Ptex
PtexHalf.h
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1#ifndef PtexHalf_h
2#define PtexHalf_h
3
4/*
5PTEX SOFTWARE
6Copyright 2014 Disney Enterprises, Inc. All rights reserved
7
8Redistribution and use in source and binary forms, with or without
9modification, are permitted provided that the following conditions are
10met:
11
12 * Redistributions of source code must retain the above copyright
13 notice, this list of conditions and the following disclaimer.
14
15 * Redistributions in binary form must reproduce the above copyright
16 notice, this list of conditions and the following disclaimer in
17 the documentation and/or other materials provided with the
18 distribution.
19
20 * The names "Disney", "Walt Disney Pictures", "Walt Disney Animation
21 Studios" or the names of its contributors may NOT be used to
22 endorse or promote products derived from this software without
23 specific prior written permission from Walt Disney Pictures.
24
25Disclaimer: THIS SOFTWARE IS PROVIDED BY WALT DISNEY PICTURES AND
26CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
27BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
28FOR A PARTICULAR PURPOSE, NONINFRINGEMENT AND TITLE ARE DISCLAIMED.
29IN NO EVENT SHALL WALT DISNEY PICTURES, THE COPYRIGHT HOLDER OR
30CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
31EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
32PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
33PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND BASED ON ANY
34THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
36OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
37*/
38
44#ifndef PTEXAPI
45# if defined(_WIN32) || defined(_WINDOWS) || defined(_MSC_VER)
46# ifndef PTEX_STATIC
47# ifdef PTEX_EXPORTS
48# define PTEXAPI __declspec(dllexport)
49# else
50# define PTEXAPI __declspec(dllimport)
51# endif
52# else
53# define PTEXAPI
54# endif
55# else
56# define PTEXAPI
57# endif
58#endif
59
60#include "PtexInt.h"
61
62#include "PtexVersion.h"
63
65
88struct PtexHalf {
89 uint16_t bits;
90
93 PtexHalf(float val) : bits(fromFloat(val)) {}
94 PtexHalf(double val) : bits(fromFloat(float(val))) {}
95 operator float() const { return toFloat(bits); }
96 PtexHalf& operator=(float val) { bits = fromFloat(val); return *this; }
97
98 static float toFloat(uint16_t h)
99 {
100 union { uint32_t i; float f; } u;
101 u.i = h2fTable[h];
102 return u.f;
103 }
104
105 static uint16_t fromFloat(float val)
106 {
107 if (val==0) return 0;
108 union { uint32_t i; float f; } u;
109 u.f = val;
110 int e = f2hTable[(u.i>>23)&0x1ff];
111 if (e) return (uint16_t)(e + (((u.i&0x7fffff) + 0x1000) >> 13));
112 return fromFloat_except(u.i);
113 }
114
115 private:
116 PTEXAPI static uint16_t fromFloat_except(uint32_t val);
117#ifndef DOXYGEN
118 /* internal */ public:
119#endif
120 PTEXAPI static uint32_t h2fTable[65536];
121 PTEXAPI static uint16_t f2hTable[512];
122};
123
125
126using Ptex::PtexHalf;
127
128#endif
#define PTEXAPI
Definition: PtexHalf.h:56
Portable fixed-width integer types.
#define PTEX_NAMESPACE_END
Definition: PtexVersion.h:62
Half-precision (16-bit) floating-point type.
Definition: PtexHalf.h:88
PtexHalf & operator=(float val)
Definition: PtexHalf.h:96
uint16_t bits
Definition: PtexHalf.h:89
PtexHalf()
Default constructor, value is undefined.
Definition: PtexHalf.h:92
static uint16_t fromFloat(float val)
Definition: PtexHalf.h:105
PtexHalf(double val)
Definition: PtexHalf.h:94
static uint32_t h2fTable[65536]
Definition: PtexHalf.h:120
static uint16_t fromFloat_except(uint32_t val)
Handle exceptional cases for half-to-float conversion.
Definition: PtexHalf.cpp:44
static uint16_t f2hTable[512]
Definition: PtexHalf.h:121
static float toFloat(uint16_t h)
Definition: PtexHalf.h:98
PtexHalf(float val)
Definition: PtexHalf.h:93