1
1
mirror of https://github.com/rsms/inter.git synced 2024-12-01 04:20:46 +03:00
inter/docs/dynmetrics/index.html
2018-10-10 23:38:33 -07:00

603 lines
17 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

---
layout: default
title: Dynamic Metrics
---
{%
capture url_root
%}{% if site.safe == false %}/{% else %}/inter/{% endif
%}{%
endcapture %}{%
for file in site.static_files %}{%
assign _path = file.path | remove_first: "/inter" %}{%
if _path == "/dynmetrics/index.css" %}{%
assign index_css_v = file.modified_time | date: "%Y%m%d%H%M%S" %}{%
elsif _path == "/res/bindings.js" %}{%
assign bindings_js_v = file.modified_time | date: "%Y%m%d%H%M%S" %}{%
elsif _path == "/res/graphplot.js" %}{%
assign graphplot_js_v = file.modified_time | date: "%Y%m%d%H%M%S" %}{%
endif %}{%
endfor
%}
<link rel="stylesheet" href="index.css?v={{ index_css_v }}">
<script src="{{url_root}}res/bindings.js?v={{ bindings_js_v }}"></script>
<script src="{{url_root}}res/graphplot.js?v={{ graphplot_js_v }}"></script>
<div class="row first"><div>
<h1>Dynamic Metrics</h1>
<p>
There's of course no absolute right or wrong when it comes to expressing
yourself with typography, but Inter UI Dynamic Metrics provides guidelines
for how to best use Inter UI.
You simply provide the optical font size,
and the tracking and leading is calculated for you through the following
formula:
</p>
<p>
<formula>
tracking =
<const>a</const> + <const>b</const> ×
<const title="Base of natural logarithm; ≈2.718">e</const><sup>(<const>c</const> × <const>z</const>)</sup>
</formula>
<formula>
leading = round(<num data-binding="var-l">1.4</num> × <const>z</const>)
</formula>
<formula title="Values for Inter UI">
<g><const title="Constant a">a</const> = <num data-binding="var-a">-0.016</num></g> &nbsp;&nbsp;
<g><const title="Constant b">b</const> = <num data-binding="var-b">0.21</num></g> &nbsp;&nbsp;
<g><const title="Constant c">c</const> = <num data-binding="var-c">-0.18</num></g> &nbsp;&nbsp;
<g><const>z</const> = font size</g>
</formula>
</p>
<p class="wide-window">
The controls below can be used to play around with the
<const>a</const>, <const>b</const> and <const>c</const> constants to discover
how they affect tracking.
</p>
<p class="narrow-window">
<small>View this on a larger screen to enable interactive control.</small>
</p>
</div></div>
<div class="white full-width row with-sidebar">
<div class="samples">
<p class="sample">
<span class="di"><span></span></span>
<span class="info"
title="size, tracking, (ideal tracking) — progress bar shows distance from ideal"
>15 &nbsp; 0.0 &nbsp; ( 0.0 )</span>
<span contenteditable class="content">
Such a riot of sea and wind strews the whole extent of beach with whatever has been lost or thrown overboard, or torn out of sunken ships. Many a man has made a good weeks work in a single day by what he has found while walking along the Beach when the surf was down.
</span>
</p>
</div>
<div class="sidebar controls">
<div class="control">
<label title="Number of ideal matches">ni</label>
<input title="Number of ideal matches" type="number" readonly data-binding="ideal-count">
<label title="Distance from ideal">di</label>
<input title="Distance from ideal" type="number" class="wide" readonly data-binding="ideal-distance">
</div>
<div class="control">
<img title="Style" class="icon" src="../samples/icons/style.svg">
<select data-binding="style">
<option value="regular" default>Regular</option>
<option value="italic">Italic</option>
<option value="medium" default>Medium</option>
<option value="medium-italic">Medium Italic</option>
<option value="semi-bold" default>Semi Bold</option>
<option value="semi-bold-italic">Semi Bold Italic</option>
<option value="bold" default>Bold</option>
