Fix export with mirrored objects dfki-ric#377

Author: AlpenAalAlex

phobos/blender/io/blender2phobos.py

@@ -119,7 +119,7 @@ def deriveGeometry(obj, duplicate_mesh=False, fast_init=True, **kwargs):
     elif gtype == 'mesh':
         blender_mesh = obj.data.copy() if duplicate_mesh else obj.data
         return representation.Mesh(
-            scale=list(obj.matrix_world.to_scale()),
+            scale=list(obj.scale),
             mesh=blender_mesh,
             meshname=blender_mesh.name,
             fast_init=fast_init

phobos/utils/transform.py

@@ -49,10 +49,13 @@ def rpy_to_matrix(rpy):
 
 
 def matrix_to_rpy(R):
-    try:
-        angles = Rot.from_matrix(R).as_euler(EULER_CONVENTION)
-    except:
-        angles = Rot.from_dcm(R).as_euler(EULER_CONVENTION)
+    determinant = np.linalg.det(R)
+    if determinant < 0:  # This is a reflection matrix
+        scale = np.sign(np.diag(R))
+        scaling_matrix = np.diag(scale)
+        R = np.dot(R, np.linalg.inv(scaling_matrix))
+    angles = Rot.from_matrix(R).as_euler(EULER_CONVENTION)
+
     return order_angles(angles, EULER_CONVENTION, RPY_CONVENTION)