GFX: Belousov–Zhabotinsky reaction as cellular automaton (#157)

* gfx_belou_zhabo_ca

* add belou_zhabo_ca to makefile

GNUmakefile

@@ -15,7 +15,7 @@ GFXMODS_AVAILABLE += gfx_no13 gfx_candyswarm gfx_ursuppe2 gfx_rule90
 GFXMODS_AVAILABLE += gfx_maze gfx_invfourier gfx_colorwheel gfx_snek
 GFXMODS_AVAILABLE += gfx_autoterminal gfx_wator gfx_noisewarp gfx_test
 GFXMODS_AVAILABLE += gfx_multicell gfx_pheromones
-GFXMODS_AVAILABLE += gfx_attractor
+GFXMODS_AVAILABLE += gfx_attractor gfx_belou_zhabo_ca
 GFXMODS_AVAILABLE += gfx_lorenz gfx_pickover gfx_voronoi
 
 BGMMODS_AVAILABLE += bgm_fish bgm_opc bgm_xyscope bgm_pixelflut
@@ -37,7 +37,7 @@ GFXMODS_DEFAULT += gfx_ghostery gfx_ursuppe gfx_afterglow gfx_fire
 GFXMODS_DEFAULT += gfx_candyswarm gfx_ursuppe2 gfx_invfourier gfx_colorwheel
 GFXMODS_DEFAULT += gfx_snek gfx_wator gfx_noisewarp
 GFXMODS_DEFAULT += gfx_multicell gfx_pheromones
-GFXMODS_DEFAULT += gfx_attractor
+GFXMODS_DEFAULT += gfx_attractor gfx_belou_zhabo_ca
 GFXMODS_DEFAULT += gfx_lorenz gfx_pickover gfx_voronoi gfx_voronoi2
 
 BGMMODS_DEFAULT += bgm_fish bgm_pixelflut

src/modules/gfx_belou_zhabo_ca.c

@@ -0,0 +1,144 @@
+#include <math.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <types.h>
+#include <matrix.h>
+#include <timers.h>
+
+#define FPS 18
+#define FRAMETIME (T_SECOND / FPS)
+#define FRAMES (1.5 * TIME_LONG * FPS)
+
+#define  V     12
+#define  G      3
+#define  SEEDS  6
+
+static RGB cols[V + 1];
+
+static uint8_t *cdat;
+uint8_t *ndat;
+
+static int screenW;
+static int screenH;
+
+int urand(int max)
+{
+   return rand() % max;
+}
+
+void sim(void)
+{
+   for (int y = 0; y < screenH; y++)
+   {
+      for (int x = 0; x < screenW; x++)
+      {
+         int sum = 0;
+         int ill = 0;
+         int infected = 0;
+         int self = cdat[y * screenW + x];
+         for (int dy = -1; dy <= 1; dy++)
+         {
+            for (int dx = -1; dx <= 1; dx++)
+            {
+               if (dx == 0 && dy == 0) continue;
+               int mx = (x + dx + screenW) % screenW;
+               int my = (y + dy + screenH) % screenH;
+               int n = cdat[my * screenW + mx];
+               sum += n;
+               if (n >= V) ill++;
+               else if (n > 0) infected++;
+            }
+         }
+         if (self >= V)
+         {
+            ndat[y * screenW + x] = 0;
+         }
+         else if (self > 0)
+         {
+            ndat[y * screenW + x] = MIN(sum / 8 + G, V);
+         }
+         else
+         {
+            ndat[y * screenW + x] = infected + ill;
+         }
+      }
+   }
+
+   uint8_t *tmp = ndat;
+   ndat = cdat;
+   cdat = tmp;
+}
+
+int init(int moduleid, char* argstr)
+{
+   screenW = matrix_getx();
+   screenH = matrix_gety();
+   return 0;
+}
+
+void reset(int moduleid)
+{
+   if (cdat) free(cdat);
+   if (ndat) free(ndat);
+
+   cdat = malloc(screenH * screenW);
+   ndat = malloc(screenH * screenW);
+
+   memset(cdat, 0, screenH * screenW);
+
+   for (int i = 0; i < SEEDS; i++)
+   {
+      int y = urand(screenH);
+      int x = urand(screenW);
+      cdat[y * screenW + x] = 1;
+   }
+
+   int scheme = urand(6);
+   for (int i = 0; i <= V; i++)
+   {
+      double d = (double)i / (V + 2);
+      uint8_t a = 255 * pow(d, 6.0);
+      uint8_t b = 255 * pow(d, 2.5);
+      uint8_t c = 255 * pow(d, 1.0);
+      switch(scheme)
+      {
+         case 0: cols[i] = RGB(a, b, c); break;
+         case 1: cols[i] = RGB(a, c, b); break;
+         case 2: cols[i] = RGB(b, a, c); break;
+         case 3: cols[i] = RGB(b, c, a); break;
+         case 4: cols[i] = RGB(c, a, b); break;
+         case 5: cols[i] = RGB(c, b, a); break;
+      }
+   }
+}
+
+int draw(int moduleid, int argc, char* argv[])
+{  
+  static int frame = 0;
+  oscore_time now = udate();
+
+  sim();
+  for (int y = 0; y < screenH; y++)
+  {
+    for (int x = 0; x < screenW; x++)
+    {
+      matrix_set(x, y, cols[cdat[y * screenW + x]]);
+    }
+  }
+  matrix_render();
+
+  if (frame++ >= FRAMES)
+  {
+    frame = 0;
+    return 1;
+  }
+  oscore_time nexttick = now + T_SECOND / FPS;
+  timer_add(nexttick, moduleid, 0, NULL);
+  return 0;
+}
+
+void deinit(int moduleid)
+{
+}