New triangle interpolation method and fixes

- Triangle mode:
  - Add bind modal to set points
  - interpolate based on user defined
triangle bound to geometry
- changed: in geometry mode, points out of geometry should follow more consistantly (needs more testing)
- Better method names is UI
- fix : error when strokes are not fully selected

utils.py

@@ -124,7 +124,7 @@ def ray_cast_point(point, origin, depsgraph):
     
     tri, tri_indices = get_tri_from_face(hit_location, face_index, object_hit, depsgraph)
 
-    return object_hit, np.array(hit_location), tri, tri_indices
+    return object_hit, hit_location, tri, tri_indices
 
 def obj_ray_cast(obj, point, origin, depsgraph):
     """Wrapper for ray casting that moves the ray into object space"""
@@ -142,7 +142,7 @@ def obj_ray_cast(obj, point, origin, depsgraph):
     # Get hit location world_space
     hit_location = obj.matrix_world @ location
     tri, tri_indices = get_tri_from_face(hit_location, face_index, obj, depsgraph)
-    return obj, np.array(hit_location), tri, tri_indices
+    return obj, hit_location, tri, tri_indices
 
 
 def empty_at(name='Empty', pos=(0,0,0), collection=None, type='PLAIN_AXES', size=1, show_name=False):