argparse

waves.py

@@ -2,97 +2,79 @@
 
 import cairo
 import math
-import datetime
+from datetime import datetime
 import calendar
 import random
-from utils import random_color
+import colorsys
+import argparse
 
 
-# dimensions of the output image
-WIDTH, HEIGHT = 1920, 1080
-# how much should the phases be offset?
-WAVE_OFFSET = math.pi / random.choice([1, 2, 4]) #-1.9 
-# amplitude of the sine wave
-#AMPLITUDE = 9
-# only 1 color with shades?
-MONOCHROME = True
-# works only if monochrome is set - uses todays date as base for the color
-DATE_BASED_COLOR = True
-DATE_BASED_AMPLITUDE = True
-DATE_BASED_COUNT = True
-# background black? White otherwise:
-DARK_BG = True
 # precision of the calculation
 PRECISION = 10000
 
-def days_color(date):
-    import colorsys
+
+def get_color_from_date(date: datetime) -> tuple[float, float, float]:
+    """Return a color based on the progress through the year."""
     # a day between 1 and 365 (inclusive)
     today = date.timetuple().tm_yday
-    year = date.year
-    days_in_year = 365 + calendar.isleap(year)
+    days_in_year = 365 + calendar.isleap(date.year)
     # between 0 and 1, how far through the year are we?
-    progress = today/days_in_year
+    progress = today / days_in_year
     return colorsys.hsv_to_rgb(progress, 1, 0.9)
 
-def days_amp(date, waves):
-    day = date.day
+
+def get_amplitude_from_date(date: datetime, waves) -> float:
+    """Return the amplitude of waves, based on progress through the month."""
     days_in_month = calendar.monthrange(date.year, date.month)[1]
-    max_amp = 1/waves/2
-    return day/days_in_month * max_amp
+    max_amp = 1 / waves / 2
+    return date.day / days_in_month * max_amp
 
-def days_count(date):
-    return date.month
 
-def create_wpotd(output):
-    surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, WIDTH, HEIGHT)
+def create_wpotd(
+    width: int,
+    height: int,
+    frequency: int,
+    wave_offset: float,
+    date: datetime = datetime.now(),
+    dark: bool = True,
+) -> cairo.ImageSurface:
+    surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, width, height)
     ctx = cairo.Context(surface)
 
-    ctx.scale(WIDTH, HEIGHT)  # Normalizing the canvas
-    #ctx.set_antialias(cairo.Antialias.BEST)
+    ctx.scale(width, height)  # Normalizing the canvas
+    # ctx.set_antialias(cairo.Antialias.BEST)
 
-    step_size = 1/PRECISION
-    lastpoints = [(x/PRECISION, 0) for x in range(PRECISION+1)]
+    lastpoints = [(x / PRECISION, 0) for x in range(PRECISION + 1)]
 
-    #date = datetime.datetime.strptime('2021-06-30', '%Y-%m-%d')
-    date = datetime.datetime.today()
-    frequency = random.randint(10, 40)
-    if DATE_BASED_COUNT:
-        waves = days_count(date)
-    else:
-        waves = 12
-    if DATE_BASED_AMPLITUDE:
-        amplitude = days_amp(date, waves)
-    else:
-        amplitude = 25
-    
-    if MONOCHROME:
-        if DATE_BASED_COLOR:
-            r, g, b = days_color(date) #datetime.datetime.now())
-        else:
-            r, g, b = random_color()
-        alpha_step = 1/waves
-    if DARK_BG:
-        # make bg black
-        ctx.rectangle(0, 0, 1, 1)
+    waves = date.month
+    amplitude = get_amplitude_from_date(date, waves)
+
+    r, g, b = get_color_from_date(date)
+    alpha_step = 1 / waves
+
+    # background color
+    if dark:
         ctx.set_source_rgb(0, 0, 0)
-        ctx.fill()
+    else:
+        ctx.set_source_rgb(255, 255, 255)
+    ctx.rectangle(0, 0, 1, 1)
+    ctx.fill()
 
-    wave_height = 1/waves
-    for num in range(waves+1):
-        if not MONOCHROME:
-            r, g, b = random_color()
+    wave_height = 1 / waves
+    step_size = 1 / PRECISION
+
+    for wave_index in range(waves + 1):
         points = []
         x = 0
         while x < 1:
-            y = amplitude * math.sin(frequency * x + (num * WAVE_OFFSET) ) 
-            points.append((x, ( y + (0.5+num)*wave_height)))
+            # step along, create points along the wave
+            y = amplitude * math.sin(frequency * x + (wave_index * wave_offset))
+            points.append((x, (y + (0.5 + wave_index) * wave_height)))
             x += step_size
-        #print(f'Draw {len(points)} points for curve {num}')
-        if not MONOCHROME:
-            ctx.set_source_rgb(r, g, b)
+        # print(f'Draw {len(points)} points for curve {num}')
         else:
-            ctx.set_source_rgba(r, g, b, 1 - (alpha_step * num)) # make more transparent toward bottom
+            # make more transparent toward bottom
+            ctx.set_source_rgba(r, g, b, 1 - (alpha_step * wave_index))
         # draw waves
         ctx.move_to(*points[0])
         for p in points[1:]:
@@ -104,11 +86,45 @@ def create_wpotd(output):
         ctx.line_to(*points[0])
         ctx.fill()
         lastpoints = points
-    #return surface
-    surface.write_to_png(output)  # Output to PNG
+    return surface
+
 
 def main():
-    create_wpotd('out/waves.png')
+    parser = argparse.ArgumentParser()
+    parser.add_argument("width", type=int, help="Width of the image")
+    parser.add_argument("height", type=int, help="Height of the image")
+    parser
+    parser.add_argument("--dark", help="Draw on dark background", action="store_true")
+    parser.add_argument(
+        "-o",
+        "--offset",
+        type=float,
+        help="How much the waves should be offset to each other",
+    )
+    parser.add_argument("-f", "--frequency", type=int, help="Frequency of the waves")
+    parser.add_argument(
+        "--stdout", help="Write output image to stdout", action="store_true"
+    )
+    args = parser.parse_args()
+    print(args)
+    if not args.offset:
+        args.offset = math.pi / random.choice([1, 2, 4])
+    if not args.frequency:
+        args.frequency = random.randint(10, 40)
+    output = create_wpotd(
+        args.width,
+        args.height,
+        dark=args.dark,
+        wave_offset=args.offset,
+        frequency=args.frequency,
+    )
+    if args.stdout:
+        import sys
 
-if __name__ == '__main__':
+        output.write_to_png(sys.stdout.buffer)
+    else:
+        output.write_to_png("out/waves.png")
+
+
+if __name__ == "__main__":
     main()