visual art: Add a script for user identicons.

generate-avatars/Privisus/README.md

@@ -0,0 +1,35 @@
+# Approach
+
+I decided it would be a good idea to approach this problem 
+mathematically. Boy I was in for a journey.
+
+Then I thought about "periodic" things in math, I figured that a sine, cosine, and tangent would be fine to work with.
+
+I also used PyPNG because it is small and relatively trivial to use and
+understand.
+
+(Note: PyPNG can be obtained via `curl -LO https://raw.github.com/drj11/pypng/master/code/png.py`)
+
+# Process
+
+I tried to experiment a little bit in Demos to see if it has a potential.
+Something like this showed up:
+
+![Desmos plot 1](https://lambda.sx/T2V.png "Desmos plot, first three enabled")
+
+![Desmos plot 2](https://lambda.sx/KS3.png "Desmos plot, last three enabled")
+
+Okay, looks promising, so I applied them into the program with few tweaks
+here and there.
+
+# Results
+
+Results can be checked with the following command:
+
+`avatar-1.png`: `python generate-identicons.py Alice`  
+`avatar-2.png`: `python generate-identicons.py Bob`  
+`avatar-3.png`: `python generate-identicons.py Marry`  
+`avatar-4.png`: `python generate-identicons.py Zulip`  
+`avatar-5.png`: `python generate-identicons.py Privisus 
+[email protected]`  
+

generate-avatars/Privisus/generate-identicons.py

@@ -0,0 +1,140 @@
+'''Generates a unique 50px * 50px .png file from user name
+
+Usage: generate-identicons.py username <useremail>
+
+Keyword arguments:
+    username -- User's username in string
+    useremail (optional) -- User's email
+
+Returns: void
+'''
+
+import sys
+import hashlib
+import png
+from math import sin, cos, tan
+
+#Return the sum of the list with this pattern: + * - //
+def unique_sum(val_list):
+    sum = 0
+    for k, ascii_value in enumerate(val_list):
+        if k % 4 == 0:
+            sum += ascii_value
+        elif k % 4 == 1:
+            sum *= ascii_value
+        elif k % 4 == 2:
+            sum -= ascii_value
+        elif k % 4 == 3:
+            sum //= ascii_value
+
+    return sum
+
+#create sha-1 instance
+sha1 = hashlib.sha1()
+
+#create encoded, utf-8 string from the second argument passed by the user
+username_encoded = sys.argv[1].encode('utf-8')
+
+#check if the user supplied more than or equal to three arguments
+if len(sys.argv) >= 3:
+    #if it does, set the encoded user-email
+    useremail_encoded = sys.argv[2].encode('utf-8')
+else:
+    #if not, use the default encoded user-email
+    useremail_encoded = "DEFAULT".encode('utf-8')
+
+#create sha-1 of username
+sha1.update(username_encoded)
+username_sha1 = sha1.hexdigest()
+
+#create sha-1 of useremail
+sha1.update(useremail_encoded) #dependent on the username
+useremail_sha1 = sha1.hexdigest()
+
+#convert each character in each string to ASCII value, 
+#and summing it with this pattern: + * - //
+
+username_val_list = [ord(character) for character in username_sha1]
+useremail_val_list = [ord(character) for character in useremail_sha1]
+
+username_sum = unique_sum(username_val_list)
+useremail_sum = unique_sum(useremail_val_list)
+
+#figure out the trig values for the half of the icon
+if useremail_sum % 3 == 0:
+    trig_values = [sin((useremail_sum**2+1)*x+useremail_sum) for x in range(0,2500//4)]
+elif useremail_sum % 3 == 1:
+    trig_values = [cos((useremail_sum**2+1)*x+useremail_sum) for x in range(0,2500//4)]
+elif useremail_sum % 3 == 2:
+    trig_values = [tan((useremail_sum**2+1)*x+useremail_sum) for x in range(0,2500//4)]
+
+grid_locations = []
+
+#This can be simplified with list comprehension, but I decided to left it this way for readability
+for trig_value in trig_values:
+    q1 = round(255 * sin(username_sum * (useremail_sum * trig_value)))
+    q2 = round(255 * sin(useremail_sum))
+
+    if q1 == 0:
+        q1 = 1
+
+    if q2 == 0:
+        q2 = 1
+
+    k = round(q1) % round(q2)
+
+    if k >= 25 and k < 100:
+        k = 100
+
+    if k >= 100 and k < 200:
+        k = 200
+
+    if k > 200:
+        k = 100
+
+    grid_locations.append(k)
+
+#check if the list is generally dull, if it is, contrast it
+if sum(grid_locations) < 25*25*100:
+    average_light = 255 * sum(grid_locations) // (25*25*100)
+
+    grid_fix_dull = []
+
+    for color in grid_locations:
+        if color < average_light:
+            grid_fix_dull.append(255-average_light)
+        else:
+            grid_fix_dull.append((color*2) % 256)
+
+    grid_locations = grid_fix_dull
+
+if sum(grid_locations) < 25*25*100:
+    grid_locations = [255-color for color in grid_locations]
+
+#split the list into chunk of 25 ints, which will be mirrored in the next steps
+grid_squared = [grid_locations[x:x+25] for x in range(0, len(grid_locations),25)]
+
+grid_rgb = []
+
+color_decide = (username_sum+useremail_sum) % 3
+
+for row in grid_squared:
+    rgb_row = []
+    for light in row:
+        if color_decide == 0:
+            rgb_row.extend([light, light//2, light//3])
+        elif color_decide == 1:
+            rgb_row.extend([light//2, light , light//3])
+        elif color_decide == 2:
+            rgb_row.extend([light//2, light//3, light])
+    grid_rgb.append(rgb_row)
+
+#for each list, add a mirror list so it is symetrical with the respect to y axis
+grid_rgb = [grid+grid[::-1] for grid in grid_rgb]
+
+#for each list, add a mirror list so it is symetrical with the respect to x axis
+grid_rgb = grid_rgb + grid_rgb[::-1]
+
+#put the image and save it
+png.from_array(grid_rgb, 'RGB').save(sys.argv[1] + ".png")
+