- Create a particle-system representation of Saturn Rings.
- Use THREE.js as inteface to WebGL.
- Emphasize use of shaders and technologies studied.
- Summary study on efficiency of application.
A well and examples fully documentation si available here: Three.js
- Like Jupiter, is a Giant Planet: it’s the second biggest planet of our solar system.
- It’s largely composed by hydrogen and helium: it’s a gased planet.
- It has 88 moons and 16 rings. These rings are composed by debris and dust.
- It has a revolution period of 29 years and a day of 10 hours.
On this context we apply some semplifications on this enormous system:
- Saturn is represented with 2 rings and 1 moon, Titan.
- Collisions betweendebrisaretrascured.
- Shapes of Saturn and Titano are rounded as spheres.
- Omitting Y dimension, the orbit of a single paritcle can easly be described by a formula like:
- x = A*cos(t)
- z = B*cos(t)
- Unfortunately, using formula like that for every verticies means positioning all in the same point.
- The result would be a single particle moving on elliptic orbit.
- A solution may be introduce a constant different for evry verticies. Orbit formula can be rewrite as:
- x = A*cos(base + t)
- z = B*cos(base + t)
- Now all particles are disposed in different points of orbit: they compose a ring.
- It’s not enought: every particle need a certain freedom degree.
- To reach that purpose offsets on X and Z axis are now introduced.
- These offsets move out the particle from the “main” orbit.
- With right bounds on offsets, the resulting effect is something like a streched ring.
- Ending, orbit formula will be like:
- x = (A + offsetX)*cos(base + t)
- z = (B + offsetZ)*cos(base + t)
It’s not easy to evaluate performances of a system strongly based on hardware design and software optimization. It’s only possible make some considerations:
- Using a MacBook Pro Retina (2,4 GHz Intel Core i5, Intel Iris 1536 MB) and Safari as reference, were observed results below:
