guoren/public/javascripts/skycons.js

715 lines
18 KiB
JavaScript
Executable File

var Skycons;
(function(global) {
"use strict";
/* Set up a RequestAnimationFrame shim so we can animate efficiently FOR
* GREAT JUSTICE. */
var requestInterval, cancelInterval;
(function() {
var raf = global.requestAnimationFrame ||
global.webkitRequestAnimationFrame ||
global.mozRequestAnimationFrame ||
global.oRequestAnimationFrame ||
global.msRequestAnimationFrame ,
caf = global.cancelAnimationFrame ||
global.webkitCancelAnimationFrame ||
global.mozCancelAnimationFrame ||
global.oCancelAnimationFrame ||
global.msCancelAnimationFrame ;
if(raf && caf) {
requestInterval = function(fn, delay) {
var handle = {value: null};
function loop() {
handle.value = raf(loop);
fn();
}
loop();
return handle;
};
cancelInterval = function(handle) {
caf(handle.value);
};
}
else {
requestInterval = setInterval;
cancelInterval = clearInterval;
}
}());
/* Catmull-rom spline stuffs. */
/*
function upsample(n, spline) {
var polyline = [],
len = spline.length,
bx = spline[0],
by = spline[1],
cx = spline[2],
cy = spline[3],
dx = spline[4],
dy = spline[5],
i, j, ax, ay, px, qx, rx, sx, py, qy, ry, sy, t;
for(i = 6; i !== spline.length; i += 2) {
ax = bx;
bx = cx;
cx = dx;
dx = spline[i ];
px = -0.5 * ax + 1.5 * bx - 1.5 * cx + 0.5 * dx;
qx = ax - 2.5 * bx + 2.0 * cx - 0.5 * dx;
rx = -0.5 * ax + 0.5 * cx ;
sx = bx ;
ay = by;
by = cy;
cy = dy;
dy = spline[i + 1];
py = -0.5 * ay + 1.5 * by - 1.5 * cy + 0.5 * dy;
qy = ay - 2.5 * by + 2.0 * cy - 0.5 * dy;
ry = -0.5 * ay + 0.5 * cy ;
sy = by ;
for(j = 0; j !== n; ++j) {
t = j / n;
polyline.push(
((px * t + qx) * t + rx) * t + sx,
((py * t + qy) * t + ry) * t + sy
);
}
}
polyline.push(
px + qx + rx + sx,
py + qy + ry + sy
);
return polyline;
}
function downsample(n, polyline) {
var len = 0,
i, dx, dy;
for(i = 2; i !== polyline.length; i += 2) {
dx = polyline[i ] - polyline[i - 2];
dy = polyline[i + 1] - polyline[i - 1];
len += Math.sqrt(dx * dx + dy * dy);
}
len /= n;
var small = [],
target = len,
min = 0,
max, t;
small.push(polyline[0], polyline[1]);
for(i = 2; i !== polyline.length; i += 2) {
dx = polyline[i ] - polyline[i - 2];
dy = polyline[i + 1] - polyline[i - 1];
max = min + Math.sqrt(dx * dx + dy * dy);
if(max > target) {
t = (target - min) / (max - min);
small.push(
polyline[i - 2] + dx * t,
polyline[i - 1] + dy * t
);
target += len;
}
min = max;
}
small.push(polyline[polyline.length - 2], polyline[polyline.length - 1]);
return small;
}
*/
/* Define skycon things. */
/* FIXME: I'm *really really* sorry that this code is so gross. Really, I am.
