Smoother transitions between UDP and animation

- stop() animation before changing state and wait for completion
- additionally fade to black (in case animation does not stop at black
  or when UDP stream ends)
- reset() the animation when changing back to the animation state

include/Animation/AnimationController.h

@@ -24,6 +24,7 @@ class AnimationController
 
         void loop(void);
 
+        void stop(void);
         void restart(void);
 
         bool isIdle(void)

src/Animation/AnimationController.cpp

@@ -64,6 +64,11 @@ void AnimationController::loop(void)
     xSemaphoreGive(m_updateMutex);
 }
 
+void AnimationController::stop(void)
+{
+    m_animation->stop();
+}
+
 void AnimationController::restart(void)
 {
     m_animation->reset();

src/Animation/FireAnimation.cpp

@@ -180,4 +180,8 @@ void FireAnimation::reset(void)
     m_running = true;
 
     m_fader->set_fadestep(10);
+
+    for(auto &energy: m_energy) {
+        energy = 0;
+    }
 }

src/main.cpp

@@ -90,7 +90,8 @@ bool initLEDs()
 enum LEDState {
   UDP,
   ANIMATION,
-  TRANSITION
+  TRANSITION,
+  TRANSITION_FADE2BLACK
 };
 
 static void ledFSM(void)
@@ -135,16 +136,30 @@ static void ledFSM(void)
 
       if(udpProto.loop()) {
         lastUDPUpdate = millis();
-        ledFader.update();
       } else if(millis() - lastUDPUpdate > 3000) {
         // seems like no more UDP data arrives -> transition to ANIMATION state
         nextState = ANIMATION;
         ledState = TRANSITION;
       }
+
+      ledFader.update();
       break;
 
     case TRANSITION:
-      Serial.print("T");
+      Serial.print("S");
+      if(stateEntered) {
+        animController.stop();
+      }
+
+      if(animController.isIdle()) {
+        ledState = TRANSITION_FADE2BLACK;
+      } else {
+        animController.loop();
+      }
+      break;
+
+    case TRANSITION_FADE2BLACK:
+      Serial.print("F");
       if(stateEntered) {
         ledFader.set_fadestep(2);
         ledFader.fade_color(Fader::Color{0, 0, 0, 0});