Reset iterations when reloading config

 - Reset the iterations being rendered when loading a new config. It was
   kind of ridiculous to render a potentially unknown config at whatever
   the previous number of iterations was.

 - Added a quick script that generates a random l-system config. Mostly
   just looks like a twisted strand of hair, but that doesn't mean it
   isn't interesting.

generate_l_system.rb

@@ -0,0 +1,107 @@
+symbols = ['S']
+
+# Generates a replacement rule. Returns ["rule string", [new used_symbols]]
+def random_replacement_rule(all_symbols, used_symbols, rule_symbols)
+  # We can't redefine rule symbols.
+  return ["", used_symbols, rule_symbols] if used_symbols.length == rule_symbols.length
+  start = used_symbols.sample()
+  start = used_symbols.sample() while rule_symbols.include?(start)
+  rule_symbols << start
+  replacement_size = [2, 3, 3, 3, 4, 5].sample()
+  replacement = ""
+  replacement_size.times do
+    # Only choose a new symbol 1/3rd of the time. (Tehcnically less, since all
+    # symbols will include the used ones.
+    if (used_symbols.length < 3) || (rand() < 0.3)
+      symbol = all_symbols.sample()
+      used_symbols << symbol if !used_symbols.include?(symbol)
+    else
+      symbol = used_symbols.sample()
+    end
+    if rand() < 0.01
+      # 1% of the time do a push & pop
+      replacement += "(" + symbol + ")"
+    else
+      replacement += symbol
+    end
+  end
+  rule_string = start + " " + replacement
+  [rule_string, used_symbols, rule_symbols]
+end
+
+def get_move_action()
+  "move_forward %.03f" % [rand()]
+end
+
+def get_rotate_action()
+  action = ["rotate", "pitch", "roll"].sample()
+  angle = 180.0 - (360.0 * rand())
+  "%s %.03f" % [action, angle]
+end
+
+def get_setcolor_action()
+  channel = ["r", "g", "b"].sample()
+  "set_color_%s %.03f" % [channel, rand()]
+end
+
+# Returns an array of random action strings, NOT including push and pop.
+def generate_random_actions()
+  moves = ["move"] * 6
+  rotates = ["rotate"] * 4
+  set_colors = ["set_color"] * 2
+  action_types = moves + rotates + set_colors
+  actions_not_move = rotates + set_colors
+  to_return = []
+  action_count = rand(8)
+  prev_was_move = false
+  action_count.times do
+    if prev_was_move
+      action_type = actions_not_move.sample()
+    else
+      action_type = action_types.sample()
+    end
+    prev_was_move = false
+    if action_type == "move"
+      prev_was_move = true
+      to_return << get_move_action()
+    elsif action_type == "rotate"
+      to_return << get_rotate_action()
+    elsif action_type == "set_color"
+      to_return << get_setcolor_action()
+    end
+  end
+  to_return
+end
+
+# Don't include the start symbol in all_symbols
+all_symbols = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".chars
+used_symbols = ["S"]
+rule_symbols = []
+puts "init S"
+10.times do
+  tmp = random_replacement_rule(all_symbols, used_symbols, rule_symbols)
+  puts tmp[0]
+  used_symbols = tmp[1]
+  rule_symbols = tmp[2]
+end
+
+puts "\nactions
+(
+push_color 0.0
+push_position 0.0
+
+)
+pop_color 0.0
+pop_position 0.0
+
+"
+
+used_symbols.each do |s|
+  # Only generate actions for about 1/3rd of the symbols
+  next if rand() < 0.3
+  puts "#{s}"
+  actions = generate_random_actions()
+  actions.each {|a| puts a}
+  puts ""
+end
+

l_system_3d.c

@@ -184,6 +184,19 @@ static int IncreaseIterations(ApplicationState *s) {
   return 1;
 }
 
+// Sets the current number of iterations to 0. Used after reloading the config.
+static int SetIterationsTo0(ApplicationState *s) {
+  free(s->l_system_string);
+  s->l_system_string = (uint8_t *) strdup(s->config->init);
+  if (!s->l_system_string) {
+    printf("Failed copying the initial L-system string.\n");
+    return 0;
+  }
+  s->l_system_length = strlen(s->config->init);
+  s->l_system_iterations = 0;
+  return 1;
+}
+
 // Reduces the L-system iterations by one. Unfortunately, this is implemented
 // by recomputing the entire thing. Does nothing if we're already at 0
 // iterations.
@@ -194,14 +207,7 @@ static int DecreaseIterations(ApplicationState *s) {
     return 1;
   }
   target_iterations = s->l_system_iterations - 1;
-  free(s->l_system_string);
-  s->l_system_string = (uint8_t *) strdup(s->config->init);
-  if (!s->l_system_string) {
-    printf("Failed copying the initial L-system string.\n");
-    return 0;
-  }
-  s->l_system_length = strlen(s->config->init);
-  s->l_system_iterations = 0;
+  if (!SetIterationsTo0(s)) return 0;
   for (i = 0; i < target_iterations; i++) {
     if (!IncreaseIterations(s)) return 0;
   }
@@ -222,6 +228,10 @@ static void ReloadConfig(ApplicationState *s) {
   s->config = new_config;
   DestroyLSystemConfig(old_config);
   printf("Config %s updated OK.\n", s->config_file_path);
+  if (!(SetIterationsTo0(s) && GenerateVertices(s))) {
+    printf("Failed re-generating image.\n");
+    exit(1);
+  }
 }
 
 static void PrintMemoryUsage(ApplicationState *s) {