Star Definition

Altos includes a powerful and dynamic star system that gives you control over the appearance, flickering, size, and positioning of a star system that can feature tens of thousands of stars.

Overview

The star system is made up of a Compute Shader that renders the Count number of quad meshes, each rotated randomly, in a sphere around the camera. You can render any number of Star systems in a scene.

Usage

1. In the menu bar, click GameObject > Empty Game Object.
2. In the Inspector, click Add Component.
3. Search for Stars.
4. Add the Stars component to the Game Object.

Config

By default, the star system assigns a color and brightness value to each star in the sky. These values are based on a proprietary distribution model using scientific star brightness and color data.

You can use these values, you can tint the Color and Brightness, or you can ignore them altogether by unchecking the Automatic Color and Automatic Brightness options.

You can set any Texture as an input for the stars. The stars use an additive blend mode, so there's no need to enable transparency for the input texture.

You can set the Flicker Frequency and Flicker Strength. These values are also automatically adjusted near the horizon; stars appear to flicker more often at the horizon due to atmospheric attenuation.

You can set the Size. (We automatically distribute the stars in a range around the input size. This isn't configurable.)

From a positioning standpoint, the basic concept is that you are on the equator and true north is aligned with +Z axis. As a result, the stars rotate around the +Z axis. You can adjust the Inclination to tilt the stars, which adjusts the axis around which the stars will rotate.

The stars automatically make one full rotation each 24hr period. You can lock the stars in place by checking the Position Static checkbox.

Properties