Gaea Documentation
The documentation is being updated for version 1.3. Some sections may be incomplete.

Rivers can instantly generate complex river networks on any terrain, whether it can sustain rivers or not. The node subtly transforms the terrain to provide unbroken pathways for a river to be generated.

Generating rivers does not require many prequisites. The terrain should just have some slopes, so rivers can flow downslope. This makes Rivers very versatile as you can use it with virtually any terrain shape and at almost any stage of your terrain's production.

While the rivers are generated for you using sophisticated algorithms that closely mimic nature, you can still retain a fair level of control over the rivers. By providing a Headwaters mask, you can confine all starting headwaters inside that mask. All rivers would then originate from those locations, giving you artistic control over river generation while leaving the minute details to the algorithm.

You can even use Rivers early in your graph to help carve pathways and valleys for ancient rivers that have dried up, or for river generation later in the graph. In the latter scenario, having a River early in the graph helps the Erosion and other effects take the river pathway into account throughout the terrain production. See the Quickstart "Enclosed River" for an example.

Rivers and Lakes can work together to create a comprehensive water element for your terrains. See the Quickstart "Rivers and Lakes" on how to combine them and produce colors from the combined water depth.


HeadwatersThe number of headwaters from which rivers can start. Not all will become rivers, but rather tributaries that feed the main river.
WaterThe amount of water in headwaters. Higher values can create larger rivers.
WidthThe width of the rivers. High values create wide rivers, with somewhat wide tributaries. Low values create thin rivers with thin tributaries.
DepthThe depth of the rivers. This value is independent of Downcutting.
DowncuttingLike with the Erosion node, Downcutting decides how deeply the river should cut into rock and soil while moving forward.
Render water surfaceCreate a water surface for the rivers. This can be used directly in the terrain, especially when you have wide rivers, or export it as a separate heightmap for further river production in your CG application or game engine.
SeedThe randomization pattern or seed for the node's process.
Lakes Sea