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@RyanBalfanz
Created January 2, 2019 20:59
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Save RyanBalfanz/f3901b9555db1d757b17ce961b937741 to your computer and use it in GitHub Desktop.
Analog Clock for ARTIFACT
<!DOCTYPE html>
<html>
<body>
<canvas id="canvas" width="400" height="300" style="background-color:#333"></canvas>
<script>
console.info('Adapted for ARTIFACT from https://www.w3schools.com/graphics/canvas_clock_start.asp');
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
var radius = canvas.height / 2;
ctx.translate(radius + 50, radius);
radius = radius * 0.90;
setInterval(drawClock, 1000);
drawClock();
function drawClock() {
console.log('drawing clock');
drawFace(ctx, radius);
drawNumbers(ctx, radius);
drawTime(ctx, radius);
}
function drawFace(ctx, radius) {
var grad;
ctx.beginPath();
ctx.arc(0, 0, radius, 0, 2 * Math.PI);
ctx.fillStyle = 'white';
ctx.fill();
grad = ctx.createRadialGradient(0, 0, radius * 0.95, 0, 0, radius * 1.05);
grad.addColorStop(0, '#333');
grad.addColorStop(0.5, 'white');
grad.addColorStop(1, '#333');
ctx.strokeStyle = grad;
ctx.lineWidth = radius * 0.1;
ctx.stroke();
ctx.beginPath();
ctx.arc(0, 0, radius * 0.1, 0, 2 * Math.PI);
ctx.fillStyle = '#333';
ctx.fill();
}
function drawNumbers(ctx, radius) {
var ang;
var num;
ctx.font = radius * 0.15 + "px arial";
ctx.textBaseline = "middle";
ctx.textAlign = "center";
for (num = 1; num < 13; num++) {
ang = num * Math.PI / 6;
ctx.rotate(ang);
ctx.translate(0, -radius * 0.85);
ctx.rotate(-ang);
ctx.fillText(num.toString(), 0, 0);
ctx.rotate(ang);
ctx.translate(0, radius * 0.85);
ctx.rotate(-ang);
}
}
function drawTime(ctx, radius) {
var now = new Date();
var hour = now.getHours();
var minute = now.getMinutes();
hour = hour % 12;
hour = (hour * Math.PI / 6) +
(minute * Math.PI / (6 * 60));
drawHand(ctx, hour, radius * 0.5, radius * 0.07);
minute = (minute * Math.PI / 30);
drawHand(ctx, minute, radius * 0.8, radius * 0.07);
}
function drawHand(ctx, pos, length, width) {
ctx.beginPath();
ctx.lineWidth = width;
ctx.lineCap = "round";
ctx.moveTo(0, 0);
ctx.rotate(pos);
ctx.lineTo(0, -length);
ctx.stroke();
ctx.rotate(-pos);
}
</script>
</body>
</html>
@RyanBalfanz
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This ARTIFACT app was adapted from the Canvas Clock example at W3Schools.

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