Array properties can be given single driver now

Previously, connecting a single driver to an array was an error
While trying to generate a warning, I found out it was easier to just implicitlly
use the single driver for all three channels... for some properties anyway.

utilities/drivers.py

@@ -52,102 +52,107 @@ def CreateDrivers(drivers):
     def brackets(s):
         return "[\""+s+"\"]"
     from bpy.types import Object, Key
+    fcurves = []
     for driver in drivers:
         if (isinstance(driver["owner"], Object)):
             ob = driver["owner"]
         else: # Pose Bone:
             ob = driver["owner"].id_data
         if isinstance(driver["owner"], Key):
-            fc = ob.driver_add(driver["prop"])
+            fcurves = ob.driver_add(driver["prop"])
         else:
-            fc = ob.driver_add(driver["owner"].path_from_id(driver["prop"]), driver["ind"])
-        drv = fc.driver
-        try: # annoyingly, this initializes with a modifier
-            fc.modifiers.remove(fc.modifiers[0])
-        except IndexError: #haven't seen this happen, but should handle
-            pass # perhaps this has been fixed for 3.0?
-        if version >= (5,0,0): # and now it initializes with keys. p
-            fc.keyframe_points.clear()
-        drv.type = driver["type"]
-        if (expr := driver.get("expression")) and isinstance(expr, str):
-            drv.expression = expr
-
-        fc.extrapolation = "CONSTANT"
-        if (extrapolation_mode := driver.get("extrapolation")) in ("CONSTANT", "LINEAR"):
-            fc.extrapolation = extrapolation_mode
-        else:
-            prRed(f"Extrapolation Mode in driver has incorrect data: {extrapolation_mode}")
+            fcurves = ob.driver_add(driver["owner"].path_from_id(driver["prop"]), driver["ind"])
+        if not isinstance(fcurves, list):
+            fcurves = [fcurves] # ususally it is a single fCurve, sometimes it is a list
+            # for e.g. array properties if driver_add is given -1 as index
+        for fc in fcurves:
+            drv = fc.driver
+            try: # annoyingly, this initializes with a modifier
+                fc.modifiers.remove(fc.modifiers[0])
+            except IndexError: #haven't seen this happen, but should handle
+                pass # perhaps this has been fixed for 3.0?
+            if version >= (5,0,0): # and now it initializes with keys. p
+                fc.keyframe_points.clear()
+            drv.type = driver["type"]
+            if (expr := driver.get("expression")) and isinstance(expr, str):
+                drv.expression = expr
+
+            fc.extrapolation = "CONSTANT"
+            if (extrapolation_mode := driver.get("extrapolation")) in ("CONSTANT", "LINEAR"):
+                fc.extrapolation = extrapolation_mode
+            else:
+                prRed(f"Extrapolation Mode in driver has incorrect data: {extrapolation_mode}")
 
-        # logic for handling type can go here
+            # logic for handling type can go here
 
-        # start by clearing
-        while (len(drv.variables) > 0):
-            v = drv.variables[0]
-            dVar = drv.variables.remove(v)
+            # start by clearing
+            while (len(drv.variables) > 0):
+                v = drv.variables[0]
+                dVar = drv.variables.remove(v)
 
