[vtkusers] ICP and Transforms

[Sean Richards]

My problem is not that the transformation is not being applied, the problem is that the transformation is not being created. Even though I have added the planes as the source and target, the ICPTransform says that the inputs are null (due to the fact that they have no points). Do I actually have to create points from the surface of the planes in order to use vtkICPTransform? If this is the case, how would I create a point set from vtkPolyData?

Thanks!

Sean

> vtkICPTransform only calculates the optimal 
> transform for mapping the 
> source onto the target. It doesn't actually 
> apply it to anything. 
> Once you've hooked vtkICPTransform into your 
> pipeline, you need to use 
> vtkTransformFilter to actually apply it to a 
> dataset (your source data 
> usually). Since vtkICPTransform is a subclass 
> of vtkTransform, you can 
> set it as the transform for 
> vtkTrnasformFilter. You don't need to call 
> 'MakeTransform'. 
> Attached is a demo (hit 'u' to iterate the 
> source points towards their 
> target). 
> HTH 
> Bryan 
> On Thu, 2004-08-12 at 14:49, Sean Richards 
> wrote: 
> > Hello all! :) 
> > 
> > I am trying to use 
> vtkIterativeClosestPointTransform, but seem to 
> be having a hard time getting used to it. I 
> started by trying to use regular planes to 
> test the algorithm, but can't seem to get it 
> to work. Below is the code and output I get 
> when I execute the code. Any help would be 
> very much appreciated. 
> > 
> > Thanks in advance! 
> > 
> > Sean 
> > 
> > ******************************************** 
> > **** THE CODE **** 
> > ******************************************** 
> > 
> > 	vtkPlaneSource *plane0 = 
> vtkPlaneSource::New(); 
> > 		plane0->SetResolution(25, 25); 
> > 		plane0->SetOrigin(-1,-1,0); 
> > 		plane0->SetPoint1(1,-1,0); 
> > 		plane0->SetPoint2(-1,1,0); 
> > 
> > 	vtkPlaneSource *plane1 = 
> vtkPlaneSource::New(); 
> > 		plane1->SetResolution(25, 25); 
> > 		plane1->SetOrigin(-1,-1,1); 
> > 		plane1->SetPoint1(1,-1,1); 
> > 		plane1->SetPoint2(-1,1,1); 
> > 
> > 	vtkIterativeClosestPointTransform *icp = 
> vtkIterativeClosestPointTransform::New(); 
> > 
> > 		icp->SetCheckMeanDistance(1); 
> > 		icp->SetMaximumMeanDistance(0.001); 
> > 		icp->SetMaximumNumberOfIterations(30); 
> > 		icp->SetMaximumNumberOfLandmarks(50); 
> > 
> > 		icp->SetSource((vtkDataSet 
> *)plane0->GetOutput()); 
> > 		icp->SetTarget((vtkDataSet 
> *)plane1->GetOutput()); 
> > 
> > 		// debug output 
> > 		cout << "Number of Source Points: " << 
> icp->GetSource()->GetNumberOfPoints() << "\n"; 
> > 		cout << "Number of Target Points: " << 
> icp->GetTarget()->GetNumberOfPoints() << "\n"; 
> > 
> > 		icp->Modified(); 
> > 		icp->Update(); 
> > 
> > 		cout << "\n\nOutput from 
> icp->PrintSelf(cout, 0);\n\n"; 
> > 		icp->PrintSelf(cout, 0); 
> > 
> > 		vtkAbstractTransform *transform = 
> icp->MakeTransform(); 
> > 		cout << "\n\nOutput from 
> transform->Print(cout);\n\n"; 
> > 		transform->Print(cout); 
> > 
> > ******************************************** 
> > **** THE OUTPUT **** 
> > ******************************************** 
> > 
> > ******** 
> > This output is in the vtkOutputWindow 
> > ******** 
> > 
> > ERROR: In 
> 
> 
> \thesisroot\Vtk\Hybrid\vtkIterativeClosestPointTransform.cxx, line 271 
> > vtkIterativeClosestPointTransform 
> (00336E00): Can't execute with NULL or empty 
> input 
> > 
> > ******** 
> > This output is in the console window 
> > ******** 
> > 
> > Number of Source Points: 0 
> > Number of Target Points: 0 
> > 
> > 
> > Output from icp->PrintSelf(cout, 0); 
> > 
> > Debug: Off 
> > Modified Time: 50 
> > Reference Count: 1 
> > Registered Events: (none) 
> > Inverse: (00000000) 
> > Matrix: (00336F98) 
> > Debug: Off 
> > Modified Time: 41 
> > Reference Count: 1 
> > Registered Events: (none) 
> > Elements: 
> > 1 0 0 0 
> > 0 1 0 0 
> > 0 0 1 0 
> > 0 0 0 1 
> > Source: 00336238 
> > Target: 00336998 
> > Locator: (none) 
> > MaximumNumberOfIterations: 30 
> > CheckMeanDistance: 1 
> > MeanDistanceMode: RMS 
> > MaximumMeanDistance: 0.001 
> > MaximumNumberOfLandmarks: 50 
> > StartByMatchingCentroids: 0 
> > NumberOfIterations: 0 
> > MeanDistance: 0 
> > LandmarkTransform: 
> > Debug: Off 
> > Modified Time: 42 
> > Reference Count: 1 
> > Registered Events: (none) 
> > Inverse: (00000000) 
> > Matrix: (00337208) 
> > Debug: Off 
> > Modified Time: 43 
> > Reference Count: 1 
> > Registered Events: (none) 
> > Elements: 
> > 1 0 0 0 
> > 0 1 0 0 
> > 0 0 1 0 
> > 0 0 0 1 
> > Mode: Similarity 
> > SourceLandmarks: 00000000 
> > TargetLandmarks: 00000000 
> > 
> > 
> > Output from transform->Print(cout); 
> > 
> > vtkIterativeClosestPointTransform (00337568) 
> > Debug: Off 
> > Modified Time: 55 
> > Reference Count: 1 
> > Registered Events: (none) 
> > Inverse: (00000000) 
> > Matrix: (00337770) 
> > Debug: Off 
> > Modified Time: 54 
> > Reference Count: 1 
> > Registered Events: (none) 
> > Elements: 
> > 1 0 0 0 
> > 0 1 0 0 
> > 0 0 1 0 
> > 0 0 0 1 
> > Source: (none) 
> > Target: (none) 
> > Locator: (none) 
> > MaximumNumberOfIterations: 50 
> > CheckMeanDistance: 0 
> > MeanDistanceMode: RMS 
> > MaximumMeanDistance: 0.01 
> > MaximumNumberOfLandmarks: 200 
> > StartByMatchingCentroids: 0 
> > NumberOfIterations: 0 
> > MeanDistance: 0 
> > LandmarkTransform: 
> > Debug: Off 
> > Modified Time: 55 
> > Reference Count: 1 
> > Registered Events: (none) 
> > Inverse: (00000000) 
> > Matrix: (003379E0) 
> > Debug: Off 
> > Modified Time: 56 
> > Reference Count: 1 
> > Registered Events: (none) 
> > Elements: 
> > 1 0 0 0 
> > 0 1 0 0 
> > 0 0 1 0 
> > 0 0 0 1 
> > Mode: Similarity 
> > SourceLandmarks: 00000000 
> > TargetLandmarks: 00000000