3D Topography

Introduction

3D Topography is a utility to generate 3D-printable models from a global digital elevation model (DEM).

Data source

The DEM can be input with a GeoTIFF file or a latitude-longitude bounding box. If a bounding box is provided (either manually or via the interactive map), a query is sent to the OpenTopography API to retrieve the corresponding DEM.

The OpenTopography API provides an interface to a range of global raster datasets. 3D Topography uses the SRTMGL3 DEM (see also). This dataset covers the majority of Earth and has an approximate resolution of 3 arc-seconds (i.e., depth samples are spaced ~90m apart).

How it works

3D Topography expects a DEM encoded as a 2D-array of depth values. When spaced by the resolution of the dataset, this array can be visualised in 3D as a point cloud. 3D Topography then triangulates this point cloud in-browser, generating a collection of triangles that can be rendered to the screen or exported in the 3D-printable STL format.

The following is a 3D model of Uluru, generated from uluru.tif. The point cloud retrieved from the GeoTIFF file is shown on the left, and the corresponding triangulated model is shown on the right. The base of the model is at sea level.