This page is about the site. For the software, start at What is TerraGear?; to run it, start at Installing TerraGear.

Where TerraGear sits

FlightGear is the flight simulator. TerraGear is the toolchain that builds the world it flies over. Most FlightGear users never touch it: they download prebuilt scenery or let the simulator fetch it as they fly. It matters to the people producing that scenery, and to anyone who wants terrain for a region, or at a fidelity, the standard scenery does not cover.

The toolchain depends on SimGear, the library FlightGear itself is built on, and lives in the same GitLab group.

What this site is for

One route: Build your first scenery tile: from installing the tools to terrain you can fly over, with the commands that were actually run and the numbers they actually produced.

The FlightGear wiki covers the entire simulator and carries far more material than this site ever will. It also, on this particular toolchain, disagrees with the repository in nine places that a newcomer walks straight into: catalogued here. Four of those were settled by building the tools and running them. The rest are questions for the project rather than facts anyone can look up, and they are marked as questions.

Every figure on this site comes from one build on one machine, recorded on the sources page down to the commit hashes and the raw logs. Where something has not been tested, the page says so instead of generalising.

What would improve it

The obvious gaps, in the order they would help:

Builds from other people. One machine, one square, one afternoon is a data point. A mountainous region, a machine with different cores, a different FlightGear; any of those would turn the timings into something you could plan against.
A Windows or macOS build that someone has actually done. The Docker route works everywhere; a native one is documented nowhere.
Answers to the open questions. Which branch a newcomer should build, whether the README should be updated or retired, whether there should be tagged releases. These need someone from the project, not more testing.
Corrections. Especially where this site and the wiki disagree. If this site is the one that is wrong, that is worth knowing quickly.

Code belongs upstream, at gitlab.com/flightgear/terragear. Three defects found while building for this site are described on Common errors and fixes.

Which channel suits which question (forum, mailing lists, issue tracker) is on Mailing lists, along with what became of TerraGear’s own two lists.