Procedural Planet Generation: Shaders, In-Editor Baking & Custom Space Lighting

March 2026: New 1.3.0 Update - Asteroid Belts:
Procedural asteroid shaders combined with instancing for real-time rendering of 1000s of asteroids with animated orbit and rotation. Custom instancing LOD system with sphere meshes for maximum performance.

Feb 2026: New 1.2.0 Update - Gas Giant Fluid Simulations with Curl Noise:
New custom solution with custom render texture and curl flow materials to simulate realtime gas giant flow - with bands, turbulence and large spherical storms. This technique is performant at runtime and allows for truly unique and natural-looking gas giant patterns that you can't get with simple procedural shader noise distortions.

Procedural Planet Generation is a Unity framework for creating procedural celestial bodies through shaders with editor tools for texture baking and scripts for in-editor and runtime procedural generation. Generate stars, gas giants, asteroid rings, moons, and Earth-like planets with customisable properties and randomization ranges.

This framework is NOT for landable planets - it generates spherical textures and shaders to be viewed from orbit or in solar system maps.

Built with Shader Graph, VFX Graph, and Render Graph, this framework creates beautiful and detailed, lightweight, non-landable planets optimized for viewing from space. This is NOT a terrain generation tool for landable planets - it focuses on procedural surface shaders, texture generation, and visual effects rather than geometric terrain, mesh generation, or raymarching. It's perfect for space strategy games, solar system maps, background environments, and skyboxes.

No AI is used in this framework - all the shaders are fully procedural and hand-built.

Core Features
- Editor Procedural Generation: Custom inspector UI lets you generate and randomize celestial bodies in the Editor, with undo/redo support. Each celestial body shader is paired with a custom control script using a modular component architecture that's easy to modify and extend.
- Runtime Generation: All procedural generation functionality is also available at runtime through callback functions, allowing you to create dynamic solar systems and randomized space environments in-game.
- Customizable Randomization Ranges: Define property ranges and color palettes for procedural generation to create random planets within your artistic guidelines. Keep stars within the blue-white-yellow-red spectrum for realism, or go fully fantastical with exotic colors. Control ranges for every parameter, from continent size for Earth-like planets to crater density for moons, and more.
- Static Texture Baking: Bake your procedurally generated planets into static textures to eliminate the performance cost of complex shader functions while maintaining visual quality. Contains editor tools for color and heightmap baking. Custom support for cubemaps retains 1:1 parity in visuals between procedural shaders and static texture rendering. Flowmaps enable static textures to display dynamic flow effects for stars and gas giants.
- Custom Space Lighting System: Custom shader-based lighting solution provides omnidirectional space lighting for scenes with multiple planets and a single star light source, like in solar system maps. Includes shadow support for single spherical occluders - cast shadows on asteroid rings from their parent planets, or simulate Earth casting shadows on the Moon and vice versa.
- Extensive Artistic Control: These customizable shaders give you fine-grained control. Create realistic Earth-like blue-and-green worlds, desert planets with green oceans, or fantastical alien worlds.

Procedural Shader Graph Shaders List:
- Moons: Cratered and creviced surfaces with procedural detail and heightmap-adjusted color gradients.
- Earth-like Planets: Continents and ice caps form landmasses with procedural surface normals - mountains, ridges, and coastlines. The heightmap samples a color gradient to create natural-looking terrain patterns. Oceans feature shallow and deep water regions. Fresnel and post-processing glow for atmospheric effects.
- Gas Giants:
- Curl flow simulation - complex fluid-like simulation with custom render textures.
- (Legacy) dynamically swirling cloud bands and moving spherical storms. Fresnel and post-processing glow for atmospheric effects.
- Gas Giant Rings: Spherically banded and rotating disc regions with variable alpha creating dynamically transparent areas and density variations.
- Asteroid Belts: Custom instancing solution with vertex displacement shaders and runtime orbit and rotation animations.
- Stars: Dynamically flowing molten star surface made luminous with glow effects and post-processing bloom, smoky edge corona with VFX Graph particles.
- Space Skybox VFX Graph: Includes the VFX Skybox from the Procedural Space Skybox asset - a simple and lightweight VFX Graph skybox perfect for space environments.

Advanced Visual Features
- Procedural Normal Mapping: Craters, ridges, mountains, and continental coastlines for Earth-like planets are converted to a heightmap and sample procedurally or bakeable to cubemap textures. Cubemap textures are then sampleable through custom cubemap normal sampler shader functions integrated into all shaders.
- VFX Graph Integration: Star corona edge effects and VFX Skybox are implemented with VFX graph, paired with control scripts for randomization.
- Render Graph Post-Processing: Custom atmospheric and star glow effects with Fullscreen Shaders using Unity's Render Graph.