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(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();
}
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(0, 0, radius, 0, 2*Math.PI);
ctx.fillStyle = 'white';
ctx.fill();
Create a radial gradient (95% and 105% of original clock radius):
grad = ctx.createRadialGradient(0,0,radius*0.95, 0,0,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(0, 0, radius*0.1, 0, 2*Math.PI);
ctx.fillStyle = '#333';
ctx.fill();
