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Adding Classes

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div id="container">
  <div id="frame">
    <canvas id="mondrian" width="600" height="375"></canvas>
  </div>
  
  <footer>Inspired by Mondrian and <a href="http://s2.b3ta.com/host/creative/46786/1458208285/pongdrian.gif" target="_blank">this</a>. By  Bas Groothedde.</footer>
</div>
!

CSS 

              
                @import url(https://fonts.googleapis.com/css?family=Roboto:300,100,500);

body {
  margin: 0;
  background: #d9d9d9;
  
  &, & a {
    color: #656565;
    font-weight: 500;
  }
  
  a {
    &:hover {
      color: #000;
    }
  }
}

#container {
  transform: translate(-50%, -50%);
  position: absolute;
  left: 50%; top: 50%;
  width: 600;
  height: 375;

  footer {
    text-align: center;
    font-family: Roboto, tahoma, verdana, sans-serif;
    font-weight: 300;
    font-size: 12pt;
    padding-top: 2em;
  }
  
  #frame {
    border: #121212 15px solid;
    box-shadow: inset 0px 0px 45px 0px black,
                0px 0px 45px 0px black;
  }

  canvas {
    border: #ffffff 20px solid;
    display: block;
  }
}
!

JS 

              
                function ClearRect() {}

ClearRect.prototype.step = function(width, height) {};
ClearRect.prototype.draw = function(context) {
  context.fillStyle = '#ffffff';
  context.strokeStyle = '#000000';
  context.lineWidth = 5;
  context.beginPath();
  context.rect(0, 0, context.canvas.width, context.canvas.height);
  context.fill();
  context.stroke();
  context.closePath();
};

function Rectangle(x, y, w, h, colour) {
  this.x = x;
  this.y = y;
  this.w = w;
  this.h = h;
  this.c = colour;
}

Rectangle.prototype.step = function(width, height) {};
Rectangle.prototype.draw = function(context) {
  context.fillStyle = this.c;
  context.fillRect(this.x, this.y, this.w, this.h);
};

function Line(x1, y1, x2, y2) {
  this.x1 = x1;
  this.y1 = y1;
  this.x2 = x2;
  this.y2 = y2;
}

Line.prototype.step = function(width, height) {};
Line.prototype.draw = function(context) {
  context.lineWidth = 5;
  context.strokeStyle = '#000000';
  context.beginPath();
  context.moveTo(this.x1, this.y1);
  context.lineTo(this.x2, this.y2);
  context.stroke();
  context.closePath();
};

function Dot(x, y, vx, vy) {
  this.x  = x;
  this.y  = y;
  this.vx = vx;
  this.vy = vy;
  this.w  = 26;
  this.h  = 26;
  
  this.prediction = {
    left: {x: 0, y: 0},
    right: {x: 0, y: 0},
    heading: -1
  }
}

Dot.prototype.step = function(width, height) {
  this.x += this.vx;
  this.y += this.vy;
  
  if(this.x <= 80) {
    this.x = 80;
    this.vx *= -1;
  }
  
  if(this.x >= 525 - this.w) {
    this.x = (525 - this.w);
    this.vx *= -1;
  }
  
  if(this.y <= 17) {
    this.y = 17;
    this.vy *= -1;
  }

  if(this.y >= 351 - this.h) {
    this.y = (351 - this.h);
    this.vy *= -1;
  }
  
  var x = this.x,
      y = this.y,
      vx = this.vx,
      vy = this.vy;
  
  // dirty prediction of the target area 
  if(this.vx < 0) {
    while(x > 80) {
      x += vx;
      y += vy;
      
      if(y <= 17) y = 17, vy *= -1;
      if(y >= 351 - this.h) y = 351 - this.h, vy *= -1;
    }

    this.prediction.heading = -1;
    this.prediction.left.x = x;
    this.prediction.left.y = y;
  } else {
    while(x < 525) {
      x += vx;
      y += vy;
      
      if(y <= 17) y = 17, vy *= -1;
      if(y >= 351 - this.h) y = 351 - this.h, vy *= -1;
    }
    
    this.prediction.heading = 1;
    this.prediction.right.x = x;
    this.prediction.right.y = y;
  }
};

Dot.prototype.draw = function(context) {
  context.fillStyle = '#000000';
  context.fillRect(this.x, this.y, this.w, this.h);
};

function SimulatedPlayer(side, dot) {
  this.side = side;
  this.dot  = dot;
  
  if(this.side === -1) {
    this.prediction = 'left';
    this.x = 37.5;
    this.y = 177.5;
  } else {
    this.prediction = 'right';
    this.x = 525.5;
    this.y = 177.5;
  }
}

SimulatedPlayer.prototype.step = function(width, height) {
  // animate towards this.dot.prediction if the heading is this.side
  if(this.dot.prediction.heading === this.side) {
    var boundary = (this.side === -1 ? 80 : 525),
        maximum  = 525 - 80,
        distance = (this.side === -1 ? this.dot.x - boundary :  boundary - this.dot.x),
        factor   = 1 - (distance / maximum);
    
    if(factor > .15) {
      var ty = (this.dot.prediction[this.prediction].y - 45 + (this.dot.h / 2));
      this.y = (this.y + (ty - this.y) * factor);
    }

    if(this.y <= 17) this.y = 17;
    if(this.y >= 351 - 90) this.y = 351 - 90;
  }
};