* I'll try to clean it up eventually! Promise! */
var KEYFRAME = 500,
STROKE = 0.08,
TWO_PI = 2.0 * Math.PI,
TWO_OVER_SQRT_2 = 2.0 / Math.sqrt(2);
function circle(ctx, x, y, r) {
ctx.beginPath();
ctx.arc(x, y, r, 0, TWO_PI, false);
ctx.fill();
}
function line(ctx, ax, ay, bx, by) {
ctx.beginPath();
ctx.moveTo(ax, ay);
ctx.lineTo(bx, by);
ctx.stroke();
}
function puff(ctx, t, cx, cy, rx, ry, rmin, rmax) {
var c = Math.cos(t * TWO_PI),
s = Math.sin(t * TWO_PI);
rmax -= rmin;
circle(
ctx,
cx - s * rx,
cy + c * ry + rmax * 0.5,
rmin + (1 - c * 0.5) * rmax
);
}
function puffs(ctx, t, cx, cy, rx, ry, rmin, rmax) {
var i;
for(i = 5; i--; )
puff(ctx, t + i / 5, cx, cy, rx, ry, rmin, rmax);
}
function cloud(ctx, t, cx, cy, cw, s, color) {
t /= 30000;
var a = cw * 0.21,
b = cw * 0.12,
c = cw * 0.24,
d = cw * 0.28;
ctx.fillStyle = color;
puffs(ctx, t, cx, cy, a, b, c, d);
ctx.globalCompositeOperation = 'destination-out';
puffs(ctx, t, cx, cy, a, b, c - s, d - s);
ctx.globalCompositeOperation = 'source-over';
}
function sun(ctx, t, cx, cy, cw, s, color) {
t /= 120000;
var a = cw * 0.25 - s * 0.5,
b = cw * 0.32 + s * 0.5,
c = cw * 0.50 - s * 0.5,
i, p, cos, sin;
ctx.strokeStyle = color;
ctx.lineWidth = s;
ctx.lineCap = "round";
ctx.lineJoin = "round";
ctx.beginPath();
ctx.arc(cx, cy, a, 0, TWO_PI, false);
ctx.stroke();
for(i = 8; i--; ) {
p = (t + i / 8) * TWO_PI;
cos = Math.cos(p);
sin = Math.sin(p);
line(ctx, cx + cos * b, cy + sin * b, cx + cos * c, cy + sin * c);
}
}
function moon(ctx, t, cx, cy, cw, s, color) {
t /= 15000;
var a = cw * 0.29 - s * 0.5,
b = cw * 0.05,
c = Math.cos(t * TWO_PI),
p = c * TWO_PI / -16;
ctx.strokeStyle = color;
ctx.lineWidth = s;
ctx.lineCap = "round";
ctx.lineJoin = "round";
cx += c * b;
ctx.beginPath();
ctx.arc(cx, cy, a, p + TWO_PI / 8, p + TWO_PI * 7 / 8, false);
ctx.arc(cx + Math.cos(p) * a * TWO_OVER_SQRT_2, cy + Math.sin(p) * a * TWO_OVER_SQRT_2, a, p + TWO_PI * 5 / 8, p + TWO_PI * 3 / 8, true);
ctx.closePath();
ctx.stroke();
}
function rain(ctx, t, cx, cy, cw, s, color) {
t /= 1350;
var a = cw * 0.16,
b = TWO_PI * 11 / 12,
c = TWO_PI * 7 / 12,
i, p, x, y;
ctx.fillStyle = color;
for(i = 4; i--; ) {
p = (t + i / 4) % 1;
x = cx + ((i - 1.5) / 1.5) * (i === 1 || i === 2 ? -1 : 1) * a;
y = cy + p * p * cw;
ctx.beginPath();
ctx.moveTo(x, y - s * 1.5);
ctx.arc(x, y, s * 0.75, b, c, false);
ctx.fill();
}
}
function sleet(ctx, t, cx, cy, cw, s, color) {
t /= 750;
var a = cw * 0.1875,
b = TWO_PI * 11 / 12,
c = TWO_PI * 7 / 12,
i, p, x, y;
ctx.strokeStyle = color;
ctx.lineWidth = s * 0.5;
ctx.lineCap = "round";
ctx.lineJoin = "round";
for(i = 4; i--; ) {
p = (t + i / 4) % 1;
x = Math.floor(cx + ((i - 1.5) / 1.5) * (i === 1 || i === 2 ? -1 : 1) * a) + 0.5;
y = cy + p * cw;
line(ctx, x, y - s * 1.5, x, y + s * 1.5);
}
}
function snow(ctx, t, cx, cy, cw, s, color) {
t /= 3000;
var a = cw * 0.16,
b = s * 0.75,
u = t * TWO_PI * 0.7,
ux = Math.cos(u) * b,
