Implement Animation-specific fadeout

include/Animation/Animation.h

@@ -8,11 +8,45 @@ class Animation
 {
     public:
         Animation(Fader *fader)
-            : m_fader(fader)
+            : m_fader(fader), m_running(true)
         {}
 
+        /*!
+         * The animation's main function. Will be called once per frame.
+         * 
+         * \param frame     The current frame since the animation's start.
+         */
         virtual void loop(uint64_t frame) = 0;
 
+        /*!
+         * Stop the animation. After this function is called, the animation code
+         * might start some transition to black (all LEDs off).
+         */
+        virtual void stop(void)
+        {
+            m_running = false;
+        }
+
+        /*!
+         * A function for checking wether the animation has stopped. This must
+         * return true after the stop transition has finished.
+         * 
+         * \returns True if all activity of the animation code has stopped.
+         */
+        virtual bool finished(void)
+        {
+            return !m_running;
+        }
+
+        /*!
+         * Reset function of the animation code. This should clear any
+         * internal state.
+         * 
+         * By default does nothing.
+         */
+        virtual void reset(void) {};
+
     protected:
         Fader *m_fader;
+        bool m_running;
 };

include/Animation/AnimationController.h

@@ -9,13 +9,15 @@ class AnimationController
     public:
         AnimationController(Fader *fader);
 
-        void setAnimation(std::unique_ptr<Animation> anim, bool transition = true);
+        void changeAnimation(std::unique_ptr<Animation> anim, bool transition = true);
         void loop(void);
 
+        void restart(void);
+
     private:
         Fader *m_fader;
         std::unique_ptr<Animation> m_animation;
+        std::unique_ptr<Animation> m_nextAnimation;
 
-        uint32_t m_transitionTime;
         uint64_t m_frame;
 };

include/Animation/ConnectingAnimation.h

@@ -9,6 +9,17 @@ class ConnectingAnimation : public Animation
 
         void loop(uint64_t frame) override;
 
+        void stop(void) override
+        {
+            m_stopping = true;
+        }
+
+        void reset(void) override
+        {
+            m_stopping = false;
+            m_running = true;
+        }
+
     private:
-        uint32_t m_loop;
+        bool m_stopping;
 };

src/Animation/AnimationController.cpp

@@ -1,30 +1,43 @@
+#include <Arduino.h>
+
 #include "Animation/AnimationController.h"
 
 AnimationController::AnimationController(Fader *fader)
-    : m_fader(fader), m_transitionTime(0), m_frame(0)
+    : m_fader(fader), m_animation(nullptr), m_frame(0)
 {}
 
-void AnimationController::setAnimation(std::unique_ptr<Animation> anim, bool transition)
+void AnimationController::changeAnimation(std::unique_ptr<Animation> anim, bool transition)
 {
-    m_frame = 0;
+    if(transition && m_animation) {
+        m_nextAnimation = std::move(anim);
+        m_animation->stop();
+    } else {
+        m_frame = 0;
 
-    m_animation = std::move(anim);
-
-    if(transition) {
-        m_transitionTime = 256/8;
-
-        m_fader->set_fadestep(8);
-        m_fader->fade_color(Fader::Color{0, 0, 0, 0});
+        m_animation = std::move(anim);
+        m_nextAnimation.reset(nullptr);
     }
 }
 
 void AnimationController::loop(void)
 {
-    if(m_transitionTime > 0) {
-        m_transitionTime--;
-    } else if(m_animation) {
+    if(m_animation && !m_animation->finished()) {
         m_animation->loop(m_frame);
     }
 
+    if(m_nextAnimation &&
+        (!m_animation || m_animation->finished())) {
+        // old animation has finished or is unset -> start the new one
+        m_frame = 0;
+        m_animation.swap(m_nextAnimation);
+        m_nextAnimation.reset(nullptr);
+    }
+
     m_frame++;
 }
+
+void AnimationController::restart(void)
+{
+    m_animation->reset();
+    m_frame = 0;
+}

src/Animation/ConnectingAnimation.cpp

@@ -3,24 +3,30 @@
 #include "Animation/ConnectingAnimation.h"
 
 ConnectingAnimation::ConnectingAnimation(Fader *fader)
-    : Animation(fader)
+    : Animation(fader), m_stopping(false)
 {}
 
 void ConnectingAnimation::loop(uint64_t frame)
 {
     std::size_t nled = m_fader->modules_per_strip();
     std::size_t nstrip = m_fader->strips();
+    uint8_t intensity = 0;
 
     if(frame == 0) {
         m_fader->fade_color(Fader::Color{0, 0, 0, 0});
     }
 
     for(std::size_t strip = 0; strip < nstrip; strip++) {
-        uint8_t intensity = (fasttrigon::fastsin(1 * frame * fasttrigon::LUT_SIZE / 60) + 127) / 4;
+        intensity = (fasttrigon::fastsin(1 * frame * fasttrigon::LUT_SIZE / 60) + 127) / 4;
 
         Fader::Color c;
         c.b = intensity;
 
         m_fader->set_color(strip, 0, c);
     }
+
+    // stop the animation if everything is dark
+    if(m_stopping && intensity == 0) {
+        m_running = false;
+    }
 }

src/main.cpp

@@ -209,7 +209,8 @@ void setup()
   Serial.println();
   Serial.println();
 
-  animController.setAnimation(std::unique_ptr<Animation>(new ConnectingAnimation(&ledFader)));
+  ledFader.set_color(Fader::Color{0, 1, 0, 0});
+  animController.changeAnimation(std::unique_ptr<Animation>(new ConnectingAnimation(&ledFader)));
 
   xTaskCreate(
       ledTask,           /* Task function. */