From 891194ed2e55e243dcc4289c46711bf890f5e5e0 Mon Sep 17 00:00:00 2001
From: tosh <tosh@monster.hlan>
Date: Wed, 27 Mar 2013 17:05:23 +0100
Subject: [PATCH] adds meridians with color gradient and an equator

---
 interface/resources/gen_stars.py | 36 +++++++++++++++++++++++++-------
 1 file changed, 29 insertions(+), 7 deletions(-)

diff --git a/interface/resources/gen_stars.py b/interface/resources/gen_stars.py
index ea8ec92526..b81f54541d 100644
--- a/interface/resources/gen_stars.py
+++ b/interface/resources/gen_stars.py
@@ -12,16 +12,38 @@ from random import random,randint
 from math import sqrt, hypot, atan2, pi, fmod, degrees
 from sys import argv,stderr
 
+hemisphere_only, equator, meridians= False, 1000, 1000
 
-n = 10
+n_random = 100000
 if len(argv) > 1:
-    n = int(argv[1])
-
-hemisphere=False
+    n_random = int(argv[1])
 
 bars_total, bars_prev = 77, 0
 
-for i in range(n):
+def meridian(azimuth,n,(r0,g0,b0),(r1,g1,b1)):
+    alts = 180.0/n
+    for alti in range(n):
+        # color 
+        altj = n-alti-1
+        r = (r0 *altj+alti* r1)/n
+        g = (g0 *altj+alti* g1)/n
+        b = (b0 *altj+alti* b1)/n
+        # position
+        altitude = alts*alti
+        print "%f %f #%02x%02x%02x" % (azimuth,altitude,r,g,b)
+        print "%f %f #%02x%02x%02x" % (azimuth,-altitude,r,g,b)
+
+if meridians:
+    meridian(.2,meridians,(255,255,255), (180, 60,255)) # N->S
+    meridian(90,meridians,( 80,255, 80), (255,240, 40)) # E->W
+
+if equator:
+    azis = 360.0/equator
+    for azii in range(equator):
+        azimuth = azis*azii
+        print "%f %f #%02x%02x%02x" % (azimuth,0,255,255,255)
+
+for i in range(n_random):
     # color
     w = randint(30,randint(40,255))
     r = max(0,min(255,w + randint(-10,70)))
@@ -29,7 +51,7 @@ for i in range(n):
     b = max(0,min(255,w + randint(-10,100)))
     # position
     x,y,z = random()*2-1,random(),random()*2-1
-    if not hemisphere:
+    if not hemisphere_only:
         y = y*2-1
     l = sqrt(x*x + y*y + z*z)
     x /= l; y /= l; z /= l
@@ -38,7 +60,7 @@ for i in range(n):
     azimuth = degrees(fmod(atan2(x,z)+pi,2*pi))
     altitude = degrees(atan2(y,xz))
 
-    bars = round(bars_total*i/n)
+    bars = round(bars_total*i/n_random)
     if bars != bars_prev:
         bars_prev = bars
         bars = int(bars)