Add ViewFaceMods.

The ViewFaceMod is presented as a Swivel component, with artist-ready
presets for the typical Sprite and Billboard, as well as an advanced
'Custom' option which exposes additional features.

korman/properties/modifiers/render.py

@@ -19,6 +19,8 @@ from bpy.props import *
 from PyHSPlasma import *
 
 from .base import PlasmaModifierProperties
+from ...exporter import utils
+from ...exporter.explosions import ExportError
 
 class PlasmaLightMapGen(PlasmaModifierProperties):
     pl_id = "lightmap"
@@ -86,3 +88,88 @@ class PlasmaLightMapGen(PlasmaModifierProperties):
     @property
     def resolution(self):
         return int(self.quality)
+
+class PlasmaViewFaceMod(PlasmaModifierProperties):
+    pl_id = "viewfacemod"
+
+    bl_category = "Render"
+    bl_label = "Swivel"
+    bl_description = "Swivel object to face the camera, player, or another object"
+
+    preset_options = EnumProperty(name="Type",
+                                  description="Type of Facing",
+                                  items=[
+                                         ("Billboard", "Billboard", "Face the camera (Y Axis only)"),
+                                         ("Sprite", "Sprite", "Face the camera (All Axis)"),
+                                         ("Custom", "Custom", "Custom Swivel"),
+                                   ])
+
+    follow_mode = EnumProperty(name="Target Type",
+                               description="Target of the swivel",
+                               items=[
+                                      ("kFaceCam", "Camera", "Face the camera"),
+                                      ("kFaceList", "Listener", "Face listeners"),
+                                      ("kFacePlay", "Player", "Face the local player"),
+                                      ("kFaceObj", "Object", "Face an object"),
+                                ])
+    target_object = StringProperty(name="Target Object",
+                                   description="Object to face")
+
+    pivot_on_y = BoolProperty(name="Pivot on local Y",
+                              description="Swivel only around the local Y axis",
+                              default=False)
+
+    offset = BoolProperty(name="Offset", description="Use offset vector", default=False)
+    offset_local = BoolProperty(name="Local", description="Use local coordinates", default=False)
+    offset_coord = FloatVectorProperty(name="", subtype="XYZ")
+
+    def created(self, obj):
+        self.display_name = obj.name
+
+    def export(self, exporter, bo, so):
+        vfm = exporter.mgr.find_create_object(plViewFaceModifier, so=so, name=self.display_name)
+
+        # Set a default scaling (libHSPlasma will set this to 0 otherwise).
+        vfm.scale = hsVector3(1,1,1)
+        l2p = utils.matrix44(bo.matrix_local)
+        vfm.localToParent = l2p
+        vfm.parentToLocal = l2p.inverse()
+
+        # Cyan has these as separate components, but they're really just preset
+        # options for common swivels.  We've consolidated them both here, along
+        # with the fully-customizable swivel as a third option.
+        if self.preset_options == "Billboard":
+            vfm.setFlag(plViewFaceModifier.kFaceCam, True)
+            vfm.setFlag(plViewFaceModifier.kPivotY, True)
+        elif self.preset_options == "Sprite":
+            vfm.setFlag(plViewFaceModifier.kFaceCam, True)
+            vfm.setFlag(plViewFaceModifier.kPivotFace, True)
+        elif self.preset_options == "Custom":
+            # For the discerning artist, full control over their swivel options!
+            vfm.setFlag(getattr(plViewFaceModifier, self.follow_mode), True)
+
+            if self.follow_mode == "kFaceObj":
+                # If this swivel is following an object, make sure that the
+                # target has been selected and is a valid SO.
+                if self.target_object:
+                    target_obj = bpy.data.objects.get(self.target_object, None)
+                    if target_obj is None:
+                        raise ExportError("'{}': Swivel's target object is invalid".format(self.display_name))
+                    else:
+                        vfm.faceObj = exporter.mgr.find_create_key(plSceneObject, bl=target_obj)
+                else:
+                    raise ExportError("'{}': Swivel's target object must be selected".format(self.display_name))
+
+            if self.pivot_on_y:
+                vfm.setFlag(plViewFaceModifier.kPivotY, True)
+            else:
+                vfm.setFlag(plViewFaceModifier.kPivotFace, True)
+
+            if self.offset:
+                vfm.offset = hsVector3(*self.offset_coord)
+                if self.offset_local:
+                    vfm.setFlag(plViewFaceModifier.kOffsetLocal, True)
+
+    @property
+    def requires_actor(self):
+        return True

korman/ui/modifiers/render.py

@@ -32,3 +32,26 @@ def lightmap(modifier, layout, context):
         im_name = "{}_LIGHTMAPGEN.png".format(context.active_object.name)
         if tex.image.name == im_name:
             layout.template_preview(tex, show_buttons=False)
+
+def viewfacemod(modifier, layout, context):
+    layout.prop(modifier, "preset_options")
+
+    if modifier.preset_options == "Custom":
+        layout.row().prop(modifier, "follow_mode")
+        if modifier.follow_mode == "kFaceObj":
+            layout.prop_search(modifier, "target_object", bpy.data, "objects", icon="OUTLINER_OB_MESH")
+            layout.separator()
+
+        layout.prop(modifier, "pivot_on_y")
+        layout.separator()
+
+        split = layout.split()
+        col = split.column()
+        col.prop(modifier, "offset")
+        row = col.row()
+        row.enabled = modifier.offset
+        row.prop(modifier, "offset_local")
+
+        col = split.column()
+        col.enabled = modifier.offset
+        col.prop(modifier, "offset_coord")