# 11. TopographyMap: elevation in absolute numbers

TopographyMap includes the following models: `digital elevation, hillshade, slope, aspect, relief position, roughness, ruggedness`, and their combination. The representation is available on the field level accurately (not pixelated) and cropped by the boundary. The quality of topography depends on the field location and the best available dataset (USA, GB, EU, and AU are covered with LIDAR). TopographyMap can be built out of machinery data like yield/soil sensors/as applied datasets if they contain elevation attributes inside. 

Field topography-related data layers are located in the `field` -> `topographyMaps` -> `geoMaps` attribute. Every `geoMap` contains complete details about the access `url`, color codes, classes, and layer names.

<figure><img src="https://3272281156-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FYICBELdyAXXebKAzfLOR%2Fuploads%2FkBBhURFR90kOC9tlXero%2Fimage.png?alt=media&#x26;token=caa9d402-aee7-47e8-b5eb-e36085259656" alt="" width="563"><figcaption><p>LIDAR elevation</p></figcaption></figure>

<figure><img src="https://3272281156-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FYICBELdyAXXebKAzfLOR%2Fuploads%2Fe01cIvD7QPwzIBpAkLM6%2Fimage.png?alt=media&#x26;token=40be0b28-6fab-477d-ab2f-4d8d2491f637" alt="" width="563"><figcaption><p>LIDAR slope</p></figcaption></figure>

<figure><img src="https://3272281156-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FYICBELdyAXXebKAzfLOR%2Fuploads%2Fm2MjuJAUohqKPFXNl4YJ%2Fimage.png?alt=media&#x26;token=50130bed-164a-4af3-a451-2b9766af0d6f" alt="" width="563"><figcaption><p>LIDAR relief position</p></figcaption></figure>

The request format is [https://api.geopard.tech/geo/map/reflect?TRANSPARENT=true\&BBOX=\<minX,minY,maxX,maxY>\&LAYERS=elevation\_cropped,field\_view\&STYLES=dem\_elevation,crop\_boundary\&SRS=EPSG%3A900913\&WIDTH=512\&env=ve1:160.4%3Bve2:163.15%3Bve3:165.9%3Bve4:168.65%3Bve5:171.4\&VIEWPARAMS=uuid:\<field\_uuid>\&CQL\_FILTER=uuid=%27\<topography\_map\_uuid>%27%3Buuid=%27\<field\_uuid>%27\&geopardApiKey=\<geopard\_api\_key>](https://api.geopard.tech/geo/map/reflect?TRANSPARENT=true\&BBOX=). Where the input attributes are:

1. `BBOX=<minX,minY,maxX,maxY>` contains the bounding box (url encoded) of the  "Field" in EPSG:3857 projection;
2. `STYLES=dem_elevation,crop_boundary` contains the style of the "TopographyMap" entity as a first attribute, its supported values are:

`dem_aspect`

`dem_elevation`&#x20;

`dem_hillshade`

`dem_roughness`

`dem_slope`&#x20;

`dem _tpi`

`dem_tri`

3. `WIDTH=512` reflects the output image size in pixels (the precise number is important only if it is used as a thumbnail);
4. `env=ve1:160.4%3Bve2:163.15%3Bve3:165.9%3Bve4:168.65%3Bve5:171.4` reflects the range of elevation values for the particular field, the details are located in the "TopographyMap" -> "geoMaps" -> "classes" (NOTE: %3B is url encoded ; symbol);  &#x20;
5. `VIEWPARAMS=uuid:<field_uuid>` contains uuid of the "Field";
6. `CQL_FILTER=uuid=%27<topography_map_uuid>%27%3Buuid=%27<field_uuid>%27` contains the UUIDs of the "Field" and "TopographyMap" (NOTE: %27 is url encoded ‘ symbol) ;
7. `geopardApiKey=<geopard_api_key>` is coupled to the authorization option via API Key.