Cloned library of VTK-5.0.0 with extra build files for internal package management.
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/*=========================================================================
Program: Visualization Toolkit
Module: $RCSfile: vtkUnstructuredGridPartialPreIntegration.cxx,v $
Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
All rights reserved.
See Copyright.txt or http://www.kitware.com/Copyright.htm for details.
This software is distributed WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the above copyright notice for more information.
=========================================================================*/
/*
* Copyright 2004 Sandia Corporation.
* Under the terms of Contract DE-AC04-94AL85000, there is a non-exclusive
* license for use of this work by or on behalf of the
* U.S. Government. Redistribution and use in source and binary forms, with
* or without modification, are permitted provided that this Notice and any
* statement of authorship are reproduced on all copies.
*/
#include "vtkUnstructuredGridPartialPreIntegration.h"
#include "vtkObjectFactory.h"
#include "vtkVolumeProperty.h"
#include "vtkVolume.h"
#include "vtkDoubleArray.h"
#include "vtkPiecewiseFunction.h"
#include "vtkColorTransferFunction.h"
#include "vtkUnstructuredGridLinearRayIntegrator.h"
#include "vtkMath.h"
#include <vtkstd/vector>
#include <vtkstd/set>
#include <vtkstd/algorithm>
//-----------------------------------------------------------------------------
// VTK's native classes for defining transfer functions is actually slow to
// access, so we have to cache it somehow. This class is straightforward
// copy of the transfer function.
class vtkPartialPreIntegrationTransferFunction
{
public:
void GetTransferFunction(vtkColorTransferFunction *color,
vtkPiecewiseFunction *opacity,
double unit_distance,
double scalar_range[2]);
void GetTransferFunction(vtkPiecewiseFunction *intensity,
vtkPiecewiseFunction *opacity,
double unit_distance,
double scalar_range[2]);
inline void GetColor(double x, double c[4]);
struct acolor {
double c[4];
};
vtkstd::vector<double> ControlPoints;
vtkstd::vector<acolor> Colors;
};
static const double huebends[6] = {
1.0/6.0, 1.0/3.0, 0.5, 2.0/3.0, 5.0/6.0, 1.0
};
void vtkPartialPreIntegrationTransferFunction::GetTransferFunction(
vtkColorTransferFunction *color,
vtkPiecewiseFunction *opacity,
double unit_distance,
double scalar_range[2])
{
vtkstd::set<double> cpset;
double *function_range = color->GetRange();
double *function = color->GetDataPointer();
if( !function )
{
return;
}
while (1)
{
cpset.insert(function[0]);
if (function[0] == function_range[1]) break;
function += 4;
}
if (color->GetColorSpace() != VTK_CTF_RGB)
{
// If we are in an HSV color space, we must insert control points
// in places where the RGB bends.
double rgb[3], hsv[3];
double hue1, hue2;
double x1, x2;
vtkstd::set<double>::iterator i = cpset.begin();
x1 = *i;
color->GetColor(x1, rgb);
vtkMath::RGBToHSV(rgb, hsv);
hue1 = hsv[0];
for (i++; i != cpset.end(); i++)
{
x2 = *i;
color->GetColor(x2, rgb);
vtkMath::RGBToHSV(rgb, hsv);
hue2 = hsv[0];
// Are we crossing the 0/1 boundary?
if ( (color->GetColorSpace() == VTK_CTF_HSV && color->GetHSVWrap() )
&& ((hue1 - hue2 > 0.5) || (hue2 - hue1 > 0.5)) )
{
// Yes, we are crossing the boundary.
if (hue1 > hue2)
{
int j;
for (j = 0; huebends[j] <= hue2; j++)
{
double interp = (1-hue1+huebends[j])/(1-hue1+hue2);
cpset.insert((x2-x1)*interp + x1);
}
while (huebends[j] < hue1) j++;
for ( ; j < 6; j++)
{
double interp = (huebends[j]-hue1)/(1-hue1+hue2);
cpset.insert((x2-x1)*interp + x1);
}
}
else
{
int j;
for (j = 0; huebends[j] <= hue1; j++)
{
double interp = (hue1-huebends[j])/(1-hue2+hue1);
cpset.insert((x2-x1)*interp + x1);
}
while (huebends[j] < hue2) j++;
for ( ; j < 6; j++)
{
double interp = (1-huebends[j]+hue1)/(1-hue2+hue1);
cpset.insert((x2-x1)*interp + x1);
}
}
}
else
{
// No, we are not crossing the boundary.
