Ptex

PtexTriangleKernel.cpp
Go to the documentation of this file.
1/*
2 PTEX SOFTWARE
3 Copyright 2014 Disney Enterprises, Inc. All rights reserved
4
5 Redistribution and use in source and binary forms, with or without
6 modification, are permitted provided that the following conditions are
7 met:
8
9 * Redistributions of source code must retain the above copyright
10 notice, this list of conditions and the following disclaimer.
11
12 * Redistributions in binary form must reproduce the above copyright
13 notice, this list of conditions and the following disclaimer in
14 the documentation and/or other materials provided with the
15 distribution.
16
17 * The names "Disney", "Walt Disney Pictures", "Walt Disney Animation
18 Studios" or the names of its contributors may NOT be used to
19 endorse or promote products derived from this software without
20 specific prior written permission from Walt Disney Pictures.
21
22 Disclaimer: THIS SOFTWARE IS PROVIDED BY WALT DISNEY PICTURES AND
23 CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
24 BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
25 FOR A PARTICULAR PURPOSE, NONINFRINGEMENT AND TITLE ARE DISCLAIMED.
26 IN NO EVENT SHALL WALT DISNEY PICTURES, THE COPYRIGHT HOLDER OR
27 CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
28 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
29 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND BASED ON ANY
31 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
33 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
34*/
35
36#include "PtexPlatform.h"
37#include "PtexUtils.h"
38#include "PtexHalf.h"
39#include "PtexTriangleKernel.h"
40
41 PTEX_NAMESPACE_BEGIN
42
43 namespace {
44 inline float gaussian(float x_squared)
45 {
46 static const float scale = -0.5f * (PtexTriangleKernelWidth * PtexTriangleKernelWidth);
47 return (float)exp(scale * x_squared);
48 }
49
50 // apply to 1..4 channels (unrolled channel loop) of packed data (nTxChan==nChan)
51 // the ellipse equation, Q, is calculated via finite differences (Heckbert '89 pg 57)
52 template<class T, int nChan>
53 void Apply(PtexTriangleKernelIter& k, float* result, void* data, int /*nChan*/, int /*nTxChan*/)
54 {
55 int nTxChan = nChan;
56 float DDQ = 2.0f*k.A;
57 for (int vi = k.v1; vi != k.v2; vi++) {
58 int xw = k.rowlen - vi;
59 int x1 = PtexUtils::max(k.u1, xw-k.w2);
60 int x2 = PtexUtils::min(k.u2, xw-k.w1);
61 float U = (float)x1 - k.u;
62 float V = (float)vi - k.v;
63 float DQ = k.A*(2.0f*U+1.0f)+k.B*V;
64 float Q = k.A*U*U + (k.B*U + k.C*V)*V;
65 T* p = static_cast<T*>(data) + (vi * k.rowlen + x1) * nTxChan;
66 T* pEnd = p + (x2-x1)*nTxChan;
67 for (; p < pEnd; p += nTxChan) {
68 if (Q < 1.0f) {
69 float weight = gaussian(Q)*k.wscale;
70 k.weight += weight;
71 PtexUtils::VecAccum<T,nChan>()(result, p, weight);
72 }
73 Q += DQ;
74 DQ += DDQ;
75 }
76 }
77 }
78
79 // apply to 1..4 channels (unrolled channel loop) w/ pixel stride
80 template<class T, int nChan>
81 void ApplyS(PtexTriangleKernelIter& k, float* result, void* data, int /*nChan*/, int nTxChan)
82 {
83 float DDQ = 2.0f*k.A;
84 for (int vi = k.v1; vi != k.v2; vi++) {
