src/mesa/main/format_utils.h

   1 /**
   2  * \file format_utils.h
   3  * A collection of format conversion utility functions.
   4  */
   5
   6 /*
   7  * Mesa 3-D graphics library
   8  *
   9  * Copyright (C) 1999-2006  Brian Paul  All Rights Reserved.
  10  * Copyright (C) 2014  Intel Corporation  All Rights Reserved.
  11  *
  12  * Permission is hereby granted, free of charge, to any person obtaining a
  13  * copy of this software and associated documentation files (the "Software"),
  14  * to deal in the Software without restriction, including without limitation
  15  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  16  * and/or sell copies of the Software, and to permit persons to whom the
  17  * Software is furnished to do so, subject to the following conditions:
  18  *
  19  * The above copyright notice and this permission notice shall be included
  20  * in all copies or substantial portions of the Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  23  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  25  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  26  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  27  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  28  * OTHER DEALINGS IN THE SOFTWARE.
  29  */
  30
  31 #ifndef FORMAT_UTILS_H
  32 #define FORMAT_UTILS_H
  33
  34 #include "imports.h"
  35 #include "macros.h"
  36
  37 /* Only guaranteed to work for BITS <= 32 */
  38 #define MAX_UINT(BITS) ((BITS) == 32 ? UINT32_MAX : ((1u << (BITS)) - 1))
  39 #define MAX_INT(BITS) ((int)MAX_UINT((BITS) - 1))
  40 #define MIN_INT(BITS) ((BITS) == 32 ? INT32_MIN : (-(1 << (BITS - 1))))
  41
  42 /* Extends an integer of size SRC_BITS to one of size DST_BITS linearly */
  43 #define EXTEND_NORMALIZED_INT(X, SRC_BITS, DST_BITS) \
  44       (((X) * (int)(MAX_UINT(DST_BITS) / MAX_UINT(SRC_BITS))) + \
  45        ((DST_BITS % SRC_BITS) ? ((X) >> (SRC_BITS - DST_BITS % SRC_BITS)) : 0))
  46
  47 static inline float
  48 _mesa_unorm_to_float(unsigned x, unsigned src_bits)
  49 {
  50    return x * (1.0f / (float)MAX_UINT(src_bits));
  51 }
  52
  53 static inline float
  54 _mesa_snorm_to_float(int x, unsigned src_bits)
  55 {
  56    if (x <= -MAX_INT(src_bits))
  57       return -1.0f;
  58    else
  59       return x * (1.0f / (float)MAX_INT(src_bits));
  60 }
  61
  62 static inline uint16_t
  63 _mesa_unorm_to_half(unsigned x, unsigned src_bits)
  64 {
  65    return _mesa_float_to_half(_mesa_unorm_to_float(x, src_bits));
  66 }
  67
  68 static inline uint16_t
  69 _mesa_snorm_to_half(int x, unsigned src_bits)
  70 {
  71    return _mesa_float_to_half(_mesa_snorm_to_float(x, src_bits));
  72 }
  73
  74 static inline unsigned
  75 _mesa_float_to_unorm(float x, unsigned dst_bits)
  76 {
  77    if (x < 0.0f)
  78       return 0;
  79    else if (x > 1.0f)
  80       return MAX_UINT(dst_bits);
  81    else
  82       return F_TO_I(x * MAX_UINT(dst_bits));
  83 }
  84
  85 static inline unsigned
  86 _mesa_half_to_unorm(uint16_t x, unsigned dst_bits)
  87 {
  88    return _mesa_float_to_unorm(_mesa_half_to_float(x), dst_bits);
  89 }
  90
  91 static inline unsigned
  92 _mesa_unorm_to_unorm(unsigned x, unsigned src_bits, unsigned dst_bits)
  93 {
  94    if (src_bits < dst_bits)
  95       return EXTEND_NORMALIZED_INT(x, src_bits, dst_bits);
  96    else
