X-Git-Url: http://git.veekun.com/zzz-spline-users.git/blobdiff_plain/d35134c7784acce4172ed7bc8800e2fe866d084c..29c938f83a6f65a3f11cc64f39c827b6ab839cf3:/spline/plugins/users/model/__init__.py

diff --git a/spline/plugins/users/model/__init__.py b/spline/plugins/users/model/__init__.py
index e4b824c..2fd444b 100644
--- a/spline/plugins/users/model/__init__.py
+++ b/spline/plugins/users/model/__init__.py
@@ -1,4 +1,6 @@
+# encoding: utf8
 import colorsys
+from math import sin, pi
 import random
 
 from sqlalchemy import Column, ForeignKey
@@ -27,7 +29,6 @@ class User(TableBase):
         """Returns a list of (width, '#rrggbb') tuples that semi-uniquely
         identify this user.
         """
-
         width_blob, colors_blob = self.unique_identifier[0:8], \
                                   self.unique_identifier[8:32]
 
@@ -38,17 +39,43 @@ class User(TableBase):
         total_width = sum(widths)
 
         ret = []
+        last_hue = None
         for i in range(4):
-            h = int(colors_blob[i*6:i*6+2], 16) / 256.0
+            raw_hue = int(colors_blob[i*6:i*6+2], 16) / 256.0
+            if last_hue:
+                # Make adjacent hues relatively close together, to avoid green
+                # + purple sorts of clashes.
+                # Minimum distance is 0.1; maximum is 0.35.  Leaves half the
+                # spectrum available for any given color.
+                # Change 0.0–0.1 to -0.35–-0.1, 0.1–0.35
+                hue_offset = raw_hue * 0.5 - 0.25
+                if raw_hue < 0:
+                    raw_hue -= 0.1
+                else:
+                    raw_hue += 0.1
+
+                h = last_hue + raw_hue
+            else:
+                h = raw_hue
+            last_hue = h
+
             l = int(colors_blob[i*6+2:i*6+4], 16) / 256.0
             s = int(colors_blob[i*6+4:i*6+6], 16) / 256.0
 
-            # Cap lightness to 0.25 to 0.75, so it's not too close to white or
+            # Secondary colors are extremely biased against when picking
+            # randomly from the hue spectrum.
+            # To alleviate this, try to bias hue towards secondary colors.
+            # This adjustment is based purely on experimentation; sin() works
+            # well because hue is periodic, * 6 means each period is 1/3 the
+            # hue spectrum, and the final / 24 is eyeballed
+            h += sin(h * pi * 6) / 24
+
+            # Cap lightness to 0.4 to 0.95, so it's not too close to white or
             # black
-            l = l * 0.5 + 0.25
+            l = l * 0.6 + 0.3
 
             # Cap saturation to 0.5 to 1.0, so the color isn't too gray
-            s = s * 0.5 + 0.5
+            s = s * 0.6 + 0.3
 
             r, g, b = colorsys.hls_to_rgb(h, l, s)
             color = "#{0:02x}{1:02x}{2:02x}".format(
@@ -67,4 +94,3 @@ class OpenID(TableBase):
     openid = Column(Unicode(length=255), primary_key=True)
     user_id = Column(Integer, ForeignKey('users.id'))
     user = relation(User, lazy=False, backref='openids')
-