uy = Math.sin(u) * b,
v = u + TWO_PI / 3,
vx = Math.cos(v) * b,
vy = Math.sin(v) * b,
w = u + TWO_PI * 2 / 3,
wx = Math.cos(w) * b,
wy = Math.sin(w) * b,
i, p, x, y;
ctx.strokeStyle = color;
ctx.lineWidth = s * 0.5;
ctx.lineCap = "round";
ctx.lineJoin = "round";
for(i = 4; i--; ) {
p = (t + i / 4) % 1;
x = cx + Math.sin((p + i / 4) * TWO_PI) * a;
y = cy + p * cw;
line(ctx, x - ux, y - uy, x + ux, y + uy);
line(ctx, x - vx, y - vy, x + vx, y + vy);
line(ctx, x - wx, y - wy, x + wx, y + wy);
}
}
function fogbank(ctx, t, cx, cy, cw, s, color) {
t /= 30000;
var a = cw * 0.21,
b = cw * 0.06,
c = cw * 0.21,
d = cw * 0.28;
ctx.fillStyle = color;
puffs(ctx, t, cx, cy, a, b, c, d);
ctx.globalCompositeOperation = 'destination-out';
puffs(ctx, t, cx, cy, a, b, c - s, d - s);
ctx.globalCompositeOperation = 'source-over';
}
/*
var WIND_PATHS = [
downsample(63, upsample(8, [
-1.00, -0.28,
-0.75, -0.18,
-0.50, 0.12,
-0.20, 0.12,
-0.04, -0.04,
-0.07, -0.18,
-0.19, -0.18,
-0.23, -0.05,
-0.12, 0.11,
0.02, 0.16,
0.20, 0.15,
0.50, 0.07,
0.75, 0.18,
1.00, 0.28
])),
downsample(31, upsample(16, [
-1.00, -0.10,
-0.75, 0.00,
-0.50, 0.10,
-0.25, 0.14,
0.00, 0.10,
0.25, 0.00,
0.50, -0.10,
0.75, -0.14,
1.00, -0.10
]))
];
*/
var WIND_PATHS = [
[
-0.7500, -0.1800, -0.7219, -0.1527, -0.6971, -0.1225,
-0.6739, -0.0910, -0.6516, -0.0588, -0.6298, -0.0262,
-0.6083, 0.0065, -0.5868, 0.0396, -0.5643, 0.0731,
-0.5372, 0.1041, -0.5033, 0.1259, -0.4662, 0.1406,
-0.4275, 0.1493, -0.3881, 0.1530, -0.3487, 0.1526,
-0.3095, 0.1488, -0.2708, 0.1421, -0.2319, 0.1342,
-0.1943, 0.1217, -0.1600, 0.1025, -0.1290, 0.0785,
-0.1012, 0.0509, -0.0764, 0.0206, -0.0547, -0.0120,
-0.0378, -0.0472, -0.0324, -0.0857, -0.0389, -0.1241,
-0.0546, -0.1599, -0.0814, -0.1876, -0.1193, -0.1964,
-0.1582, -0.1935, -0.1931, -0.1769, -0.2157, -0.1453,
-0.2290, -0.1085, -0.2327, -0.0697, -0.2240, -0.0317,
-0.2064, 0.0033, -0.1853, 0.0362, -0.1613, 0.0672,
-0.1350, 0.0961, -0.1051, 0.1213, -0.0706, 0.1397,
-0.0332, 0.1512, 0.0053, 0.1580, 0.0442, 0.1624,
0.0833, 0.1636, 0.1224, 0.1615, 0.1613, 0.1565,
0.1999, 0.1500, 0.2378, 0.1402, 0.2749, 0.1279,
0.3118, 0.1147, 0.3487, 0.1015, 0.3858, 0.0892,
0.4236, 0.0787, 0.4621, 0.0715, 0.5012, 0.0702,
0.5398, 0.0766, 0.5768, 0.0890, 0.6123, 0.1055,
0.6466, 0.1244, 0.6805, 0.1440, 0.7147, 0.1630,
0.7500, 0.1800
],
[
-0.7500, 0.0000, -0.7033, 0.0195, -0.6569, 0.0399,
-0.6104, 0.0600, -0.5634, 0.0789, -0.5155, 0.0954,
-0.4667, 0.1089, -0.4174, 0.1206, -0.3676, 0.1299,
-0.3174, 0.1365, -0.2669, 0.1398, -0.2162, 0.1391,
-0.1658, 0.1347, -0.1157, 0.1271, -0.0661, 0.1169,
-0.0170, 0.1046, 0.0316, 0.0903, 0.0791, 0.0728,
0.1259, 0.0534, 0.1723, 0.0331, 0.2188, 0.0129,
0.2656, -0.0064, 0.3122, -0.0263, 0.3586, -0.0466,
0.4052, -0.0665, 0.4525, -0.0847, 0.5007, -0.1002,
0.5497, -0.1130, 0.5991, -0.1240, 0.6491, -0.1325,
0.6994, -0.1380, 0.7500, -0.1400
]
],
WIND_OFFSETS = [
{start: 0.36, end: 0.11},
{start: 0.56, end: 0.16}