int j = 0;
double minh, maxh;
if (hue1 < hue2)
{
minh = hue1; maxh = hue2;
}
else
{
minh = hue2; maxh = hue1;
}
while (huebends[j] < minh) j++;
for ( ; huebends[j] < maxh; j++)
{
double interp = (huebends[j]-hue1)/(hue2-hue1);
cpset.insert((x2-x1)*interp + x1);
}
}
x1 = x2;
hue1 = hue2;
}
}
function_range = opacity->GetRange();
function = opacity->GetDataPointer();
while (1)
{
cpset.insert(function[0]);
if (function[0] == function_range[0]) break;
function += 2;
}
// Add the scalar at the beginning and end of the range so the interpolation
// is correct there.
cpset.insert(scalar_range[0]);
cpset.insert(scalar_range[1]);
// Make extra sure there are at least two entries in cpset.
if (cpset.size() < 2)
{
cpset.insert(0.0);
cpset.insert(1.0);
}
// Now record control points and colors.
this->ControlPoints.erase(this->ControlPoints.begin(),
this->ControlPoints.end());
this->ControlPoints.resize(cpset.size());
this->Colors.erase(this->Colors.begin(), this->Colors.end());
this->Colors.resize(cpset.size());
vtkstd::copy(cpset.begin(), cpset.end(), this->ControlPoints.begin());
for (unsigned int i = 0; i < this->ControlPoints.size(); i++)
{
color->GetColor(this->ControlPoints[i], this->Colors[i].c);
this->Colors[i].c[3] = ( opacity->GetValue(this->ControlPoints[i])
/ unit_distance);
}
}
void vtkPartialPreIntegrationTransferFunction::GetTransferFunction(
vtkPiecewiseFunction *intensity,
vtkPiecewiseFunction *opacity,
double unit_distance,
double scalar_range[2])
{
vtkstd::set<double> cpset;
double *function_range = intensity->GetRange();
double *function = intensity->GetDataPointer();
while (1)
{
cpset.insert(function[0]);
if (function[0] == function_range[1]) break;
function += 2;
}
function_range = opacity->GetRange();
function = opacity->GetDataPointer();
while (1)
{
cpset.insert(function[0]);
if (function[0] == function_range[0]) break;
function += 2;
}
// Add the scalar at the beginning and end of the range so the interpolation
// is correct there.
cpset.insert(scalar_range[0]);
cpset.insert(scalar_range[1]);
// Make extra sure there are at least two entries in cpset.
if (cpset.size() < 2)
{
cpset.insert(0.0);
cpset.insert(1.0);
}
// Now record control points and colors.
this->ControlPoints.erase(this->ControlPoints.begin(),
this->ControlPoints.end());
this->ControlPoints.resize(cpset.size());
this->Colors.erase(this->Colors.begin(), this->Colors.end());
this->Colors.resize(cpset.size());
vtkstd::copy(cpset.begin(), cpset.end(), this->ControlPoints.begin());
for (unsigned int i = 0; i < this->ControlPoints.size(); i++)
{
// Is setting all the colors to the same value the right thing to do?
this->Colors[i].c[0] = this->Colors[i].c[1] = this->Colors[i].c[2]
= intensity->GetValue(this->ControlPoints[i]);
this->Colors[i].c[3] = ( opacity->GetValue(this->ControlPoints[i])
/ unit_distance);
}
}
inline void vtkPartialPreIntegrationTransferFunction::GetColor(double x,
double c[4])
{
unsigned int i = 1;
unsigned int size = this->ControlPoints.size();
if( !size )
{
return;
}
while (this->ControlPoints[i] < x && i < size-1)
{
i++;
}
double before = this->ControlPoints[i-1];
double after = this->ControlPoints[i];
double interp = (x-before)/(after-before);
double *beforec = this->Colors[i-1].c;
double *afterc = this->Colors[i].c;
c[0] = (1-interp)*beforec[0] + interp*afterc[0];
c[1] = (1-interp)*beforec[1] + interp*afterc[1];
c[2] = (1-interp)*beforec[2] + interp*afterc[2];
c[3] = (1-interp)*beforec[3] + interp*afterc[3];
}
//-----------------------------------------------------------------------------
vtkCxxRevisionMacro(vtkUnstructuredGridPartialPreIntegration, "$Revision: 1.4 $");
vtkStandardNewMacro(vtkUnstructuredGridPartialPreIntegration);
float vtkUnstructuredGridPartialPreIntegration::PsiTable[PSI_TABLE_SIZE*PSI_TABLE_SIZE];
int vtkUnstructuredGridPartialPreIntegration::PsiTableBuilt = 0;
//-----------------------------------------------------------------------------
vtkUnstructuredGridPartialPreIntegration::vtkUnstructuredGridPartialPreIntegration()
{
this->Property = NULL;
this->TransferFunctions = NULL;
this->NumIndependentComponents = 0;
}
//-----------------------------------------------------------------------------
vtkUnstructuredGridPartialPreIntegration::~vtkUnstructuredGridPartialPreIntegration()
{
if (this->TransferFunctions)
{
delete[] this->TransferFunctions;
}
}
//-----------------------------------------------------------------------------
void vtkUnstructuredGridPartialPreIntegration::PrintSelf(ostream &os,
vtkIndent indent)
{
this->Superclass::PrintSelf(os, indent);
}
//-----------------------------------------------------------------------------
void vtkUnstructuredGridPartialPreIntegration::Initialize(
vtkVolume *volume,
vtkDataArray *scalars)
{
vtkVolumeProperty *property = volume->GetProperty();
if ( (property == this->Property)
&& (this->TransferFunctionsModified > property->GetMTime()) )
{
// Nothing has changed from the last time Initialize was run.