<option value="bold-italic">Bold Italic</option>
<option value="extra-bold" default>Extra Bold</option>
<option value="extra-bold-italic">Extra Bold Italic</option>
<option value="black" default>Black</option>
<option value="black-italic">Black Italic</option>
</select>
</div>
<div class="control">
<img title="Base tracking" class="icon" src="../samples/icons/letter-spacing.svg">
<input type="range" min="-0.05" max="0.06" step="0.001" data-binding="base-tracking">
<input type="number" min="-0.15" max="1" step="0.001" data-binding="base-tracking">
</div>
<hr>
<div class="control">
<label title="Constant a">a</label>
<input type="range" min="-0.05" max="0" step="0.001" data-binding="var-a">
<input type="number" min="-0.05" max="0" step="0.0001" data-binding="var-a">
</div>
<div class="control">
<label title="Constant b">b</label>
<input type="range" min="0" max="1" step="0.01" data-binding="var-b">
<input type="number" min="0" max="1" step="0.001" data-binding="var-b">
</div>
<div class="control">
<label title="Constant c">c</label>
<input type="range" min="-1" max="0" step="0.01" data-binding="var-c">
<input type="number" min="-1" max="0" step="0.001" data-binding="var-c">
</div>
<hr>
<div class="control">
<label title="Constant l controls line height">l</label>
<input type="range" min="1" max="2" step="0.1" data-binding="var-l">
<input type="number" min="1" max="2" step="0.1" data-binding="var-l">
</div>
<hr class="without-bottom-margin">
<canvas class="graphplot">Canvas not Supported</canvas>
<hr class="when-selection without-top-margin">
<h3 class="when-selection">CSS</h3>
<textarea class="when-selection" readonly id="code-output"></textarea>
<hr class="without-top-margin">
<h3>Ideal values</h3>
<textarea id="ideal-values"></textarea>
<hr class="without-top-margin">
</div>
</div>
<script type="text/javascript">(function(){
// internal variables that are user-controllable, but are not part of
// Dynamic Metrics
var baseTracking = 0
var weightClass = 400
function round(num, prec) {
return parseFloat(num.toFixed(prec))
}
// Ideal values designed one by one, by hand.
// font size => tracking
var idealValues = {}
var idealValuesList = []
var idealValuesTextArea = $('textarea#ideal-values')
function setIdealValues(valueMap) {
idealValues = valueMap
idealValuesList = []
Object.keys(idealValues).forEach(function(fontSize) {
idealValuesList.push([fontSize, idealValues[fontSize]])
})
if (idealValuesTextArea.value == '') {
idealValuesTextArea.value = idealValuesList.map(function(t){
return t[0] + '\t' + t[1]
}).join('\n')
}
}
function parseValues(s) {
var values = {}
s = s.replace(/^[\s\r\t\n]+|[\s\r\t\n]+$/g, '') // trim whitespace
s.split(/\s*\r?\n\s*/).map(function(line) {
var t = line.split(/\s+/)
if (t.length == 2) {
t[0] = parseInt(t[0])
t[1] = parseFloat(t[1])
values[t[0]] = t[1]
}
})
return values
}
setIdealValues({
// 2018-09-28
6: 0.054,
7: 0.042,
8: 0.033,
9: 0.025,
10: 0.018,
11: 0.012,
12: 0.008,
13: 0.004,
14: 0,
15: -0.002,
16: -0.005,
17: -0.007,
18: -0.008,
20: -0.011,
24: -0.014,
30: -0.016,
40: -0.017,
})
// Variables for constants involved in Dynamic Metrics
// var a = -0.012, b = 0.23, c = -0.21; // di=0.002514 on set-2018-02-18
// var a = -0.013, b = 0.251, c = -0.222 // di=0.001742 on set-2018-02-18
// var a = -0.015, b = 0.283, c = -0.23; // di=0.00221 on set-2018-02-18
// var a = -0.0149, b = 0.298, c = -0.23; // di=0.000484 on set-2018-02-19
// var a = -0.018, b = 0.21, c = -0.18; // di=0.000532 on set-2018-02-20
var a = -0.017, b = 0.202, c = -0.175; // di=0.000247 on 2018-09-28
var l = 1.4
// _InterUIDynamicTracking is a version of InterUIDynamicTracking that
// uses some global variables that are adjustable.
