The Ultimate Gas Giant Rendering System

This asset is designed to work in Unity 2021 LTS, Unity 2022 LTS, Unity 2023, and Unity 6, with the Built-In Render Pipeline, URP, and HDRP.

This asset includes a volumetric atmosphere and cloud system, and a fluid simulation system. All example scenes are in the "Plugins/CW/Gas Giant Forge/Scenes" folder. These show you what fully configured gas giants look like.

Fly From Space

Through The Rings

Through The Gas Giant

Realtime Fluid Simulation

Required Packages

Your project must have the Burst and Mathematics and Collections packages installed.

Package Installation Guide

Open: Window / Package Manager

Install Package: Burst

Install Package: Mathematics

Install Package: Collections

Making Your Own Gas Giant

There are two types of gas giants in Gas Giant Forge:

1. Full Fluid Sim - The whole gas giant surface is one big fluid simulation.

2. Slices - The gas giant is made from thin bands/slices of static textures and small fluid simulations.

Both gas giant types are fundamentally the same. The Full Fluid Sim gas giant just has one large fluid sim band/slice, whereas Slices comes pre-configured with many bands/slices. Both can be fully customized.

Full Fluid Sim

Example of a Full Fluid Sim gas giant.

To make your own gas giant from scratch, you can either:

• Right click in the Hierarchy tab, and select "CW / Gas Giant Forge / Gas Giant (Full Fluid Sim) (Radius = 500)".

• Go to the menu bar, and select "GameObject / CW / Gas Giant Forge / Gas Giant (Full Fluid Sim) (Radius = 500)".

This will create a new GameObject called "Gas Giant" with 2 child GameObjects:

• The "Sky" GameObject has the SgtSky component, which handles rendering of the core atmosphere of the gas giant. More info HERE.

• The "Sky" GameObject has the SgtShadowSphere component, which casta shadows from the gas giant onto the rings. More info HERE.

• The "Cloud" GameObject has the SgtCloud component, which handles rendering of the high altitude clouds that swirl around. More info HERE.

• The "Cloud" GameObject has the SgtCloudBundle component, which is a texture atlas that stores all gas giant bands/slices. More info HERE.

• The "Cloud" GameObject has the SgtGasGiantFluid component, which runs a fluid simulation that is rendered on the gas giant. More info HERE.

• The "Rings" GameObject has the SgtRingSystem component, which renders volumetric rings around the gas giant. More info HERE.

• The "Ring" GameObject has the SgtRingParticles component, which renders small asteroid particles inside the volumetric rings. More info HERE.

• The "Ring" GameObject has the SgtShadowRing component, which casts shadows from the rings onto the planet. More info HERE.

The gas giant surface is updated using a fluid simulation. To modify its settings, select the "Cloud" GameObject, and change the SgtGasGiantFluid component's settings. To quickly see results from your changes, you can click the "Step Simulation x1000" setting.

The simulation settings are very sensitive, so I recommend changing them by small amounts like 10%.

Slices

Example of a Slices gas giant.

To make your own gas giant from scratch, you can either:

• Right click in the Hierarchy tab, and select "CW / Gas Giant Forge / Gas Giant (Slices) (Radius = 500)".

• Go to the menu bar, and select "GameObject / CW / Gas Giant Forge / Gas Giant (Slices) (Radius = 500)".

This will create a new GameObject called "Gas Giant" with 2 child GameObjects:

• The "Sky" GameObject has the SgtSky component, which handles rendering of the core atmosphere of the gas giant. More info HERE.

• The "Sky" GameObject has the SgtShadowSphere component, which casta shadows from the gas giant onto the rings. More info HERE.

• The "Cloud" GameObject has the SgtCloud component, which handles rendering of the high altitude clouds that swirl around. More info HERE.

• The "Rings" GameObject has the SgtRingSystem component, which renders volumetric rings around the gas giant. More info HERE.

• The "Ring" GameObject has the SgtRingParticles component, which renders small particles inside the volumetric rings. More info HERE.

• The "Ring" GameObject has the SgtShadowRing component, which casts shadows from the rings onto the planet. More info HERE.

The gas giant surface is made of many separate texture bands. To modify or add more bands, select the "Cloud" GameObject, and change the SgtCloud component's CoverageBands setting. Each band uses a texture from the CoverageBundle setting, which by default contains many different textures.

By default, the gas giant has a radius of 100 meters, and the clouds extend 10 meters above the surface. To adjust this, select the "Sky" GameObject, and change the SgtSky component's InnerMeshRadius and Height settings.

If you're not sure what Height value should be used, a good starting point is to make this 10% of your InnerMeshRadius setting.

The gas giant surface is colored using a portion of a color gradient. To modify this, select the "Cloud" GameObject, and change the SgtCloud component's Albedo settings. For example, the AlbedoVariationX/Y settings can be adjusted. You can also click the buttons to quickly modify them, like "Randomize Albedo Gradient Texture" or "Randomize Variation".

You can hover the mouse over any inspector setting, and it will tell you what it does.

Required Scene Components

Your main scene light must have the SgtLight component to calculate lighting on the atmosphere and clouds. When you create a new planet, this will automatically be added.

Your scene must have the SgtVolumeManager component to render the gas giants. When you create a new gas giant, this will automatically be added.

Your main camera must have the SgtVolumeCamera component to render the gas giants. When you create a new gas giant, this will automatically be added.