];
function leaf(ctx, t, x, y, cw, s, color) {
var a = cw / 8,
b = a / 3,
c = 2 * b,
d = (t % 1) * TWO_PI,
e = Math.cos(d),
f = Math.sin(d);
ctx.fillStyle = color;
ctx.strokeStyle = color;
ctx.lineWidth = s;
ctx.lineCap = "round";
ctx.lineJoin = "round";
ctx.beginPath();
ctx.arc(x , y , a, d , d + Math.PI, false);
ctx.arc(x - b * e, y - b * f, c, d + Math.PI, d , false);
ctx.arc(x + c * e, y + c * f, b, d + Math.PI, d , true );
ctx.globalCompositeOperation = 'destination-out';
ctx.fill();
ctx.globalCompositeOperation = 'source-over';
ctx.stroke();
}
function swoosh(ctx, t, cx, cy, cw, s, index, total, color) {
t /= 2500;
var path = WIND_PATHS[index],
a = (t + index - WIND_OFFSETS[index].start) % total,
c = (t + index - WIND_OFFSETS[index].end ) % total,
e = (t + index ) % total,
b, d, f, i;
ctx.strokeStyle = color;
ctx.lineWidth = s;
ctx.lineCap = "round";
ctx.lineJoin = "round";
if(a < 1) {
ctx.beginPath();
a *= path.length / 2 - 1;
b = Math.floor(a);
a -= b;
b *= 2;
b += 2;
ctx.moveTo(
cx + (path[b - 2] * (1 - a) + path[b ] * a) * cw,
cy + (path[b - 1] * (1 - a) + path[b + 1] * a) * cw
);
if(c < 1) {
c *= path.length / 2 - 1;
d = Math.floor(c);
c -= d;
d *= 2;
d += 2;
for(i = b; i !== d; i += 2)
ctx.lineTo(cx + path[i] * cw, cy + path[i + 1] * cw);
ctx.lineTo(
cx + (path[d - 2] * (1 - c) + path[d ] * c) * cw,
cy + (path[d - 1] * (1 - c) + path[d + 1] * c) * cw
);
}
else
for(i = b; i !== path.length; i += 2)
ctx.lineTo(cx + path[i] * cw, cy + path[i + 1] * cw);
ctx.stroke();
}
else if(c < 1) {
ctx.beginPath();
c *= path.length / 2 - 1;
d = Math.floor(c);
c -= d;
d *= 2;
d += 2;
ctx.moveTo(cx + path[0] * cw, cy + path[1] * cw);
for(i = 2; i !== d; i += 2)
ctx.lineTo(cx + path[i] * cw, cy + path[i + 1] * cw);
ctx.lineTo(
cx + (path[d - 2] * (1 - c) + path[d ] * c) * cw,
cy + (path[d - 1] * (1 - c) + path[d + 1] * c) * cw
);
ctx.stroke();
}
if(e < 1) {
e *= path.length / 2 - 1;
f = Math.floor(e);
e -= f;
f *= 2;
f += 2;
leaf(
ctx,
t,
cx + (path[f - 2] * (1 - e) + path[f ] * e) * cw,
cy + (path[f - 1] * (1 - e) + path[f + 1] * e) * cw,
cw,
s,
color
);
}
}
Skycons = function(opts) {
this.list = [];
this.interval = null;
this.color = opts && opts.color ? opts.color : "black";
this.resizeClear = !!(opts && opts.resizeClear);
};
Skycons.CLEAR_DAY = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h);
sun(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, color);
};
Skycons.CLEAR_NIGHT = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h);
moon(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, color);
};
Skycons.PARTLY_CLOUDY_DAY = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h);
sun(ctx, t, w * 0.625, h * 0.375, s * 0.75, s * STROKE, color);
cloud(ctx, t, w * 0.375, h * 0.625, s * 0.75, s * STROKE, color);
};
Skycons.PARTLY_CLOUDY_NIGHT = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h);
moon(ctx, t, w * 0.667, h * 0.375, s * 0.75, s * STROKE, color);
