以下のコードを使用して、キャンバスにロードされた画像に領域を描画し、描画された領域を色で塗りつぶすことができます。
次に、描画した領域を色ではなく画像で塗りつぶす必要があります。何かのようなもの:
canvas.fillStyle ='url(myimage.jpg)';
それ以外の
canvas.fillStyle ='#123456'//塗りつぶしの色の例
HTML:
<body>
<div id="main" class="container">
<h1>Image Maps Canvas Drawing</h1>
<form>
<div class="row">
<div class="span6">
<textarea rows=3 name="coords1" class="canvas-area input-xxlarge" disabled
placeholder="Shape Coordinates"
data-image-url="img1.jpg"></textarea>
</div>
<div class="span6">
</div>
</form>
</div>
<script language="javascript" src="//ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<script language="javascript" src="jquery.canvasAreaDraw.min.js"></script>
</body>
jquery.canvasAreaDraw.min.js
(function (e) {
e.fn.canvasAreaDraw = function (e) {
this.each(function (n, r) {
t.apply(r, [n, r, e])
})
};
var t = function (t, r, i) {
var s, o, u, a, f, l, c, h, p, d, v, m, g, y, b; u = e.extend({
imageUrl: e(this).attr("data-image-url")
}, i), e(this).val().length ? s = e(this).val().split(",").map(function (e) {
return parseInt(e, 10)
}) : s = [], a = e('<button type="button" class="btn"><i class="icon-trash"></i>Clear</button>'),
f = e("<canvas id='your_canvas'>"), l = f[0].getContext("2d"), c = new Image, m = function () {
f.attr("height", c.height).attr("width", c.width), h()
}, e(c).load(m), c.src = u.imageUrl, c.loaded && m(), f.css(
{ background: "url(" + c.src + ")" }), e(document).ready(function () {
e(r).after("<br>", f, "<br>", a), a.click(g), f.bind("mousedown", p), f.bind("contextmenu", y), f.bind("mouseup", d)
}), g = function () {
s = [], h()
}, v = function (t) {
t.offsetX || (t.offsetX = t.pageX - e(t.target).offset().left, t.offsetY = t.pageY - e(t.target).offset().top), s[o] = Math.round(t.offsetX), s[o + 1] = Math.round(t.offsetY), h()
},
d = function () {
e(this).unbind("mousemove"), b(), o = null
}, y = function (t) {
t.preventDefault(), t.offsetX || (t.offsetX = t.pageX - e(t.target).offset().left, t.offsetY = t.pageY - e(t.target).offset().top);
var n = t.offsetX, r = t.offsetY;
for (var i = 0; i < s.length; i += 2) {
dis = Math.sqrt(Math.pow(n - s[i], 2) + Math.pow(r - s[i + 1], 2));
if (dis < 6)
return s.splice(i, 2), h(), b(), !1
}
return !1
}, p = function (t) {
var r, i, u, a, f = s.length;
if (t.which === 3)
return !1;
t.preventDefault(), t.offsetX || (t.offsetX = t.pageX - e(t.target).offset().left, t.offsetY = t.pageY - e(t.target).offset().top), r = t.offsetX, i = t.offsetY;
for (var l = 0; l < s.length; l += 2) {
u = Math.sqrt(Math.pow(r - s[l], 2) + Math.pow(i - s[l + 1], 2));
if (u < 6) return o = l, e(this).bind("mousemove", v), !1
}
for (var l = 0; l < s.length; l += 2)
l > 1 && (a = n(r, i, s[l], s[l + 1], s[l - 2], s[l - 1], !0), a < 6 && (f = l));
return console.log(s), s.splice(f, 0, Math.round(r), Math.round(i)), o = f, e(this).bind("mousemove", v), h(), b(), !1
}, h = function () {
l.canvas.width = l.canvas.width;
if (s.length < 2)
return !1;
l.globalCompositeOperation = "destination-over", l.fillStyle = "rgb(255,255,255)", l.strokeStyle = "rgb(255,20,20)", l.lineWidth = 1, l.beginPath(),
l.moveTo(s[0], s[1]);
for (var e = 0; e < s.length; e += 2)
l.fillRect(s[e] - 2, s[e + 1] - 2, 4, 4), l.strokeRect(s[e] - 2, s[e + 1] - 2, 4, 4), s.length > 2 && e > 1 && l.lineTo(s[e], s[e + 1]); l.closePath(), l.fillStyle = "rgba(255,0,0,0.3)", l.fill(), l.stroke(), b()
}, b = function () {
e(r).val(s.join(","))
}
}; e(document).ready(function () {
e(".canvas-area[data-image-url]").canvasAreaDraw()
});
var n = function (e, t, n, r, i, s, o) {
function u(e, t, n, r) {
return Math.sqrt((e -= n) * e + (t -= r) * t)
}
if (o && !(o = function (e, t, n, r, i, s) {
if (!(i - n)) return { x: n, y: t };
if (!(s - r))
return { x: e, y: r };
var o, u = -1 / ((s - r) / (i - n));
return {
x: o = (i * (e * u - t + r) + n * (e * -u + t - s)) / (u * (i - n) + r - s), y: u * o - u * e + t
}
}
(e, t, n, r, i, s), o.x >= Math.min(n, i) && o.x <= Math.max(n, i) && o.y >= Math.min(r, s) && o.y <= Math.max(r, s))) {
var a = u(e, t, n, r), f = u(e, t, i, s);
return a > f ? f : a
}
var l = r - s, c = i - n, h = n * s - r * i;
return Math.abs(l*e+c*t+h)/Math.sqrt(l*l+c*c)}})(jQuery);