'From Squeak3.2gamma of 15 January 2002 [latest update: #4811] on 25 July 2002 at 11:41:53 pm'!
Object subclass: #SineWaveGenerator
	instanceVariableNames: 'magnitude step current initialPhase '
	classVariableNames: ''
	poolDictionaries: ''
	category: 'Sound-Waves'!

!SineWaveGenerator methodsFor: 'initialize' stamp: 'tf 7/25/2002 21:25'!
initialPhase:phase

	initialPhase _ phase.! !

!SineWaveGenerator methodsFor: 'initialize' stamp: 'tf 7/25/2002 21:27'!
initialize

	initialPhase _ 0.0.
	magnitude _ 1.0.
	step _ 1.0.
	current _ initialPhase.! !

!SineWaveGenerator methodsFor: 'initialize' stamp: 'tf 7/25/2002 21:24'!
magnitude:aMagnitude

	magnitude _ aMagnitude.
! !

!SineWaveGenerator methodsFor: 'initialize' stamp: 'tf 7/25/2002 21:25'!
oneCycle:oneCycle

	step _ (360 /oneCycle) asFloat.
! !

!SineWaveGenerator methodsFor: 'initialize' stamp: 'tf 7/25/2002 21:24'!
step:aStep

	step _ aStep.! !


!SineWaveGenerator methodsFor: 'accessing' stamp: 'tf 7/25/2002 21:28'!
initialPhase

	^initialPhase! !

!SineWaveGenerator methodsFor: 'accessing' stamp: 'tf 7/25/2002 21:28'!
magnitude

	^magnitude! !

!SineWaveGenerator methodsFor: 'accessing' stamp: 'tf 7/25/2002 21:01'!
next
	| ans |

	ans _ (current degreeSin * magnitude).
	current _ current + step.
	(current >= 360) ifTrue:[
		current _ current \\ 360.
	].
	^ans.! !

!SineWaveGenerator methodsFor: 'accessing' stamp: 'tf 7/25/2002 21:28'!
oneCycle

	^360.0 / step.! !

!SineWaveGenerator methodsFor: 'accessing' stamp: 'tf 7/25/2002 22:17'!
reset
	current _ initialPhase.! !

!SineWaveGenerator methodsFor: 'accessing' stamp: 'tf 7/25/2002 21:28'!
step

	^step.! !


!SineWaveGenerator methodsFor: 'testing' stamp: 'tf 7/25/2002 22:22'!
showOnDisplay
	| xOrigin yOrigin y |

	xOrigin _ 30.
	yOrigin _ 130.

	self reset.

	Display fillBlack: (xOrigin@(yOrigin - 100) extent: 1@100).
	xOrigin to:(xOrigin + 200) do:[ :x |
		y _ (self next * 100.0) + yOrigin.
		Display fillBlack: ((x - 1)@(y - 1) extent: 2@2).
		Display fillBlack: (x@yOrigin extent: 1@1).
		x _ x + 1
	].
! !

"-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- "!

SineWaveGenerator class
	instanceVariableNames: ''!


!SineWaveGenerator class methodsFor: 'examples' stamp: 'tf 7/25/2002 21:30'!
example1
	| tmp |

	tmp _ self new initialize.
	tmp oneCycle:20.
	22 timesRepeat:[
		Transcript show:(tmp next printString); cr.
	].
! !

!SineWaveGenerator class methodsFor: 'examples' stamp: 'tf 7/25/2002 22:22'!
example2

((SineWaveGenerator new initialize magnitude:1.0) oneCycle:100.0) showOnDisplay.
! !