Displaced detector

include/rtkDisplacedDetectorForOffsetFieldOfViewImageFilter.hxx

@@ -65,6 +65,18 @@ DisplacedDetectorForOffsetFieldOfViewImageFilter<TInputImage, TOutputImage>::Gen
                              << "Consider disabling it by setting m_Disable=true "
                              << "or using the nodisplaced flag of the application you are running");
   }
+  else if (this->GetGeometry()->GetSourceToDetectorDistances().front() == 0.)
+  {
+    itkGenericExceptionMacro(<< "Displaced detector cannot handle parallel geometry. "
+                             << "Consider disabling it by setting m_Disable=true "
+                             << "or using the nodisplaced flag of the application you are running");
+  }
+
+  if (this->GetOffsetsSet())
+  {
+    itkGenericExceptionMacro(<< "DisplacedDetectorForOffsetFieldOfViewImageFilter cannot use manually set offsets. "
+                             << "Use DisplacedDetectorImageFilter when processing independent projections.");
+  }
 
   using FOVFilterType = typename rtk::FieldOfViewImageFilter<OutputImageType, OutputImageType>;
   auto fieldofview = FOVFilterType::New();

include/rtkDisplacedDetectorImageFilter.h

@@ -116,6 +116,9 @@ class ITK_TEMPLATE_EXPORT DisplacedDetectorImageFilter : public itk::InPlaceImag
   itkGetMacro(InferiorCorner, double);
   itkGetMacro(SuperiorCorner, double);
 
+  /** Returns true when offsets were explicitly provided */
+  itkGetMacro(OffsetsSet, bool);
+
   /** Checks that inputs are correctly set. */
   void
   VerifyPreconditions() const override;

include/rtkDisplacedDetectorImageFilter.hxx

@@ -110,6 +110,12 @@ DisplacedDetectorImageFilter<TInputImage, TOutputImage>::GenerateOutputInformati
                              << "Consider disabling it by setting m_Disable=true "
                              << "or using the nodisplaced flag of the application you are running");
   }
+  else if (this->GetGeometry()->GetSourceToDetectorDistances().front() == 0.)
+  {
+    itkGenericExceptionMacro(<< "Displaced detector cannot handle parallel geometry. "
+                             << "Consider disabling it by setting m_Disable=true "
+                             << "or using the nodisplaced flag of the application you are running");
+  }
 
   // Compute the X coordinates of the corners of the image
   typename Superclass::InputImageType::PointType corner;

test/rtkdisplaceddetectorcompoffsettest.cxx

@@ -6,6 +6,7 @@
 #include "rtkSheppLoganPhantomFilter.h"
 
 #include <itkStreamingImageFilter.h>
+#include <itkTestingMacros.h>
 
 /**
  * \file rtkdisplaceddetectorcompcudatest.cxx
@@ -96,6 +97,20 @@ rtkdisplaceddetectorcompoffsettest(int, char *[])
 
     CheckImageQuality<OutputImageType>(streamingCUDA->GetOutput(), streamingCPU->GetOutput(), 1.e-6, 100, 1.);
   }
+  {
+    constexpr double minOffset = -16.;
+    constexpr double maxOffset = 12.;
+
+    std::cout << "\n\n****** Case 4: manual offsets are not supported ******" << std::endl;
+
+    using OffsetDDFType = rtk::DisplacedDetectorForOffsetFieldOfViewImageFilter<OutputImageType>;
+    auto cudaddf = OffsetDDFType::New();
+    cudaddf->SetInput(slp->GetOutput());
+    cudaddf->SetGeometry(geometry);
+    cudaddf->SetOffsets(minOffset, maxOffset);
+    cudaddf->InPlaceOff();
+    ITK_TRY_EXPECT_EXCEPTION(cudaddf->Update());
+  }
 
   // If all succeed
   std::cout << "\n\nTest PASSED! " << std::endl;