Contents

# Sine Wave
# by Daniel Shiffman.  
# 
# Render a simple sine wave. 


def setup    
  size 640, 360    
  frame_rate 30
  color_mode RGB, 255, 255, 255, 100   
  @w = width + 16
  @period = 500.0
  @x_spacing = 8
  @dx = (TWO_PI / @period) * @x_spacing
  @y_values = []
  @theta = 0.0
  @amplitude = 75.0
  
end

def draw    
  background 0
  calc_wave
  draw_wave  	
end

def calc_wave    
  @theta += 0.02  	
  x = @theta
  (0...(@w/@x_spacing)).each do |i|    
    @y_values[i] = sin(x) * @amplitude
    x += @dx
  end  	
end

def draw_wave    
	no_stroke
	fill 255, 50
	ellipse_mode CENTER	
	@y_values.each_with_index do |v, x|  	    
	  ellipse x*@x_spacing, height/2+v, 16, 16
	end  	
end

Version data entries

4 entries across 4 versions & 1 rubygems

Version	Path
ruby-processing-2.4.4	samples/processing_app/basics/math/sine_wave.rb
ruby-processing-2.4.3	samples/processing_app/basics/math/sine_wave.rb
ruby-processing-2.4.2	samples/processing_app/basics/math/sine_wave.rb
ruby-processing-2.4.1	samples/processing_app/basics/math/sine_wave.rb