Transition timing bug.

src/slide/s4_automata.rs

@@ -217,11 +217,17 @@ impl Slide for Automata {
                             "Cells with more than three neighbors die",
                             "Cells with three neighbors become alive",
                         ];
-                        for (rule, fade_start) in rules.into_iter().zip(rules_fade) {
+                        for (i, (rule, fade_start)) in rules.into_iter().zip(rules_fade).enumerate()
+                        {
                             // Infinity is a kludge to make it invisible by still take up space.
-                            fade_in(ui, fade_start.unwrap_or(f64::INFINITY), |ui| {
-                                ui.label(format!(" ⏵ {}", rule));
-                            });
+                            fade_in(
+                                ui,
+                                fade_start.unwrap_or(f64::INFINITY)
+                                    + if i == 0 { RULES_DELAY } else { 0.0 },
+                                |ui| {
+                                    ui.label(format!(" ⏵ {}", rule));
+                                },
+                            );
                         }
                     });
             });