cloud(ctx, t, w * 0.375, h * 0.625, s * 0.75, s * STROKE, color);
};
Skycons.CLOUDY = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h);
cloud(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, color);
};
Skycons.RAIN = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h);
rain(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
cloud(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
};
Skycons.SLEET = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h);
sleet(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
cloud(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
};
Skycons.SNOW = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h);
snow(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
cloud(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
};
Skycons.WIND = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h);
swoosh(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, 0, 2, color);
swoosh(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, 1, 2, color);
};
Skycons.FOG = function(ctx, t, color) {
var w = ctx.canvas.width,
h = ctx.canvas.height,
s = Math.min(w, h),
k = s * STROKE;
fogbank(ctx, t, w * 0.5, h * 0.32, s * 0.75, k, color);
t /= 5000;
var a = Math.cos((t ) * TWO_PI) * s * 0.02,
b = Math.cos((t + 0.25) * TWO_PI) * s * 0.02,
c = Math.cos((t + 0.50) * TWO_PI) * s * 0.02,
d = Math.cos((t + 0.75) * TWO_PI) * s * 0.02,
n = h * 0.936,
e = Math.floor(n - k * 0.5) + 0.5,
f = Math.floor(n - k * 2.5) + 0.5;
ctx.strokeStyle = color;
ctx.lineWidth = k;
ctx.lineCap = "round";
ctx.lineJoin = "round";
line(ctx, a + w * 0.2 + k * 0.5, e, b + w * 0.8 - k * 0.5, e);
line(ctx, c + w * 0.2 + k * 0.5, f, d + w * 0.8 - k * 0.5, f);
};
Skycons.prototype = {
add: function(el, draw) {
var obj;
if(typeof el === "string")
el = document.getElementById(el);
obj = {
element: el,
context: el.getContext("2d"),
drawing: draw
};
this.list.push(obj);
this.draw(obj, KEYFRAME);
},
set: function(el, draw) {
var i;
if(typeof el === "string")
el = document.getElementById(el);
for(i = this.list.length; i--; )
if(this.list[i].element === el) {
this.list[i].drawing = draw;
this.draw(this.list[i], KEYFRAME);
return;
}
this.add(el, draw);
},
remove: function(el) {
var i;
if(typeof el === "string")
el = document.getElementById(el);
for(i = this.list.length; i--; )
if(this.list[i].element === el) {
this.list.splice(i, 1);
return;
}
},
draw: function(obj, time) {
var canvas = obj.context.canvas;
if(this.resizeClear)
canvas.width = canvas.width;
else
obj.context.clearRect(0, 0, canvas.width, canvas.height);
obj.drawing(obj.context, time, this.color);
},
play: function() {
var self = this;
this.pause();
this.interval = requestInterval(function() {
var now = Date.now(),
i;
for(i = self.list.length; i--; )
self.draw(self.list[i], now);
}, 1000 / 60);
},
pause: function() {
var i;
if(this.interval) {
cancelInterval(this.interval);
this.interval = null;
}
}
};
}(this));