DriveWorks SDK Reference
3.5.78 Release
For Test and Development only

Map Tracker Sample
SW Release Applicability: This sample is available in NVIDIA DRIVE Software releases.


The Map Tracker sample demonstrates how to use the map tracker from the Maps module to robustly determine the lane where the vehicle can travel.

In the following situations, selecting the current lane by merely looking for the closest point can yield erroneous results:

  • Lanes are crossing one another, such as when lanes exit or merge.
  • Localization is not completely accurate.
  • Height information is lacking when travelling on bridges. This situation can be especially problematic.

You can avoid incorrect lane assignments resulting from the above situations by pruning the lane candidates, using temporal coherence, and comparing the vehicle and lane orientations. These methods take advantage of the likelihood that the vehicle is traveling along the lane.

The sample shows the application of the map tracker by projecting a virtual vehicle in the selected current lane and and identifying candidate lanes where the vehicle could go.

Running the Sample

The command line for the map access sample, sample_maptracker, is:


While the application is running the following actions are possible:

  • 'F1' displays controls on screen.
  • 'Esc' closes the application.
  • 'Spacebar' pauses the application.
  • 'Mouse Wheel' allows to control camera zoom.
  • 'right' mouse button allow to move the camera when the sample is paused.
  • 'Up' and 'Down' arrow keys move the vehicle forward or backward.


The HD map is rendered with lines of different colors:

  • Blue lines: lane dividers that cannot be crossed.
  • Dark green lines: lane dividers that can be crossed.
  • Grey lines: invisible lane dividers.

Map Tracker output:

  • Green lines: candidate lanes used by the map tracker to select the current lane
  • Orange line: current lane returned by the map tracker

Additional info:

  • Long yellow box: current pose of the vehicle
Map Tracker Sample

Additional Information

For more details see Maps.