Как изменить размер до меньшего круга

Question

Как изменить размер круга на меньший? Я копирую этот источник, но не нашел. Этот круговой рисунок с холстом. я пытаюсь изменить что-то, но результат не получается правильно. HTML-:

<div style='position: absolute: top: 0px; left: 0px; background-color: #FFFFFF; width: 300px; height: 2000px'> 
       <div id='mainDiv' style='position: absolute; width: 250px; height: 250px; visibility: hidden; cursor: pointer'> 
        <canvas id='g2'></canvas> 
        <canvas id='luminosity' width='250' height='250' style='position: absolute; left: 0px; top: 0px'></canvas> 
        <canvas id='hue-selector' width='15' height='15' style='position: absolute'></canvas> 
        <canvas id='luminosity-selector' width='15' height='15' style='position: absolute'></canvas> 
       </div>  
      </div> 

       <canvas id='selColor' width='15' height='15' style='position: absolute; border: 1px solid #000'></canvas> 

Javascript:

$('#selColor').click(function(e) { 
    onMenuForegroundColor(); 
}); 

function HSB2RGB(j, d, c) { 
    var e, g, l, h, k, b, a, m; 
    if (c == 0) { 
     return [0, 0, 0] 
    } 
    j *= 0.016666667; 
    d *= 0.01; 
    c *= 0.01; 
    h = Math.floor(j); 
    k = j - h; 
    b = c * (1 - d); 
    a = c * (1 - (d * k)); 
    m = c * (1 - (d * (1 - k))); 
    switch (h) { 
     case 0: 
      e = c; 
      g = m; 
      l = b; 
      break; 
     case 1: 
      e = a; 
      g = c; 
      l = b; 
      break; 
     case 2: 
      e = b; 
      g = c; 
      l = m; 
      break; 
     case 3: 
      e = b; 
      g = a; 
      l = c; 
      break; 
     case 4: 
      e = m; 
      g = b; 
      l = c; 
      break; 
     case 5: 
      e = c; 
      g = b; 
      l = a; 
      break 
    } 
    return [e, g, l] 
} 

function RGB2HSB(c, d, k) { 
    var j, h, e, g, b, a; 
    j = Math.min(Math.min(c, d), k); 
    a = Math.max(Math.max(c, d), k); 
    if (j == a) { 
     return [0, 0, a * 100] 
    } 
    h = (c == j) ? d - k : ((d == j) ? k - c : c - d); 
    e = (c == j) ? 3 : ((d == j) ? 5 : 1); 
    g = Math.floor((e - h/(a - j)) * 60) % 360; 
    b = Math.floor(((a - j)/a) * 100); 
    a = Math.floor(a * 100); 
    return [g, b, a] 
} 

function ColorSelector(a) { 
    this.init(a) 
} 

ColorSelector.prototype = { 
    container: null, 
    color: [0, 0, 0], 
    hueSelector: null, 
    luminosity: null, 
    luminosityData: null, 
    luminositySelector: null, 
    luminosityPosition: null, 
    dispatcher: null, 
    changeEvent: null, 

    init: function(k) { 
     var m = this, 
      b1, g2, d3; 

     this.container = document.getElementById('mainDiv') 
     this.container.addEventListener("mousedown", l, false); 
     this.container.addEventListener("touchstart", f, false); 


     g2 = document.getElementById('g2'); 
     g2.width = k.width; 
     g2.height = k.height; 

     b1 = g2.getContext("2d"); 
     b1.drawImage(k, 0, 0, g2.width, g2.height); 
     d3 = b1.getImageData(0, 0, g2.width, g2.height).data; 


     this.luminosity = document.getElementById('luminosity'); 
     this.hueSelector = document.getElementById('hue-selector'); 
     this.hueSelector.style.left = ((g2.width - 15)/2) + "px"; 
     this.hueSelector.style.top = ((g2.height - 15)/2) + "px"; 


     b1 = this.hueSelector.getContext("2d"); 
     b1.lineWidth = 2; 
     b1.strokeStyle = "rgba(0, 0, 0, 0.5)"; 
     b1.beginPath(); 
     b1.arc(8, 8, 6, 0, Math.PI * 2, true); 
     b1.stroke(); 
     b1.strokeStyle = "rgba(256, 256, 256, 0.8)"; 
     b1.beginPath(); 
     b1.arc(7, 7, 6, 0, Math.PI * 2, true); 
     b1.stroke(); 

     this.luminosityPosition = [(k.width - 15), (k.height - 15)/2]; 


     this.luminositySelector = document.getElementById('luminosity-selector'); 
     this.luminositySelector.style.left = (this.luminosityPosition[0] - 7) + "px"; 
     this.luminositySelector.style.top = (this.luminosityPosition[1] - 7) + "px"; 
     b1 = this.luminositySelector.getContext("2d"); 
     b1.drawImage(this.hueSelector, 0, 0, this.luminositySelector.width, this.luminositySelector.height); 