return;
}
this->BuildPsiTable();
int numcomponents = scalars->GetNumberOfComponents();
this->Property = property;
this->TransferFunctionsModified.Modified();
if (!property->GetIndependentComponents())
{
// The scalars actually hold material properties.
if ((numcomponents != 4) && (numcomponents != 2) )
{
vtkErrorMacro("Only 2-tuples and 4-tuples allowed for dependent components.");
}
return;
}
if (this->TransferFunctions)
{
delete[] this->TransferFunctions;
}
this->NumIndependentComponents = numcomponents;
this->TransferFunctions
= new vtkPartialPreIntegrationTransferFunction[numcomponents];
for (int component = 0; component < numcomponents; component++)
{
if (property->GetColorChannels(component) == 1)
{
this->TransferFunctions[component]
.GetTransferFunction(property->GetGrayTransferFunction(component),
property->GetScalarOpacity(component),
property->GetScalarOpacityUnitDistance(component),
scalars->GetRange(component));
}
else
{
this->TransferFunctions[component]
.GetTransferFunction(property->GetRGBTransferFunction(component),
property->GetScalarOpacity(component),
property->GetScalarOpacityUnitDistance(component),
scalars->GetRange(component));
}
}
}
//-----------------------------------------------------------------------------
void vtkUnstructuredGridPartialPreIntegration::Integrate(
vtkDoubleArray *intersectionLengths,
vtkDataArray *nearIntersections,
vtkDataArray *farIntersections,
float color[4])
{
int numintersections = intersectionLengths->GetNumberOfTuples();
if (this->Property->GetIndependentComponents())
{
int numscalars = nearIntersections->GetNumberOfComponents();
double *nearScalars = new double[numscalars];
double *farScalars = new double[numscalars];
vtkstd::set<double> segments;
for (vtkIdType i = 0; i < numintersections; i++)
{
double total_length = intersectionLengths->GetValue(i);
nearIntersections->GetTuple(i, nearScalars);
farIntersections->GetTuple(i, farScalars);
// Split up segment on control points, because it is nonlinear in
// these regions.
segments.erase(segments.begin(), segments.end());
segments.insert(0.0);
segments.insert(1.0);
for (int j = 0; j < numscalars; j++)
{
vtkstd::vector<double> &cp = this->TransferFunctions[j].ControlPoints;
vtkIdType numcp = cp.size();
double minscalar, maxscalar;
if (nearScalars[j] < farScalars[j])
{
minscalar = nearScalars[j]; maxscalar = farScalars[j];
}
else
{
minscalar = farScalars[j]; maxscalar = nearScalars[j];
}
for (int k = 0; k < numcp; k++)
{
if (cp[k] <= minscalar) continue;
if (cp[k] >= maxscalar) break;
// If we are here, we need to break the segment at the given scalar.