SimulatedPlayer.prototype.draw = function(context) {
  context.fillStyle   = '#0000ff';
  context.lineWidth   = 5;
  context.strokeStyle = '#000000';
  context.beginPath();
  context.rect(this.x, this.y, (this.side === -1 ? 42 : 40), 90);
  context.fill();
  context.stroke();
  context.closePath();
};

function StaticLayer(width, height) {
  this.canvas        = document.createElement('canvas');
  this.context       = this.canvas.getContext('2d');
  this.renderables   = [];
  this.canvas.width  = width;
  this.canvas.height = height;
}

StaticLayer.prototype.push = function(renderable) {
  this.renderables.push(renderable);
};

StaticLayer.prototype.prepare = function() {
  this.context.clearRect(0, 0, this.canvas.width, this.canvas.height);
  
  for(var i in this.renderables) this.renderables[i].draw(this.context);
};

StaticLayer.prototype.step = function(width, height) {};
StaticLayer.prototype.draw = function(context) {
  context.drawImage(this.canvas, 0, 0);
};

window.addEventListener('load', function() {
  var canvas = document.getElementById('mondrian'),
      context = canvas.getContext('2d'),
      renderables = [],
      staticRenderables = new StaticLayer(canvas.width, canvas.height);
  
  // Static renderables are rendered to a canvas once, and the resulting image
  // is used. This is faster than rendering them all each frame. 
  
  // Clear overlay
  staticRenderables.push(new ClearRect());
  
  // Squares
  staticRenderables.push(new Rectangle(2.0,   64,    37.5, 157, "#ff0000")); // 1st one, red
  staticRenderables.push(new Rectangle(2.0,   351,   37.5, 22,  "#0000ff")); // 2nd one, blue
  staticRenderables.push(new Rectangle(80.5,  17.5,  125,  120, "#ff0000")); // 3rd one, red
  staticRenderables.push(new Rectangle(205.5, 2.0,   23,   16,  "#ff0000")); // 4th one, red
  staticRenderables.push(new Rectangle(205.5, 351,   23,   22,  "#ffe700")); // 5th one, yellow
  staticRenderables.push(new Rectangle(228.5, 351,   155,  22,  "#ff0000")); // 6th one, red
  staticRenderables.push(new Rectangle(333.5, 2.0,   54,   165, "#ffe700")); // 7th one, yellow
  staticRenderables.push(new Rectangle(387.5, 2.0,   136,  16,  "#0000ff")); // 8th one, blue
  staticRenderables.push(new Rectangle(387.5, 277.5, 136,  74,  "#ffe700")); // 9th one, yellow
  staticRenderables.push(new Rectangle(566.5, 17.5,  31.5, 47,  "#ff0000")); // 10th one, red
  staticRenderables.push(new Rectangle(566.5, 221.5, 31.5, 129, "#ffe700")); // 11th one, yellow
  
  // Lines 
  staticRenderables.push(new Line(37.5,  0, 37.5,  canvas.height)); // 1st vertical line, left of player
  staticRenderables.push(new Line(80.0,  0, 80.0,  canvas.height)); // 2nd vertical line, right of player
  staticRenderables.push(new Line(205.0, 0, 205.0, canvas.height)); // 3rd vertical line
  staticRenderables.push(new Line(230.5, 0, 230.5, canvas.height)); // 4th vertical line
  staticRenderables.push(new Line(335.0, 0, 335.0, canvas.height)); // 5th vertical line
  staticRenderables.push(new Line(385.5, 0, 385.5, canvas.height)); // 6th vertical line
  staticRenderables.push(new Line(525.0, 0, 525.0, canvas.height)); // 7th vertical line, left of player
  staticRenderables.push(new Line(566.5, 0, 566.5, canvas.height)); // 8th vertical line, right of player
  
  staticRenderables.push(new Line(0, 17.5,  canvas.width, 17.5));   // 1st horizontal line
  staticRenderables.push(new Line(0, 351.0, canvas.width, 351.0));  // 2nd horizontal line
  
  // First separate line block
  staticRenderables.push(new Line(0, 64.0,  37.5,  64.0));
  staticRenderables.push(new Line(0, 221.0, 37.5, 221.0));
  
  // Second separate line block
  staticRenderables.push(new Line(37.5, 110.5, 80.0, 110.5));       // 1st block
  
  // remaining filler lines
  staticRenderables.push(new Line(79, 135.5, 525, 135.5));
  staticRenderables.push(new Line(79, 167.5, 525, 167.5));
  
  staticRenderables.push(new Line(80.0, 200.0, 205.0, 200.0));
  staticRenderables.push(new Line(385.5, 277.5, 525.0, 277.5));
  
  staticRenderables.push(new Line(566.5, 63.0,  canvas.width, 63.0));
  staticRenderables.push(new Line(566.5, 221.0, canvas.width, 221.0));
  staticRenderables.prepare();
  
  var dot = new Dot(100, 100, 7, 3.7);
  
  // Add the static layer
  renderables.push(staticRenderables);
  
  // Add the dot and players 
  renderables.push(dot);
  renderables.push(new SimulatedPlayer(-1, dot));
  renderables.push(new SimulatedPlayer(1, dot));
  
  function animation() {
    
    // Step & render!
    for(var i in renderables) renderables[i].step(canvas.width, canvas.height);
    for(var i in renderables) renderables[i].draw(context);
    
    requestAnimationFrame(animation);
  }
  
  animation();
  
});
!
999px

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