Open Geospatial Consortium (OGC) Map Tile Loader Extension

Overview

The NVIDIA Omniverse™ Open Geospatial Consortium (OGC) Map Tile Loader Extension queries geospatial data following open geospatial consortium (OGC) standards and generates map tiles given user input for coordinates (latitude, longitude) and tile size.

Features

  • Tile Information Setup - Use user-defined inputs to determine bounding box of map tiles

  • Image Query - Make requests to download images for tile’s area

  • Geospatial Information - Read .tiff file for GeoTiff tags, image size, elevation per pixel

  • Terrain Mesh Generation - Given latitude and longitude from .tiff file, create and place USD meshes in georeferenced locations and manipulate mesh’s vertices to match elevation data

  • Create materials with textures using map imagery for map tile’s bounding box

Note

The tool is currently able to convert data following the WGS84 coordinate system

Note

Meshes do not curve and do not create a ellipsoidal Earth.

Generating Map Tiles

This tutorial provides the steps to generate map tiles as meshes in Omniverse Create. The OGC Map Tile Loader extension is not enabled by default in Create and will need to be enabled for use.

  1. Open NVIDIA Omniverse™ Create.

../_images/open-geospatial-consortium-extension_image_extension-window.png
  1. Navigate to Window > Extensions.

../_images/OGC-Ext_0_Open_Window_For_Ext.png
  1. Search for and enable the OGC Map Tile Loader Extension.

../_images/OGC-Ext_1_Search_for_ogc.png
  1. Navigate to Window > OGC Map Tile Loader to open the extension window.

../_images/OGC-Ext_2_Select_extension.png
  1. Click on the OGC Map Tile Loader (Beta) tab.

../_images/OGC-Ext_3_Ogc_ext_startup.png

The window is split into two settings menus: “Global Map Settings” and “Map Tile Settings.” These menus provide settings for all generated map tiles and parameters for the next tile to be generated, respectively. Below is a description of each field.

Fields

Description

Global Map Settings


Image Download URL

(string) directory path for downloaded images

Map Tile Settings


Tile Latitude (deg)

(string) Latitude coordinate of map
tile center in degrees.

Tile Longitude (deg)

(string) Longitude coordinate of map
tile center in degrees.

Latitude Distance (km)

(string) Latitude distance of map
tile center in kilometers.

Longitude Distance (km)

(string) Longitude distance of map
tile center in kilometers.

Map Imagery Selection


Map Imagery Preset

(menu) Available Web Map Server providers.
- terrestris - provides topology and OpenStreetMap
overlays for road and building features
- mundialis - provides topology and OpenStreetMap
overlays for road and building features
- Gebco - provides topology
- USGS-NationalMap - provides Satelliate imagery

OGC API

User option to query a server following OGC API queries
for map imagery and elevation data

Base URL

(string) Base URL of the server to query from

collectionID

(string) ID of the collection to query from

Advanced Settings

Parameters that are included but have default values
available for the user

transparent

(bool) transparent background for image

bgColor

(string) background color in hex format

credentials

optional - (string) credentials provided for access of server
this is dependent on how the server conducts
authentication (API key, username and password, etc.)

Custom Server

User option to query a server of choice
for map imagery and elevation data

Base URL

(string) Base URL of the server to query from

credentials

optional - (string) credentials provided for access of server
this is dependent on how the server conducts
authentication (API key, username and password, etc.)

Elevation Data Selection


Elevation Data Preset

(menu) Available Web Map Server providers.
- National Oceanic and Atmospheric Administration -
elevation data source

Base URL

(string) Base URL of the server to query from

credentials

optional - (string) credentials provided for access of server
this is dependent on how the server conducts
authentication (API key, username and password, etc.)
  1. In the “Global Map Settings” menu, for the “Image Download URL” field add the absolute path for the folder you wish to save map imagery and elevation data images to. An example URL is “C:users/jdoe/appdata/local/ov/pkg/create-2022.3.0” which is the installation folder of Create.

../_images/OGC-Ext_4_Filled_url.png

Note

Providing a relative path will causes errors. Some paths may be invalid due to user read-write permissions and whether the folder exists.

  1. In the “Map Tile Settings” menu, provide latitude (Lat) and longitude (Long) coordinates’ values.

Note

The extension supports the ESPG:4326 / WGS84 coordinate reference system (CRS). They are used to determine the bounding box with the northing and easting distances. Accepted values for latitude are [-90.0, 90.0] and for latitude are [-180.0, 180.0]. Both are in units of degrees.

