How about a color picker in AI2 like this one without using gradient calculations?

I got bored of having to move three sliders to achieve the color I want. I like how you select colors with the hue color picker in Photoshop and I realized that some areas are always the same, and only the top right corner changes when selecting a different color in the spectrum palette.
So I tried a couple of things until it worked just like I wanted. There's a lot of things that can be added, but the basic picker works just fine.
This image explains how I did it. It's simpler than it looks.

Here's the Gallery link to open it:
ai2.appinventor.mit.edu/?galleryId=4859625112862720