Modular light transformers (#2124)

esphome/components/light/addressable_light.cpp

@@ -24,6 +24,10 @@ void AddressableLight::call_setup() {
 #endif
 }
 
+std::unique_ptr<LightTransformer> AddressableLight::create_default_transition() {
+  return make_unique<AddressableLightTransformer>(*this);
+}
+
 Color esp_color_from_light_color_values(LightColorValues val) {
   auto r = to_uint8_scale(val.get_color_brightness() * val.get_red());
   auto g = to_uint8_scale(val.get_color_brightness() * val.get_green());
@@ -37,66 +41,67 @@ void AddressableLight::write_state(LightState *state) {
   auto max_brightness = to_uint8_scale(val.get_brightness() * val.get_state());
   this->correction_.set_local_brightness(max_brightness);
 
-  this->last_transition_progress_ = 0.0f;
-  this->accumulated_alpha_ = 0.0f;
-
   if (this->is_effect_active())
     return;
 
   // don't use LightState helper, gamma correction+brightness is handled by ESPColorView
+  this->all() = esp_color_from_light_color_values(val);
+}
 
-  if (state->transformer_ == nullptr || !state->transformer_->is_transition()) {
+void AddressableLightTransformer::start() {
-    // no transformer active or non-transition one
+  auto end_values = this->target_values_;
-    this->all() = esp_color_from_light_color_values(val);
+  this->target_color_ = esp_color_from_light_color_values(end_values);
-  } else {
-    // transition transformer active, activate specialized transition for addressable effects
-    // instead of using a unified transition for all LEDs, we use the current state each LED as the
-    // start. Warning: ugly
 
-    // We can't use a direct lerp smoothing here though - that would require creating a copy of the original
+  // our transition will handle brightness, disable brightness in correction.
-    // state of each LED at the start of the transition
+  this->light_.correction_.set_local_brightness(255);
-    // Instead, we "fake" the look of the LERP by using an exponential average over time and using
+  this->target_color_ *= to_uint8_scale(end_values.get_brightness() * end_values.get_state());
-    // dynamically-calculated alpha values to match the look of the
+}
 
-    float new_progress = state->transformer_->get_progress();
+optional<LightColorValues> AddressableLightTransformer::apply() {
-    float prev_smoothed = LightTransitionTransformer::smoothed_progress(last_transition_progress_);
+  // Don't try to transition over running effects, instead immediately use the target values. write_state() and the
-    float new_smoothed = LightTransitionTransformer::smoothed_progress(new_progress);
+  // effects pick up the change from current_values.
-    this->last_transition_progress_ = new_progress;
+  if (this->light_.is_effect_active())
+    return this->target_values_;
 
-    auto end_values = state->transformer_->get_end_values();
+  // Use a specialized transition for addressable lights: instead of using a unified transition for
-    Color target_color = esp_color_from_light_color_values(end_values);
+  // all LEDs, we use the current state of each LED as the start.
 
-    // our transition will handle brightness, disable brightness in correction.
+  // We can't use a direct lerp smoothing here though - that would require creating a copy of the original
-    this->correction_.set_local_brightness(255);
+  // state of each LED at the start of the transition.
-    target_color *= to_uint8_scale(end_values.get_brightness() * end_values.get_state());
+  // Instead, we "fake" the look of the LERP by using an exponential average over time and using
+  // dynamically-calculated alpha values to match the look.
 
-    float denom = (1.0f - new_smoothed);
+  float smoothed_progress = LightTransitionTransformer::smoothed_progress(this->get_progress_());
-    float alpha = denom == 0.0f ? 0.0f : (new_smoothed - prev_smoothed) / denom;
 
-    // We need to use a low-resolution alpha here which makes the transition set in only after ~half of the length
+  float denom = (1.0f - smoothed_progress);
-    // We solve this by accumulating the fractional part of the alpha over time.
+  float alpha = denom == 0.0f ? 0.0f : (smoothed_progress - this->last_transition_progress_) / denom;
-    float alpha255 = alpha * 255.0f;
-    float alpha255int = floorf(alpha255);
-    float alpha255remainder = alpha255 - alpha255int;
 
