Overview

Geopipe models are georeferenced to real-world coordinates. This means that you can use them in conjunction with other geospatial data, such as OpenStreetMap data, to create a data-rich environment for gaming and simulation. We recommended using a georeferencing plugin for your game engine or 3D modeling software to ensure that your model and data are georeferenced correctly.

Reference Point

Included in each download is a metadata.txt file with information about your download. The two lines that begin with S2 base point and Geographic base point define the origin (0,0,0) point for the model. The Geographic base point is the latitude, longitude, and altitude above the ellipsoid as defined by the WGS84 standard. The S2 base point refers to an ellipsoidal S2 coordinate system. We recommend using PROJ and its quadratic transformation to convert the S2 point to other coordinate systems. If you have any further questions about using our base points, feel free to contact us.

Example

The following sample comes from a metadata.txt file.

S2 base point: s = 0.042419, t = 0.681671, face = 4.000000, up = 0.000000
Geographic base point: 40.718879, -74.027075 altitude 0.000000

In the S2 system, the origin point is at s=0.042419 t=0.681671 on S2 face 4 and 0.000000 meters above the surface of the ellipsoid.

The latitude-longitude coordinates of the origin point are (40.759337, -73.962433), and 0.000000 meters above the WGS84 ellipsoid at that coordinate.