Convert xSitCam.py to regular engine features.

Using standard engine features should make the Ages generated by Korman
more robust. Also, any time we can avoid calling into Python, that's a
performance win.

korman/properties/modifiers/avatar.py

@@ -128,15 +128,24 @@ class PlasmaSittingBehavior(idprops.IDPropObjectMixin, PlasmaModifierProperties,
         sittingmod = nodes.new("PlasmaSittingBehaviorNode")
         sittingmod.approach = self.approach
         sittingmod.name = "SittingBeh"
-        # xSitCam.py PythonFileMod
-        if self.sitting_camera is not None:
-            sittingpynode = self._create_python_standard_file_node(tree, "xSitCam.py")
-            sittingmod.link_output(sittingpynode, "satisfies", "sitAct")
 
-            # Camera Object
-            cameraobj = nodes.new("PlasmaAttribObjectNode")
-            cameraobj.link_output(sittingpynode, "pfm", "sitCam")
-            cameraobj.target_object = self.sitting_camera
+        # Sitting Camera handling
+        if self.sitting_camera is not None:
+            sitDownRespNode = self._create_responder_nodes(
+                tree,
+                ("PlasmaCameraMsgNode", { "camera": self.sitting_camera, "cmd": "push" }),
+                detect_trigger=True, detect_untrigger=False,
+                name="SitDown"
+            )
+            standUpRespNode = self._create_responder_nodes(
+                tree,
+                ("PlasmaCameraMsgNode", { "camera": self.sitting_camera, "cmd": "pop" }),
+                detect_trigger=False, detect_untrigger=True,
+                name="StandUp"
+            )
+
+            sittingmod.link_output(sitDownRespNode, "satisfies", "condition")
+            sittingmod.link_output(standUpRespNode, "satisfies", "condition")
 
         # Clickable
         clickable = nodes.new("PlasmaClickableNode")

korman/properties/modifiers/base.py

@@ -24,6 +24,7 @@ from typing import *
 
 if TYPE_CHECKING:
     from ...nodes.node_python import *
+    from ...nodes.node_responder import *
 
 from ... import helpers
 from ... import plasma_api
@@ -237,6 +238,36 @@ class PlasmaModifierLogicWiz:
             setattr(node, i, j)
         return node
 
+    def _create_responder_nodes(
+            self, tree: bpy.types.NodeGroup,
+            *messages: Tuple[str, Dict[str, Any]],
+            **responder_settings
+        ) -> PlasmaResponderNode:
+        """Creates and links together a Responder node tree. Each message sould be specified by a tuple
+           of string message type and a dict of attributes to set on the message node. Messages will be
+           created and linked in the order they are specified, including any callback waits if needed.
+           Attributes on the responder node can be set by passing them in as keyword arguments.
+        """
+
+        nodes = tree.nodes
+        respNode = nodes.new("PlasmaResponderNode")
+        for attr, value in responder_settings.items():
+            setattr(respNode, attr, value)
+        respStateNode = nodes.new("PlasmaResponderStateNode")
+        respNode.link_output(respStateNode, "state_refs", "resp")
+
+        linkMsgTo = respStateNode
+        for msgNodeType, msgNodeAttrs in messages:
+            msgNode = nodes.new(msgNodeType)
+            for attr, value in msgNodeAttrs.items():
+                setattr(msgNode, attr, value)
+
+            linkMsgTo.link_output(msgNode, "msgs", "sender")
+            if msgNode.has_callbacks and msgNode.can_link_callbacks:
+                linkMsgTo = msgNode
+
+        return respNode
+
     @abc.abstractmethod
     def logicwiz(self, bo, tree):
         pass