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Javascript functions for doing fast binary/hex/RGB color conversions using bitwise operations.
// convert 0..255 R,G,B values to binary string
RGBToBin = function(r,g,b){
var bin = r << 16 | g << 8 | b;
return (function(h){
return new Array(25-h.length).join("0")+h
})(bin.toString(2))
}
// convert 0..255 R,G,B values to a hexidecimal color string
RGBToHex = function(r,g,b){
var bin = r << 16 | g << 8 | b;
return (function(h){
return new Array(7-h.length).join("0")+h
})(bin.toString(16).toUpperCase())
}
// convert a 24 bit binary color to 0..255 R,G,B
binToRGB = function(bin){
var pbin = parseInt(bin,2);
var r = pbin >> 16;
var g = pbin >> 8 & 0xFF;
var b = pbin & 0xFF;
return [r,g,b];
}
// convert a hexidecimal color string to 0..255 R,G,B
hexToRGB = function(hex){
var r = hex >> 16;
var g = hex >> 8 & 0xFF;
var b = hex & 0xFF;
return [r,g,b];
}
// simple log function for web/nodejs
log = function(item){
if (document.body){
document.body.innerHTML = document.body.innerHTML+'<pre>'+item+'</pre>';
} else {
console.log(item);
}
}
// convert some RGB color values to hex and to binary
new Array(
[000,000,000], // black
[000,255,000], // green
[255,255,255] // white
).forEach(function(rgb){
var hex = RGBToHex(rgb[0],rgb[1],rgb[2]);
var bin = RGBToBin(rgb[0],rgb[1],rgb[2]);
log('-> RGB: '+rgb+' \n<- HEX: '+hex+' \n<- BIN: '+bin+'\n\n');
});
// convert some hexidecimal color values to RGB
new Array(
'000000', // black
'00FF00', // green
'FFFFFF' // white
).forEach(function(hex){
var rgb = hexToRGB(parseInt(hex,16));
log('-> HEX: '+hex+' \n<- RGB: '+rgb+'\n\n');
});
// convert some 24 bit binary color values to RGB
new Array(
'000000000000000000000000', // black
'000000001111111100000000', // green
'111111111111111111111111' // white
).forEach(function(bin){
var rgb = binToRGB(bin);
log('-> BIN: '+bin+' \n<- RGB: '+rgb+'\n\n');
});
@thednp

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commented Oct 12, 2014

Does the hexToRGB function do shorthex values as well?

UPDATE, it does not. I would suggest to do a check if length is less than 7 characters, if not duplicate each alphanumeric.

@un-quebec-independant

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commented May 5, 2016

the hex needs to start with "0x", for those who couldn't get it working

@LJNeon

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commented Feb 3, 2018

Array(7-h.length).join("0") can be replaced with "0".repeat(6-h.length)

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