initial contrast display support

This commit is contained in:
Henry Jameson 2018-10-10 00:07:28 +03:00
parent 4d77b0c86b
commit 87e98772b0
4 changed files with 141 additions and 5 deletions

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@ -0,0 +1,64 @@
<template>
<div class="contrast-ratio">
<span class="label">
Contrast:
</span>
<span>
<span>
{{contrast.text}}
</span>
<span class="rating">
<span v-if="contrast.aaa">
AAA
</span>
<span v-if="!contrast.aaa && contrast.aa">
AA
</span>
<span v-if="!contrast.aaa && !contrast.aa">
bad
</span>
</span>
</span>
<span v-if="large">
<span>
18pt+:
</span>
<span class="rating">
<span v-if="contrast.aaa">
AAA
</span>
<span v-if="!contrast.aaa && contrast.aa">
AA
</span>
<span v-if="!contrast.aaa && !contrast.aa">
bad
</span>
</span>
</span>
</div>
</template>
<script>
export default {
props: [
'large', 'contrast'
]
}
</script>
<style lang="scss">
.contrast-ratio {
display: flex;
justify-content: end;
.label {
margin-right: 1em;
}
.rating {
display: inline-block;
min-width: 3em;
text-align: center;
}
}
</style>

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@ -1,5 +1,6 @@
import { rgb2hex } from '../../services/color_convert/color_convert.js'
import { rgb2hex, hex2rgb, getContrastRatio } from '../../services/color_convert/color_convert.js'
import ColorInput from '../color_input/color_input.vue'
import ContrastRatio from '../contrast_ratio/contrast_ratio.vue'
import OpacityInput from '../opacity_input/opacity_input.vue'
import StyleSetter from '../../services/style_setter/style_setter.js'
@ -127,7 +128,7 @@ export default {
avatarAltRadius: this.avatarAltRadiusLocal,
tooltipRadius: this.tooltipRadiusLocal,
attachmentRadius: this.attachmentRadiusLocal
}
},
}
},
preview () {
@ -143,9 +144,36 @@ export default {
}
},
previewTheme () {
if (!this.preview.theme) return { colors: {}, opacity: {}, radii: {} }
if (!this.preview.theme) return { colors: {}, opacity: {}, radii: {}, contrast: {} }
return this.preview.theme
},
previewContrast () {
if (!this.previewTheme.colors) return {}
const colors = this.previewTheme.colors
const hints = (ratio) => ({
text: ratio.toPrecision(3) + ':1',
// AA level, AAA level
aa: ratio >= 4.5,
aaa: ratio >= 7,
// same but for 18pt+ texts
laa: ratio >= 3,
laaa: ratio >= 4.5
})
const ratios = {
bgText: getContrastRatio(hex2rgb(colors.bg), hex2rgb(colors.text)),
bgLink: getContrastRatio(hex2rgb(colors.bg), hex2rgb(colors.link)),
panelText: getContrastRatio(hex2rgb(colors.panel), hex2rgb(colors.panelText)),
btnText: getContrastRatio(hex2rgb(colors.btn), hex2rgb(colors.btnText)),
topBarText: getContrastRatio(hex2rgb(colors.topBar), hex2rgb(colors.topBarText)),
topBarLink: getContrastRatio(hex2rgb(colors.topBar), hex2rgb(colors.topBarLink)),
}
return Object.entries(ratios).reduce((acc, [k, v]) => { acc[k] = hints(v); return acc }, {})
},
previewRules () {
if (!this.preview.colorRules) return ''
return [this.preview.colorRules, this.preview.radiiRules, 'color: var(--text)'].join(';')
@ -153,7 +181,8 @@ export default {
},
components: {
ColorInput,
OpacityInput
OpacityInput,
ContrastRatio
},
methods: {
exportCurrentTheme () {