  1. In the “Map Tile Settings” menu, provide northing and easting distances.

Note

These distances are the north-to-south and east-to-west distances, respectively. They are used to determine the bounding box with the latitude and longitude coordinates. Accepted values for variables are [0.0, 12741.9811]. The units are in kilometers.

  1. In the “Map Tile Settings” menu, for the “Map Imagery Selection” group you can select from either the presets, an OGC API-compliant server, or a custom server to query from.

../_images/OGC-Ext_5_Imagery_presets.png ../_images/OGC-Ext_7_Imagery_api_empty.png ../_images/OGC-Ext_8_Imagery_custom_empty.png

Note

The extension currently supports Portable Network Graphics (.png) raster file format for map imagery.

Example outputs of presets (top row, from left to right: terrestris, mundialis; bottom row, from left to right: Gebco, USGS-NationalMap):

../_images/OGC-Ext_6_Imagery_preset_outputs.png
  1. In the “Map Tile Settings” menu, for the “Elevation Data Selection” group you can select from either the presets, an OGC API-compliant server, or a custom server to query from.

../_images/OGC-Ext_9_elevation_preset.png ../_images/OGC-Ext_10_elevation_api_empty.png

Example values for API:

Fields

Example Values

Map Imagery


Base URL

collectionID

blueMarble

transparent

true

bgColor

0xFFFFFF

credentials



Elevation Data


Base URL

collectionID

SRTM_ViewFinderPanorama

credentials


../_images/OGC-Ext_11_elevation_custom_empty.png

Note

The extension currently supports digital elevation model (DEM) files of the Tagged Image File Format (.tiff) raster file format for elevation data. The extension supports both tiled and scanline TIFF files.

  1. When inputs have been provided and ready, click on the Generate Tiles button.

../_images/OGC-Ext_12_ready_generate.png

Note

The terrain mesh generation may take some time to load.

../_images/OGC-Ext_13_Generated_output_stage.png

Note

Generating a tile at the same latitude and longitude coordinates of an existing tile will resize the map tile, but not update its image texture.

  1. Verify your tile has been created in the stage by navigating to the Stage tab, clicking on the Geospatial prim, and hitting the F-key to focus on the tile.

../_images/OGC-Ext_14_Generated_output_hierarchy.png ../_images/OGC-Ext_13_Generated_output_stage.png

Note

You may not be able to see the tile, so try to zoom in and out. To help with rendering, follow the following steps.

  1. (Optional) In your viewport, select the Perspective camera and select the three-slider icon to the right of Perspective.

../_images/OGC-Ext_16_perspective_camera.png
  1. (Optional) In the Properties tab, increase the far clipping range value. You can multiply the value by inserting a zero (0) before the decimal (.) point (i.e., “100000000.0” becomes “1000000000.0”).

../_images/OGC-Ext_15_increase_far_clipping_range_add_0.png

Congratulations! You have generated a map tile!

Release Notes

1.1.0-1

  • Custom URL - added fields for imagery and elevation for the user to query from desired servers and provide authentication

  • Scaling of map tiles - scaled up by 100,100,100 to convert meters to units to match scale of Omniverse assets

  • UI update, styles - default button and lat/long and northing/easting labels’ styles

  • UI bug, vertical scrolling - when scrolling downwards window will “bounce back” upwards when trying to scroll downwards to

  • File and tile naming - add increments as old convention of creating a new tile with same lat/long coordinates as an existing one will cause the old tile to be overwritten

1.0.9

  • Linux build code merges and switch to Kit SDK 104.0

1.0.8

  • Updated UI for beta release in Create 2022.2.1; user definitions of OGC API compliant servers

1.0.5

  • Extension beta release for Create 2022.2.0

Known issues

Map Tile Issues

  • Using relative file paths for the Image Download Directory field causes errors. Workaround is to provide an absolute path of an existing folder with user read-write permissions.

  • Generating small tiles (about 1km by 1km) will cause a “drooping” effect.

Future Work

  • Query for vector tiles for imagery, elevation, and features (e.g., buildings)

  • Auto-generation of map tiles based on position of camera

  • Curvature of map tiles

  • Swapping between Levels of Detail (LODs) for map tiles as user zooms in