// Author: Daniel Kaye

//  URL: http://dnkaye.com/2020_CodingChallenges.html

//

// Based on Daniel Schiffman's (Coding Train) coding challenges

//  URL: https://thecodingtrain.com/CodingChallenges/006-mitosis-p5.html

//  

// What is this?

//  An attempt to simulate cell mitosis, in some sense

//

// How do I do this?

//  I attempt to complete Daniel Schiffman's coding challenges before watching

//  his video, then afterwards I watch and see what he did differently, and learn!

​

// Things I'm proud of / differences from The Coding Train version:

//  -using polar coordiantes (angle) to set and change directions of travel of particles (cells)

//  -mitosis triggered by max size OR mouse press

//  -reversal of direction at screen edges using trig

//  -shrinking animation of cell during mitosis, sorta looks like they're actually splittling off from eachother

​

let cells = []; // array to hold all cells

let speed = 0.25; // appro speed at which cells move

let growthRate = 0.05 // approx growth rate for cells

let fullyGrownRadius = 25; // max size a cell will grow too before splitting

let maxNumOfCells = 1000; // program resets when there are more than 1000 cells (prevents creashing)

​

function setup() {

  createCanvas(400, 400);

  cells.push(new Cell(width / 2, height / 2, fullyGrownRadius * 0.75)); // creates first cell

}

​

function draw() {

  if (focused || frameCount < 30) {

    background(255);

    drawCells(); // draws, moves, and grows all cells

    // resets cells if there are too many (prevents crashing, sometimes)

    if (cells.length > maxNumOfCells) {

      resetCells();

    }

    drawNumOfCells(); // writes current number of cells to the screen

  } else {

    drawUnpauseInstructions();

  }

}

​

function drawUnpauseInstructions(){

  noStroke();

  fill(0);

  textAlign(CENTER);

  textSize(18);

  text('click to activate', width/2, height - height/5);

}

​

// draws all cells in array

function drawCells() {

  for (let cell of cells) { // for all cells....

    cell.grow(); // incrimentally grows each cell

    cell.move(); //incrimentally moves each cell

    cell.draw(); // draws cell to screen

    // cell starts mitosis if it's reached it's fully grown size

    if (cell.r >= fullyGrownRadius) { // if a cell has reaced it's maximum size....

      mitosis(cell); // split that cell

    }

  }

}

​

function mousePressed() {

  // if you click on a cell, start mitosis

  for (let i = 0; i < cells.length; i++) {

    if (cells[i].isHovered()) {

      mitosis(cells[i]);

      print('mitosis! ' + cells.length);

      i = cells.length;

    }

  }

}

​

// makes a cell split in two

function mitosis(cell) {

  cell.splitting = true;

  let newDir = cell.dir + PI; // new direction = opposite direction of cell it's splitting off of

  newDir += (random(0, PI / 2)); // slightly alters, randomizes new cell direction to make sketch appear slightly mroe organic

  if (newDir > 2 * PI) {

    newDir -= 2 * PI;

  }

  cells.push(new Cell(cell.x, cell.y, cell.r * 0.5));

  cells[cells.length - 1].dir = newDir;

}

​

// clears array of cells, starts a  new array with only one

function resetCells() {

  cells = [];

  cells.push(new Cell(width / 2, height / 2, fullyGrownRadius * 0.75)); // creates first cell

}

​

function drawNumOfCells() {

  noStroke();

  fill(192);

  textSize(14);

  textAlign(LEFT);

  text('number of cells: ' + cells.length, 10, height - 10);

}