materialx_serializer.ProtobufToMaterialX Class Reference

Converter class to transform Protobuf MaterialXDocument messages back into MaterialX document objects. More...

Public Member Functions
	convert (self, pb_doc, mx)
	Convert a Protobuf MaterialXDocument message to a MaterialX document object.

Protected Member Functions
	_check_version_and_upgrade (self, pb_doc, mx)
	Check schema version and perform upgrades if necessary.
	_convert_element (self, pb_elem, parent, mx)
	Recursively convert a Protobuf MaterialXElement to a MaterialX element.

Detailed Description

Converter class to transform Protobuf MaterialXDocument messages back into MaterialX document objects.

• Traverses the Protobuf message structure and reconstructs the corresponding MaterialX document hierarchy.
• Handles attributes and child elements recursively.
• Requires the MaterialX Python API to create and manipulate document elements.
• Usage: converter = ProtobufToMaterialX() mx_doc = converter.convert(pb_doc, mx)
• Where pb_doc is a MaterialXDocument Protobuf message and mx is the MaterialX Python module.

Member Function Documentation

_check_version_and_upgrade()

materialx_serializer.ProtobufToMaterialX._check_version_and_upgrade ( self, pb_doc, mx )

protected

Check schema version and perform upgrades if necessary.

Parameters

pb_doc	The Protobuf MaterialXDocument message.
mx	The MaterialX Python module.

Returns

A new MaterialX document object.

    def _check_version_and_upgrade(self, pb_doc, mx):
        """
        @brief Check schema version and perform upgrades if necessary.
        @param pb_doc The Protobuf MaterialXDocument message.
        @param mx The MaterialX Python module.
        @return A new MaterialX document object.
        """
        doc = mx.createDocument()
        
        # Check if version is set
        if pb_doc.HasField('schema_version'):
            major = pb_doc.schema_version.major
            minor = pb_doc.schema_version.minor
            patch = pb_doc.schema_version.patch
            
            # Version compatibility check
            if major > SCHEMA_VERSION_MAJOR:
                raise ValueError(
                    f"Document schema version {major}.{minor}.{patch} is newer than "
                    f"supported version {SCHEMA_VERSION_MAJOR}.{SCHEMA_VERSION_MINOR}.{SCHEMA_VERSION_PATCH}. "
                    f"Please upgrade your software."
                )
            
            # Perform upgrades for older versions
            if major < SCHEMA_VERSION_MAJOR:
                print(f"Warning: Upgrading document from version {major}.{minor}.{patch} "
                      f"to {SCHEMA_VERSION_MAJOR}.{SCHEMA_VERSION_MINOR}.{SCHEMA_VERSION_PATCH}")
                # Add upgrade logic here when needed
                # self._upgrade_v0_to_v1(pb_doc)            
        else:
            # No version info - assume oldest supported version
            print("Warning: Document has no schema version information. Assuming legacy format.")
        
        return doc
    

_convert_element()

materialx_serializer.ProtobufToMaterialX._convert_element ( self, pb_elem, parent, mx )

protected

Recursively convert a Protobuf MaterialXElement to a MaterialX element.

Parameters

pb_elem	The Protobuf MaterialXElement message to convert.
parent	The parent MaterialX element to which the new element will be added.
mx	The MaterialX Python module for element creation.

Returns

The newly created MaterialX element.

    def _convert_element(self, pb_elem, parent, mx):
        """
        @brief Recursively convert a Protobuf MaterialXElement to a MaterialX element.
        @param pb_elem The Protobuf MaterialXElement message to convert.
        @param parent The parent MaterialX element to which the new element will be added.
        @param mx The MaterialX Python module for element creation.
        @return The newly created MaterialX element.
        """
        # Create element
        #print('Creating element:', pb_elem.type, pb_elem.name)
        mx_elem = parent.addChildOfCategory(pb_elem.type, pb_elem.name)
        
        # Set all attributes preserving order
        for attr in pb_elem.attributes:
            #print(' Setting attribute:', attr.key, '=', attr.value)
            mx_elem.setAttribute(attr.key, attr.value)
        
        # Recursively convert children
        for pb_child in pb_elem.children:
            child_elem = self._convert_element(pb_child, mx_elem, mx)
            #print(' Adding child element:', child_elem.getCategory(), child_elem.getName())
            
        return mx_elem

convert()

materialx_serializer.ProtobufToMaterialX.convert	(		self,
			pb_doc,
			mx )

Convert a Protobuf MaterialXDocument message to a MaterialX document object.

Parameters

pb_doc	The Protobuf MaterialXDocument message to convert.
mx	The MaterialX Python module for document creation.

Returns

The reconstructed MaterialX document object.

    def convert(self, pb_doc, mx):
        """
        Convert a Protobuf MaterialXDocument message to a MaterialX document object.
        @param pb_doc The Protobuf MaterialXDocument message to convert.
        @param mx The MaterialX Python module for document creation.
        @return The reconstructed MaterialX document object.
        """
        # Check version compatibility and upgrade if needed
        doc = self._check_version_and_upgrade(pb_doc, mx)
        
        for pb_attribute in pb_doc.attributes:
            doc.setAttribute(pb_attribute.key, pb_attribute.value)
 
        for pb_element in pb_doc.elements:
            mx_element = self._convert_element(pb_element, doc, mx)
            
        return doc
    

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The documentation for this class was generated from the following file:

• materialx_serializer.py