Planet Generator and Runtime Shader

Planet Generator guides the user through five editor stages: heightmap generation, biome generation, cloud map generation, surface setup, and texture export.

The package contains:

• The PlanetGeneration.prefab entry point and PlanetGeneration component.
• The HeightmapGenerator, BiomeGenerator, and CloudmapGenerator components for generating maps.
• The PlanetSurfaceGenerator component and URP shader for previewing the configured surface on a planet model.
• The PlanetTexturesGenerator component for exporting a URP Lit material and texture maps.
• Preview materials and shaders used by the generation stages.

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1. Open Heightmap and press Generate. The generated map is assigned to Planet Generation. Save to File is optional when a standalone heightmap asset is needed.
2. Open Biomes and press Generate.
3. Open Clouds and press Generate.
4. Open Surface, configure the surface, and press Apply Changes.
5. Open Export, press Generate URP Lit Material, and select a folder inside the project's Assets directory.

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- HeightmapGenerator builds a deterministic procedural heightmap from its seed and detail settings. `Map Resolution` sets the map width; the output is equirectangular at a 2:1 width-to-height ratio.

- BiomeGenerator derives biome weights from the heightmap and its temperature and moisture settings. The generated biome map is assigned to Planet Generation.

- CloudmapGenerator generates a cloud coverage mask from its seed, resolution, coverage, scale, detail, and shape settings. The generated cloud map is assigned to Planet Generation.

- PlanetSurfaceGenerator combines the heightmap, biome map, cloud map, sea level, and configured surface textures and colors for the planet preview. Realtime Preview applies changes as settings change; Apply Changes explicitly applies them.

- PlanetTexturesGenerator exports Planet_URPLit.mat, Planet_BaseMap.png, Planet_HeightMap.png, Planet_NormalMap.png, and Planet_MetallicOcclusionSmoothness.png for URP Lit.