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Canvas Clock Face


Part II - Draw a Clock Face

The clock needs a clock face. Create a JavaScript function to draw a clock face:

JavaScript:

function drawClock() {
    drawFace(ctx, radius);
}

function drawFace(ctx, radius) {
    var grad;

    ctx.beginPath();
    ctx.arc(00, radius, 02*Math.PI);
    ctx.fillStyle = 'white';
    ctx.fill();

    grad = ctx.createRadialGradient(0,0,radius*0.950,0,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(00, radius*0.102*Math.PI);
    ctx.fillStyle = '#333';
    ctx.fill();
}
Try it Yourself »


Code Explained

Create a drawFace() function for drawing the clock face:
function drawClock() {
    drawFace(ctx, radius);
}

function drawFace(ctx, radius) {
}
Draw the white circle:
ctx.beginPath();
ctx.arc(00, radius, 02*Math.PI);
ctx.fillStyle = 'white';
ctx.fill();
Create a radial gradient (95% and 105% of original clock radius):
grad = ctx.createRadialGradient(0,0,radius*0.950,0,radius*1.05);
Create 3 color stops, corresponding with the inner, middle, and outer edge of the arc:
grad.addColorStop(0'#333');
grad.addColorStop(0.5'white');
grad.addColorStop(1'#333');
The color stops create a 3D effect.
Define the gradient as the stroke style of the drawing object:
ctx.strokeStyle = grad;
Define the line width of the drawing object (10% of radius):
ctx.lineWidth = radius * 0.1;
Draw the circle:
ctx.stroke();
Draw the clock center:
ctx.beginPath();
ctx.arc(00, radius*0.102*Math.PI);
ctx.fillStyle = '#333';
ctx.fill();

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