src/mesa/main/colormac.h

   1 /* $Id: colormac.h,v 1.4 2000/11/24 10:25:05 keithw Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.5
   6  *
   7  * Copyright (C) 1999-2000  Brian Paul   All Rights Reserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included
  17  * in all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  23  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  24  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  */
  26
  27
  28
  29 /*
  30  * Color-related macros
  31  */
  32
  33 #ifndef COLORMAC_H
  34 #define COLORMAC_H
  35
  36
  37 #include "glheader.h"
  38 #include "config.h"
  39 #include "macros.h"
  40 #include "mmath.h"
  41 /* Do not reference mtypes.h from this file.
  42  */
  43
  44
  45 /*
  46  * Integer / float conversion for colors, normals, etc.
  47  */
  48
  49 #define BYTE_TO_UBYTE(b)   (b < 0 ? 0 : (GLubyte) b)
  50 #define SHORT_TO_UBYTE(s)  (s < 0 ? 0 : (GLubyte) (s >> 7))
  51 #define USHORT_TO_UBYTE(s)              (GLubyte) (s >> 8)
  52 #define INT_TO_UBYTE(i)    (i < 0 ? 0 : (GLubyte) (i >> 23))
  53 #define UINT_TO_UBYTE(i)                (GLubyte) (i >> 24)
  54
  55 /* Convert GLfloat in [0.0,1.0] to GLubyte in [0,255] */
  56 #define FLOAT_TO_UBYTE(X)       ((GLubyte) (GLint) (((X)) * 255.0F))
  57
  58
  59 /* Convert GLbyte in [-128,127] to GLfloat in [-1.0,1.0] */
  60 #define BYTE_TO_FLOAT(B)        ((2.0F * (B) + 1.0F) * (1.0F/255.0F))
  61
  62 /* Convert GLfloat in [-1.0,1.0] to GLbyte in [-128,127] */
  63 #define FLOAT_TO_BYTE(X)        ( (((GLint) (255.0F * (X))) - 1) / 2 )
  64
  65
  66 /* Convert GLushort in [0,65536] to GLfloat in [0.0,1.0] */
  67 #define USHORT_TO_FLOAT(S)      ((GLfloat) (S) * (1.0F / 65535.0F))
  68
  69 /* Convert GLfloat in [0.0,1.0] to GLushort in [0,65536] */
  70 #define FLOAT_TO_USHORT(X)      ((GLushort) (GLint) ((X) * 65535.0F))
  71
  72
  73 /* Convert GLshort in [-32768,32767] to GLfloat in [-1.0,1.0] */
  74 #define SHORT_TO_FLOAT(S)       ((2.0F * (S) + 1.0F) * (1.0F/65535.0F))
  75
  76 /* Convert GLfloat in [0.0,1.0] to GLshort in [-32768,32767] */
  77 #define FLOAT_TO_SHORT(X)       ( (((GLint) (65535.0F * (X))) - 1) / 2 )
  78
  79
  80 /* Convert GLuint in [0,4294967295] to GLfloat in [0.0,1.0] */
  81 #define UINT_TO_FLOAT(U)        ((GLfloat) (U) * (1.0F / 4294967295.0F))
  82
  83 /* Convert GLfloat in [0.0,1.0] to GLuint in [0,4294967295] */
  84 #define FLOAT_TO_UINT(X)        ((GLuint) ((X) * 4294967295.0))
  85
  86
  87 /* Convert GLint in [-2147483648,2147483647] to GLfloat in [-1.0,1.0] */
  88 #define INT_TO_FLOAT(I)         ((2.0F * (I) + 1.0F) * (1.0F/4294967294.0F))
  89
  90 /* Convert GLfloat in [-1.0,1.0] to GLint in [-2147483648,2147483647] */
  91 /* causes overflow:
  92 #define FLOAT_TO_INT(X)         ( (((GLint) (4294967294.0F * (X))) - 1) / 2 )
  93 */
  94 /* a close approximation: */
  95 #define FLOAT_TO_INT(X)         ( (GLint) (2147483647.0 * (X)) )
  96
  97
  98
  99 #if CHAN_BITS == 8
 100
 101 #define BYTE_TO_CHAN(b)   ((b) < 0 ? 0 : (GLchan) (b))
 102 #define UBYTE_TO_CHAN(b)  (b)
 103 #define SHORT_TO_CHAN(s)  ((s) < 0 ? 0 : (GLchan) ((s) >> 7))
 104 #define USHORT_TO_CHAN(s) ((GLchan) ((s) >> 8))
 105 #define INT_TO_CHAN(i)    ((i) < 0 ? 0 : (GLchan) ((i) >> 23))
