \c glsl_type::error_type is returned.
 610     * Otherwise a type matching the rows of the matrix is returned.
 611     */
 612    const glsl_type *row_type() const
 613    {
 614       return is_matrix()
 615          ? get_instance(base_type, matrix_columns, 1)
 616          : error_type;
 617    }
 618
 619    /**
 620     * Query the full type of a matrix column
 621     *
 622     * \return
 623     * If the type is not a matrix, \c glsl_type::error_type is returned.
 624     * Otherwise a type matching the columns of the matrix is returned.
 625     */
 626    const glsl_type *column_type() const
 627    {
 628       return is_matrix()
 629          ? get_instance(base_type, vector_elements, 1)
 630          : error_type;
 631    }
 632
 633    /**
 634     * Get the type of a structure field
 635     *
 636     * \return
 637     * Pointer to the type of the named field.  If the type is not a structure
 638     * or the named field does not exist, \c glsl_type::error_type is returned.
 639     */
 640    const glsl_type *field_type(const char *name) const;
 641
 642    /**
 643     * Get the location of a field within a record type
 644     */
 645    int field_index(const char *name) const;
 646
 647    /**
 648     * Query the number of elements in an array type
 649     *
 650     * \return
 651     * The number of elements in the array for array types or -1 for non-array
 652     * types.  If the number of elements in the array has not yet been declared,
 653     * zero is returned.
 654     */
 655    int array_size() const
 656    {
 657       return is_array() ? length : -1;
 658    }
 659
 660    /**
 661     * Query whether the array size for all dimensions has been declared.
 662     */
 663    bool is_unsized_array() const
 664    {
 665       return is_array() && length == 0;
 666    }
 667
 668    /**
 669     * Return the number of coordinate components needed for this
 670     * sampler or image type.
 671     *
 672     * This is based purely on the sampler's dimensionality.  For example, this
 673     * returns 1 for sampler1D, and 3 for sampler2DArray.
 674     *
 675     * Note that this is often different than actual coordinate type used in
 676     * a texturing built-in function, since those pack additional values (such
 677     * as the shadow comparitor or projector) into the coordinate type.
 678     */
 679    int coordinate_components() const;
 680
 681    /**
 682     * Compare a record type against another record type.
 683     *
 684     * This is useful for matching record types declared across shader stages.
 685     */
 686    bool record_compare(const glsl_type *b) const;
 687
 688 private:
 689
 690    static mtx_t mutex;
 691
 692    /**
 693     * ralloc context for all glsl_type allocations
 694     *
 695     * Set on the first call to \c glsl_type::new.
 696     */
 697    static void *mem_ctx;
 698
 699    void init_ralloc_type_ctx(void);
 700
 701    /** Constructor for vector and matrix types */
 702    glsl_type(GLenum gl_type,
 703              glsl_base_type base_type, unsigned vector_elements,
 704              unsigned matrix_columns, const char *name);
 705
 706    /** Constructor for sampler or image types */
 707    glsl_type(GLenum gl_type, glsl_base_type base_type,
 708              enum glsl_sampler_dim dim, bool shadow, bool array,
 709              unsigned type, const char *name);
 710
 711    /** Constructor for record types */
 712    glsl_type(const glsl_struct_field *fields, unsigned num_fields,
 713              const char *name);
 714
 715    /** Constructor for interface types */
 716    glsl_type(const glsl_struct_field *fields, unsigned num_fields,
 717              enum glsl_interface_packing packing, const char *name);
 718
 719    /** Constructor for array types */
 720    glsl_type(const glsl_type *array, unsigned length);
 721
 722    /** Constructor for subroutine types */
 723    glsl_type(const char *name);
 724
 725    /** Hash table containing the known array types. */
 726    static struct hash_table *array_types;
 727
 728    /** Hash table containing the known record types. */
 729    static struct hash_table *record_types;
 730
 731    /** Hash table containing the known interface types. */
 732    static struct hash_table *interface_types;
 733
 734    /** Hash table containing the known subroutine types. */
 735    static struct hash_table *subroutine_types;
 736
 737    static bool record_key_compare(const void *a, const void *b);
 738    static unsigned record_key_hash(const void *key);
 739
 740    /**
 741     * \name Built-in type flyweights
 742     */
 743    /*@{*/
 744 #undef  DECL_TYPE
 745 #define DECL_TYPE(NAME, ...) static const glsl_type _##NAME##_type;
 746 #undef  STRUCT_TYPE
 747 #define STRUCT_TYPE(NAME)        static const glsl_type _struct_##NAME##_type;
 748 #include "builtin_type_macros.h"
 749    /*@}*/
 750
 751    /**
 752     * \name Friend functions.
 753     *
 754     * These functions are friends because they must have C linkage and the
 755     * need to call various private methods or access various private static
 756     * data.
 757     */
 758    /*@{*/
 759    friend void _mesa_glsl_initialize_types(struct _mesa_glsl_parse_state *);
 760    friend void _mesa_glsl_release_types(void);
 761    /*@}*/
 762 };
 763
 764 struct glsl_struct_field {
 765    const struct glsl_type *type;
 766    const char *name;
 767
 768    /**
 769     * For interface blocks, gl_varying_slot corresponding to the input/output
 770     * if this is a built-in input/output (i.e. a member of the built-in
 771     * gl_PerVertex interface block); -1 otherwise.
 772     *
 773     * Ignored for structs.
 774     */
 775    int location;
 776
 777    /**
 778     * For interface blocks, the interpolation mode (as in
 779     * ir_variable::interpolation).  0 otherwise.
 780     */
 781    unsigned interpolation:2;
 782
 783    /**
 784     * For interface blocks, 1 if this variable uses centroid interpolation (as
 785     * in ir_variable::centroid).  0 otherwise.
 786     */
 787    unsigned centroid:1;
 788
 789    /**
 790     * For interface blocks, 1 if this variable uses sample interpolation (as
 791     * in ir_variable::sample). 0 otherwise.
 792     */
 793    unsigned sample:1;
 794
 795    /**
 796     * Layout of the matrix.  Uses glsl_matrix_layout values.
 797     */
 798    unsigned matrix_layout:2;
 799
 800    /**
 801     * For interface blocks, 1 if this variable is a per-patch input or output
 802     * (as in ir_variable::patch). 0 otherwise.
 803     */
 804    unsigned patch:1;
 805
 806    /**
 807     * For interface blocks, it has a value if this variable uses multiple vertex
 808     * streams (as in ir_variable::stream). -1 otherwise.
 809     */
 810    int stream;
 811
 812    glsl_struct_field(const struct glsl_type *_type, const char *_name)
 813       : type(_type), name(_name), location(-1), interpolation(0), centroid(0),
 814         sample(0), matrix_layout(GLSL_MATRIX_LAYOUT_INHERITED), patch(0),
 815         stream(-1)
 816    {
 817       /* empty */
 818    }
 819
 820    glsl_struct_field()
 821    {
 822       /* empty */
 823    }
 824 };
 825
 826 static inline unsigned int
 827 glsl_align(unsigned int a, unsigned int align)
 828 {
 829    return (a + align - 1) / align * align;
 830 }
 831
 832 #undef DECL_TYPE
 833 #undef STRUCT_TYPE
 834 #endif /* __cplusplus */
 835
 836 #endif /* GLSL_TYPES_H */