PtexSeparableKernel.h
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#ifndef PtexSeparableKernel_h
#define PtexSeparableKernel_h
/*
PTEX SOFTWARE
Copyright 2014 Disney Enterprises, Inc. All rights reserved
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the
distribution.
* The names "Disney", "Walt Disney Pictures", "Walt Disney Animation
Studios" or the names of its contributors may NOT be used to
endorse or promote products derived from this software without
specific prior written permission from Walt Disney Pictures.
Disclaimer: THIS SOFTWARE IS PROVIDED BY WALT DISNEY PICTURES AND
CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE, NONINFRINGEMENT AND TITLE ARE DISCLAIMED.
IN NO EVENT SHALL WALT DISNEY PICTURES, THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND BASED ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*/
#include <assert.h>
#include <algorithm>
#include <numeric>
#include "Ptexture.h"
#include "PtexUtils.h"
PTEX_NAMESPACE_BEGIN
// Separable convolution kernel
class PtexSeparableKernel {
public:
Res res; // resolution that kernel was built for
int u, v; // uv offset within face data
int uw, vw; // kernel width
float* ku; // kernel weights in u
float* kv; // kernel weights in v
static const int kmax = 10; // max kernel width
float kubuff[kmax];
float kvbuff[kmax];
int rot;
PtexSeparableKernel()
: res(0), u(0), v(0), uw(0), vw(0), ku(kubuff), kv(kvbuff), rot(0)
{
kubuff[0] = 0; // keep cppcheck happy
kvbuff[0] = 0;
}
PtexSeparableKernel(const PtexSeparableKernel& k)
{
set(k.res, k.u, k.v, k.uw, k.vw, k.ku, k.kv, k.rot);
}
PtexSeparableKernel& operator= (const PtexSeparableKernel& k)
{
set(k.res, k.u, k.v, k.uw, k.vw, k.ku, k.kv, k.rot);
return *this;
}
void set(Res resVal,
int uVal, int vVal,
int uwVal, int vwVal,
const float* kuVal, const float* kvVal, int rotVal=0)
{
assert(uwVal <= kmax && vwVal <= kmax);
res = resVal;
u = uVal;
v = vVal;
uw = uwVal;
vw = vwVal;
memcpy(kubuff, kuVal, sizeof(*ku)*uw);
memcpy(kvbuff, kvVal, sizeof(*kv)*vw);
ku = kubuff;
kv = kvbuff;
rot = rotVal;
}
void stripZeros()
{
while (ku[0] == 0) { ku++; u++; uw--; }
while (ku[uw-1] == 0) { uw--; }
while (kv[0] == 0) { kv++; v++; vw--; }
while (kv[vw-1] == 0) { vw--; }
assert(uw > 0 && vw > 0);
}
float weight() const
{
return accumulate(ku, uw) * accumulate(kv, vw);
}
void mergeL(BorderMode mode)
{
int w = -u;
if (mode != m_black)
ku[w] += accumulate(ku, w);
ku += w;
uw -= w;
u = 0;
}
void mergeR(BorderMode mode)
{
int w = uw + u - res.u();
float* kp = ku + uw - w;
if (mode != m_black)
kp[-1] += accumulate(kp, w);
uw -= w;
}
void mergeB(BorderMode mode)
{
int w = -v;
if (mode != m_black)
kv[w] += accumulate(kv, w);
kv += w;
vw -= w;
v = 0;
}
void mergeT(BorderMode mode)
{
int w = vw + v - res.v();
float* kp = kv + vw - w;
if (mode != m_black)
kp[-1] += accumulate(kp, w);
vw -= w;
}
void splitL(PtexSeparableKernel& k)
{
// split off left piece of width w into k
int w = -u;
if (w < uw) {
// normal case - split off a portion
// res u v uw vw ku kv
k.set(res, res.u()-w, v, w, vw, ku, kv);
// update local
u = 0;
uw -= w;
ku += w;
}
else {
// entire kernel is split off
k = *this;
k.u += res.u();
u = 0; uw = 0;
}
