--- deliantra/server/common/noise.C	2011/04/23 04:46:25	1.4
+++ deliantra/server/common/noise.C	2011/04/23 06:35:55	1.7
@@ -1,7 +1,7 @@
 /*
  * This file is part of Deliantra, the Roguelike Realtime MMORPG.
  * 
- * Copyright (©) 2010 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
+ * Copyright (©) 2010,2011 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
  * 
  * Deliantra is free software: you can redistribute it and/or modify it under
  * the terms of the Affero GNU General Public License as published by the
@@ -25,6 +25,7 @@
 /////////////////////////////////////////////////////////////////////////////
 
 // http://www-wales.ch.cam.ac.uk/~wales/CCD/Thomson/table.html, random permutation
+// used as gradient vectors for noise3d
 static const float charges[256][3] = {
   6.32096444e-01, -6.11406706e-01, 4.76062943e-01, 5.19172442e-01, 8.08229585e-01, -2.77893708e-01,
   -8.81072422e-01, -4.68301230e-01, 6.63727731e-02, -1.92122323e-01, 9.81341519e-01, -7.60505942e-03,
@@ -156,6 +157,25 @@
   -3.07350590e-01, -9.14677987e-01, 2.62487703e-01, 5.60298616e-01, 1.74821302e-01, 8.09631381e-01,
 };
 
+/////////////////////////////////////////////////////////////////////////////
+
+template<int N, typename T>
+template<class random_generator>
+void
+permutation<N,T>::seed (random_generator &rng)
+{
+  for (int i = 0; i < N; ++i)
+    pmap[i] = i;
+
+  // fisher-yates to randomly perturb
+  for (int i = N; --i; )
+    ::swap (pmap[i], pmap[rng (i + 1)]);
+}
+
+template class permutation<256, uint8_t>;
+
+/////////////////////////////////////////////////////////////////////////////
+
 static vec2d
 floor (vec2d v)
 {
@@ -172,7 +192,7 @@
 {
   seedable_rand_gen rng (seed);
 
-#if 1
+#if 0
   for (int i = 0; i < 256; ++i)
     {
       vec2d rv (rng () - 0.5f, rng () - 0.5f);
@@ -187,12 +207,12 @@
     }
 #endif
 
-#if 0
-  float offset = rng () * 3.14159265;
+#if 1
+  float offset = rng () * M_PI;
 
   for (int i = 0; i < 256; ++i)
     {
-      float phi = i * (3.14159265 * 2 / 256) + offset;
+      float phi = i * (M_PI * 2 / 256) + offset;
 
       rvec[i][0] =  sinf (phi);
       rvec[i][1] = -cosf (phi);
@@ -518,13 +538,13 @@
 
 /////////////////////////////////////////////////////////////////////////////
 
-#if 0
-void hack(); void hack()
+void noise_test ();
+void noise_test ()
 {
-  frac_gen<vec2d> gen (0.5, 2);
+  frac_gen<vec2d> gen (0.5, 1.9);
   frac_gen<vec3d> gen3;
 
-#if 0
+#if 1
   int N = 1024;
 
   printf ("P5 %d %d 255\n", N, N);
@@ -537,7 +557,7 @@
         //putc (127 * n.noise (x * 0.1, y * 0.1, 0, 0,0,1) + 128, stdout);
         //putc (256 * gen.terrain2 (x * 0.004, y * 0.004, 8), stdout);
         //putc (256 * gen.fBm (x * 0.01, y * 0.01, 3), stdout);
-        //putc (256 * gen.turbulence (x * 0.004 - 1, y * 0.004 - 1, 8), stdout);
+        putc (256 * gen.turbulence (vec2d (x * 0.004 - 1, y * 0.004 - 1), 8), stdout);
         //putc (256 * gen.heterofractal (x * 0.008, y * 0.008, 8, 0.9), stdout);
 
         // mountais or somesuch(?)
@@ -546,7 +566,9 @@
         // temperature
         //putc (256 * gen.fBm (x * 0.002, y * 0.002, 2), stdout);
         // rain
-        //putc (256 * gen.ridgedmultifractal (x * 0.01, y * 0.01, 3, 1.03, 2), stdout);
+
+        //cells
+        //putc (256 * gen.ridgedmultifractal (vec2d (x * 0.01, y * 0.01), 3, 0.5 + gen.noise(vec2d(x*0.01,y*0.01)), 2), stdout);
       }
     }
 #else
@@ -592,4 +614,3 @@
 
   exit (0);
 }
-#endif