     this.dispatcher = document.createElement("div"); 
     this.changeEvent = document.createEvent("Events"); 
     this.changeEvent.initEvent("change", true, true); 

     function l(n) { 
      window.addEventListener("mousemove", c, false); 
      window.addEventListener("mouseup", h, false); 
      e(n.clientX - m.container.offsetLeft, n.clientY - m.container.offsetTop) 
     } 

     function c(n) { 
      e(n.clientX - m.container.offsetLeft, n.clientY - m.container.offsetTop) 
     } 

     function h(n) { 
      window.removeEventListener("mousemove", c, false); 
      window.removeEventListener("mouseup", h, false); 
      e(n.clientX - m.container.offsetLeft, n.clientY - m.container.offsetTop) 
     } 

     function f(n) { 
      if (n.touches.length == 1) { 
       n.preventDefault(); 
       window.addEventListener("touchmove", a, false); 
       window.addEventListener("touchend", j, false); 
       e(n.touches[0].pageX - m.container.offsetLeft, n.touches[0].pageY - m.container.offsetTop) 
      } 
     } 

     function a(n) { 
      if (n.touches.length == 1) { 
       n.preventDefault(); 
       e(n.touches[0].pageX - m.container.offsetLeft, n.touches[0].pageY - m.container.offsetTop) 
      } 
     } 

     function j(n) { 
      if (n.touches.length == 0) { 
       n.preventDefault(); 
       window.removeEventListener("touchmove", a, false); 
       window.removeEventListener("touchend", j, false) 
      } 
     } 

     function e(o, t) { 
      var q, p, r, n, s; 
      q = o - 125; 
      p = t - 125; 
      r = Math.sqrt(q * q + p * p); 
      if (r < 90) { 
       m.hueSelector.style.left = (o - 7) + "px"; 
       m.hueSelector.style.top = (t - 7) + "px"; 
       m.updateLuminosity([d3[(o + (t * 250)) * 4], d3[(o + (t * 250)) * 4 + 1], d3[(o + (t * 250)) * 4 + 2]]) 
      } else { 
       if (r > 100) { 
        n = q/r; 
        s = p/r; 
        m.luminosityPosition[0] = (n * 110) + 125; 
        m.luminosityPosition[1] = (s * 110) + 125; 
        m.luminositySelector.style.left = (m.luminosityPosition[0] - 7) + "px"; 
        m.luminositySelector.style.top = (m.luminosityPosition[1] - 7) + "px" 
       } 
      } 
      o = Math.floor(m.luminosityPosition[0]); 
      t = Math.floor(m.luminosityPosition[1]); 
      m.color[0] = m.luminosityData[(o + (t * 250)) * 4]; 
      m.color[1] = m.luminosityData[(o + (t * 250)) * 4 + 1]; 
      m.color[2] = m.luminosityData[(o + (t * 250)) * 4 + 2]; 
      m.dispatchEvent(m.changeEvent) 
     } 
    }, 
    show: function() { 
     this.container.style.visibility = "visible" 
    }, 
    hide: function() { 
     this.container.style.visibility = "hidden" 
    }, 
    getColor: function() { 
     return this.color 
    }, 
    setColor: function(c) { 
     var a, e, f, d, b = Math.PI/180; 
     this.color = c; 
     a = RGB2HSB(c[0]/255, c[1]/255, c[2]/255); 
     e = a[0] * b; 
     f = (a[1]/100) * 90; 
     this.hueSelector.style.left = ((Math.cos(e) * f + 125) - 7) + "px"; 
     this.hueSelector.style.top = ((Math.sin(e) * f + 125) - 7) + "px"; 
     d = HSB2RGB(a[0], a[1], 100); 
     d[0] *= 255; 
     d[1] *= 255; 
     d[2] *= 255; 
     this.updateLuminosity(d); 
     e = (a[2]/100) * 360 * b; 
     this.luminosityPosition[0] = (Math.cos(e) * 110) + 125; 
     this.luminosityPosition[1] = (Math.sin(e) * 110) + 125; 
     this.luminositySelector.style.left = (this.luminosityPosition[0] - 7) + "px"; 
     this.luminositySelector.style.top = (this.luminosityPosition[1] - 7) + "px"; 
     this.dispatchEvent(this.changeEvent) 
    }, 
    updateLuminosity: function(j) { 
     var d, f, l, g, p, b, a, o = 100, 
      h = 120, 
      k, n = 1080/2, 
      e = 1/n, 
      c = Math.PI/180, 
      m = (n/360); 
     b = this.luminosity.width/2; 
     a = this.luminosity.height/2; 
     d = this.luminosity.getContext("2d"); 
     d.lineWidth = 3; 
     d.clearRect(0, 0, this.luminosity.width, this.luminosity.height); 
     for (k = 0; k < n; k++) { 
      f = k/m * c; 
      l = Math.cos(f); 
      g = Math.sin(f); 
      p = 255 - (k * e) * 255; 
      d.strokeStyle = "rgb(" + Math.floor(j[0] - p) + "," + Math.floor(j[1] - p) + "," + Math.floor(j[2] - p) + ")"; 
      d.beginPath(); 
      d.moveTo(l * o + b, g * o + a); 
      d.lineTo(l * h + b, g * h + a); 
      d.stroke() 
     } 
     this.luminosityData = d.getImageData(0, 0, this.luminosity.width, this.luminosity.height).data 
    }, 
    addEventListener: function(b, c, a) { 
     this.dispatcher.addEventListener(b, c, a) 
    }, 
    dispatchEvent: function(a) { 
     this.dispatcher.dispatchEvent(a) 
    }, 
    removeEventListener: function(b, c, a) { 
     this.dispatcher.removeEventListener(b, c, a) 
    } 
}; 

