params, offset, dark bg

waves.py

@@ -4,9 +4,19 @@ import cairo
 import math
 from utils import random_color
 
-WIDTH, HEIGHT = 256, 256
-WAVES = 8
 
+# dimensions of the output image
+WIDTH, HEIGHT = 1024, 1024
+# numbers of waves
+WAVES = 10
+# how much should the phases be offset?
+WAVE_OFFSET = -0.7
+# amplitude of the sine wave
+AMPLITUDE = 25
+# only 1 color with shades?
+MONOCHROME = True
+# background black? White otherwise:
+DARK_BG = True
 
 def main():
     
@@ -17,21 +27,34 @@ def main():
 
     wave_height = 1/WAVES
     lastpoints = [(x/1000, 0) for x in range(1000)]
+    if DARK_BG:
+        # make bg black
+        ctx.rectangle(0, 0, 1, 1)
+        ctx.set_source_rgb(0, 0, 0)
+        ctx.fill()
     
-    for num in range(WAVES):
+    if MONOCHROME:
         r, g, b = random_color()
+        alpha_step = 1/WAVES
+
+    for num in range(WAVES+1):
+        if not MONOCHROME:
+            r, g, b = random_color()
         points = []
         x = 0
         while x < 1:
-            y = math.sin(x*50) * 0.1
+            y = math.sin(x*AMPLITUDE + (num * WAVE_OFFSET) ) * 0.1 
             points.append((x, ( (y/4) + ((0.5+num)*wave_height))))
             x += 0.001
+        if not MONOCHROME:
+            ctx.set_source_rgb(r, g, b)
+        else:
+            ctx.set_source_rgba(r, g, b, 1 - (alpha_step * num)) # make more transparent toward bottom
         # draw waves
         ctx.move_to(*points[0])
         for p in points[1:]:
             ctx.line_to(*p)
         ctx.set_line_width(0.002)
-        ctx.set_source_rgb(r, g, b)
         ctx.stroke()
         # fill area above
         for pos in range(len(points)):