# Graphics Color questions

• ...and here is the same in a touchable version:

``````  let ColorList = [
'#0000FF', '#8000FF', '#FF00FF', '#FF0080', '#FF0000', '#FF8000',
'#FFFF00', '#80FF00', '#00FF00', '#00FF80', '#00FFFF', '#0080FF'
];

let ScreenWidth  = g.getWidth(),  CenterX = ScreenWidth/2;
let ScreenHeight = g.getHeight(), CenterY = ScreenHeight/2;

let outerRadius = Math.min(CenterX,CenterY) * 0.9;

let sin = Math.sin, cos = Math.cos;
let twoPi = 2*Math.PI, halfPi = Math.PI/2;

let DeltaPhi = twoPi/72;
let Epsilon  = 0.001;

g.clear();

g.setColor(0,0,0);
g.fillRect(0,0, ScreenWidth,ScreenHeight);

for (let i = 0; i < 12; i++) {
let Phi0 = i * twoPi/12, Phi1 = (i+1) * twoPi/12;

let Polygon = [];
for (let Phi = Phi0; Phi <= Phi1+Epsilon; Phi += DeltaPhi) {
}

for (let Phi = Phi1; Phi >= Phi0-Epsilon; Phi -= DeltaPhi) {
}
g.setColor(ColorList[i]);
g.fillPoly(Polygon);
}

g.setColor(1,1,1);

g.setFont12x20();
g.setFontAlign(0,0);
g.setColor(0,0,0);

g.drawString('Tap',   CenterX,CenterY-20);
g.drawString('on',    CenterX,CenterY);
g.drawString('Color', CenterX,CenterY+20);

Bangle.on('touch', function (Button,Position) {
let dx = Position.x - CenterX;
let dy = Position.y - CenterY;

let Radius = Math.sqrt(dx*dx + dy*dy);

let Color;
switch (true) {
default:
let Phi = Math.atan2(dy,dx) + halfPi;
if (Phi < 0)     { Phi += twoPi; }
if (Phi > twoPi) { Phi -= twoPi; }

let Index = Math.floor(12*Phi/twoPi);
Color = ColorList[Index];
}
g.setColor(1,1,1);