// Find the fraction between the near and far segment points.
segments.insert( (cp[k]-nearScalars[j])
/ (farScalars[j]-nearScalars[j]));
}
}
// Iterate over all the segment pieces (from front to back) and
// integrate each piece.
vtkstd::set<double>::iterator segi = segments.begin();
double nearInterpolant = *segi;
for (segi++; segi != segments.end(); segi++)
{
double farInterpolant = *segi;
double nearcolor[4] = {0.0, 0.0, 0.0, 0.0};
double farcolor[4] = {0.0, 0.0, 0.0, 0.0};
double length = total_length*(farInterpolant-nearInterpolant);
// Here we handle the mixing of material properties. This never
// seems to be defined very clearly. I handle this by assuming
// that each scalar represents a cloud of particles of a certian
// color and a certain density. We mix the scalars in the same way
// as mixing these particles together. By necessity, the density
// becomes greater. The "opacity" parameter is really interpreted
// as the attenuation coefficient (which is proportional to
// density) and can therefore easily be greater than one. The
// opacity of the resulting color will, however, always be scaled
// between 0 and 1.
for (int j = 0; j < numscalars; j++)
{
double scalar
= (farScalars[j]-nearScalars[j])*nearInterpolant + nearScalars[j];
if (j == 0)
{
this->TransferFunctions[j].GetColor(scalar, nearcolor);
}
else
{
double c[4];
this->TransferFunctions[j].GetColor(scalar, c);
if (c[3] + nearcolor[3] > 1.0e-8f)
{
nearcolor[0] *= nearcolor[3]/(c[3] + nearcolor[3]);
nearcolor[1] *= nearcolor[3]/(c[3] + nearcolor[3]);
nearcolor[2] *= nearcolor[3]/(c[3] + nearcolor[3]);
nearcolor[0] += c[0]*c[3]/(c[3] + nearcolor[3]);
nearcolor[1] += c[1]*c[3]/(c[3] + nearcolor[3]);
nearcolor[2] += c[2]*c[3]/(c[3] + nearcolor[3]);
nearcolor[3] += c[3];
}
}
scalar
= (farScalars[j]-nearScalars[j])*farInterpolant + nearScalars[j];
if (j == 0)
{
this->TransferFunctions[j].GetColor(scalar, farcolor);
}
else
{
double c[4];
this->TransferFunctions[j].GetColor(scalar, c);
if (c[3] + farcolor[3] > 1.0e-8f)
{
farcolor[0] *= farcolor[3]/(c[3] + farcolor[3]);
farcolor[1] *= farcolor[3]/(c[3] + farcolor[3]);
farcolor[2] *= farcolor[3]/(c[3] + farcolor[3]);
farcolor[0] += c[0]*c[3]/(c[3] + farcolor[3]);
farcolor[1] += c[1]*c[3]/(c[3] + farcolor[3]);
farcolor[2] += c[2]*c[3]/(c[3] + farcolor[3]);
farcolor[3] += c[3];
}
}
}
this->IntegrateRay(length, nearcolor, nearcolor[3],
farcolor, farcolor[3], color);
nearInterpolant = farInterpolant;
}
}
delete[] nearScalars;
delete[] farScalars;
}
else
{
double unitdistance = this->Property->GetScalarOpacityUnitDistance();
if (nearIntersections->GetNumberOfComponents() == 4)
{
for (vtkIdType i = 0; i < numintersections; i++)
{
double length = intersectionLengths->GetValue(i);
double *nearcolor = nearIntersections->GetTuple(i);
double *farcolor = farIntersections->GetTuple(i);
this->IntegrateRay(length, nearcolor, nearcolor[3]/unitdistance,
farcolor, farcolor[3]/unitdistance, color);
}
}
else // Two components.
{
for (vtkIdType i = 0; i < numintersections; i++)
{
double length = intersectionLengths->GetValue(i);
double *nearcolor = nearIntersections->GetTuple(i);
double *farcolor = farIntersections->GetTuple(i);
this->IntegrateRay(length, nearcolor[0], nearcolor[1]/unitdistance,
farcolor[0], farcolor[1]/unitdistance, color);
}
}
}
}
//-----------------------------------------------------------------------------
void vtkUnstructuredGridPartialPreIntegration::BuildPsiTable()
{
if (vtkUnstructuredGridPartialPreIntegration::PsiTableBuilt)
{
return;
}
for (int gammafi = 0; gammafi < PSI_TABLE_SIZE; gammafi++)
{
float gammaf = ((float)gammafi+0.0f)/PSI_TABLE_SIZE;
float taufD = gammaf/(1-gammaf);
for (int gammabi = 0; gammabi < PSI_TABLE_SIZE; gammabi++)
{
float gammab = ((float)gammabi+0.0f)/PSI_TABLE_SIZE;
float taubD = gammab/(1-gammab);
PsiTable[gammafi*PSI_TABLE_SIZE + gammabi]
= vtkUnstructuredGridLinearRayIntegrator::Psi(1, taufD, taubD);
}
}
vtkUnstructuredGridPartialPreIntegration::PsiTableBuilt = 1;
}