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HTML5??

HTML5???????????????????????????????????????????????????????????????????????????????????

H5?????

H5?????????????????????????????????????Canvas??????????????????????????????????

H5?H4???

?H4???HTML5?????API??????????????????????<canvas>?<audio>?<video>???????????????????

?????

??????HTML5?????????????????????????????????<header>??????????<footer>?????????????????????????????

canvas-????

<canvas>???HTML5??????????????JavaScript?????????????????????????????????????????????????

canvas-????

?<canvas>??????????<canvas>?getContext('2d')????????????fillRect(x, y, width, height)??????????????

const canvas = document.getElementById('myCanvas');
const ctx = canvas.getContext('2d');
ctx.fillStyle = 'red';
ctx.fillRect(10, 10, 100, 100);

canvas-????

???<canvas>?????????????????????????beginPath()?????moveTo()?????lineTo()?????arc()???????????????????

canvas-save&restore

?<canvas>??????save()????????????????restore()??????????????????????

canvas-??

???????????????????????????????arc()?????????????fillText()?????

canvas-??

<canvas>????????????????????????arc()?ellipse()?parabola()???????????????

canvas-??

<canvas>???????????????????????translate()???rotate()???scale()??????????????????

canvas-????

???????????????

ctx.save();
ctx.translate(100, 100);
ctx.rotate(45);
ctx.fillStyle = 'blue';
ctx.fillRect(0, 0, 100, 100);
ctx.restore();

??????

<canvas>???????????????????scale()?????????translate()???????????????

canvas??-??

???????????????

canvas??-??

??????????<canvas>??????drawClock()???????????

??

<canvas>?HTML5??????????????????????????????<canvas>?????????????????????

canvas-????

?<canvas>??????????drawImage()??????????

const img = new Image();
img.src = 'https://via.placeholder.com/150';
ctx.drawImage(img, 10, 10, 100, 100);

canvas-??

??????????????????????????????

canvas-????

<canvas>?????????????fillText()????????????

ctx.fillStyle = 'black';
ctx.font = '20px Arial';
ctx.fillText('??', 50, 50);

canvas-????

<canvas>??????????putImageData()????????????<canvas>??

canvas-?????

??getPixel()?setPixel()???????????????????????????????????????????????API?

canvas-?????

?????????????????????????

const img = new Image();
img.src = 'https://via.placeholder.com/150';
const canvas = document.getElementById('mosaicCanvas');
const ctx = canvas.getContext('2d');
img.onload = function() {
  const mosaicSize = 20;
  for(let i = 0; i < 10; i++) {
    for(let j = 0; j < 10; j++) {
      const x = i * mosaicSize;
      const y = j * mosaicSize;
      ctx.drawImage(img, x, y, mosaicSize, mosaicSize);
    }
  }
};

????

????????????<canvas>???????????

canvas-??

<canvas>????????????drawImage()??????????????<canvas>??

canvas-???

??canvas????mousemove???<canvas>?????????????????

canvas-?????

?????????????????????????????????

others

<canvas>????????????????????????????????

??

<canvas>?HTML5??????????????????????????????<canvas>?????????????????????

?????

??????HTML5???????????????????????????????

?????????

??????????????????????????????????????

??????attribute

??????attribute??controls?autoplay?loop?????????????

??????property

??????property??volume?muted?playbackRate???????????????

????????

?????????????????play()?pause()?volume()??????????????

????

???????????????????????

???????

????????????????????????????????????

??

<canvas>????<canvas>??????????

???????

????????????????????????????????????

???????

??????????????????????????

??

<canvas>?????????????????????<canvas>?????????????????????

????

????????????????????????

???

?????????????????????????????????????????????

???canvas???

??<canvas>????????????????????????

HTML5??????

HTML5????????????<header>?<footer>?<section>????????????

HTML5??????

HTML5????????????????<progress>?<meter>?????????????

HTML5??????

HTML5???????????????required?????????

HTML5????

??<canvas>?HTML5????????????????????

??

HTML5????????????????????????HTML5??????????????????????

canvas-??

??<canvas>????????????????????????

canvas-??

????????????????<canvas>???????????????????????

canvas-??

??<canvas>?????????????<canvas>??????????????????

canvas-????

?<canvas>??????????fillText()????????????????

canvas-????

??<canvas>?????API????????????????????????

canvas-?????

??<canvas>?????API???????????????????????

canvas-?????

????????????????????????????????????????????

????

????????????<canvas>???????????

canvas-??

??<canvas>?drawImage()???????????????<canvas>???????????

canvas-???

??<canvas>????mousemove???<canvas>?????????????????

canvas-?????

?????????????????????????????????

others

<canvas>????????????????????????????????

??

<canvas>?HTML5??????????????????????????????<canvas>?????????????????????

??

??<canvas>????mousedown?mousemove?mouseup??????????

???????

????????????????????????????????????

???????

??????????????????????????

??

<canvas>?????????????????????<canvas>?????????????????????

????

????????????????????????

???

?????????????????????????????????????????????

???canvas???

??<canvas>????????????????????????

HTML5??????

HTML5????????????<header>?<footer>?<section>????????????

HTML5??????

HTML5????????????????<progress>?<meter>?????????????

HTML5??????

HTML5???????????????required?????????

HTML5????

??<canvas>?HTML5????????????????????

??

HTML5????????????????????????HTML5??????????????????????

canvas-??

??<canvas>????????????????????????

canvas-??

????????????????<canvas>???????????????????????

canvas-??

??<canvas>?????????????<canvas>??????????????????

canvas-????

?<canvas>??????????fillText()????????????????

canvas-????

??<canvas>?????API????????????????????????

canvas-?????

??<canvas>?????API???????????????????????

canvas-?????

????????????????????????????????????????????

????

????????????<canvas>???????????

canvas-??

??<canvas>?drawImage()???????????????<canvas>???????????

canvas-???

??<canvas>????mousemove???<canvas>?????????????????

canvas-?????

?????????????????????????????????

others

<canvas>????????????????????????????????

??

<canvas>?HTML5??????????????????????????????<canvas>?????????????????????