some cleanup and changes

This results in the expected value of the number of mutations at any
one iteration to be 1, which is good.

src/base.h

@@ -36,7 +36,7 @@ typedef double f64;
 // Simulation constants
 #define SIZEOF_PROGRAM_POW_2 6
 #define SIZEOF_PROGRAM       (1 << SIZEOF_PROGRAM_POW_2)
-#define NUM_PROGRAMS_POW_2   10
+#define NUM_PROGRAMS_POW_2   12
 #define NUM_PROGRAMS         (1 << NUM_PROGRAMS_POW_2)
 
 #define SIMULATION_SIZE     (NUM_PROGRAMS * SIZEOF_PROGRAM)
@@ -47,10 +47,9 @@ typedef double f64;
 #define CELL_WIDTH    (WIDTH / (f64)CELL_ROW_SIZE)
 #define CELL_HEIGHT   (HEIGHT / (f64)CELL_ROW_SIZE)
 
-#define MUTATION_CHANCE 5000
-#define MUTATION_OFFSET 1
+#define MUTATION_CHANCE (SIMULATION_SIZE)
 
-#define DRAW_PROGRAM_OUTLINE 1
+#define DRAW_PROGRAM_OUTLINE 0
 
 #endif
 

src/bf.c

@@ -105,10 +105,6 @@ void program_execute(struct ProgramConcat *prg)
     switch (opcode)
     {
     case '<':
-      // NOTE: We're doing a safe subtraction here, but maybe we should
-      // terminate execution if subtraction will overflow?
-      // ctx.head0 = SAFE_SUB(ctx.head0, 1);
-
       ctx.head0 -= 1;
       ctx.head0 %= sizeof(prg->tape);
       ++ctx.ip;
@@ -118,10 +114,6 @@ void program_execute(struct ProgramConcat *prg)
       ++ctx.ip;
       break;
     case '{':
-      // NOTE: We're doing a safe subtraction here, but maybe we should
-      // terminate execution if subtraction will overflow?
-      // ctx.head1 = SAFE_SUB(ctx.head1, 1);
-
       ctx.head1 -= 1;
       ctx.head1 %= sizeof(prg->tape);
       ++ctx.ip;

src/simulation.c

@@ -45,6 +45,7 @@ void simulation_iterate(simulation_t *sim)
   {
     a_b_concat = calloc(1, sizeof(*a_b_concat));
   }
+  // Ensure a_b_concat is completely zeroed
   memset(a_b_concat, 0, sizeof(*a_b_concat));
 
   // Reaction: Concat, execute, split.
@@ -155,7 +156,7 @@ void simulation_pick_rng_neighbour(u64 *a, u64 *b)
   *b = neighbours[rand() % size];
 }
 
-static char *VALID_OPS               = "<>{}-+.,[]";
+static const char *VALID_OPS         = "<>{}-+.,[]";
 static const Color possible_colors[] = {
     ['<'] = {230, 25, 75, 255},  ['>'] = {60, 180, 75, 255},
     ['{'] = {255, 225, 25, 255}, ['}'] = {0, 130, 200, 255},
@@ -167,7 +168,7 @@ static const Color possible_colors[] = {
 
 Color simulation_cell_color(const bf_token cell)
 {
-  return possible_colors[strchr(VALID_OPS, cell) ? cell : '\0'];
+  return possible_colors[(!!strchr(VALID_OPS, (u8)cell)) * cell];
 }
 
 /* Copyright (C) 2026 Aryadev Chavali