mirror of
https://github.com/schibo/1964js.git
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eae23be5fc
git-svn-id: http://1964js.googlecode.com/svn/trunk@254 0378edba-076e-5dc0-2bb2-d87a714dcd81
44 lines
No EOL
1.3 KiB
CoffeeScript
44 lines
No EOL
1.3 KiB
CoffeeScript
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class C1964jsAudio
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audioContext = undefined
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audioBuffer = undefined
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constructor: ->
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processAudio: (memory, from, length) ->
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return
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try
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return if audioContext is "unsupported"
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audioContext = new webkitAudioContext() if audioContext is `undefined`
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catch error
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#log "Your browser doesn't support Web Audio."
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audioContext = "unsupported"
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return false
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PI_2_400 = 1.0 / (Math.PI * 2 * 400)
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# Create/set audio buffer for each chunk
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source = audioContext.createBufferSource()
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return if length < 4
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audioBuffer = audioContext.createBuffer(2, length / 2 / 2, 44100) if audioBuffer is `undefined`
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left = audioBuffer.getChannelData(0)
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right = audioBuffer.getChannelData(1)
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i = from
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k = 0
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while k < length
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left[k] = ((memory.rdramUint8Array[i] << 8 | memory.rdramUint8Array[i + 1]) << 16 >> 16) * PI_2_400
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right[k] = ((memory.rdramUint8Array[i + 2] << 8 | memory.rdramUint8Array[i + 3]) << 16 >> 16) * PI_2_400
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i += 4
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k++
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source.buffer = audioBuffer
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@startTime += audioBuffer.duration
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source.connect audioContext.destination
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source.loop = false
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source.noteOn @startTime
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return true
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#hack global space until we export classes properly
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#node.js uses exports; browser uses this (window)
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root = exports ? this
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root.C1964jsAudio = C1964jsAudio |