breep-Scope

My design largely stemmed off the idea of conveying circles within circles. I wanted to show how the movement of the black circle within the larger unit conveys the movement of a larger black circle that is made by the sum of its parts. This was a notion that I wanted to explore in my gif, but never really got round to integrating it, so this was a kind of nod to that idea.

/*
// Template for KidzLabs/4M/Toysmith Animation Praxinoscope
// https://www.amazon.com/4M-3474-Animation-Praxinoscope/dp/B000P02HYC
// https://www.walmart.com/ip/Animation-Praxinoscope-Science-Kits-by-Toysmith-3474/45681503
// Developed for p5.js, September 2018 * Golan Levin 
 
*/
 
 
 
var inch = 72.0; 
var diamArtInner = inch * 1.50; 
var diamArtOuter = inch * 4.80; 
var diamCutInner = inch * 1.41; 
var diamCutOuter = inch * 4.875; 
var holeDy = inch * 0.23;
var holeDx = inch * 0.20;
var holeD = inch * 0.1;
 
var nFrames = 10; 
var myFrameCount = 0;
var exportFrameCount = 0; 
 
var bAnimate = true;
var bExportFrameImages = false;
var bRecordingSinglePNG = false;
 
//-------------------------------------------------------
function setup() {
  createCanvas(792, 612); // 11x8.5" at 72DPI
  frameRate(20);
  smooth();
} 
 
 
//-------------------------------------------------------
function draw() {
  background(240); 
 
  // Do all the drawing. 
  push(); 
  translate(width/2, height/2);
  drawCutLines(); 
  drawGuides(); 
  drawAllFrames();
  pop();
 
 
  if (bExportFrameImages){
    // Note that myFrameCount is incremented elsewhere.
    var filename = "myZoetrope_" + nf(myFrameCount,2) + ".png";
    saveCanvas(filename, 'png');
    if (myFrameCount >= nFrames){
      bExportFrameImages = false;
    }
  }
 
 
  if (bRecordingSinglePNG) {
    saveCanvas('myPraxinoscope.png', 'png');
    bRecordingSinglePNG = false;
  }
}
 
 
//-------------------------------------------------------
function keyPressed() {
  switch (key) {
  case ' ': 
    // Press spacebar to pause/unpause the animation. 
    bAnimate = !bAnimate;
    break;
 
  case 'p':
    case 'P':
      // Press 'p' to export a single PNG for the Zoetrope. 
      // Note: This is for 17x11" paper! 
      // Be sure to print at 100%!
      bRecordingSinglePNG = true;
      break;
 
    case 'f':
    case 'F':
      // Press 'f' to export multiple frames 
      // (in order to make an animated .GIF)
      // such as with http://gifmaker.me/
      myFrameCount = 0;
      exportFrameCount = 0;
      bExportFrameImages = true;
      bAnimate = true;
      break;
  }
}
 
//-------------------------------------------------------
function drawCutLines() {
  fill(0); 
  textAlign(CENTER, BOTTOM); 
  text("Praxinoscope Template", 0, 0-diamCutOuter/2-6); 
 
  stroke(0); 
  strokeWeight(1.0);
 
  noFill(); 
  if (!bRecordingSinglePNG) {
    fill(255); 
  }
  ellipse(0, 0, diamCutOuter, diamCutOuter);
 
  noFill(); 
  if (!bRecordingSinglePNG) {
    fill(240); 
  }
  ellipse(0, 0, diamCutInner, diamCutInner);
 
  noFill(); 
  ellipse(diamCutOuter/2 - holeDx, 0-holeDy, holeD, holeD); 
 
  line (diamCutInner/2, 0, diamCutOuter/2, 0);
}
 
//-------------------------------------------------------
function drawGuides() {
  // This function draws the guidelines. 
  // Don't draw these when we're exporting the PNG. 
  if (!bRecordingSinglePNG) {
 
    noFill(); 
    stroke(128); 
    strokeWeight(0.2); 
    ellipse(0, 0, diamArtInner, diamArtInner); 
    ellipse(0, 0, diamArtOuter, diamArtOuter);
 
    for (var i=0; i<nFrames; i++) {
      var angle = map(i, 0, nFrames, 0, TWO_PI); 
      var pxi = diamArtInner/2 * cos(angle);
      var pyi = diamArtInner/2 * sin(angle);
      var pxo = diamArtOuter/2 * cos(angle);
      var pyo = diamArtOuter/2 * sin(angle);
      stroke(128); 
      strokeWeight(0.2);
      line (pxi, pyi, pxo, pyo);
    }
 
