Question

Is it possible to subtract a color from another one ?

Example (correct me if i’m wrong):

If i subtract red and green from white, i am expecting the
result to be blue.

var white = 0xFFFFFF,
    red = 0xFF0000,
    result = white - red;
console.log(result); //65535 <-- what is that ? can it be converted to 0x00FFFF ?

[update]

Thanks to Rocket’s answer, it turned out i needed a function() to convert my results into an actual color.

Here is the final working example:

var toColor = function ( d ) {
       var c = Number(d).toString(16);
       return "#" + ( "000000".substr( 0, 6 - c.length ) + c.toUpperCase() );
    },
    white = 0xFFFFFF,
    red = 0xFF0000,
    green = 0x00FF00,
    result = toColor( white - red - green );

console.log( result ); // logs the expected result: "#0000FF"

Answer 1

Your white-red works fine, it’s just that JavaScript represents the values as base 10 values. You need to convert them back to base 16 (hex). Check out this answer, to convert the value back to hex.

var white = 0xFFFFFF, // Stored as 16777215
    red = 0xFF0000, // Stored as 16711680
    result = white - red; // 16777215 - 16711680 = 65535
console.log(result); // It's stored as base 10, so it prints 65535
var resultHex = result.toString(16); // 'ffff', converted back to hex