Class: AnimatedWaveDemo
- Defined in:
- sample/demos-en/aniwave.rb,
sample/demos-jp/aniwave.rb
Overview
animated wave
Instance Method Summary collapse
-
#basicMotion ⇒ Object
Basic motion handler.
-
#initialize(frame, dir = :left) ⇒ AnimatedWaveDemo
constructor
A new instance of AnimatedWaveDemo.
-
#move ⇒ Object
animation control.
-
#reverser ⇒ Object
Oscillation handler.
- #stop ⇒ Object
Constructor Details
#initialize(frame, dir = :left) ⇒ AnimatedWaveDemo
Returns a new instance of AnimatedWaveDemo.
48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 |
# File 'sample/demos-en/aniwave.rb', line 48 def initialize(frame, dir=:left) @direction = dir # create canvas widget @c = TkCanvas.new(frame, :width=>300, :height=>200, :background=>'black') @c.pack(:padx=>10, :pady=>10, :expand=>true) # Creates a coordinates list of a wave. @waveCoords = [] @backupCoords = [] n = 0 (-10..300).step(5){|n| @waveCoords << [n, 100]; @backupCoords << [n, 100] } @waveCoords << [n, 0]; @backupCoords << [n, 0] @waveCoords << [n+5, 200]; @backupCoords << [n+5, 200] @coordsLen = @waveCoords.length # Create a smoothed line and arrange for its coordinates to be the # contents of the variable waveCoords. @line = TkcLine.new(@c, @waveCoords, :width=>1, :fill=>'green', :smooth=>true) # Main animation "loop". # Theoretically 100 frames-per-second (==10ms between frames) @timer = TkTimer.new(10){ basicMotion; reverser } # Arrange for the animation loop to stop when the canvas is deleted @c.(TkBindTag.new('Destroy'){ @timer.stop }) end |
Instance Method Details
#basicMotion ⇒ Object
Basic motion handler. Given what direction the wave is travelling in, it advances the y coordinates in the coordinate-list one step in that direction.
81 82 83 84 85 86 87 88 89 90 91 |
# File 'sample/demos-en/aniwave.rb', line 81 def basicMotion @backupCoords, @waveCoords = @waveCoords, @backupCoords (0...@coordsLen).each{|idx| if @direction == :left @waveCoords[idx][1] = @backupCoords[(idx+1 == @coordsLen)? 0: idx+1][1] else @waveCoords[idx][1] = @backupCoords[(idx == 0)? -1: idx-1][1] end } @line.coords(@waveCoords) end |
#move ⇒ Object
animation control
105 106 107 |
# File 'sample/demos-en/aniwave.rb', line 105 def move @timer.start end |
#reverser ⇒ Object
Oscillation handler. This detects whether to reverse the direction of the wave by checking to see if the peak of the wave has moved off the screen (whose size we know already.)
96 97 98 99 100 101 102 |
# File 'sample/demos-en/aniwave.rb', line 96 def reverser if @waveCoords[0][1] < 10 @direction = :right elsif @waveCoords[-1][1] < 10 @direction = :left end end |
#stop ⇒ Object
109 110 111 |
# File 'sample/demos-en/aniwave.rb', line 109 def stop @timer.stop end |