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--- graphic:python:houdini [2023/01/18 11:11] – [Houdini Pipeline Development] ying
+++ graphic:python:houdini [2024/03/22 06:37] (current) – [HDA Operation (Houdini Digital Asset)] ying
@@ Line 69: / Line 69: @@
             print(str(node) + " description: " + d.description())
             print(str(node) + " comment: " + d.comment())
-            print(str(node) + "path: " + node.type().definition().libraryFilePath())
+            print(str(node) + " path: " + node.type().definition().libraryFilePath())
     else:
         print("Selected node is not a HDA")
@@ Line 78: / Line 78: @@
   * HDA = houdini digital asset
+    * a set of node network functions as a core process
+    * like model asset but instead of geo, it can be anything, like shading network, rig network or anything process.
+    * once you add hda path into your houdini env, you can load it from tab menu like rest built-in hda asset (like nuke gizmo)
+    * each hda is like a programming class, it has its unique type name like class name, all node of its class are instance of the node definition (its original content network)
+    * once a instance of hda in the scene, it is like maya model reference, you can unlock and make additional changes (**Allow editing of contents**),
+    * you can save the changes back into hda files (**Save node type**), or just keep changes in the scene
+    * to revert back to original state, just select node, use (**Match current definition** cmd)
+    * hda file can contain many hda assets, but recommed one asset for one hda file
+    * hda asset can be inside houdini scene file, as Embedded instead of on a path file
+    * nested hda need to be manually updated inside
+    * ref:
+      * https://www.tokeru.com/cgwiki/index.php?title=HoudiniHDA
   * VHDA = versioned houdini digital asset
     * ref: create your own videos https://vimeo.com/458751335
@@ Line 104: / Line 116: @@
 #hda related files
 assettools.py
+C:\Program Files\Side Effects Software\Houdini X\houdini\python3.7libs\assettools.py
 </code>
+  * node > definition > all info related
+===== Simple hda operation =====
+  * lock hda node <code python>result_node.matchCurrentDefinition()</code>
+  * unlock hda node (same like allow edit of content)<code python>
+if result_node.isLockedHDA():
+    result_node.allowEditingOfContents()
+</code>
+  * open type property dialog of a hda node <code python>hou.ui.openTypePropertiesDialog(result_node)</code>
+===== Complex hda operation =====
+  * node info <code python>
+# node
+if len(hou.selectedNodes()) == 1:
+    node = hou.selectedNodes()[0]
+# node info
+print(str(node) + " name: " + node.type().name() )
+print(str(node) + " locked: " + node.isLockedHDA() )
+</code>
+  * definition <code python>
+# definition
+if node.type().definition() is not None:
+    hda_def = node.type().definition()
+# definition info
+print(str(node) + " path: " + hda_def.libraryFilePath() )
+print(str(node) + " version: " + hda_def.version())
+print(str(node) + " description: " + hda_def.description())
+print(str(node) + " comment: " + hda_def.comment())
+# definition operation
+cur_def.isInstalled()
+cur_def.save(tmp_filepath, template_node=node)
+</code>
+  * hda file <code python>
+# hda file
+hda_file_path = hda_def.libraryFilePath()
+definition_list = hou.hda.definitionsInFile(hda_file_path)
+# check hda file list loaded in memory
+loaded_hda_file_list= hou.hda.loadedFiles()
+print('\n'.join(loaded_hda_file_list))
+# hda file load/unload
+hou.hda.installFile(hda_file_path)
+hou.hda.uninstallFile(hda_file_path)
+# hda file reload
+hou.hda.reloadAllFiles(True)
+</code>
  * check and remove HDA <code python>
@@ Line 122: / Line 185: @@
     # remove action
     # os.remove(cur_path)
+</code>
+How create new ... HDA works?
