Road lidar and road line/polygon xyz data are produced from the ~50TB TxGIO (formerly TNRIS) state lidar collections. Road lidar is currently organized by maintenance section in each TxDOT district. Computation is done on GPU computing resources at Oak Ridge National Laboratory (ORNL), through a Strategic Partnership Project with UT Austin and an NSF ACCESS computing allocation award that interconnects TACC Corral and ORNL CADES/OLCF for fast data movement using Globus.
How are OpenStreetMap roads used in the processing?
We only consider roads with fclass of certain types. An ogr2ogr command with an SQL selection query is applied as below:
ogr2ogr -dialect sqlite -sql "select * from gis_osm_roads_free_1 where fclass in ('motorway', 'motorway_li
nk', 'tertiary', 'primary_link', 'secondary', 'residential', 'unclassified', 'primary', 'trunk', 'tertiary_link', 'trunk_link', 'secondary_link')"
-t_srs epsg:3081 osm_texas_roadlines_20250317_epsg3081.gpkg gis_osm_roads_free_1.shp -nln roadlines
How are road polygons generated?
Road polygons are generated by buffering the OSM road lines. The buffering rules are:
8-meter buffer if fclass is in ['motorway', 'secondary', 'primary', 'trunk']
5-meter buffer if fclass is in ['motorway_link', 'tertiary', 'primary_link', 'residential', 'unclassified', 'tertiary_link', 'trunk_link', 'secondary_link']
The University of Texas at Austin or Oak Ridge National Laboratory (ORNL) shall not be held liable for improper or incorrect use of the data described or information contained on this map or associated series of maps. The data and related map graphics are not legal, land survey or engineering documents and are not intended to be used as such.
The University of Texas at Austin or ORNL gives no warranty, express or implied, as to the accuracy, reliability, utility or completeness of this information. The user of these maps and data assumes all responsibility and risk for the use of the maps and data. The University of Texas at Austin and ORNL disclaim all warranties, representations or endorsements either express or implied, with regard to the information contained in this map product, including, but not limited to, all implied warranties of merchantability, fitness for a particular purpose or non-infringement.
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Community feedback is important for us to continuously improve the quality of the Road Elevation Model datasets and the underlying methodologies. Please let us know if you have any suggestions/comments or need to report an issue.