//
function _InterUIDynamicTracking(fontSize, weightClass) {
// Note: weightClass is currently unused
//
// y = -0.01021241 + 0.3720623 * e ^ (-0.2808687 * x)
// [6-35] 0.05877 .. -0.0101309 (13==0; stops growing around 30-35)
// See https://gist.github.com/rsms/8efdbca5f8145a584ed08a7c3d6e5788
//
return a + b * Math.pow(Math.E, c * fontSize)
// [6 - 38] 0.05798 .. -0.01099 (midpoint = 12.533)
//
// y = 0.025 - (ln(x) * 0.01)
// return 0.025 - Math.log(fontSize) * 0.01
}
function InterUIDynamicLineHeight(fontSize, weightClass) {
return Math.round(fontSize * l)
}
var NPOS = Number.MAX_SAFE_INTEGER
function Sample(fontSize) {
this.rootEl = sampleTemplate.cloneNode(true)
this.infoEl = $('.info', this.rootEl)
this.contentEl = $('.content', this.rootEl)
this.diEl = $('.di', this.rootEl)
this.diEl.classList.add('unavailable')
this.style = this.rootEl.style
this.maxBoxWidth = 0
this.fontSize = 0
this.tracking = 0
this.lineHeight = 0
this.idealTracking = NPOS
this.matchesIdeal = false
this.setFontSize(fontSize)
this.render()
// listen for focus events on the editable content
var s = this
this.contentEl.addEventListener(
'focus',
function(){ s.onReceivedFocus() },
{passive:true, capture:false}
)
this.contentEl.addEventListener(
'blur',
function(){ s.onLostFocus() },
{passive:true, capture:false}
)
}
Sample.prototype.onReceivedFocus = function() {}
Sample.prototype.onLostFocus = function() {}
Sample.prototype.idealDistance = function(fontSize) {
// returns the distance from the ideal (or NPOS if no "ideal" data available)
if (this.idealTracking == NPOS) {
return NPOS
}
return (
Math.max(this.tracking, this.idealTracking) -
Math.min(this.tracking, this.idealTracking)
)
}
Sample.prototype.setFontSize = function(fontSize) {
this.fontSize = fontSize
this.tracking = baseTracking + _InterUIDynamicTracking(fontSize, weightClass)
this.lineHeight = InterUIDynamicLineHeight(fontSize, weightClass)
this.maxBoxWidth = Math.round(fontSize * (this.tracking + 1) * 25)
var idealTracking = idealValues[this.fontSize]
if (idealTracking === undefined) {
if (this.idealTracking != NPOS) {
this.diEl.classList.add('unavailable')
}
this.idealTracking = NPOS
this.matchesIdeal = false
} else {
if (this.idealTracking == NPOS) {
this.diEl.classList.remove('unavailable')
}
this.idealTracking = idealTracking
// match to a precision of 3
this.matchesIdeal = this.tracking.toFixed(3) == idealTracking.toFixed(3)
var di = 1
if (this.matchesIdeal) {
this.diEl.classList.add('match')
} else {
this.diEl.classList.remove('match')
di = 1 - Math.min(1, this.idealDistance() * 50)
}
this.diEl.firstChild.style.width = (di * this.maxBoxWidth) + 'px'
}
}
Sample.prototype.cssProperties = function() {
return [
['font-size', round(this.fontSize, 3) + 'px'],
['letter-spacing', round(this.tracking, 3) + 'em'],
['line-height', round(this.lineHeight, 3) + 'px'],
]
}
Sample.prototype.render = function() {
this.style.fontSize = this.fontSize + 'px'
this.style.letterSpacing = this.tracking + 'em'
this.style.lineHeight = this.lineHeight + 'px'
var SP = '\u00A0\u00A0\u00A0'
this.infoEl.innerText = (
this.fontSize +
SP + this.tracking.toFixed(3) +
// SP + this.lineHeight.toFixed(3) +
(
this.idealTracking != NPOS ? (
SP + '( ' + this.idealTracking +
(this.matchesIdeal ? ' \u2713' : '') +
' )'
) : ''
)
)
this.style.maxWidth = this.maxBoxWidth + 'px'
}
var bindings = new Bindings()
var samplesEl = $('.samples')
var sampleTemplate
var samples = [] // Sample[]
var focusedSample = null // Sample | null
var graph = new GraphPlot($('canvas.graphplot'))
graph.setOrigin(-0.2, 0.8)
graph.setScale(0.049, 5)
function addChildren(targetNode, children) {
targetNode.style.visibility = 'hidden'
var i = 0;
for (; i < children.length; i++) {
targetNode.appendChild(children[i])
}
targetNode.style.visibility = null
}
function initSamples() {
sampleTemplate = $('.sample', samplesEl)
samplesEl.removeChild(sampleTemplate)
// small and medium sizes
var i, fontSize = 6, endFontSize = 16
for (; fontSize <= endFontSize; fontSize++) {
samples.push(new Sample(fontSize))
}
// a few select large samples
samples.push(new Sample(17))
samples.push(new Sample(18))
samples.push(new Sample(20))
samples.push(new Sample(24))
samples.push(new Sample(30))
samples.push(new Sample(40))
// connect focus events
var onSampleReceivedFocus = function() { setSelectedSample(this) }
samples.forEach(function(s) {
s.onReceivedFocus = onSampleReceivedFocus
})
// add to dom in one go
