Tyvan-Intersections<br>

var numLines = 12;

var dia = 20;

var xOne, yOne, xTwo, yTwo;

var lines = [];

var inters = [];

​

// Properties related to whole document

function setup() {

    createCanvas(720, 480);

    noLoop();

    ellipseMode(CENTER);

}

// Starts the first session

function draw() {

    mousePressed();

}

​

// Refreshes everything on click

function mousePressed() {

    background(235, 254, 240);

    lines = [];

    inters = [];

    for(i = 0; i < numLines; i++) {

        generateLine();

    }

    drawLines();

}

​

// Places x, y coordinates into matrix

function generateLine(){

    var line = {

        x1: random(width),

        y1: random(height),

        x2: random(width),

        y2: random(height),

    }

    lines.push(line);

}

​

function drawLines() {

    // Iterates through matrix of coordinates

    for(i = 0; i < numLines; i++){

        var x1 = lines[i].x1;

        var y1 = lines[i].y1;

        var x2 = lines[i].x2;

        var y2 = lines[i].y2;

        for(j = 0; j < numLines; j++){

            var x3 = lines[j].x1;

            var y3 = lines[j].y1;

            var x4 = lines[j].x2;

            var y4 = lines[j].y2;

            LineIntersect(

                x1, y1, x2, y2, x3, y3, x4, y4);

        }

        strokeWeight(1);

        line(x1, y1, x2, y2);

    }

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

        mx = inters[i][0];

        my = inters[i][1];

       strokeWeight(0);

       fill(255, 220, 220, 200);

       ellipse(mx, my, dia, dia);

    }

}

​

​

// Function adapted from Paule Bourke

// http://paulbourke.net/geometry/pointlineplane/pdb.c

function LineIntersect

(x1, y1, x2, y2, x3, y3, x4, y4) {

   var mua,mub;

   var denom,numera,numerb;

   var tru;

​

   denom  = (y4-y3) * (x2-x1) - (x4-x3) * (y2-y1);

   numera = (x4-x3) * (y1-y3) - (y4-y3) * (x1-x3);

   numerb = (x2-x1) * (y1-y3) - (y2-y1) * (x1-x3);

​

   var mx;

    var my; 

​

    if (abs(denom) > 0){

   /* Is the intersection along the segments */

   mua = numera / denom;

   mub = numerb / denom;

   if (mua < 0 || mua > 1 || mub < 0 || mub > 1) {

      return;

   } else {

        mx = x1 + mua * (x2 - x1);

        my = y1 + mua * (y2 - y1);

        inters.push([mx, my]);

   }

    }

}

​

​

​