85 int xw = k.rowlen - vi;
86 int x1 = PtexUtils::max(k.u1, xw-k.w2);
87 int x2 = PtexUtils::min(k.u2, xw-k.w1);
88 float U = (float)x1 - k.u;
89 float V = (float)vi - k.v;
90 float DQ = k.A*(2.0f*U+1.0f)+k.B*V;
91 float Q = k.A*U*U + (k.B*U + k.C*V)*V;
92 T* p = static_cast<T*>(data) + (vi * k.rowlen + x1) * nTxChan;
93 T* pEnd = p + (x2-x1)*nTxChan;
94 for (; p < pEnd; p += nTxChan) {
95 if (Q < 1.0f) {
96 float weight = gaussian(Q)*k.wscale;
97 k.weight += weight;
98 PtexUtils::VecAccum<T,nChan>()(result, p, weight);
99 }
100 Q += DQ;
101 DQ += DDQ;
102 }
103 }
104 }
105
106 // apply to N channels (general case)
107 template<class T>
108 void ApplyN(PtexTriangleKernelIter& k, float* result, void* data, int nChan, int nTxChan)
109 {
110 float DDQ = 2.0f*k.A;
111 for (int vi = k.v1; vi != k.v2; vi++) {
112 int xw = k.rowlen - vi;
113 int x1 = PtexUtils::max(k.u1, xw-k.w2);
114 int x2 = PtexUtils::min(k.u2, xw-k.w1);
115 float U = (float)x1 - k.u;
116 float V = (float)vi - k.v;
117 float DQ = k.A*(2.0f*U+1.0f)+k.B*V;
118 float Q = k.A*U*U + (k.B*U + k.C*V)*V;
119 T* p = static_cast<T*>(data) + (vi * k.rowlen + x1) * nTxChan;
120 T* pEnd = p + (x2-x1)*nTxChan;
121 for (; p < pEnd; p += nTxChan) {
122 if (Q < 1.0f) {
123 float weight = gaussian(Q)*k.wscale;
124 k.weight += weight;
125 PtexUtils::VecAccumN<T>()(result, p, nChan, weight);
126 }
127 Q += DQ;
128 DQ += DDQ;
129 }
130 }
131 }
132}
133
134
135 PtexTriangleKernelIter::ApplyFn
136 PtexTriangleKernelIter::applyFunctions[] = {
137 // nChan == nTxChan
138 ApplyN<uint8_t>, ApplyN<uint16_t>, ApplyN<PtexHalf>, ApplyN<float>,
139 Apply<uint8_t,1>, Apply<uint16_t,1>, Apply<PtexHalf,1>, Apply<float,1>,
140 Apply<uint8_t,2>, Apply<uint16_t,2>, Apply<PtexHalf,2>, Apply<float,2>,
141 Apply<uint8_t,3>, Apply<uint16_t,3>, Apply<PtexHalf,3>, Apply<float,3>,
142 Apply<uint8_t,4>, Apply<uint16_t,4>, Apply<PtexHalf,4>, Apply<float,4>,
143
144 // nChan != nTxChan (need pixel stride)
145 ApplyN<uint8_t>, ApplyN<uint16_t>, ApplyN<PtexHalf>, ApplyN<float>,
146 ApplyS<uint8_t,1>, ApplyS<uint16_t,1>, ApplyS<PtexHalf,1>, ApplyS<float,1>,
147 ApplyS<uint8_t,2>, ApplyS<uint16_t,2>, ApplyS<PtexHalf,2>, ApplyS<float,2>,
148 ApplyS<uint8_t,3>, ApplyS<uint16_t,3>, ApplyS<PtexHalf,3>, ApplyS<float,3>,
149 ApplyS<uint8_t,4>, ApplyS<uint16_t,4>, ApplyS<PtexHalf,4>, ApplyS<float,4>,
150};
151
152
153 void PtexTriangleKernelIter::applyConst(float* dst, void* data, DataType dt, int nChan)
154{
155 // iterate over texel locations and calculate weight as if texture weren't const
156 float DDQ = 2.0f*A;
157 for (int vi = v1; vi != v2; vi++) {
158 int xw = rowlen - vi;
159 int x1 = PtexUtils::max(u1, xw-w2);
160 int x2 = PtexUtils::min(u2, xw-w1);
161 float U = (float)x1 - u;
162 float V = (float)vi - v;
163 float DQ = A*(2.0f*U+1.0f)+B*V;
164 float Q = A*U*U + (B*U + C*V)*V;
165 for (int x = x1; x < x2; x++) {
166 if (Q < 1.0f) {
167 weight += gaussian(Q)*wscale;
168 }
169 Q += DQ;
170 DQ += DDQ;
171 }
172 }
173
174 // apply weight to single texel value
175 PtexUtils::applyConst(weight, dst, data, dt, nChan);
176}
177
178 PTEX_NAMESPACE_END
PtexHalf.h
Half-precision floating-point type.
