Issue with hide/unhide on pointcloud topics

[harveybia]

Description
There might be a bug with visibility toggle for point clouds. When I hide and unhide the topic, the points no longer show up. This is different behavior than SceneUpdate where toggling visible / invisible works fine without needing to republish the topic.

What is interesting is that if you keep the topic view open for the point cloud topic, this behavior gets fixed. Possible lifecycle management issue? I attached a video of this behavior as well.

• Version: 1.87.0+4bc4588
• Platform: Windows, Chrome Version 122.0.6261.69 (Official Build) (64-bit)
• Data source (e.g. bag file, mcap file, rosbridge, ROS 1/2 native): manually published points through websocket API

Steps To Reproduce
We have our own visualization wrapper so the code is not for foxglove API directly. However, here's the point cloud I constructed:

    SegmentedCloudTypeT::Ptr seg(new SegmentedCloudTypeT);
    SegmentedPointT p1;
    p1.x = 0;
    p1.y = 0;
    p1.z = 0;
    p1.r = 255;
    p1.g = 0;
    p1.b = 0;
    seg->push_back(p1);

    SegmentedPointT p2;
    p2.x = 1;
    p2.y = 0;
    p2.z = 0;
    p2.r = 0;
    p2.g = 255;
    p2.b = 0;
    seg->push_back(p2);
    vis::show(seg, "cloud", "root");

2024-02-27.12-31-11.mp4

2024-02-27.12-31-39.mp4

This is how we send the point cloud over websocket:

    async def send_cloud(channel_name, frame_id):
        try:
            body = request.get_data()
            cloud = PointCloud()
            cloud.frame_id = frame_id
            cloud.point_stride = 16
            for idx, name in enumerate(['x', 'y', 'z']):
                f = cloud.fields.add()
                f.name = name
                f.offset = idx * 4
                f.type = 7
            for idx, name in enumerate(['red', 'green', 'blue', 'alpha']):
                f = cloud.fields.add()
                f.name = name
                f.offset = idx + 12
                f.type = 1
            
            cloud.data = body
            channel_id = await channel_manager.get_channel_id(PointCloud, channel_name)
            await server.send_message(channel_id, time.time_ns(), cloud.SerializeToString())
            return "OK"
        except Exception as e:
            print("Exception:", str(e))
            return "Error", 500

...

async def main():
    async with FoxgloveServer("0.0.0.0", 8765, "example server") as server:
        await server.wait_opened()
        print("started server")

        app = await create_app(server)
        print("created app")
        await run_flask(app)

Expected Behavior
Point cloud should show up after toggling visibility.

[linear[bot]]

FG-6819 Issue with hide/unhide on pointcloud topics

[defunctzombie]

This was fixed some time ago but we forgot to update here.