Fix LaserScan reset not invalidating the time_tolerance_

[Hugal31]

Description

Fix the LaserScanDisplay not working after a reset (disable-enable, change topic, etc...).

In order to transform a LaserScan, the LaserScanDisplay tf_filter is configured with a time tolerance in order to call processMessage only if the transform is known for the beginning and the end of the scan.

LaserScanDisplay only wants to increase the tolerance, and because tf2_ros::MessageFilter doesn't have a getTolerance() accessor, LaserScanDisplay stores it locally to only update it when the required tolerance is greater than the configured one:

rviz/rviz_default_plugins/src/rviz_default_plugins/displays/laser_scan/laser_scan_display.cpp

Lines 91 to 95 in 5f7848c

	if (tolerance > filter_tolerance_) {
	filter_tolerance_ = tolerance;
	tf_filter_->setTolerance(filter_tolerance_);
	checkTolerance(filter_tolerance_);
	}

However, when re-subscribing, MessageFilterDisplay resets the tf filter, thus setting its time_tolerance back to 0. This is not caught in LaserScanFilter, which never updates the tolerance on the new filter again.

This fix sets the cached copy filter_tolerance_ back to 0. after subscribing.

Is this user-facing behavior change?

This doesn't introduce unwanted behavior, it is only a fix.

Did you use Generative AI?

Only 100% human brain juice was used.

Additional Information

A back-port down to jazzy would be great.

[mergify]

Tick the box to add this pull request to the merge queue (same as @mergifyio queue).

• Queue this pull request