  97       return x >> (src_bits - dst_bits);
  98 }
  99
 100 static inline unsigned
 101 _mesa_snorm_to_unorm(int x, unsigned src_bits, unsigned dst_bits)
 102 {
 103    if (x < 0)
 104       return 0;
 105    else
 106       return _mesa_unorm_to_unorm(x, src_bits - 1, dst_bits);
 107 }
 108
 109 static inline int
 110 _mesa_float_to_snorm(float x, unsigned dst_bits)
 111 {
 112    if (x < -1.0f)
 113       return -MAX_INT(dst_bits);
 114    else if (x > 1.0f)
 115       return MAX_INT(dst_bits);
 116    else
 117       return F_TO_I(x * MAX_INT(dst_bits));
 118 }
 119
 120 static inline int
 121 _mesa_half_to_snorm(uint16_t x, unsigned dst_bits)
 122 {
 123    return _mesa_float_to_snorm(_mesa_half_to_float(x), dst_bits);
 124 }
 125
 126 static inline int
 127 _mesa_unorm_to_snorm(unsigned x, unsigned src_bits, unsigned dst_bits)
 128 {
 129    return _mesa_unorm_to_unorm(x, src_bits, dst_bits - 1);
 130 }
 131
 132 static inline int
 133 _mesa_snorm_to_snorm(int x, unsigned src_bits, unsigned dst_bits)
 134 {
 135    if (x < -MAX_INT(src_bits))
 136       return -MAX_INT(dst_bits);
 137    else if (src_bits < dst_bits)
 138       return EXTEND_NORMALIZED_INT(x, src_bits - 1, dst_bits - 1);
 139    else
 140       return x >> (src_bits - dst_bits);
 141 }
 142
 143 static inline unsigned
 144 _mesa_unsigned_to_unsigned(unsigned src, unsigned dst_size)
 145 {
 146    return MIN2(src, MAX_UINT(dst_size));
 147 }
 148
 149 static inline int
 150 _mesa_unsigned_to_signed(unsigned src, unsigned dst_size)
 151 {
 152    return MIN2(src, MAX_INT(dst_size));
 153 }
 154
 155 static inline int
 156 _mesa_signed_to_signed(int src, unsigned dst_size)
 157 {
 158    return CLAMP(src, MIN_INT(dst_size), MAX_INT(dst_size));
 159 }
 160
 161 static inline unsigned
 162 _mesa_signed_to_unsigned(int src, unsigned dst_size)
 163 {
 164    return CLAMP(src, 0, MAX_UINT(dst_size));
 165 }
 166
 167 static inline unsigned
 168 _mesa_float_to_unsigned(float src, unsigned dst_bits)
 169 {
 170    if (src < 0.0f)
 171       return 0;
 172    if (src > (float)MAX_UINT(dst_bits))
 173        return MAX_UINT(dst_bits);
 174    return _mesa_signed_to_unsigned(src, dst_bits);
 175 }
 176
 177 static inline unsigned
 178 _mesa_float_to_signed(float src, unsigned dst_bits)
 179 {
 180    if (src < (float)(-MAX_INT(dst_bits)))
 181       return -MAX_INT(dst_bits);
 182    if (src > (float)MAX_INT(dst_bits))
 183        return MAX_INT(dst_bits);
 184    return _mesa_signed_to_signed(src, dst_bits);
 185 }
 186
 187 static inline unsigned
 188 _mesa_half_to_unsigned(uint16_t src, unsigned dst_bits)
 189 {
 190    if (_mesa_half_is_negative(src))
 191       return 0;
 192    return _mesa_unsigned_to_unsigned(_mesa_float_to_half(src), dst_bits);
 193 }
 194
 195 static inline unsigned
 196 _mesa_half_to_signed(uint16_t src, unsigned dst_bits)
 197 {
 198    return _mesa_float_to_signed(_mesa_half_to_float(src), dst_bits);
 199 }
 200
 201 bool
 202 _mesa_format_to_array(mesa_format, GLenum *type, int *num_components,
 203                       uint8_t swizzle[4], bool *normalized);
 204
 205 void
 206 _mesa_swizzle_and_convert(void *dst, GLenum dst_type, int num_dst_channels,
 207                           const void *src, GLenum src_type, int num_src_channels,
 208                           const uint8_t swizzle[4], bool normalized, int count);
 209
 210 #endif