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/*=========================================================================
Program: Visualization Toolkit
Module: TestPolyhedron5.cxx
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.
=========================================================================*/
#include "vtkClipDataSet.h"
#include "vtkContourFilter.h"
#include "vtkDoubleArray.h"
#include "vtkNew.h"
#include "vtkPointData.h"
#include "vtkPoints.h"
#include "vtkUnstructuredGrid.h"
#include "vtkXMLPolyDataWriter.h"
/* This is the layout of a cube with points on each edge
In the test below we're going to test all combinations of
edge points being present. As there are 12 edge points, the
number of combinations is 2^12, i.e. 4096 cases. This can be
calculated in ~15 seconds
Point indices: Face indices:
7--14--6 *------*
| | | |
19 18 | 2 |
| | | |
7--19--3--10--2--18--6 *------*------*------*
| | | | | | | |
15 11 9 13 | 3 | 4 | 1 |
| | | | | | | |
4--16--0---8--1--17--5 *------*------*------*
| | | |
16 17 | 0 |
| | | |
4--12--5 *------*
| | | |
15 13 | 5 |
| | | |
7--14--6 *------*
*/
#define CORNERS 8
#define EDGES 12
#define FACES 6
#define NPOINTS (CORNERS + EDGES + FACES)
const int Faces[FACES][8] = {
{ 0, 8, 1, 17, 5, 12, 4, 16 },
{ 1, 9, 2, 18, 6, 13, 5, 17 },
{ 2, 10, 3, 19, 7, 14, 6, 18 },
{ 3, 11, 0, 16, 4, 15, 7, 19 },
{ 0, 8, 1, 9, 2, 10, 3, 11 },
{ 4, 12, 5, 13, 6, 14, 7, 15 },
};
const double Points[CORNERS + EDGES + FACES][3] = {
// first the corner points
// lower plane
{ 0, 0, 0 },
{ 0, 2, 0 },
{ 2, 2, 0 },
{ 2, 0, 0 },
// upper plane
{ 0, 0, 2 },
{ 0, 2, 2 },
{ 2, 2, 2 },
{ 2, 0, 2 },
// then the edge points
// lower plane
{ 0, 1, 0 },
{ 1, 2, 0 },
{ 2, 1, 0 },
{ 1, 0, 0 },
// upper plane
{ 0, 1, 2 },
{ 1, 2, 2 },
{ 2, 1, 2 },
{ 1, 0, 2 },
// intermediate plane
// make the polyhedron concave by offsetting
// these points towards the cube center
{ 0.25, 0.25, 1 },
{ 0.25, 1.75, 1 },
{ 1.75, 1.75, 1 },
{ 1.75, 0.25, 1 },
// face centers (not used for now)
{ 1, 1, 0 },
{ 0, 1, 1 },
{ 1, 2, 1 },
{ 2, 1, 1 },
{ 1, 0, 1 },
{ 1, 1, 2 },
};
void BuildCaseGrid(int aCase, vtkUnstructuredGrid* grid, vtkIdList* faceStream)
{
faceStream->Reset();
for (int i = 0; i < FACES; ++i)
{
const int* face = Faces[i];
int nFacePoints = 0;
for (int j = 0; j < 8; ++j)
{
int idx = 1 << face[j];
if ((aCase & idx) != 0)
{
++nFacePoints;
}
}
faceStream->InsertNextId(nFacePoints);
for (int j = 0; j < 8; ++j)
{
int idx = 1 << face[j];
if ((aCase & idx) != 0)
{
faceStream->InsertNextId(face[j]);
}
}
}
grid->InsertNextCell(VTK_POLYHEDRON, FACES, faceStream->GetPointer(0));
}
void BuildPoints(vtkPoints* pts)
{
for (int i = 0; i < NPOINTS; ++i)
{
const double* pt = Points[i];
pts->InsertNextPoint(pt);
}
}
int TestPolyhedronCombinatorialContouring(int vtkNotUsed(argc), char* vtkNotUsed(argv)[])
{
vtkNew<vtkPoints> pts;
BuildPoints(pts);
vtkNew<vtkUnstructuredGrid> g;
g->Allocate(1);
vtkNew<vtkIdList> ptIds;
vtkNew<vtkXMLPolyDataWriter> pw;
vtkNew<vtkDoubleArray> data;
data->SetName("AirVolumeFraction");
data->Allocate(NPOINTS);
data->SetNumberOfTuples(NPOINTS);
// assign 0 to even points and 1 to odd points, then contour at 0.5
// TODO: also vary the data systematically?
// (although that would give rise to sum(i=1..20, binomial(20,i)*2^(6+i)) = O(10^7) cases
// and 4,096 cases run in about 15 seconds)
// FOR NOW: don't vary the data
for (int i = 0; i < NPOINTS; ++i)
{
data->SetTuple1(i, i % 2);
}
g->GetPointData()->AddArray(data);
// there are 8 constant points (the corner points)
int corners = (1 << CORNERS) - 1;
// there are 12 variable points (the edge points)
int nCases = 1 << EDGES;
for (int i = 1; i < nCases; ++i)
{
int aCase = corners + (i << CORNERS);
g->Reset();
g->SetPoints(pts);
BuildCaseGrid(aCase, g, ptIds);
vtkNew<vtkContourFilter> cf;
cf->SetInputArrayToProcess(
0, 0, 0, vtkDataObject::FIELD_ASSOCIATION_POINTS, "AirVolumeFraction");
cf->SetValue(0, 0.5);
cf->SetInputData(g);
cf->Update();
vtkPolyData* result = cf->GetOutput();
if (!result || result->GetNumberOfCells() < 1)
{
cerr << "Case " << aCase << " has no contour" << endl;
return EXIT_FAILURE;
}
vtkNew<vtkClipDataSet> clipLess, clipMore;
clipLess->SetInsideOut(0);
clipMore->SetInsideOut(1);
clipLess->SetInputData(g);
clipMore->SetInputData(g);
clipLess->SetInputArrayToProcess(
0, 0, 0, vtkDataObject::FIELD_ASSOCIATION_POINTS, "AirVolumeFraction");
clipLess->SetValue(0.5);
clipMore->SetInputArrayToProcess(
0, 0, 0, vtkDataObject::FIELD_ASSOCIATION_POINTS, "AirVolumeFraction");
clipMore->SetValue(0.5);
clipLess->Update();
vtkUnstructuredGrid* less = clipLess->GetOutput();
if (!less || less->GetNumberOfCells() < 1)
{
cerr << "Case " << aCase << " has no 'less' clip result" << endl;
return EXIT_FAILURE;
}
clipMore->Update();
vtkUnstructuredGrid* more = clipMore->GetOutput();
if (!more || more->GetNumberOfCells() < 1)
{
cerr << "Case " << aCase << " has no 'more' clip result" << endl;
return EXIT_FAILURE;
}
}
return EXIT_SUCCESS;
}
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