Biomes are the animal and plant life, soil properties and other natural elements that you would expect in an outdoors area according to its climate - a desert biome consists of sand, cacti and scorpions for example.
When designing virtual landscapes with Gaia, Biomes can be used to collect spawners that fit well together into an overarching biome. To create an ice biome, you could collect an ice texture spawner, an icy rock spawner, a snowman spawner in an Ice World Biome. You can then either spawn this biome across the entire terrain, or only e.g. in the lower left corner of the terrain.
Grouping Spawners into a biome is also useful to apply a matching set of spawners to a new terrain quickly - with the click of a button a terrain can receive a certain look and feel since all the spawning rules will adapt to the new terrain surface.
Here is the same terrain, but populated with a different biome each:
The tool that holds those spawners together and controls where they spawn in the Game World is the Biome Controller:
Similar to an individual spawner, the biome controller has multiple panels that control its functionality. The following sections describe the panels one by one.
The Biome Settings panel holds some general settings for the biome, especially in regards to where it should be applied. The single settings are:
There are two buttons in the panel "Fit To Terrain" and "Fit to World". Similar to the spawners these buttons will fit the biome controller to the terrain it is positioned over, or over the entire world of this scene.
This panel contains a list of spawners that make up this biome. You can activate and deactivate single spawners of the biome with the checkboxes for each entry.
The Area setting on top of the list of spawners is especially important: "Local" means the biome will only spawn within the current position / spawner range, while "World" means the biome will automatically be applied across all terrains in the scene (masks still apply for both modes).
With the "Create New Spawner" button you can quickly create a new spawner in the scene that will automatically be added to this biome as well. Great when extending an existing biome.
The "Set up in Stamper" button will copy the spawners from this list over to the "Autospawners" list in the Stamper in the scene - in this way you can stamp and automatically trigger the biome spawners afterwards. See the article page on the stamper for details.
The Advanced Panel is home to multiple sub-panels, each of which control more advanced features of the biome controller.
Add Post Processing Volume: Allows you to add a post processing volume at the position / size of the biome controller. (Built-In Rendering Post Processing). This can be useful if you want to override post processing settings on certain areas of your world, matching the underlying biome.
Appearance: Holds settings related to Terrain Loading (Gaia Pro) and display of Scene View Gizmos.
Remove Assets from other Biomes: Allows you to create the biome areas from "Foreign" Biomes within the valid spawn area of this Biome. Imagine you start with spawning assets across the entire terrain, but later on you decide you want to spawn a desert biome in the center. With the feature in this panel you can clear out all "foreign" trees, grasses etc. from your desert zone so that only assets from your desert biome remain in this area.
Save and Load - Allows you to save the biome controller settings as a biome file - which you then can re-use in other projects / scenes.
Allows you to remove previously spawned object types, either only from this biome only, or from all biomes, and you can decide whether the deletion should be applied to a single terrain only or to all terrains in the scene.
Last but not least there are two control buttons at the bottom of the spawner:
"Spawn Biome" will spawn the biome in either "Local" or "World" mode, depending on the "Area" setting in the list of spawners.
"Create Runtime" is a shortcut button to create the current Runtime Setup as configured in the Gaia Manager at that moment.