WIP: Fix FFT factory names and templates_loaded flag

CMake/itkFFTImageFilterFactoryRegisterManager.h.in → CMake/itkFFTImageFilterInitFactoryRegisterManager.h.in

@@ -16,8 +16,8 @@
  *
  *=========================================================================*/
 
-#ifndef itkFFTImageFilterFactoryRegisterManager_h
-#define itkFFTImageFilterFactoryRegisterManager_h
+#ifndef itkFFTImageFilterInitFactoryRegisterManager_h
+#define itkFFTImageFilterInitFactoryRegisterManager_h
 
 namespace itk {
 
@@ -27,10 +27,10 @@ namespace itk {
 //
 @LIST_OF_FACTORIES_REGISTRATION@
 
-class FFTImageFilterFactoryRegisterManager
+class FFTImageFilterInitFactoryRegisterManager
 {
   public:
-  explicit FFTImageFilterFactoryRegisterManager(void (* const list[])(void))
+  explicit FFTImageFilterInitFactoryRegisterManager(void (* const list[])(void))
   {
     for(;*list != nullptr; ++list)
       {
@@ -44,10 +44,10 @@ class FFTImageFilterFactoryRegisterManager
 // application translation units. Note that this code will be expanded in the
 // ITK-based applications and not in ITK itself.
 //
-void (* const FFTImageFilterFactoryRegisterRegisterList[])(void) = {
+void (* const FFTImageFilterInitFactoryRegisterRegisterList[])(void) = {
   @LIST_OF_FACTORY_NAMES@
   nullptr};
-const FFTImageFilterFactoryRegisterManager FFTImageFilterFactoryRegisterManagerInstance(FFTImageFilterFactoryRegisterRegisterList);
+const FFTImageFilterInitFactoryRegisterManager FFTImageFilterInitFactoryRegisterManagerInstance(FFTImageFilterInitFactoryRegisterRegisterList);
 
 }
 

Modules/Filtering/FFT/itk-module.cmake

@@ -5,10 +5,10 @@ computations of Fast Fourier Transforms based on
 <a href=\"http://www.fftw.org\">FFTW</a>. Note that when using the FFTW
 implementation you must comply with the GPL license.")
 
-set(_fft_backends "FFTImageFilter::Vnl")
+set(_fft_backends "FFTImageFilterInit::Vnl")
 if(ITK_USE_FFTWF OR ITK_USE_FFTWD)
   # Prepend so that FFTW constructor is preferred
-  list(PREPEND _fft_backends "FFTImageFilter::FFTW")
+  list(PREPEND _fft_backends "FFTImageFilterInit::FFTW")
 endif()
 
 itk_module(ITKFFT

Wrapping/Generators/Python/itk/support/base.py

@@ -80,11 +80,6 @@ def itk_load_swig_module(name: str, namespace=None):
                     namespace[k] = v
         return
 
-    # We're definitely going to load the templates. We set templates_loaded
-    # here instead of at the end of the file to protect against cyclical
-    # dependencies that could kill the recursive lookup below.
-    this_module.__templates_loaded = True
-
     # Now, we definitely need to load the template_feature instantiations from the
     # named module, and possibly also load the underlying SWIG module. Before
     # we can load the template_feature instantiations of this module, we need to load
@@ -101,6 +96,11 @@ def itk_load_swig_module(name: str, namespace=None):
         for dep in deps:
             itk_load_swig_module(dep, namespace)
 
+    # TODO check if module was loaded as part of underlying
+    # dependency load, such as the case where this module
+    # defined a factory overload for a dependency module
+    # and was manually loaded early.
+
     if itkConfig.ImportCallback:
         itkConfig.ImportCallback(name, 0)
 
@@ -206,6 +206,11 @@ def itk_load_swig_module(name: str, namespace=None):
                     f"exception:\n {e}"
                 )
 
+    # Indicate that templates have been fully loaded from the module.
+    # Any subsequent attempts to load the module will bail out early
+    # if this flag is set.
+    this_module.__templates_loaded = True
+
     for snakeCaseFunction in l_data.get_snake_case_functions():
         namespace[snakeCaseFunction] = getattr(l_module, snakeCaseFunction)
         init_name = snakeCaseFunction + "_init_docstring"
@@ -321,12 +326,14 @@ def load_factories(factory_name: str) -> None:
     # Only load factories once
     if factory_name in _factories_loaded:
         return
-    import importlib
+
     import itk
     for module_name, data in itk_base_global_module_data.items():
         for name, factory_class_prefix in data.get_module_factories()[:2]:
             if name == factory_name:
+                # Get the factory, loading new modules with itk_load_swig_module as necessary
                 factory = getattr(itk, f"{factory_class_prefix}{name}Factory")
+                # Static method initializes factory overrides without adding to auto_pipeline
                 factory.RegisterOneFactory()
     _factories_loaded.append(factory_name)
 

Wrapping/Generators/Python/itk/support/extras.py

@@ -1040,8 +1040,6 @@ def meshwrite(
     The writer is instantiated according to the type of the input mesh.
     """
     import itk
-    from itk.support.base import load_factories
-    load_factories('MeshIO')
 
     mesh.UpdateOutputInformation()
     # don't put that writer in the automatic pipeline
@@ -1072,8 +1070,6 @@ def meshread(
     wrapped).
     """
     import itk
-    from itk.support.base import load_factories
-    load_factories('MeshIO')
 
     if fallback_only:
         if pixel_type is None:
@@ -1123,8 +1119,6 @@ def transformread(filename: fileiotype) -> List["itkt.TransformBase"]:
     A Python list containing the transforms in the file.
     """
     import itk
-    from itk.support.base import load_factories
-    load_factories('TransformIO')
 
     reader = itk.TransformFileReaderTemplate[itk.D].New()
     reader.SetFileName(f"{filename}")
@@ -1160,8 +1154,6 @@ def transformwrite(
         Use compression, if the file format supports it.
     """
     import itk
-    from itk.support.base import load_factories
-    load_factories('TransformIO')
 
     writer = itk.TransformFileWriterTemplate[itk.D].New()
     writer.SetFileName(f"{filename}")