function Palette() { 
    var e, d, b, a, n = 90, 
     m = 1080, 
     f = 1/m, 
     l = m/360, 
     c = Math.PI/180, 
     j, h, k, g, o; 
    e = document.createElement("canvas"); 
    e.width = 250; 
    e.height = 250; 
    b = e.width/2; 
    a = e.height/2; 
    d = e.getContext("2d"); 
    d.lineWidth = 1; 
    for (j = 0; j < m; j++) { 
     h = j/l * c; 
     k = Math.cos(h); 
     g = Math.sin(h); 
     d.strokeStyle = "hsl(" + Math.floor((j * f) * 360) + ", 100%, 50%)"; 
     d.beginPath(); 
     d.moveTo(k + b, g + a); 
     d.lineTo(k * n + b, g * n + a); 
     d.stroke() 
    } 
    o = d.createRadialGradient(b, b, 0, b, b, n); 
    o.addColorStop(0, "rgba(255, 255, 255, 1)"); 
    o.addColorStop(1, "rgba(255, 255, 255, 0)"); 
    d.fillStyle = o; 
    d.fillRect(0, 0, e.width, e.height); 
    return e 
} 

var SCREEN_WIDTH = window.innerWidth, 
    SCREEN_HEIGHT = window.innerHeight, 
    COLOR = [0, 0, 0], 
    i, 
    container, foregroundColorSelector, canvas, flattenCanvas, context, isFgColorSelectorVisible = false; 
init(); 

function init() { 
    var hash, palette; 
    container = document.createElement("div"); 

    document.body.appendChild(container); 
    canvas = document.createElement("canvas"); 
    canvas.width = SCREEN_WIDTH; 
    canvas.height = SCREEN_HEIGHT; 
    canvas.style.cursor = "crosshair"; 
    container.appendChild(canvas); 
    context = canvas.getContext("2d"); 
    palette = new Palette(); 
    foregroundColorSelector = new ColorSelector(palette); 
    foregroundColorSelector.addEventListener("change", onForegroundColorSelectorChange, false); 
    container.appendChild(foregroundColorSelector.container); 
    onMenuForegroundColor(); 

    setColorAll(COLOR); 

    foregroundColorSelector.setColor(COLOR); 
    canvas.addEventListener("mousedown", onCanvasMouseDown, false); 
} 

function onForegroundColorSelectorChange(a) { 
    COLOR = foregroundColorSelector.getColor(); 
    setColorAll(COLOR); 
} 

//show palette 
function onMenuForegroundColor() { 

    hidePalette(); 
    foregroundColorSelector.show(); 
    foregroundColorSelector.container.style.left = 0; 
    foregroundColorSelector.container.style.top = 0; 
    isFgColorSelectorVisible = true 
} 

function hidePalette() { 
    foregroundColorSelector.hide();  
} 


/* mouse and touches up down move */ 
//mouse down canvas 
function onCanvasMouseDown(b) { 
    hidePalette(); 
    window.addEventListener("mouseup", onCanvasMouseUp, false) 
} 

//up on canvas 
function onCanvasMouseUp() { 
    window.removeEventListener("mouseup", onCanvasMouseUp, false); 
} 

function setColorAll(color) { 
    foregroundColor = document.getElementById('selColor'); 
    var foregroundCtx = this.foregroundColor.getContext("2d"); 
    foregroundCtx.fillStyle = "rgb(" + COLOR[0] + "," + COLOR[1] + "," + COLOR[2] + ")"; 
    foregroundCtx.fillRect(0, 0, foregroundColor.width, foregroundColor.height); 
} 

Пожалуйста, проверьте скрипку Here

Answer 1

Добавьте следующий CSS

#mainDiv { 
    transform: scale(.7); //scale down to 70% of the current height 
} 

Answer 2

Пока я не собираюсь рассмотреть ваши 300+ линия скрипки (см.https://stackoverflow.com/help/mcve), если вы хотите масштабировать содержимое холста, вы можете:

1. Очистить холст,
2. context.scale(scalefactorX,scalefactorY) масштабировать все рисунки, которые следуют,
3. перерисовать все содержимое холста.
4. Всегда очистить от водяного камня холста: context.scale(-scalefactorX,-scalefactorY)