}
void splitR(PtexSeparableKernel& k)
{
// split off right piece of width w into k
int w = u + uw - res.u();
if (w < uw) {
// normal case - split off a portion
// res u v uw vw ku kv
k.set(res, 0, v, w, vw, ku + uw - w, kv);
// update local
uw -= w;
}
else {
// entire kernel is split off
k = *this;
k.u -= res.u();
u = 0; uw = 0;
}
}
void splitB(PtexSeparableKernel& k)
{
// split off bottom piece of width w into k
int w = -v;
if (w < vw) {
// normal case - split off a portion
// res u v uw vw ku kv
k.set(res, u, res.v()-w, uw, w, ku, kv);
// update local
v = 0;
vw -= w;
kv += w;
}
else {
// entire kernel is split off
k = *this;
k.v += res.v();
v = 0; vw = 0;
}
}
void splitT(PtexSeparableKernel& k)
{
// split off top piece of width w into k
int w = v + vw - res.v();
if (w < vw) {
// normal case - split off a portion
// res u v uw vw ku kv
k.set(res, u, 0, uw, w, ku, kv + vw - w);
// update local
vw -= w;
}
else {
// entire kernel is split off
k = *this;
k.v -= res.v();
v = 0; vw = 0;
}
}
void flipU()
{
u = res.u() - u - uw;
std::reverse(ku, ku+uw);
}
void flipV()
{
v = res.v() - v - vw;
std::reverse(kv, kv+vw);
}
void swapUV()
{
res.swapuv();
std::swap(u, v);
std::swap(uw, vw);
std::swap(ku, kv);
}
void rotate(int rotVal)
{
// rotate kernel 'rot' steps ccw
switch (rotVal & 3) {
default: return;
case 1: flipU(); swapUV(); break;
case 2: flipU(); flipV(); break;
case 3: flipV(); swapUV(); break;
}
rot = (rot + rotVal)&3;
}
bool adjustMainToSubface(int eid)
{
// to adjust the kernel for the subface, we must adjust the res down and offset the uv coords
// however, if the res is already zero, we must upres the kernel first
if (res.ulog2 == 0) upresU();
if (res.vlog2 == 0) upresV();
if (res.ulog2 > 0) res.ulog2--;
if (res.vlog2 > 0) res.vlog2--;
// offset uv coords and determine whether target subface is the primary one
bool primary = 0;
int resu = res.u(), resv = res.v();
switch (eid&3) {
case e_bottom:
primary = (u < resu);
v -= resv;
if (!primary) u -= resu;
break;
case e_right:
primary = (v < resv);
if (!primary) v -= resv;
break;
case e_top:
primary = (u >= resu);
if (primary) u -= resu;
break;
case e_left:
primary = (v >= resv);
u -= resu;
if (primary) v -= resv;
break;
}
return primary;
}
void adjustSubfaceToMain(int eid)
{
switch (eid&3) {
case e_bottom: v += res.v(); break;
case e_right: break;
case e_top: u += res.u(); break;
case e_left: u += res.u(); v += res.v(); break;
}
res.ulog2++; res.vlog2++;
}
void downresU()
{
float* src = ku;
float* dst = ku;
// skip odd leading sample (if any)
if (u & 1) {
dst++;
src++;
uw--;
}
// combine even pairs
for (int i = uw/2; i > 0; i--) {
*dst++ = src[0] + src[1];
src += 2;
}
// copy odd trailing sample (if any)
if (uw & 1) {
*dst++ = *src++;
}
// update state
u /= 2;
uw = int(dst - ku);
res.ulog2--;
}
void downresV()
{
float* src = kv;
float* dst = kv;
// skip odd leading sample (if any)
if (v & 1) {
dst++;
src++;
vw--;
}
// combine even pairs
for (int i = vw/2; i > 0; i--) {
*dst++ = src[0] + src[1];
src += 2;
}
// copy odd trailing sample (if any)
if (vw & 1) {
*dst++ = *src++;
}
// update state
v /= 2;
vw = int(dst - kv);
res.vlog2--;
}
void upresU()
{
float* src = ku + uw-1;
