SimpleXTerrain vs Ymir

SimpleXTerrain is a free, MIT-licensed addon for procedural terrain generation in Godot 4 .NET using C#. Its node graph editor defines heightmaps, biomes, splatmaps, and scattered instances. Heightmap sources include Perlin, fractal, and Voronoi noise, radial shapes, splines, and images. Modifiers include levels, curves, slope masks, hydraulic and thermal erosion, terraces, beaches, ledges, and blur.

At runtime, the addon evaluates terrain chunks asynchronously on .NET background tasks around a moving camera, then streams heightmaps and control maps into Terrain3D regions. The documented workflow uses a Terrain3D node with a camera or character attached to a terrain streamer to build Godot scenes. Requirements are Godot Engine 4.6 or later in its .NET or Mono edition, .NET SDK 8.0 or later, and the Terrain3D plugin. Setup involves copying the addon into the project’s addons directory, rebuilding the C# solution, and enabling the plugin in Project Settings. Foliage and object scattering can generate placement data, but the feature is experimental. Some GPU-capable work has RenderingDevice compute helpers; the documentation identifies CPU evaluation as the reliable path.

Ymir is a node-based procedural terrain generator for Linux and Windows, with a graph workflow for constructing and exporting terrain. Nodes cover noise and shape generation, sculpting, filters, and thermal, hydraulic, and stream erosion. Erosion can use a mask and produce flow, wear, and deposition layers for later terrain work. Projects are stored as readable JSON in .ymir files, and node networks can be saved for reuse as .ymirsub subgraphs. Heightmaps export as 16-bit grayscale PNG, raw 16-bit R16, or 32-bit float EXR. The headless ymir-cli can build saved projects and export results; erosion runs on a GPU when available and otherwise falls back to the CPU. The editor requires a GPU with working Vulkan drivers on Linux, or Vulkan or DX12 drivers on Windows. Ymir is free software under GPL-3.0. Windows binaries are unsigned and prompt a first-run SmartScreen warning.