Introduction

Example terrain image.

What is a “terrain system”?

A “terrain system” is a system that defines the geometry, color, and surface types for a ground surface. More specifically, a terrain system contains:

Height, color, and surface data mapped to regions of the world
Authoring tools and workflows that support creating / modifying data and mapping it to regions
Queryable data that can be used by both simulation and rendering
Specialized rendering as needed to support efficient, high-quality terrain visualization across the view distance
One or more physics surfaces that can provide a “physical” simulation of the terrain in the virtual world

Design tenets

The O3DE terrain system was built with specific design tenets in mind. Enhancements and changes to the system should continue to use these tenets as guiding principles:


Enjoyable	Content creators and engineers are delighted to use the terrain system and excited by the power and flexibility the tools provide.
Familiar	The design is familiar to content creators that use external terrain authoring tools and should follow similar design patterns used in other O3DE workflows.
Fast	Iteration is rapid and responsive, and the runtime is optimized to a production-ready state.
Reusable	Every aspect of the system is optional, reusable, and replaceable, and the system reuses existing functionality in O3DE as much as possible. Content is authorable as optional, reusable, and replaceable pieces.
Scalable	The system scales to allow for worlds of arbitrary size and density without enforcing any hard limits.
Dynamic	Portions of the terrain are dynamically loadable, unloadable, and modifiable at runtime.

Note that Simplicity is not a design tenet. While we should always strive for simplicity, we also acknowledge that we’re accepting an initial learning curve for the sake of the other tenets.

Design goals

The terrain system adheres to the following design goals:


Workflow parallelization	Multiple content creators can work on different terrain locations or different aspects of the terrain content at the same time.
System / workflow reuse	The terrain system leverages the existing Shape components, Surface Data components, Gradient Signal components, Landscape Canvas system, and the entity/component authoring workflows.
Data flow transparency	Source data exists as external assets in common editable formats that hot-reload when changed. The output data used in the game should always be in sync with the inputs and traceable back to them.
Non-destructive editing	Terrain data is modifiable either through layered changes or through direct data changes that don’t require the original source data to change.
Round-trip data flows	Terrain data changes are easy to export to external content tools. The data can be modified further and re-imported.
Reusable data	The same terrain data is reusable for multiple different locations in the world.