-        for v in driver["vars"]:
-            pose_bone = False
-            bone = ''; target2bone = ''
-            vob, target2ob = None, None
-            if (isinstance(v["owner"], Object)):
-                vob = v["owner"]
-            else:
-                pose_bone = True
-                vob = v["owner"].id_data
-                bone = v["owner"].name
-            #
-
-            if "xForm 2" in v.keys() and v["xForm 2"]:
-                if (isinstance(v["xForm 2"], Object)):
-                    target2ob = v["xForm 2"]
+            for v in driver["vars"]:
+                pose_bone = False
+                bone = ''; target2bone = ''
+                vob, target2ob = None, None
+                if (isinstance(v["owner"], Object)):
+                    vob = v["owner"]
                 else:
-                    target2ob = v["xForm 2"].id_data
-                    target2bone = v["xForm 2"].name
-
-            dVar = drv.variables.new()
-
-
-            dVar.name = v["name"]
-            dVar.type = v["type"]
-            #for now, assume this is always true:
-            #dVar.targets[0].id_type = "OBJECT"
-            #it's possible to use other datablocks, but this is not commonly done
-            #actually, it looks like Blender figures this out for me.
-
-            dVar.targets[0].id = vob
-            dVar.targets[0].bone_target = bone
-            if len(dVar.targets) > 1:
-                dVar.targets[1].id = target2ob
-                dVar.targets[1].bone_target = target2bone
-
-            if (dVar.type == "TRANSFORMS"):
-                dVar.targets[0].transform_space = v["space"]
-                dVar.targets[0].transform_type = v["channel"]
-            if (dVar.type == 'SINGLE_PROP'):
-                if pose_bone:
-                    stub = "pose.bones[\""+v["owner"].name+"\"]"
-                    dVar.targets[0].data_path = stub + brackets(v["prop"])
-                    if (hasattr( v["owner"], v["prop"] )):
-                        dVar.targets[0].data_path = stub + "."+ (v["prop"])
-                    # else: # the property may be added later.
-                    # TODO BUG I want a guarantee that this property is already there.
+                    pose_bone = True
+                    vob = v["owner"].id_data
+                    bone = v["owner"].name
+                #
+
+                if "xForm 2" in v.keys() and v["xForm 2"]:
+                    if (isinstance(v["xForm 2"], Object)):
+                        target2ob = v["xForm 2"]
+                    else:
+                        target2ob = v["xForm 2"].id_data
+                        target2bone = v["xForm 2"].name
+
+                dVar = drv.variables.new()
+
+
+                dVar.name = v["name"]
+                dVar.type = v["type"]
+                #for now, assume this is always true:
+                #dVar.targets[0].id_type = "OBJECT"
+                #it's possible to use other datablocks, but this is not commonly done
+                #actually, it looks like Blender figures this out for me.
+
+                dVar.targets[0].id = vob
+                dVar.targets[0].bone_target = bone
+                if len(dVar.targets) > 1:
+                    dVar.targets[1].id = target2ob
+                    dVar.targets[1].bone_target = target2bone
+
+                if (dVar.type == "TRANSFORMS"):
+                    dVar.targets[0].transform_space = v["space"]
+                    dVar.targets[0].transform_type = v["channel"]
+                if (dVar.type == 'SINGLE_PROP'):
+                    if pose_bone:
+                        stub = "pose.bones[\""+v["owner"].name+"\"]"
+                        dVar.targets[0].data_path = stub + brackets(v["prop"])
+                        if (hasattr( v["owner"], v["prop"] )):
+                            dVar.targets[0].data_path = stub + "."+ (v["prop"])
+                        # else: # the property may be added later.
+                        # TODO BUG I want a guarantee that this property is already there.
 
-                else:
-                    if (hasattr( v["owner"], v["prop"] )):
-                        dVar.targets[0].data_path = (v["prop"])
                     else:
-                        dVar.targets[0].data_path = brackets(v["prop"])
-        # setup keyframe points
-        kp = fc.keyframe_points
-        for key in driver["keys"]:
-            k = kp.insert(frame=key["co"][0], value = key["co"][1],)
-
-            k.interpolation     = key["interpolation"]
-            if (key["interpolation"] == 'BEZIER'):
-                k.handle_left_type  = key["handle_left_type" ]
-                k.handle_right_type = key["handle_right_type"]
-                if (k.handle_left_type in ("ALIGNED", "VECTOR", "FREE")):
-                    k.handle_left       = (k.co[0] + key["handle_left"][0], k.co[1] + key["handle_left"][1])
-                if (k.handle_right_type in ("ALIGNED", "VECTOR", "FREE")):
-                    k.handle_right      = (k.co[0] + key["handle_right"][0], k.co[1] + key["handle_right"][1])
-            k.type = key["type"]
+                        if (hasattr( v["owner"], v["prop"] )):
+                            dVar.targets[0].data_path = (v["prop"])
+                        else:
+                            dVar.targets[0].data_path = brackets(v["prop"])
+            # setup keyframe points
+            kp = fc.keyframe_points
+            for key in driver["keys"]:
+                k = kp.insert(frame=key["co"][0], value = key["co"][1],)
+
+                k.interpolation     = key["interpolation"]
+                if (key["interpolation"] == 'BEZIER'):
+                    k.handle_left_type  = key["handle_left_type" ]
+                    k.handle_right_type = key["handle_right_type"]
+                    if (k.handle_left_type in ("ALIGNED", "VECTOR", "FREE")):
+                        k.handle_left       = (k.co[0] + key["handle_left"][0], k.co[1] + key["handle_left"][1])
+                    if (k.handle_right_type in ("ALIGNED", "VECTOR", "FREE")):
+                        k.handle_right      = (k.co[0] + key["handle_right"][0], k.co[1] + key["handle_right"][1])
+                k.type = key["type"]