/clock from outside sources breaks rendering

Description I am publishing a custom time on the /clock topic, and setting my nodes to use_sim_time:=true. When I use this clock topic, the point cloud in the 3D panel “flickers” it displays the latest message, the stops displaying it (almost immediately) then displays the next message when it arrives.

I am generating the topic data in ROS2, then bridging it across, however I am able to reproduce the bug via ros1 bag file.

When I run my nodes in real-time, or run the bag file with the /clock topic muted, the issue vanishes.

When I drag and drop either bag file (one with /clock and one without), Foxglove plays both back perfectly.

• Version: 0.12.0
• OS: Ubuntu 20.04

Steps To Reproduce

example.zip

1. Play bag file simclock_2021-06-23-11-15-43.bag via rosbag
2. open a 3d panel in Foxglove, showing the topic /points
3. you will see the points “flickering”
4. play either realtime_2021-06-23-11-11-39.bag or the simclock bag file excluding /clock
5. the issue no longer exists

Expected Behavior Pointcloud should render correctly regardless of /clock source

Actual Behavior Pointcloud rendering breaks

[defunctzombie]

Can confirm I am able to rosbag play the simclock bag (with and without the --clock flag to rosbag) and see flickering in the 3d panel when connected using the ROS connection in Studio.

[jhurliman]

Fixed in https://github.com/foxglove/studio/pull/2322