Implement math operators on Color for simple color arithmetic.

[lehni]

Allow things like mixing, averaging, etc. in a very simple way.

[frederickk]

i've added a number of simple calculation methods, perhaps if you let me know what you have in mind i can add additional calculation methods for colors it to my fork

[lehni]

Hi Frederick,

I just found it, looking good!

https://github.com/frederickk/paper.js/blob/master/src/style/Color.js

I wasn't aware of all your extensions to Paper.js. Maybe we should discuss these a bit and see which ones could make it into core?

And in order for you to avoid having to merge all the time when we do refactoring (of which a lot has happened in the past), you could write these as extensions rather than a fork:

paper.Color.inject({
    add: function(color) {
        return new Color(
            this.red + point.red,
            this.green + point.green,
            this.blue + point.blue,
            this.alpha + point.alpha
        );
    }
});

Just a thought!

I will move the ones over that I think are good, and will perhaps change the code a bit. I shall also add you to the contributors list then.

[lehni]

Just realizing, the code will need more work though, since this only works for the rgb type. We should work with components arrays instead. Will look into that.

[frederickk]

i wanted to test my additions before submitting a pull request, but maybe i can just submit it and together we can possibly work on changes. let me know what you think is best.

the "library" (https://github.com/frederickk/frederickkPaper) i built was a series of extensions exactly as you've described, here... would that a better way of proposing additions for you to implement?

so a component version would look like (pseudo code):

    add: function(color) {
        for( var i=0; i<this.comps.length; i++ ) {
            this.comps[i] + color.comps[i];
        }
        return this;
    }

[lehni]

Implemented, with tests: https://github.com/paperjs/paper.js/blob/d369984196b20b72f3582d6e4bccd98fc804e0a5/src/style/Color.js#L1047

[lehni]

Oops, I didn't see you posted in the meantime. The code is more abstract, as it can produce the math operators in a loop. It also performs some extra magic so that color.multiply(4) actually works, and 4 is not clamped down to 1 before it's multiplied...