View File

@ -53,7 +53,9 @@
<ColorInput name="bgColor" v-model="bgColorLocal" :label="$t('settings.background')"/>
<OpacityInput name="bgOpacity" v-model="bgOpacityLocal" :fallback="previewTheme.opacity.bg || 1"/>
<ColorInput name="textColor" v-model="textColorLocal" :label="$t('settings.text')"/>
<ContrastRatio :contrast="previewContrast.bgText"/>
<ColorInput name="linkColor" v-model="linkColorLocal" :label="$t('settings.links')"/>
<ContrastRatio :contrast="previewContrast.bgLink"/>
</div>
<div class="color-item">
<ColorInput name="fgColor" v-model="fgColorLocal" :label="$t('settings.foreground')"/>
@ -81,13 +83,16 @@
<ColorInput name="panelColor" v-model="panelColorLocal" :fallback="fgColorLocal" :label="$t('settings.background')"/>
<OpacityInput name="panelOpacity" v-model="panelOpacityLocal" :fallback="previewTheme.opacity.panel || 1"/>
<ColorInput name="panelTextColor" v-model="panelTextColorLocal" :fallback="previewTheme.colors.panelText" :label="$t('settings.links')"/>
<ContrastRatio :contrast="previewContrast.panelText" large="1"/>
<ColorInput name="panelFaintColor" v-model="panelFaintColorLocal" :fallback="previewTheme.colors.panelFaint" :label="$t('settings.faint')"/>
</div>
<div class="color-item">
<h4>Top bar</h4>
<ColorInput name="topBarColor" v-model="topBarColorLocal" :fallback="fgColorLocal" :label="$t('settings.background')"/>
<ColorInput name="topBarTextColor" v-model="topBarTextColorLocal" :fallback="previewTheme.colors.topBarText" :label="$t('settings.text')"/>
<ContrastRatio :contrast="previewContrast.topBarText"/>
<ColorInput name="topBarLinkColor" v-model="topBarLinkColorLocal" :fallback="previewTheme.colors.topBarLink" :label="$t('settings.links')"/>
<ContrastRatio :contrast="previewContrast.topBarLink"/>
</div>
<div class="color-item">
<h4>Inputs</h4>
@ -100,6 +105,7 @@
<ColorInput name="btnColor" v-model="btnColorLocal" :fallback="fgColorLocal" :label="$t('settings.background')"/>
<OpacityInput name="btnOpacity" v-model="btnOpacityLocal" :fallback="previewTheme.opacity.btn || 1"/>
<ColorInput name="btnTextColor" v-model="btnTextColorLocal" :fallback="previewTheme.colors.btnText" :label="$t('settings.text')"/>
<ContrastRatio :contrast="previewContrast.btnText"/>
</div>
<div class="color-item">
<h4>Borders</h4>

View File

@ -19,6 +19,42 @@ const rgb2hex = (r, g, b) => {
return `#${((1 << 24) + (r << 16) + (g << 8) + b).toString(16).slice(1)}`
}
// https://www.w3.org/TR/2008/REC-WCAG20-20081211/#relativeluminancedef
// https://www.w3.org/TR/2008/REC-WCAG20-20081211/relative-luminance.xml
// https://en.wikipedia.org/wiki/SRGB#The_reverse_transformation
const c2linear = (b) => {
// W3C gives 0.03928 while wikipedia states 0.04045
// what those magical numbers mean - I don't know.
// something about gamma-correction, i suppose.
// Sticking with W3C example.
const c = b / 255
if (c < 0.03928) {
return c / 12.92
} else {
return Math.pow((c + 0.055) / 1.055, 2.4)
}
}
const srgbToLinear = (srgb) => {
return 'rgb'.split('').reduce((acc, c) => { acc[c] = c2linear(srgb[c]); return acc }, {})
}
// https://www.w3.org/TR/2008/REC-WCAG20-20081211/#relativeluminancedef
// https://www.w3.org/TR/2008/REC-WCAG20-20081211/relative-luminance.xml
const relativeLuminance = (srgb) => {
const {r, g, b} = srgbToLinear(srgb)
return 0.2126 * r + 0.7152 * g + 0.0722 * b
}
// https://www.w3.org/TR/2008/REC-WCAG20-20081211/#contrast-ratiodef
const getContrastRatio = (a, b) => {
const la = relativeLuminance(a)
const lb = relativeLuminance(b)
const [l1, l2] = la > lb ? [la, lb] : [lb, la]
return (l1 + 0.05) / (l2 + 0.05)
}
const hex2rgb = (hex) => {
const result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex)
return result ? {
@ -47,5 +83,6 @@ export {
rgb2hex,
hex2rgb,
mixrgb,
rgbstr2hex
rgbstr2hex,
getContrastRatio
}