PtexPlatform.h
Platform-specific classes, functions, and includes.
PtexTriangleKernel.h
PtexTriangleKernelWidth
PTEX_NAMESPACE_BEGIN const float PtexTriangleKernelWidth
Definition PtexTriangleKernel.h:50
PtexUtils.h
PTEX_NAMESPACE_END
#define PTEX_NAMESPACE_END
Definition PtexVersion.h:62
PtexTriangleKernelIter
Triangle filter kernel iterator (in texel coords)
Definition PtexTriangleKernel.h:54
PtexTriangleKernelIter::A
float A
Definition PtexTriangleKernel.h:60
PtexTriangleKernelIter::v1
int v1
Definition PtexTriangleKernel.h:58
PtexTriangleKernelIter::applyFunctions
static ApplyFn applyFunctions[40]
Definition PtexTriangleKernel.h:136
PtexTriangleKernelIter::ApplyFn
void(* ApplyFn)(PtexTriangleKernelIter &k, float *dst, void *data, int nChan, int nTxChan)
Definition PtexTriangleKernel.h:76
PtexTriangleKernelIter::v2
int v2
Definition PtexTriangleKernel.h:59
PtexTriangleKernelIter::rowlen
int rowlen
Definition PtexTriangleKernel.h:56
PtexTriangleKernelIter::w1
int w1
Definition PtexTriangleKernel.h:58
PtexTriangleKernelIter::u
float u
Definition PtexTriangleKernel.h:57
PtexTriangleKernelIter::C
float C
Definition PtexTriangleKernel.h:60
PtexTriangleKernelIter::w2
int w2
Definition PtexTriangleKernel.h:59
PtexTriangleKernelIter::u1
int u1
Definition PtexTriangleKernel.h:58
PtexTriangleKernelIter::weight
float weight
Definition PtexTriangleKernel.h:63
PtexTriangleKernelIter::u2
int u2
Definition PtexTriangleKernel.h:59
PtexTriangleKernelIter::applyConst
void applyConst(float *dst, void *data, DataType dt, int nChan)
Definition PtexTriangleKernel.cpp:153
PtexTriangleKernelIter::v
float v
Definition PtexTriangleKernel.h:57
PtexTriangleKernelIter::B
float B
Definition PtexTriangleKernel.h:60
PtexTriangleKernelIter::wscale
float wscale
Definition PtexTriangleKernel.h:62
PTEX_NAMESPACE_BEGIN
Definition PtexSeparableKernel.cpp:42
PTEX_NAMESPACE_BEGIN::gaussian
float gaussian(float x_squared)
Definition PtexTriangleKernel.cpp:44
PTEX_NAMESPACE_BEGIN::ApplyN
void ApplyN(PtexSeparableKernel &k, float *result, void *data, int nChan, int nTxChan)
Definition PtexSeparableKernel.cpp:105
PTEX_NAMESPACE_BEGIN::ApplyS
void ApplyS(PtexSeparableKernel &k, float *result, void *data, int, int nTxChan)
Definition PtexSeparableKernel.cpp:75
PTEX_NAMESPACE_BEGIN::Apply
void Apply(PtexSeparableKernel &k, float *result, void *data, int, int)
Definition PtexSeparableKernel.cpp:45
PtexUtils::applyConst
void applyConst(float weight, float *dst, void *data, Ptex::DataType dt, int nChan)
Definition PtexUtils.h:279
PtexUtils::min
T min(T a, T b)
Definition PtexUtils.h:148
PtexUtils::max
T max(T a, T b)
Definition PtexUtils.h:151
PtexUtils::VecAccumN
Definition PtexUtils.h:247
PtexUtils::VecAccum
Definition PtexUtils.h:233