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//
Random Flag Generator
- 1-9 bands (horizontal/vertical)
- 13 colours
- 5 shapes - circle, eye, heart, star, triangle
Format: NOC(N)SH
- N - number of bands (1-9)
- O - orientation of bands (h/v)
- C(N) - N band colour indexes (0-9a-c)
- S - shape (c,f,r,s,t)(optional)
- H - shape colour index (0-9a-c)(optional)
Examples:
- 1h0 - Plain black
- 1h1sc - Vietnam
- 3h01c - Germany
- 2hb1t6 - Czechia
- 6h12c467fb - LGBT pride
- 9h012ccc210r0 - Evil eye
- 5va434acb - Green bands with circle
.flag
form
input(
type="text"
)
button.generate Shuffle
*
*::after
*::before
box-sizing border-box
body
background #bbaaab
margin 0
padding 0
form
display flex
margin auto
width 80vw
input
border none
flex-basis 50%
flex-grow 1
max-width 50%
padding 1em 0
text-align center
button
background navy
border none
color white
flex-basis 50%
flex-grow 1
padding 1em 0
.flag
border 1px solid #0008
box-shadow 0 0 5em rgba(0, 0, 0, 0.4)
display flex
flex-direction column
height 50vw
margin 2em auto
position relative
width 80vw
&--vertical
flex-direction row
&::after {
background linear-gradient(105deg, #0002, #fff1, #0002)
mix-blend-mode saturation luminosity
content ''
height 50vw
position absolute
width 100%
}
.band
flex-grow 1
.circle
border-left 36vw solid black;
border-radius 50%
position absolute
height 36vw
left 22vw
top 7vw
.icon
font-family 'Material Icons'
position: absolute;
left 17vw
top 2vw
font-size: 46vw;
.triangle
position absolute
border-color transparent transparent transparent yellow
border-style solid
border-width calc(25vw - 1px) 25vw calc(25vw - 1px) 40vw
const colours = [
'black',
'darkred',
'orangered',
'darkgreen',
'green',
'teal',
'darkslateblue',
'purple',
'mediumvioletred',
'saddlebrown',
];
const brightColours = [
'greenyellow',
'whitesmoke',
'gold',
]
const bandAmount = [1, 2, 2, 3, 3, 3, 3, 4, 4, 5];
const bandOrientation = [
'horizontal',
'vertical',
// diagonal ?
];
const shapeType = [
'circle',
'favorite',
'remove_red_eye',
'star',
'star',
'triangle',
'triangle',
'',
'',
'',
'',
'',
]
const flag = document.querySelector('.flag');
document.querySelector('.generate').addEventListener('click', (evt) => {
evt.preventDefault();
generateRandomFlag(colours);
});
document.querySelector('input').addEventListener('input', (evt) => {
const encodedString = evt.target.value;
createFlagFromString(encodedString);
});
document.addEventListener('DOMContentLoaded', () => generateRandomFlag(colours));
function clear() {
// Reset output
flag.classList.remove('flag--vertical');
while (flag.firstChild) {
flag.removeChild(flag.firstChild);
}
}
function createFlag(amount, orientation, colourList, shape) {
// Set orientation
flag.classList.add('flag--' + orientation);
// Set bands
for (let i = 0; i < amount; i += 1) {
let band = document.createElement('div');
band.className = 'band';
band.style.background = colourList.shift();
flag.appendChild(band);
}
// Set shape
if (shape) {
let shapeElement = document.createElement('div');
if (['circle', 'triangle'].indexOf(shape) !== -1) {
shapeElement.className = shape;
shapeElement.style.borderLeftColor = colourList.shift();
} else {
shapeElement.className = 'icon';
shapeElement.innerHTML = shape;
shapeElement.style.color = colourList.shift();
}
flag.appendChild(shapeElement);
}
}
function createFlagFromString(encodedString) {
const bandAmount = Number(encodedString[0]);
const bandOrientation = encodedString[1] === 'v' ? 'vertical' : 'horizontal';
const colourList = encodedString
.substring(2, 2 + bandAmount).split('')
.map(encodedColour => [...colours, ...brightColours][parseInt(encodedColour, 16)]);
let shape = encodedString.length > 2 + bandAmount
? encodedString[2 + bandAmount]
: '';
if (shape) {
const hex = encodedString[encodedString.length - 1];
const colour = [...colours, ...brightColours][parseInt(hex, 16)];
colourList.push(colour);
}
switch (shape) {
case 'c': shape = 'circle'; break;
case 'f': shape = 'favorite'; break;
case 'r': shape = 'remove_red_eye'; break;
case 's': shape = 'star'; break;
case 't': shape = 'triangle'; break;
}
// Output
clear();
createFlag(bandAmount, bandOrientation, colourList, shape)
}
function generateRandomFlag(localColours) {
clear();
// Get options
const shape = pick(shapeType);
const orientation = shape === 'triangle' ? 'horizontal' : pick(bandOrientation);
const amount = pick(bandAmount);
let availableColours = shape ? colours : [...colours, ...brightColours];
colourList = pick(availableColours, amount + !!shape);
colourList = Array.isArray(colourList) ? colourList : [colourList];
if (!!shape && Math.random() > 0.33) {
colourList[colourList.length - 1] = pick(brightColours);
}
// Output
encodeOptions(amount, orientation, colourList, shape);
createFlag(amount, orientation, colourList, shape)
}
function pick(paramList, amount = 1) {
const list = paramList.slice();
const splice = (list) => list.splice(Math.floor(Math.random() * list.length), 1)[0];
if (amount === 1) { return splice(list); }
let result = [];
for (let i = 0; i < amount; i += 1) {
result.push(splice(list));
}
return result;
}
function encodeOptions(
bandAmount,
bandOrientation,
bandColours,
shape,
) {
let encodedString = '' + bandAmount;
encodedString += bandOrientation[0];
bandColours.forEach(bandColour => {
let index = colours.indexOf(bandColour)
encodedString += index === -1
? ('abc'[brightColours.indexOf(bandColour)])
: index;
});
encodedString = shape
? encodedString.substring(0, encodedString.length - 1) + shape[0] + encodedString[encodedString.length - 1]
: encodedString;
document.querySelector('input').value = encodedString;
}
Also see: Tab Triggers