//

// Generative Gestaltung – Creative Coding im Web

// ISBN: 978-3-87439-902-9, First Edition, Hermann Schmidt, Mainz, 2018

// Benedikt Groß, Hartmut Bohnacker, Julia Laub, Claudius Lazzeroni

// with contributions by Joey Lee and Niels Poldervaart

// Copyright 2018

//

// http://www.generative-gestaltung.de

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

​

/**

 * drawing with a changing shape by draging the mouse.

 *

 * MOUSE

 * position x          : length

 * position y          : thickness and number of lines

 * drag                : draw

 *

 * KEYS

 * del, backspace      : erase

 * s                   : save png

 */

'use strict';

​

function setup() {

  createCanvas(720, 720);

  noFill();

  background(255);

  strokeWeight(2);

  stroke(0, 25);

}

​

function draw() {

  if (mouseIsPressed && mouseButton == LEFT) {

    push();

    translate(width / 2, height / 2);

​

    var circleResolution = int(map(mouseY + 100, 0, height, 2, 10));

    var radius = mouseX - width / 2;

    var angle = TAU / circleResolution;

​

    beginShape();

    for (var i = 0; i <= circleResolution; i++) {

      var x = cos(angle * i) * radius;

      var y = sin(angle * i) * radius;

      vertex(x, y);

    }

    endShape();

​

    pop();

  }

}

​

function keyReleased() {

  if (keyCode == DELETE || keyCode == BACKSPACE) background(255);

  if (key == 's' || key == 'S') saveCanvas(gd.timestamp(), 'png');

}

​