shithub: orca

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Cleanup

--- a/sim.c

+++ b/sim.c

@@ -611,16 +611,6 @@

   }

 END_OPERATOR

-static Usz hash32_shift_mult(Usz key) {

-  Usz c2 = UINT32_C(0x27d4eb2d);

-  key = (key ^ UINT32_C(61)) ^ (key >> UINT32_C(16));

-  key = key + (key << UINT32_C(3));

-  key = key ^ (key >> UINT32_C(4));

-  key = key * c2;

-  key = key ^ (key >> UINT32_C(15));

-  return key;

-}

-

 BEGIN_OPERATOR(random)

   LOWERCASE_REQUIRES_BANG;

   PORT(0, -1, IN | PARAM);

@@ -641,8 +631,16 @@

     min = b;

     max = a;

   }

-  Usz key = hash32_shift_mult((extra_params->random_seed + y * width + x) ^

-                              (Tick_number << UINT32_C(16)));

+  // Initial input params for the hash

+  Usz key = (extra_params->random_seed + y * width + x) ^

+            (Tick_number << UINT32_C(16));

+  // 32-bit shift_mult hash to evenly distribute bits

+  key = (key ^ UINT32_C(61)) ^ (key >> UINT32_C(16));

+  key = key + (key << UINT32_C(3));

+  key = key ^ (key >> UINT32_C(4));

+  key = key * UINT32_C(0x27d4eb2d);

+  key = key ^ (key >> UINT32_C(15));

+  // Hash finished. Restrict to desired range of numbers.

   Usz val = key % (max - min) + min;

   POKE(1, 0, glyph_of(val));

 END_OPERATOR