    // Draw the red wedge outline, highlighting the main view.
    var redWedge = 7; // assuming nFrames = 10
    for (var i=redWedge; i<=(redWedge+1); i++) {
      var angle = map(i, 0, nFrames, 0, TWO_PI); 
      var pxi = diamArtInner/2 * cos(angle);
      var pyi = diamArtInner/2 * sin(angle);
      var pxo = diamArtOuter/2 * cos(angle);
      var pyo = diamArtOuter/2 * sin(angle);
      stroke(255, 0, 0); 
      strokeWeight(2.0);
      line (pxi, pyi, pxo, pyo);
    }
    noFill(); 
    stroke(255, 0, 0); 
    strokeWeight(2.0);
    var startAngle = redWedge*TWO_PI/nFrames;
    var endAngle = (redWedge+1)*TWO_PI/nFrames;
    arc(0, 0, diamArtInner, diamArtInner, startAngle, endAngle); 
    arc(0, 0, diamArtOuter, diamArtOuter, startAngle, endAngle); 
 
 
    for (var i=0; i<nFrames; i++) {
      var angle = map(i, 0, nFrames, 0, TWO_PI); 
 
      push();
      rotate(angle); 
      var originY = ((diamArtOuter + diamArtInner)/2)/2;
      translate(0, 0-originY); 
 
      noFill(); 
      stroke(128); 
      strokeWeight(0.2);
      line (-inch/2, 0, inch/2, 0); 
      line (0, -inch/2, 0, inch/2); 
 
      pop();
    }
  }
}
 
//-------------------------------------------------------
function drawAllFrames() {
  for (var i=0; i<nFrames; i++) {
    var angle = map(i, 0, nFrames, 0, TWO_PI); 
    var originY = ((diamArtOuter + diamArtInner)/2)/2;
 
    push();
    rotate(angle); 
    translate(0, 0-originY); 
    scale(0.8, 0.8); // feel free to ditch this 
 
    var whichFrame = i; 
    if (bAnimate) {
      whichFrame = (i+myFrameCount)%nFrames;
    }
    drawArtFrame (whichFrame); 
    // drawArtFrameAlternate (whichFrame); 
 
    pop();
  }
  myFrameCount++;
}
 
 
//-------------------------------------------------------
function drawArtFrame ( whichFrame ) { 
  // Draw the artwork for a generic frame of the Praxinoscope, 
  // given the framenumber (whichFrame) out of nFrames.
  // NOTE #1: The "origin" for the frame is in the center of the wedge.
  // NOTE #2: Remember that everything will appear upside-down!
 
   var nCircles = 10 
   for (var i=0; i <= nCircles; i++) {
     var radius = 20 
     if (whichFrame != i){
       fill(255);}
 
     else {
       fill(0);}
 
     var cx = radius * cos((TWO_PI/10) * i); 
     var cy = radius * sin((TWO_PI/10) * i);
     ellipse(cx, cy, 20, 20);
   }
 
}
 
//-------------------------------------------------------
function drawArtFrameAlternate( whichFrame ) { 
  // An alternate drawing test. 
  // Draw a falling object. 
 
 
  // Draw a little splat on the frame when it hits the ground. 
  if (whichFrame == (nFrames-1)) {
    stroke(0, 0, 0); 
    strokeWeight(0.5); 
    var nL = 10;
    for (var i=0; i<nL; i++) {
      var a = HALF_PI + map(i, 0, nL-1, 0, TWO_PI);
      var cx = 12 * cos(a);
      var cy = 10 * sin(a); 
      var dx = 16 * cos(a);
      var dy = 13 * sin(a); 
      line (cx, 45+cy, dx, 45+dy);
    }
  }
 
  // Draw a little box frame
  fill(255); 
  stroke(0, 0, 0);
  strokeWeight(1); 
  rect(-5, -50, 10, 100); 
 
  // Make the puck accelerate downward
  var t = map(whichFrame, 0, nFrames-1, 0, 1); 
  var t2 = pow(t, 2.0); 
  var rh = 8 + whichFrame * 0.5; // wee stretch
  var ry = map(t2, 0, 1, 0, 100-rh) - 50; 
 
  noStroke(); 
  fill(0, 0, 0);
  rect(-5, ry, 10, rh);
}