Created
December 28, 2018 13:30
-
-
Save 0scarB/7a08c188d57e3bf3d5c164f7a1c9c32e to your computer and use it in GitHub Desktop.
paper.js sketch that generates trees with branches of varying length.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| var width = view.size.width; | |
| var height = view.size.height; | |
| var averageLengthFac = 0.7; | |
| var angleInc = Math.PI/4; | |
| var iterations = 12; | |
| function drawLine(x1, y1, x2, y2, color) { | |
| var line = new Path(new Point(x1, y1)); | |
| line.strokeColor = color; | |
| line.add(new Point(x2, y2)); | |
| } | |
| function getNextBranchX(branch) { | |
| var x = branch[0]; | |
| var length = branch[2]; | |
| var angle = branch[3]; | |
| return x + Math.cos(angle)*length; | |
| } | |
| function getNextBranchY(branch) { | |
| var y = branch[1]; | |
| var length = branch[2]; | |
| var angle = branch[3]; | |
| return y + Math.sin(angle)*length; | |
| } | |
| function getBranchColor(branch) { | |
| var length = branch[2]; | |
| var angle = branch[3]; | |
| return new Color(angle/(2*Math.PI), 1 - angle/(2*Math.PI), 1 - length/startLength); | |
| } | |
| function drawBranch(branch) { | |
| var x = branch[0]; | |
| var y = branch[1]; | |
| drawLine( | |
| x, y, | |
| getNextBranchX(branch), | |
| getNextBranchY(branch), | |
| getBranchColor(branch) | |
| ); | |
| } | |
| function drawBranches(branches) { | |
| for (var i = 0; i < branches.length; i++) { | |
| drawBranch(branches[i]); | |
| } | |
| } | |
| function getRandomStandardNormalDistribution() { | |
| var x = 2 * Math.random() - 1; | |
| if (x < 0) { | |
| return -1/(Math.sqrt(2)*Math.PI)*Math.pow( | |
| Math.E, -0.5*Math.pow(x, 2) | |
| ); | |
| } | |
| return 1/(Math.sqrt(2)*Math.PI)*Math.pow( | |
| Math.E, -0.5*Math.pow(x, 2) | |
| ); | |
| } | |
| function getNextBranch(branch, nextAngle) { | |
| var nextX = getNextBranchX(branch); | |
| var nextY = getNextBranchY(branch); | |
| var nextLength = branch[2]*(1 + getRandomStandardNormalDistribution())*averageLengthFac; | |
| return [nextX, nextY, nextLength, nextAngle]; | |
| } | |
| var startLength = height/8; | |
| var groundY = 3*height/4; | |
| var branches = [[width/2, groundY, startLength, -Math.PI/2]]; | |
| var background = new Path.Rectangle(view.bounds); | |
| background.fillColor = 'black'; | |
| var ground = new Path.Rectangle( | |
| new Point(0, groundY), | |
| new Size(width, height - groundY) | |
| ); | |
| ground.fillColor = new Color(0, 0.5, 0.5); | |
| for (var i = 0; i < iterations; i++) { | |
| drawBranches(branches); | |
| if (i != iterations - 1) { | |
| var nextBranches = []; | |
| for (var j = 0; j < branches.length; j++) { | |
| var branch = branches[j]; | |
| var angle = branch[3]; | |
| nextBranches.push(getNextBranch(branch, angle + angleInc)); | |
| nextBranches.push(getNextBranch(branch, angle - angleInc)); | |
| } | |
| branches = nextBranches; | |
| } | |
| } |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment