opencv/3rdparty/openexr/IlmImf/ImfEnvmap.cpp
2012-10-17 15:32:23 +04:00

329 lines
7.2 KiB
C++

///////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2004, Industrial Light & Magic, a division of Lucas
// Digital Ltd. LLC
//
// 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.
// * Neither the name of Industrial Light & Magic nor the names of
// its contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER 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 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 DAMAGE.
//
///////////////////////////////////////////////////////////////////////////
//-----------------------------------------------------------------------------
//
// Environment maps
//
//-----------------------------------------------------------------------------
#include <ImfEnvmap.h>
#include "ImathFun.h"
#include <algorithm>
#include <math.h>
using namespace std;
using namespace Imath;
namespace Imf {
namespace LatLongMap {
V2f
latLong (const V3f &dir)
{
float r = sqrt (dir.z * dir.z + dir.x * dir.x);
float latitude = (r < abs (dir.y))?
acos (r / dir.length()) * sign (dir.y):
asin (dir.y / dir.length());
float longitude = (dir.z == 0 && dir.x == 0)? 0: atan2 (dir.x, dir.z);
return V2f (latitude, longitude);
}
V2f
latLong (const Box2i &dataWindow, const V2f &pixelPosition)
{
float latitude, longitude;
if (dataWindow.max.y > dataWindow.min.y)
{
latitude = -M_PI *
((pixelPosition.y - dataWindow.min.y) /
(dataWindow.max.y - dataWindow.min.y) - 0.5f);
}
else
{
latitude = 0;
}
if (dataWindow.max.x > dataWindow.min.x)
{
longitude = -2 * M_PI *
((pixelPosition.x - dataWindow.min.x) /
(dataWindow.max.x - dataWindow.min.x) - 0.5f);
}
else
{
longitude = 0;
}
return V2f (latitude, longitude);
}
V2f
pixelPosition (const Box2i &dataWindow, const V2f &latLong)
{
float x = latLong.y / (-2 * M_PI) + 0.5f;
float y = latLong.x / -M_PI + 0.5f;
return V2f (x * (dataWindow.max.x - dataWindow.min.x) + dataWindow.min.x,
y * (dataWindow.max.y - dataWindow.min.y) + dataWindow.min.y);
}
V2f
pixelPosition (const Box2i &dataWindow, const V3f &direction)
{
return pixelPosition (dataWindow, latLong (direction));
}
V3f
direction (const Box2i &dataWindow, const V2f &pixelPosition)
{
V2f ll = latLong (dataWindow, pixelPosition);
return V3f (sin (ll.y) * cos (ll.x),
sin (ll.x),
cos (ll.y) * cos (ll.x));
}
} // namespace LatLongMap
namespace CubeMap {
int
sizeOfFace (const Box2i &dataWindow)
{
return min ((dataWindow.max.x - dataWindow.min.x + 1),
(dataWindow.max.y - dataWindow.min.y + 1) / 6);
}
Box2i
dataWindowForFace (CubeMapFace face, const Box2i &dataWindow)
{
int sof = sizeOfFace (dataWindow);
Box2i dwf;
dwf.min.x = 0;
dwf.min.y = int (face) * sof;
dwf.max.x = dwf.min.x + sof - 1;
dwf.max.y = dwf.min.y + sof - 1;
return dwf;
}
V2f
pixelPosition (CubeMapFace face, const Box2i &dataWindow, V2f positionInFace)
{
Box2i dwf = dataWindowForFace (face, dataWindow);
V2f pos (0, 0);
switch (face)
{
case CUBEFACE_POS_X:
pos.x = dwf.min.x + positionInFace.y;
pos.y = dwf.max.y - positionInFace.x;
break;
case CUBEFACE_NEG_X:
pos.x = dwf.max.x - positionInFace.y;
pos.y = dwf.max.y - positionInFace.x;
break;
case CUBEFACE_POS_Y:
pos.x = dwf.min.x + positionInFace.x;
pos.y = dwf.max.y - positionInFace.y;
break;
case CUBEFACE_NEG_Y:
pos.x = dwf.min.x + positionInFace.x;
pos.y = dwf.min.y + positionInFace.y;
break;
case CUBEFACE_POS_Z:
pos.x = dwf.max.x - positionInFace.x;
pos.y = dwf.max.y - positionInFace.y;
break;
case CUBEFACE_NEG_Z:
pos.x = dwf.min.x + positionInFace.x;
pos.y = dwf.max.y - positionInFace.y;
break;
}
return pos;
}
void
faceAndPixelPosition (const V3f &direction,
const Box2i &dataWindow,
CubeMapFace &face,
V2f &pif)
{
int sof = sizeOfFace (dataWindow);
float absx = abs (direction.x);
float absy = abs (direction.y);
float absz = abs (direction.z);
if (absx >= absy && absx >= absz)
{
if (absx == 0)
{
//
// Special case - direction is (0, 0, 0)
//
face = CUBEFACE_POS_X;
pif = V2f (0, 0);
return;
}
pif.x = (direction.y / absx + 1) / 2 * (sof - 1);
pif.y = (direction.z / absx + 1) / 2 * (sof - 1);
if (direction.x > 0)
face = CUBEFACE_POS_X;
else
face = CUBEFACE_NEG_X;
}
else if (absy >= absz)
{
pif.x = (direction.x / absy + 1) / 2 * (sof - 1);
pif.y = (direction.z / absy + 1) / 2 * (sof - 1);
if (direction.y > 0)
face = CUBEFACE_POS_Y;
else
face = CUBEFACE_NEG_Y;
}
else
{
pif.x = (direction.x / absz + 1) / 2 * (sof - 1);
pif.y = (direction.y / absz + 1) / 2 * (sof - 1);
if (direction.z > 0)
face = CUBEFACE_POS_Z;
else
face = CUBEFACE_NEG_Z;
}
}
V3f
direction (CubeMapFace face, const Box2i &dataWindow, const V2f &positionInFace)
{
int sof = sizeOfFace (dataWindow);
V2f pos;
if (sof > 1)
{
pos = V2f (positionInFace.x / (sof - 1) * 2 - 1,
positionInFace.y / (sof - 1) * 2 - 1);
}
else
{
pos = V2f (0, 0);
}
V3f dir (1, 0, 0);
switch (face)
{
case CUBEFACE_POS_X:
dir.x = 1;
dir.y = pos.x;
dir.z = pos.y;
break;
case CUBEFACE_NEG_X:
dir.x = -1;
dir.y = pos.x;
dir.z = pos.y;
break;
case CUBEFACE_POS_Y:
dir.x = pos.x;
dir.y = 1;
dir.z = pos.y;
break;
case CUBEFACE_NEG_Y:
dir.x = pos.x;
dir.y = -1;
dir.z = pos.y;
break;
case CUBEFACE_POS_Z:
dir.x = pos.x;
dir.y = pos.y;
dir.z = 1;
break;
case CUBEFACE_NEG_Z:
dir.x = pos.x;
dir.y = pos.y;
dir.z = -1;
break;
}
return dir;
}
} // namespace CubeMap
} // namespace Imf