Fix camera movement

Use position instead of offset

GCC2D.gd

@@ -19,12 +19,12 @@ func _unhandled_input(e):
 
 # Given a a position on the camera returns to the corresponding global position
 func camera2global(position):
-	var camera_center = global_position + offset
+	var camera_center = global_position + position
 	var from_camera_center_pos = position - get_camera_center_offset()
 	return camera_center + (from_camera_center_pos*zoom).rotated(rotation)
 
 func _move(event):
-	offset -= (event.relative*zoom).rotated(rotation)
+	position -= (event.relative*zoom).rotated(rotation)
 
 func _zoom(event):
 	var li = event.distance
@@ -43,13 +43,13 @@ func _zoom(event):
 		zd = zf - zi
 
 	var from_camera_center_pos = event.position - get_camera_center_offset()
-	offset -= (from_camera_center_pos*zd).rotated(rotation)
+	position -= (from_camera_center_pos*zd).rotated(rotation)
 	zoom = zf*Vector2.ONE
 
 func _rotate(event):
 	var fccp = (event.position - get_camera_center_offset()) # from_camera_center_pos = fccp
 	var fccp_op_rot =  -fccp.rotated(event.relative)
-	offset -= ((fccp_op_rot + fccp)*zoom).rotated(rotation-event.relative)
+	position -= ((fccp_op_rot + fccp)*zoom).rotated(rotation-event.relative)
 	rotation -= event.relative
 
 func get_camera_center_offset():