+  - menu calls <code python>
+import hou
+import assettools
+node = kwargs["node"] # it get node from menu click action
+assettools.createNewVHDAFromSubnet(node)
+</code>
+  - assettools.py has function createNewVHDAFromSubnet(), it basically create the dialog
+  - dialog VHDASaveAsDialog() class show up, the Create button do the node publish
+    - setMembersFromUI
+    - namespace_author, namespace_branch, major_version, minor_version = self.getCorrectNamespacesAndVersion()
+    - library_file = self.getCorrectLibraryFile()
+    - tablabel = constructVHDALabel(self.tablabel, self.namespace_branch if self.display_branch_in_label_enable else None)
+    - library_file_path = os.path.join(hou.text.expandString(self.library_dir), library_file)
+    - vhda_typename = constructVHDATypeName(namespace_author, namespace_branch, self.type_name, major_version, minor_version)
+    - continue: alert deals with lib path file contains multi- definition
+    - new asset <code python>
+createVHDA(node,
+   namespace_author,
+   namespace_branch,
+   self.type_name,
+   major_version,
+   minor_version,
+   tablabel,
+   self.tabmenu_entry,
+   self.library_dir,
+   library_file)
+</code>
+    - version up case (a versioned copy of an existing): <code python>
+copyToVHDAFile(node,
+   namespace_author,
+   namespace_branch,
+   self.type_name,
+   major_version,
+   minor_version,
+   tablabel,
+   self.tabmenu_entry,
+   self.library_dir,
+   library_file)
+</code>
+  - details of VHDA function (from assettolls.py) <code python>
+  def createVHDA(node, namespace_author, namespace_branch, name, major, minor, label, tabmenu, savedir, savefile=None):
+    hda_name  = constructVHDATypeName(namespace_author, namespace_branch,name,major,minor)
+    hda_label = label
+    hda_filename = savefile if savefile else constructVHDAFileName(namespace_author, namespace_branch,name,major,minor)
+    hda_savedir = savedir
+    hda_filepath = os.path.join(hda_savedir, hda_filename) if hda_savedir != "Embedded" else "Embedded"
+    max_num_inputs = 0
+    # If there are inputs to the node, find the largest index of the input connections and use it as the max_num_inputs
+    # This will preserve the inputs at the right indexes
+    if len(node.inputs()) > 0:
+        for connection in node.inputConnections():
+            max_num_inputs = max(max_num_inputs,connection.inputIndex())
+        max_num_inputs = max_num_inputs + 1
+    vhda_node = node.createDigitalAsset(
+        name = hda_name,
+        hda_file_name = hda_filepath,
+        description = hda_label,
+        min_num_inputs = 0,
+        max_num_inputs = max_num_inputs,
+        save_as_embedded = hda_savedir == "Embedded",
+        ignore_external_references=True,
+    )
+    vhda_node.setName(name, unique_name=True)
+    vhda_def = vhda_node.type().definition()
+    # Update and save new HDA
+    vhda_options = vhda_def.options()
+    vhda_options.setSaveInitialParmsAndContents(True)
+    #vhda_options.setSaveSpareParms(True) ####### TO-DO
+    vhda_def.setOptions(vhda_options)
+    '''
+    setVHDASection(vhda_def, False if namespace_author == "" else True,
+                             False if namespace_branch == "" else True)
+    '''
+    setToolSubmenu(vhda_def, tabmenu)
+    vhda_def.save(hda_filepath, vhda_node, vhda_options)
+    hou.hda.installFile(hda_filepath)
+    hou.hda.reloadAllFiles(True)
+</code>
+  - copyToVHDAFile <code python>
+def copyToVHDAFile(node, namespace_author, namespace_branch, name, major, minor, label, tabmenu, savedir, savefile=None):
+    hda_name  = constructVHDATypeName(namespace_author, namespace_branch,name,major,minor)
+    hda_label = label
+    hda_filename = savefile if savefile else constructVHDAFileName(namespace_author, namespace_branch,name,major,minor)
+    hda_savedir = savedir
+    hda_filepath = os.path.join(hda_savedir, hda_filename) if hda_savedir != "Embedded" else "Embedded"
+    tmp_filepath = os.path.join(hou.text.expandString("$HOUDINI_TEMP_DIR"),"tmphda.hda")
+    # Update and save new HDA
+    vhda_def = node.type().definition()
+    # vhda_options = vhda_def.options()
+    # vhda_options.setSaveInitialParmsAndContents(True)
+    # vhda_options.setSaveSpareParms(True) ####### TO-DO
+    vhda_def.save(tmp_filepath, template_node=node)
+    created_definition = hou.hda.definitionsInFile(tmp_filepath)[0]
+    # Sets the tabmenu location only if it differs from the original
+    if tabmenu:
+        setToolSubmenu(created_definition, tabmenu)
+    created_definition.copyToHDAFile(hda_filepath,hda_name,hda_label)
+    os.remove(tmp_filepath)
+    hou.hda.installFile(hda_filepath)
+    hou.hda.reloadAllFiles(True)
+    node.changeNodeType(hda_name)
 </code>
 ====== Tutorial ======