Bouncing Ball Project

This is a simple project built with React that uses mouse drag and release to throw balls.

Demo Video

Ball Bounce Demo Video

Ball Bounce with Web Workers Demo Video

Features

Ball Bounce

1. Drag and release to throw a ball, the cursor speed will determine the initial speed of the ball.
2. There are two balls by default, when a ball collides another, the two balls makes inelastic collision.
3. When a ball collide with the wall, inelastic collision happens and the speed of the ball decreases.

Ball Bounce with Web Workers

0. Webworkers mounted when component loads.

1. Specify amount of ETH prices you wish to fetch. (Just using ETH price for demo purpose)

2. When Fetch New Price button is pressed, web worker randomly generates amount of prices specified in the input field and sorts it.

   2-a. Sorting is a O(nlogn) calculation, if you set the number to something very large (eg. 10^6), you will better see the effects of the web worker.

   2-b. While webworker is sorting, try bouncing the balls.

3. Web worker returns five lowest price to the main thread. The ball bounces on the main thread does not get blocked even during heavy calculations.

4. Webworkers cleaned up when component is unmounted

Other Possible Features for Ball Bounce

• Provide the selection of ball masses
• Change number of balls
• Select type of collision (elastic / inelastic)
• Add "friction" when sliding, make speed reduce even without collision
• Add ball bounce while being dragged
• Add more UI

Code Explanation

Ball Bounce

• function Ball component draws a Ball on the page
  • it takes color, initial position, and size as argument
  • a div with set styles are returned
• custom hook useDraggableBall manages state and behavior related to draggable balls
  • it manages states and behaviors of the ball such as position, velocity, dragging state, wall collision detection (Wall Collision is inherent in each balls, therefore it is included here rather than App.js)
• Main App Component
  • instantizes state and behavior of the draggable balls with useDraggableBall custom hook
  • based on position of the two balls, handle ball to ball collisions
  • include event handlers (onMouseDown, onMouseMove, onMouseUp) for mouse interactions

Available Scripts

In the project directory, you can run:

npm start

Runs the app in the development mode.
Open http://localhost:3000 to view it in your browser.

The page will reload when you make changes.
You may also see any lint errors in the console.

npm test

Launches the test runner in the interactive watch mode.
See the section about running tests for more information.

npm run build

Builds the app for production to the build folder.
It correctly bundles React in production mode and optimizes the build for the best performance.

The build is minified and the filenames include the hashes.
Your app is ready to be deployed!

See the section about deployment for more information.

npm run eject

Note: this is a one-way operation. Once you eject, you can't go back!

If you aren't satisfied with the build tool and configuration choices, you can eject at any time. This command will remove the single build dependency from your project.

Instead, it will copy all the configuration files and the transitive dependencies (webpack, Babel, ESLint, etc) right into your project so you have full control over them. All of the commands except eject will still work, but they will point to the copied scripts so you can tweak them. At this point you're on your own.

You don't have to ever use eject. The curated feature set is suitable for small and middle deployments, and you shouldn't feel obligated to use this feature. However we understand that this tool wouldn't be useful if you couldn't customize it when you are ready for it.