update last board, new rules

src/modules/automata.js

@@ -91,6 +91,28 @@ function conwayRules(cell, neighbors) {
   return cell;
 }
 
+// variation on the game of life's rules,
+// where the "three live neighbors" rule is ignored
+function threebornRules(cell, neighbors) {
+  // loneliness rule
+  if (cell === 1 && neighbors < 2) return 0;
+  // overpopulation rule
+  if (cell === 1 && neighbors > 3) return 0;
+  // born when three live neighbors rule
+  return cell;
+}
+
+// variation on the game of life's rules,
+// where the loneliness rule is ignored
+function lonelinessRules(cell, neighbors) {
+  // overpopulation rule
+  if (cell === 1 && neighbors > 3) return 0;
+  // born when three live neighbors rule
+  if (cell === 0 && neighbors === 3) return 1;
+  // the cell remains the same if none apply
+  return cell;
+}
+
 // variation on the game of life's rules,
 // where the overpopulation rule is ignored
 function overpopulationRules(cell, neighbors) {
@@ -160,6 +182,8 @@ export {
   create1dStateOneCell,
   conwayRules,
   overpopulationRules,
+  lonelinessRules,
+  threebornRules,
   evolve1d,
   evolve2d,
 };

src/modules/preset.js

@@ -104,6 +104,18 @@ const preset2dRules = [
     description:
       "Variation on Conway's Game of Life *without* the overpopulation rule",
   },
+  {
+    id: "loneliness",
+    name: "Loneliness variation",
+    description:
+      "Variation on Conway's Game of Life *without* the loneliness rule",
+  },
+  {
+    id: "threeborn",
+    name: "Three lives variation",
+    description:
+      "Variation on Conway's Game of Life *without* the 'three live neighbors' rule",
+  },
 ];
 
 export { presetRuleset, initialStates, preset2dRules };