Inspired by the excellent video:
- https://www.youtube.com/watch?v=lS_qeBy3aQI
- (How to program a basic Physic Engine by Pezzza's Work)
This is a quick demo of the basic Verlet equations for object-motion, implemented in Rust + Bevy. Now also integrates Egui, an immediate-mode GUI with bindings for Bevy, to add some widgets.
Note - I did another version of this in Python/Kivy, but not surprisingly, it was only able to handle 100-150 balls without dropping framerate. The Rust/Bevy version handled 500+ balls at 60 FPS, that I've tested.
- Bevy 0.12/Rust 1.72.1
- egui 0.24/bevy-egui 0.24
- Verlet Engine
- multi-ball collisions working
- one circular constraint enabled
- gravity working its magic
- ball-release on timer (fairly slowly, or incoming balls smash previous ball)
- collision-damping funky, some popcorn-effects at times
- at 500 balls, holding at 60 FPS - I added some pre-collision filtering, anyway
- the FPS can handle more than 500 balls, but there's some other weirdness with that many, alas
- has a simple control-panel using Egui widgets
- sliders, to set ball-count/ball-radius/ball-release delay
- buttons, to pause/reset
- has basic Game State logic, cycled by GUI buttons
- upscaled GUI widgets, larger/more readable
- added WASM support, so it runs in the browser
- app too large, have to hit < CTRL>- a few times to see it
- WASM requires modifying one line - still working on a general static-asset strategy
Now that ball-radius is adjustable, I'll comment that there's no sanity-checking on size of balls versus pit - it's possible to fill up the pit. Per the license, management is not responsible for any burned-up CPUs.
- make app resize for browser-window
- change collision-logic to handle balls of different radius
- change balls to have different radii (sort done, the slider can be changed mid-release!)
- figure out how to spawn balls on timer, without instant collisions
- experiment with dampening, to get less "dynamic" collisions
- add static balls for pinball-effect
- add links for some chaining
- move more parameters to control-panel
You don't have to use release, but a debug compile, takes a few seconds
longer to load the background bitmap.
cargo run --release