float* dst = ku + uw*2-2;
for (int i = uw; i > 0; i--) {
dst[0] = dst[1] = *src-- / 2;
dst -=2;
}
uw *= 2;
u *= 2;
res.ulog2++;
}
void upresV()
{
float* src = kv + vw-1;
float* dst = kv + vw*2-2;
for (int i = vw; i > 0; i--) {
dst[0] = dst[1] = *src-- / 2;
dst -=2;
}
vw *= 2;
v *= 2;
res.vlog2++;
}
float makeSymmetric(float initialWeight)
{
assert(u == 0 && v == 0);
// downres higher-res dimension until equal
if (res.ulog2 > res.vlog2) {
do { downresU(); } while(res.ulog2 > res.vlog2);
}
else if (res.vlog2 > res.ulog2) {
do { downresV(); } while (res.vlog2 > res.ulog2);
}
// truncate excess samples in longer dimension
uw = vw = PtexUtils::min(uw, vw);
// combine corresponding u and v samples and compute new kernel weight
float newWeight = 0;
for (int i = 0; i < uw; i++) {
float sum = ku[i] + kv[i];
ku[i] = kv[i] = sum;
newWeight += sum;
}
newWeight *= newWeight; // equivalent to k.weight() ( = sum(ku)*sum(kv) )
// compute scale factor to compensate for weight change
float scale = newWeight == 0 ? 1.f : initialWeight / newWeight;
// Note: a sharpening kernel (like Mitchell) can produce
// negative weights which may cancel out when adding the two
// kernel axes together, and this can cause the compensation
// scale factor to spike up. We expect the scale factor to be
// less than one in "normal" cases (i.e. ku*kv <= (ku+kv)^2 if ku
// and kv are both positive), so clamping to -1..1 will have
// no effect on positive kernels. If there are negative
// weights, the clamping will just limit the amount of
// sharpening happening at the corners, and the result will
// still be smooth.
// clamp scale factor to -1..1 range
if (scale >= 1) {
// scale by 1 (i.e. do nothing)
}
else {
if (scale < -1) {
// a negative scale means the original kernel had an overall negative weight
// after making symmetric, the kernel will always be positive
// scale ku by -1
// note: choice of u is arbitrary; we could have scaled u or v (but not both)
for (int i = 0; i < uw; i++) ku[i] *= -1;
newWeight = -newWeight;
}
else {
// scale ku to restore initialWeight (again, choice of u instead of v is arbitrary)
for (int i = 0; i < uw; i++) ku[i] *= scale;
newWeight = initialWeight;
}
}
return newWeight;
}
void apply(float* dst, void* data, DataType dt, int nChan, int nTxChan)
{
// dispatch specialized apply function
ApplyFn fn = applyFunctions[(nChan!=nTxChan)*20 + ((unsigned)nChan<=4)*nChan*4 + dt];
fn(*this, dst, data, nChan, nTxChan);
}
void applyConst(float* dst, void* data, DataType dt, int nChan)
{
PtexUtils::applyConst(weight(), dst, data, dt, nChan);
}
private:
typedef void (*ApplyFn)(PtexSeparableKernel& k, float* dst, void* data, int nChan, int nTxChan);
typedef void (*ApplyConstFn)(float weight, float* dst, void* data, int nChan);
static ApplyFn applyFunctions[40];
static ApplyConstFn applyConstFunctions[20];
static inline float accumulate(const float* p, int n)
{
float result = 0;
for (const float* e = p + n; p != e; p++) result += *p;
return result;
}
};
PTEX_NAMESPACE_END
#endif
PtexUtils.h
PTEX_NAMESPACE_END
#define PTEX_NAMESPACE_END
Definition PtexVersion.h:62
Ptexture.h
Public API classes for reading, writing, caching, and filtering Ptex files.
PtexSeparableKernel
Definition PtexSeparableKernel.h:48
PtexSeparableKernel::mergeT
void mergeT(BorderMode mode)
Definition PtexSeparableKernel.h:139
PtexSeparableKernel::mergeB
void mergeB(BorderMode mode)
Definition PtexSeparableKernel.h:129
PtexSeparableKernel::stripZeros
void stripZeros()
Definition PtexSeparableKernel.h:96
PtexSeparableKernel::apply
void apply(float *dst, void *data, DataType dt, int nChan, int nTxChan)
Definition PtexSeparableKernel.h:457
PtexSeparableKernel::kubuff
float kubuff[kmax]
Definition PtexSeparableKernel.h:56
PtexSeparableKernel::makeSymmetric
float makeSymmetric(float initialWeight)
Definition PtexSeparableKernel.h:397
PtexSeparableKernel::flipU
void flipU()
Definition PtexSeparableKernel.h:234
PtexSeparableKernel::PtexSeparableKernel
PtexSeparableKernel()
Definition PtexSeparableKernel.h:60
PtexSeparableKernel::u
int u
Definition PtexSeparableKernel.h:51
PtexSeparableKernel::ApplyConstFn
void(* ApplyConstFn)(float weight, float *dst, void *data, int nChan)
Definition PtexSeparableKernel.h:471
PtexSeparableKernel::kv
float * kv
Definition PtexSeparableKernel.h:54
PtexSeparableKernel::set
void set(Res resVal, int uVal, int vVal, int uwVal, int vwVal, const float *kuVal, const float *kvVal, int rotVal=0)
Definition PtexSeparableKernel.h:78
PtexSeparableKernel::splitT
void splitT(PtexSeparableKernel &k)
Definition PtexSeparableKernel.h:214
PtexSeparableKernel::rot
int rot
Definition PtexSeparableKernel.h:58
PtexSeparableKernel::res
Res res
Definition PtexSeparableKernel.h:50
PtexSeparableKernel::adjustSubfaceToMain
void adjustSubfaceToMain(int eid)
Definition PtexSeparableKernel.h:302
PtexSeparableKernel::splitB
void splitB(PtexSeparableKernel &k)
Definition PtexSeparableKernel.h:192
PtexSeparableKernel::PtexSeparableKernel
PtexSeparableKernel(const PtexSeparableKernel &k)
Definition PtexSeparableKernel.h:67
PtexSeparableKernel::kvbuff
float kvbuff[kmax]
Definition PtexSeparableKernel.h:57
PtexSeparableKernel::ApplyFn
void(* ApplyFn)(PtexSeparableKernel &k, float *dst, void *data, int nChan, int nTxChan)
Definition PtexSeparableKernel.h:470
PtexSeparableKernel::applyConstFunctions
static ApplyConstFn applyConstFunctions[20]
Definition PtexSeparableKernel.h:473
PtexSeparableKernel::applyFunctions
static ApplyFn applyFunctions[40]
Definition PtexSeparableKernel.h:137
PtexSeparableKernel::vw
int vw
Definition PtexSeparableKernel.h:52
PtexSeparableKernel::v
int v
Definition PtexSeparableKernel.h:51
PtexSeparableKernel::operator=
PtexSeparableKernel & operator=(const PtexSeparableKernel &k)
Definition PtexSeparableKernel.h:72
PtexSeparableKernel::splitL
void splitL(PtexSeparableKernel &k)
Definition PtexSeparableKernel.h:148
PtexSeparableKernel::flipV
void flipV()
Definition PtexSeparableKernel.h:240
PtexSeparableKernel::downresV
void downresV()
Definition PtexSeparableKernel.h:342
PtexSeparableKernel::ku
float * ku
Definition PtexSeparableKernel.h:53
PtexSeparableKernel::uw
int uw
Definition PtexSeparableKernel.h:52
PtexSeparableKernel::mergeR
void mergeR(BorderMode mode)
Definition PtexSeparableKernel.h:120
PtexSeparableKernel::applyConst
void applyConst(float *dst, void *data, DataType dt, int nChan)
Definition PtexSeparableKernel.h:464
PtexSeparableKernel::adjustMainToSubface
bool adjustMainToSubface(int eid)
Definition PtexSeparableKernel.h:266
PtexSeparableKernel::mergeL
void mergeL(BorderMode mode)
Definition PtexSeparableKernel.h:110
PtexSeparableKernel::upresV
void upresV()
Definition PtexSeparableKernel.h:384
PtexSeparableKernel::upresU
void upresU()
Definition PtexSeparableKernel.h:371
PtexSeparableKernel::splitR
void splitR(PtexSeparableKernel &k)
Definition PtexSeparableKernel.h:171
PtexSeparableKernel::kmax
static const int kmax
Definition PtexSeparableKernel.h:55
PtexSeparableKernel::rotate
void rotate(int rotVal)
Definition PtexSeparableKernel.h:254
PtexSeparableKernel::accumulate
static float accumulate(const float *p, int n)
Definition PtexSeparableKernel.h:474
PtexSeparableKernel::swapUV
void swapUV()
Definition PtexSeparableKernel.h:246
PtexSeparableKernel::weight
float weight() const
Definition PtexSeparableKernel.h:105
PtexSeparableKernel::downresU
void downresU()
Definition PtexSeparableKernel.h:313
PTEX_NAMESPACE_BEGIN
Definition PtexSeparableKernel.cpp:42
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