By Zevan | August 28, 2018
I have a set of ~100 pictograms that I use for personal notation. When I was actively working on Zeta. I created a few of these with equations:
You can read more about Zeta in this post.
I spam my facebook with images from my sketchbooks if you’re at all interested in seeing more pictograms:

By Zevan | August 26, 2018
Creating a dictionary type object with ES6 Symbols is easy. Yes we have Maps and WeakMaps but this is still interesting for a variety of reasons… Being able to use objects as keys in another object (dictionary) has many great uses…. So how do you use Symbols like this?
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| let a = { id: Symbol('key') },
b = { id: Symbol('key') };
let dictionary = {
[a.id]: 'value by obj a',
[b.id]: 'value by obj b'
};
console.log(dictionary[a.id]);
console.log(dictionary[b.id]);
// outputs:
// 'value by obj a'
// 'value by obj b' |
By using either object a or object b’s `id` symbol, our dictionary points to another value. This old AS3 snippet is similar:
http://actionsnippet.com/?p=426
By Zevan | August 18, 2018
In 2015 I created QuickShader… which just takes the boilerplate out of showing a shader in the browser. Here are a few examples:
By Zevan | August 18, 2018
Being able to draw smooth lines that connect arbitrary points is something that I find myself needing very frequently. This is a port of an old snippet that does just that. By averaging control points of a quadratic bezier curve we ensure that our resulting Bezier curves are always smooth.
The key can be seen here with the `bezierSkin` function. It draws either a closed or open curve.
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| // array of xy coords, closed boolean
function bezierSkin(bez, closed = true) {
var avg = calcAvgs(bez),
leng = bez.length,
i, n;
if (closed) {
c.moveTo(avg[0], avg[1]);
for (i = 2; i < leng; i += 2) {
n = i + 1;
c.quadraticCurveTo(bez[i], bez[n], avg[i], avg[n]);
}
c.quadraticCurveTo(bez[0], bez[1], avg[0], avg[1]);
} else {
c.moveTo(bez[0], bez[1]);
c.lineTo(avg[0], avg[1]);
for (i = 2; i < leng - 2; i += 2) {
n = i + 1;
c.quadraticCurveTo(bez[i], bez[n], avg[i], avg[n]);
}
c.lineTo(bez[leng - 2], bez[leng - 1]);
}
}
// create anchor points by averaging the control points
function calcAvgs(p) {
var avg = [],
leng = p.length, prev;
for (var i = 2; i < leng; i++) {
prev = i - 2;
avg.push((p[prev] + p[i]) / 2);
}
// close
avg.push((p[0] + p[leng - 2]) / 2);
avg.push((p[1] + p[leng - 1]) / 2);
return avg;
} |
The control points are then averaged to ensure that the curve contains no sharp angles.