addChildren(samplesEl, samples.map(function(s) { return s.rootEl }))
}
function setSelectedSample(sample) {
if (focusedSample !== sample) {
if (focusedSample) {
focusedSample.rootEl.classList.remove('selected')
}
if (sample) {
sample.rootEl.classList.add('selected')
}
focusedSample = sample
updateSelection()
}
}
function updateSample(sample) {
sample.setFontSize(sample.fontSize) // updates derived values
sample.render()
}
function updateSamples() {
samples.forEach(updateSample)
updateIdealMatches()
updateGraphPlot()
updateCodeView()
}
function updateIdealMatches() {
// ideal-distance
var idealCount = 0
var distance = 0
var ndistances = 0
samples.forEach(function(sample) {
if (sample.matchesIdeal) {
idealCount++
}
var di = sample.idealDistance()
if (di != NPOS) {
distance += di
ndistances++
}
})
distance = distance / ndistances
bindings.setValue('ideal-distance', distance.toFixed(6))
bindings.setValue('ideal-count', idealCount)
}
function updateGraphPlot() {
graph.clear()
graph.plotLine(idealValuesList, '#0d3')
graph.plotf(function(x) {
return _InterUIDynamicTracking(x, weightClass)
})
if (focusedSample) {
var graphedFontSize = Math.min(24, focusedSample.fontSize) // clamp to [-inf,24]
graph.plotPoints([
[graphedFontSize, focusedSample.tracking]
], 'rgb(45, 143, 255)')
}
}
var codeOutput = $('#code-output')
codeOutput.addEventListener('focus', function(ev) {
ev.preventDefault()
ev.stopPropagation()
codeOutput.select()
}, {passive:false,capture:true})
codeOutput.addEventListener('pointerdown', function(ev) {
// TODO: don't do this if codeOutput is focused
ev.preventDefault()
ev.stopPropagation()
codeOutput.select()
document.execCommand("copy")
HUDNotification.show('Copied to clipboard')
}, {passive:false,capture:true})
function updateCodeView() {
var s = ''
if (focusedSample) {
var props = focusedSample.cssProperties()
props.forEach(function(prop, i) {
var name = prop[0], value = prop[1]
s += name + ': ' + value + ';'
if (i != props.length-1) {
s += '\n'
}
})
}
codeOutput.value = s
}
function updateSelection() {
var controlsEl = $('.controls')
if (focusedSample) {
controlsEl.classList.add('has-selected-sample')
} else {
controlsEl.classList.remove('has-selected-sample')
}
updateGraphPlot()
updateCodeView()
}
bindings.configure('base-tracking', 0, 'float', function (tracking) {
baseTracking = tracking
updateSamples()
})
bindings.configure('var-a', a, 'float', function (v) {
a = v
updateSamples()
})
bindings.configure('var-b', b, 'float', function (v) {
b = v
updateSamples()
})
bindings.configure('var-c', c, 'float', function (v) {
c = v
updateSamples()
})
bindings.configure('var-l', l, 'float', function (v) {
l = v
updateSamples()
})
bindings.configure('ideal-count', 0, 'int', function (v) {})
bindings.configure('ideal-distance', 0, 'float', function (v) {})
bindings.configure('style', null, null, function (style) {
var cl = samplesEl.classList
cl.remove('font-style-regular')
cl.remove('font-style-italic')
cl.remove('font-style-medium')
cl.remove('font-style-medium-italic')
cl.remove('font-style-semi-bold')
cl.remove('font-style-semi-bold-italic')
cl.remove('font-style-bold')
cl.remove('font-style-bold-italic')
cl.remove('font-style-extra-bold')
cl.remove('font-style-extra-bold-italic')
cl.remove('font-style-black')
cl.remove('font-style-black-italic')
cl.add('font-style-' + style)
weightClass = (
style.indexOf('black') != -1 ? 900 :
style.indexOf('bold') != -1 ? 700 :
style.indexOf('medium') != -1 ? 500 :
400
)
updateSamples()
})
bindings.bindAllInputs('[data-binding]')
// double-click base tracking to reset
$('input[type="range"][data-binding="base-tracking"]').addEventListener(
'dblclick',
function(ev) { bindings.setValue('base-tracking', 0) }
)
;[
['var-a',a],
['var-b',b],
['var-c',c],
['var-l',l],
['base-tracking', 0]
].forEach(p => {
let bindname = p[0], defval = p[1]
$$('input[type="range"][data-binding="'+bindname+'"]').forEach(e => {
e.addEventListener('dblclick', ev =>
bindings.setValue(bindname, defval))
})
})
// allow editing of ideal values
idealValuesTextArea.addEventListener('input', function(ev) {
setIdealValues(parseValues(idealValuesTextArea.value))
updateSamples()
})
// listen for clicks onto "background", to deselect any selected sample
document.body.addEventListener('pointerdown', function(ev){
if (
ev.target === document.body ||
ev.target === samplesEl ||
ev.target.classList && ev.target.classList.contains('row')
) {
setSelectedSample(null)
}
})
// start
initSamples()
updateSamples()
})();</script>