MantisBT - VTK
#include <vtkSmartPointer.h>
#include <vtkPoints.h>
#include <vtkPolyData.h>
#include <vtkPointData.h>
#include <vtkCellArray.h>
#include <vtkMath.h>
#include <vtkXMLPolyDataReader.h>
#include <vtkModifiedBSPTree.h>
#include <fstream>
#include <limits>
#include <sstream>
int main(int, char *[])
{
// Read the scene geometry
vtkSmartPointer<vtkXMLPolyDataReader> reader =
vtkSmartPointer<vtkXMLPolyDataReader>::New();
reader->SetFileName("corner.vtp");
reader->Update();
double p0[3] = {0, 0, 0};
double p1[3] = {22.2073, -15.8678, -96.2032};
vtkSmartPointer<vtkModifiedBSPTree> tree =
vtkSmartPointer<vtkModifiedBSPTree>::New();
tree->SetDataSet(reader->GetOutput());
tree->BuildLocator();
float tolerance = .001;
double t;
double x[3];
double pcoords[3];
int subId = 0;
vtkIdType cellId = 0;
std::cout << "Casting ray between " << p0[0] << " " << p0[1] << " " << p0[2]
<< " and " << p1[0] << " " << p1[1] << " " << p1[2] << std::endl;
// Perform the intersection using the tree
int treeHit = tree->IntersectWithLine(p0, p1, tolerance, t, x, pcoords, subId, cellId);
std::cout << "tree hit? " << treeHit << std::endl;
if(treeHit)
{
std::cout << "tree intersection " << x[0] << " " << x[1] << " " << x[2] << std::endl;
}
// Do the intersection manually (not using the tree)
unsigned int numberOfManualHits = 0;
bool manualHit = false;
for(vtkIdType cellIndex = 0; cellIndex < reader->GetOutput()->GetNumberOfCells(); ++cellIndex)
{
vtkIdType intersect = reader->GetOutput()->GetCell(cellIndex)->IntersectWithLine(p0, p1, tolerance, t, x, pcoords, cellId);
if(intersect)
{
manualHit = true;
break;
}
}
if(manualHit)
{
std::cout << "manual intersection " << x[0] << " " << x[1] << " " << x[2] << std::endl;
numberOfManualHits++;
}
std::cout << "manual hit? " << manualHit << std::endl;
return EXIT_SUCCESS;
}
The output when VTK was built in DEBUG mode is (correctly):
Casting ray between 0 0 0 and 22.2073 -15.8678 -96.2032
tree hit? 1
tree intersection 0.279686 -0.199844 -1.21162
manual intersection 0.279686 -0.199844 -1.21162
manual hit? 1
However, the output when VTK was built in RELEASE mode is (incorrectly):
Casting ray between 0 0 0 and 22.2073 -15.8678 -96.2032
tree hit? 0
manual intersection 0.279686 -0.199844 -1.21162
manual hit? 1
We see here that the tree indicates that there was no intersection, when there should have been one.
demo.tar.gz (7,260) 2012-12-07 16:29https://www.vtk.org/Bug/file/9364/demo.tar.gz