Virus simulation

This project is about a virus simulator with great visualization. You can also highly customize the settings of the simulation. Note that the idea came from 3Blue1Brown's video on Youtube.

Installation

First, clone the repository to your device.

git clone https://github.com/mirusz9/Virus-Simulation.git

After cloning the repository, install the dependencies with the Node Package Manager, which comes with node.js. Be aware that npm install installs the Dev-dependencies as well. If you don't need them, use npm install --only=prod instead.

# Installs dev-dependencies as well
npm install

# Doesn't install dev-dependencies
npm install --only=prod

Dependencies

These dependencies are required for the code to work.

• ejs
• express
• typescript

Developement dependecies

These are for better code editing and faster testing

• @types/node
• nodemon

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Usage

Npm scripts

The most important commands are preset by mirusz9. npm start just starts a webserver on port 3000. npm run start-with-nodemon does the same, but nodemon restarts the server every time a .js file is changed. Note that dev-dependencies are required to use this command. If you have changed some typescript files, you must first compile all the .ts files to .js. This can be done with npm run ts-compile.

# Starts the webserver
npm start

# Starts the webserver with nodemon (dev-dependencies are required)
npm run start-with-nodemon

# Compiles the typescript files to javascript
npm run ts-compile

Editing settings

The settings file is located here ./src/settings.ts. A basic documentation is found in the settings file. Scroll down for detailed description.

export default {
	fps: 30,
	popSize: 500,
	socialDistancing: 0,
	maxVel: 1,
	infectious: {
		range: 20,
		count: 1,
		probab: 0.05,
		duration: 5,
	},
};

Setting	Default value	Description
fps	30	Sets the refresh rate of the simulation. Note that the simulation is optimized for 30fps.
popSize	500	Sets how many cells are in the simulation. If you have a slower computer, a smaller population size is recommended.
socialDistancing	0	Sets how many cells out of the population size are trying to get as far as they can from others. This number cannot be bigger than the popSize.
maxVel	1	Limits the velocity of the cells. Given in pixels.
range	20	The radius an infected cell can sense others. If another cell is in the radius, there is some probability that the cell becomes infected.
count	1	Sets the number of infected cells at the start of the simulation
probab	0.05	The probability a cell gets infected if it is in the range of an infected cell. This must be a number between 0 and 1.
duration	5	The duration a cell is infected before becoming removed. This number is not counted in frames but seconds. At 30 frames a second this means 150 frames.

After editing the settings, make sure to save the file and compile it into JavaScript. This can be done with npm run ts-compile.

Running simulation

Before running the simulation, you need to start the server with npm start.

npm start

After starting the server, open your browser and go to http://localhost:3000/. The simulation starts immediately. If you want to run the simulation again, just reload the page. After you change any of the settings or files, restart the server with running the command npm start again.

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mirusz9, 2020