# aahdee-Intersections

 //defining constants const WIDTH = 720; const HEIGHT = 480; const BACK_COLOR = 'rgb(172, 230, 230)'; const NUM_LINES = 100; const LINE_LEN = 250; const LINE_COLOR = 'rgb(0, 86, 86)'; const LINE_STROKE = 2; const CIR_CIR = 12; const CIR_COLOR = 'rgba(11, 140, 140, 0.5)';   //global variables var pointList = []; var intsecList = [];   function setup() { createCanvas(WIDTH, HEIGHT); background(BACK_COLOR); angleMode(DEGREES); }   /* Lines functions. These are created by generating a random start point and slope and then uses trig to get the end points from that data.*/   function drawLine() { stroke(LINE_COLOR); strokeWeight(LINE_STROKE); var x1 = random(50, WIDTH-50); var y1 = random(50, HEIGHT-50); var angle = random(360); var endHeight = LINE_LEN*sin(angle); var endLength = LINE_LEN*cos(angle); var x2 = x1 + endLength; var y2 = y1 + endHeight; line(x1,y1,x2,y2); var linePoint = [x1,y1,x2,y2]; pointList.push(linePoint); }   //source for intersect formulas: http://paulbourke.net/geometry/pointlineplane/ function grabIntersects(points) { var x1 = points[0], y1 = points[1], x2 = points[2], y2 = points[3], x3 = points[4], y3 = points[5], x4 = points[6], y4 = points[7]; var den = ((y4-y3)*(x2-x1)) - ((x4-x3)*(y2-y1)); if (den != 0) { var ua = (((x4-x3)*(y1-y3))-((y4-y3)*(x1-x3)))/den; var ub = (((x2-x1)*(y1-y3))-((y2-y1)*(x1-x3)))/den; if (0 <= ua && ua <= 1 && 0 <= ub && ub <= 1) { var x = x1 + ua*(x2-x1); var y = y1 + ua*(y2-y1); intsecList.push([x,y]); } } }   function drawCircles() { noStroke(); fill(CIR_COLOR); while (intsecList.length != 0) { var points = intsecList.shift(); ellipse(points[0], points[1], CIR_CIR); } }   function draw() { setup(); for (var i = 0; i < NUM_LINES; i++) { drawLine(); for (var j = 0; j < pointList.length-1; j++) { grabIntersects(pointList[j].concat(pointList[pointList.length-1])); } } drawCircles(); pointList = []; intsecList = []; noLoop(); }   function mouseClicked() { redraw(); }