Ptex: PtexHalf.h Source File

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#include "PtexExports.h"
45#include "PtexInt.h"
46#include "PtexVersion.h"
47
48 PTEX_NAMESPACE_BEGIN
49
72 struct PtexHalf {
73 uint16_t bits;
74
76 PtexHalf() {}
77 PtexHalf(float val) : bits(fromFloat(val)) {}
78 PtexHalf(double val) : bits(fromFloat(float(val))) {}
79 operator float() const { return toFloat(bits); }
80 PtexHalf& operator=(float val) { bits = fromFloat(val); return *this; }
81
82 static float toFloat(uint16_t h)
83 {
84 union { uint32_t i; float f; } u;
85 u.i = h2fTable[h];
86 return u.f;
87 }
88
89 static uint16_t fromFloat(float val)
90 {
91 if (val==0) return 0;
92 union { uint32_t i; float f; } u;
93 u.f = val;
94 int e = f2hTable[(u.i>>23)&0x1ff];
95 if (e) return (uint16_t)(e + (((u.i&0x7fffff) + 0x1000) >> 13));
96 return fromFloat_except(u.i);
97 }
98
99 private:
100 PTEXAPI static uint16_t fromFloat_except(uint32_t val);
101#ifndef DOXYGEN
102 /* internal */ public:
103#endif
104 PTEXAPI static uint32_t h2fTable[65536];
105 PTEXAPI static uint16_t f2hTable[512];
106};
107
108 PTEX_NAMESPACE_END
109
110using Ptex::PtexHalf;
111
112#endif
PtexExports.h
Definitions related to exported Ptex API symbol visibility.
PTEXAPI
#define PTEXAPI
Definition: PtexExports.h:60
PtexInt.h
Portable fixed-width integer types.
PtexVersion.h
PTEX_NAMESPACE_END
#define PTEX_NAMESPACE_END
Definition: PtexVersion.h:62
PTEX_NAMESPACE_BEGIN
Definition: PtexSeparableKernel.cpp:42
PtexHalf
Half-precision (16-bit) floating-point type.
Definition: PtexHalf.h:72
PtexHalf::operator=
PtexHalf & operator=(float val)
Definition: PtexHalf.h:80
PtexHalf::bits
uint16_t bits
Definition: PtexHalf.h:73
PtexHalf::PtexHalf
PtexHalf()
Default constructor, value is undefined.
Definition: PtexHalf.h:76
PtexHalf::fromFloat
static uint16_t fromFloat(float val)
Definition: PtexHalf.h:89
PtexHalf::PtexHalf
PtexHalf(double val)
Definition: PtexHalf.h:78
PtexHalf::h2fTable
static uint32_t h2fTable[65536]
Definition: PtexHalf.h:104
PtexHalf::fromFloat_except
static uint16_t fromFloat_except(uint32_t val)
Handle exceptional cases for half-to-float conversion.
Definition: PtexHalf.cpp:44
PtexHalf::f2hTable
static uint16_t f2hTable[512]
Definition: PtexHalf.h:105
PtexHalf::toFloat
static float toFloat(uint16_t h)
Definition: PtexHalf.h:82
PtexHalf::PtexHalf
PtexHalf(float val)
Definition: PtexHalf.h:77