RobinNixon
71 lines
1.5 KiB
HTML
71 lines
1.5 KiB
HTML
<!DOCTYPE html>
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<html>
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<head>
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<title>Drawing Arcs</title>
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<script src='OSC.js'></script>
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</head>
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<body>
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<canvas id='mycanvas' width='640' height='480'></canvas>
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<script>
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canvas = O('mycanvas')
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context = canvas.getContext('2d')
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S(canvas).background = 'lightblue'
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context.lineWidth = 2
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context.strokeStyle = 'blue'
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Math.degreesToRadians = function(degrees)
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{
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return degrees * Math.PI / 180
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}
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arcs =
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[
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Math.PI,
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Math.PI * 2,
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Math.PI / 2,
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Math.PI / 180 * 59
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]
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// This code below uses degrees as arguments as shown
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// later in the chapter
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// arcs =
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// [
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// Math.degreesToRadians(180),
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// Math.degreesToRadians(360),
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// Math.degreesToRadians(90),
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// Math.degreesToRadians(59)
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// ]
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for (j = 0 ; j < 4 ; ++j)
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{
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context.beginPath()
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context.arc(80 + j * 160, 80, 70, 0, arcs[j])
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context.closePath()
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context.stroke()
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}
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context.strokeStyle = 'red'
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for (j = 0 ; j < 4 ; ++j)
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{
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context.beginPath()
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context.arc(80 + j * 160, 240, 70, 0, arcs[j])
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context.stroke()
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context.closePath()
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}
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context.strokeStyle = 'green'
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for (j = 0 ; j < 4 ; ++j)
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{
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context.beginPath()
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context.arc(80 + j * 160, 400, 70, 0, arcs[j], true)
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context.stroke()
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context.closePath()
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}
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</script>
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</body>
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</html>
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