 106 #define UINT_TO_CHAN(i)   ((GLchan) ((i) >> 24))
 107
 108 #define CHAN_TO_FLOAT(c)  UBYTE_TO_FLOAT(c)
 109
 110 #define FLOAT_COLOR_TO_CHAN(c, f) FLOAT_COLOR_TO_UBYTE_COLOR(c, f)
 111
 112 #define COPY_CHAN4(DST, SRC)  COPY_4UBV(DST, SRC)
 113
 114 #define CHAN_PRODUCT(a, b)  ( (GLubyte) (((GLint)(a) * ((GLint)(b) + 1)) >> 8) )
 115
 116 #elif CHAN_BITS == 16
 117
 118 #define BYTE_TO_CHAN(b)   ((b) < 0 ? 0 : (GLchan) ((b) * 516))
 119 #define UBYTE_TO_CHAN(b)  ((GLchan) (((b) << 8) | (b)))
 120 #define SHORT_TO_CHAN(s)  ((s) < 0 ? 0 : (GLchan) (s))
 121 #define USHORT_TO_CHAN(s) (s)
 122 #define INT_TO_CHAN(i)    ((i) < 0 ? 0 : (GLchan) ((i) >> 15))
 123 #define UINT_TO_CHAN(i)   ((GLchan) ((i) >> 16))
 124
 125 #define CHAN_TO_FLOAT(c)  ((GLfloat) ((c) * (1.0 / CHAN_MAXF)))
 126
 127 #define FLOAT_COLOR_TO_CHAN(c, f) \
 128         c = ((GLchan) FloatToInt(CLAMP(f, 0.0F, 1.0F) * CHAN_MAXF + 0.5F))
 129
 130 #define COPY_CHAN4(DST, SRC)  COPY_4V(DST, SRC)
 131
 132 #define CHAN_PRODUCT(a, b)  ( (GLchan) ((((GLint) (a)) * ((GLint) (b))) / 65535) )
 133
 134 #elif CHAN_BITS == 32
 135
 136 /* XXX floating-point color channels not fully thought-out */
 137 #define BYTE_TO_CHAN(b)   ((GLfloat) ((b) * (1.0F / 127.0F)))
 138 #define UBYTE_TO_CHAN(b)  ((GLfloat) ((b) * (1.0F / 255.0F)))
 139 #define SHORT_TO_CHAN(s)  ((GLfloat) ((s) * (1.0F / 32767.0F)))
 140 #define USHORT_TO_CHAN(s) ((GLfloat) ((s) * (1.0F / 65535.0F)))
 141 #define INT_TO_CHAN(i)    ((GLfloat) ((i) * (1.0F / 2147483647.0F)))
 142 #define UINT_TO_CHAN(i)   ((GLfloat) ((i) * (1.0F / 4294967295.0F)))
 143
 144 #define CHAN_TO_FLOAT(c)  (c)
 145
 146 #define FLOAT_COLOR_TO_CHAN(c, f)  c = f
 147
 148 #define COPY_CHAN4(DST, SRC)  COPY_4V(DST, SRC)
 149
 150 #define CHAN_PRODUCT(a, b)    ((a) * (b))
 151
 152 #else
 153
 154 #error unexpected CHAN_BITS size
 155
 156 #endif
 157
 158
 159 #define FLOAT_RGB_TO_CHAN_RGB(dst, f)           \
 160 do {                                            \
 161    FLOAT_COLOR_TO_CHAN(dst[0], f[0]);           \
 162    FLOAT_COLOR_TO_CHAN(dst[1], f[1]);           \
 163    FLOAT_COLOR_TO_CHAN(dst[2], f[2]);           \
 164 } while(0)
 165
 166 #define FLOAT_RGBA_TO_CHAN_RGBA(c, f)           \
 167 do {                                            \
 168    FLOAT_COLOR_TO_CHAN(c[0], f[0]);             \
 169    FLOAT_COLOR_TO_CHAN(c[1], f[1]);             \
 170    FLOAT_COLOR_TO_CHAN(c[2], f[2]);             \
 171    FLOAT_COLOR_TO_CHAN(c[3], f[3]);             \
 172 } while(0)
 173
 174
 175 #if CHAN_BITS == 32
 176
 177 #define FLOAT_TO_CHAN(f)   (f)
 178 #define DOUBLE_TO_CHAN(f)  ((GLfloat) (f))
 179 #define UNCLAMPED_FLOAT_TO_CHAN(f)   (f)
 180 #define UNCLAMPED_DOUBLE_TO_CHAN(f)  ((GLfloat) (f))
 181
 182 #else
 183
 184 #define FLOAT_TO_CHAN(f)   ( (GLchan) FloatToInt((f) * CHAN_MAXF + 0.5F) )
 185 #define DOUBLE_TO_CHAN(f)  ( (GLchan) FloatToInt((f) * CHAN_MAXF + 0.5F) )
 186
 187 #define UNCLAMPED_FLOAT_TO_CHAN(f)   \
 188    ( (GLchan) FloatToInt( CLAMP(f, 0.0, 1.0) * CHAN_MAXF + 0.5F) )
 189
 190 #define UNCLAMPED_DOUBLE_TO_CHAN(f)  \
 191    ( (GLchan) FloatToInt( CLAMP(f, 0.0, 1.0) * CHAN_MAXF + 0.5F) )
 192
 193 #endif
 194
 195
 196 #endif /* COLORMAC_H */