-    this->accumulated_alpha_ += alpha255remainder;
+  // We need to use a low-resolution alpha here which makes the transition set in only after ~half of the length
-    float alpha_add = floorf(this->accumulated_alpha_);
+  // We solve this by accumulating the fractional part of the alpha over time.
-    this->accumulated_alpha_ -= alpha_add;
+  float alpha255 = alpha * 255.0f;
+  float alpha255int = floorf(alpha255);
+  float alpha255remainder = alpha255 - alpha255int;
 
-    alpha255 += alpha_add;
+  this->accumulated_alpha_ += alpha255remainder;
-    alpha255 = clamp(alpha255, 0.0f, 255.0f);
+  float alpha_add = floorf(this->accumulated_alpha_);
-    auto alpha8 = static_cast<uint8_t>(alpha255);
+  this->accumulated_alpha_ -= alpha_add;
 
-    if (alpha8 != 0) {
+  alpha255 += alpha_add;
-      uint8_t inv_alpha8 = 255 - alpha8;
+  alpha255 = clamp(alpha255, 0.0f, 255.0f);
-      Color add = target_color * alpha8;
+  auto alpha8 = static_cast<uint8_t>(alpha255);
 
-      for (auto led : *this)
+  if (alpha8 != 0) {
-        led = add + led.get() * inv_alpha8;
+    uint8_t inv_alpha8 = 255 - alpha8;
-    }
+    Color add = this->target_color_ * alpha8;
+
+    for (auto led : this->light_)
+      led.set(add + led.get() * inv_alpha8);
   }
 
-  this->schedule_show();
+  this->last_transition_progress_ = smoothed_progress;
+  this->light_.schedule_show();
+
+  return {};
 }
 
 }  // namespace light

esphome/components/light/addressable_light.h

@@ -8,6 +8,7 @@
 #include "esp_range_view.h"
 #include "light_output.h"
 #include "light_state.h"
+#include "transformers.h"
 
 #ifdef USE_POWER_SUPPLY
 #include "esphome/components/power_supply/power_supply.h"
@@ -53,6 +54,7 @@ class AddressableLight : public LightOutput, public Component {
   bool is_effect_active() const { return this->effect_active_; }
   void set_effect_active(bool effect_active) { this->effect_active_ = effect_active; }
   void write_state(LightState *state) override;
+  std::unique_ptr<LightTransformer> create_default_transition() override;
   void set_correction(float red, float green, float blue, float white = 1.0f) {
     this->correction_.set_max_brightness(
         Color(to_uint8_scale(red), to_uint8_scale(green), to_uint8_scale(blue), to_uint8_scale(white)));
@@ -70,6 +72,8 @@ class AddressableLight : public LightOutput, public Component {
   void call_setup() override;
 
  protected:
+  friend class AddressableLightTransformer;
+
   bool should_show_() const { return this->effect_active_ || this->next_show_; }
   void mark_shown_() {
     this->next_show_ = false;
@@ -92,6 +96,18 @@ class AddressableLight : public LightOutput, public Component {
   power_supply::PowerSupplyRequester power_;
 #endif
   LightState *state_parent_{nullptr};
+};
+
+class AddressableLightTransformer : public LightTransitionTransformer {
+ public:
+  AddressableLightTransformer(AddressableLight &light) : light_(light) {}
+
+  void start() override;
+  optional<LightColorValues> apply() override;
+
+ protected:
+  AddressableLight &light_;
+  Color target_color_{};
   float last_transition_progress_{0.0f};
   float accumulated_alpha_{0.0f};
 };

esphome/components/light/light_output.cpp

@@ -0,0 +1,12 @@
+#include "light_output.h"
+#include "transformers.h"
+
+namespace esphome {
+namespace light {
+
+std::unique_ptr<LightTransformer> LightOutput::create_default_transition() {
+  return make_unique<LightTransitionTransformer>();
+}
+
+}  // namespace light
+}  // namespace esphome

esphome/components/light/light_output.h

@@ -3,6 +3,7 @@
 #include "esphome/core/component.h"
 #include "light_traits.h"
 #include "light_state.h"
+#include "light_transformer.h"
 
 namespace esphome {
 namespace light {
@@ -13,6 +14,9 @@ class LightOutput {
   /// Return the LightTraits of this LightOutput.
   virtual LightTraits get_traits() = 0;
 
+  /// Return the default transformer used for transitions.
+  virtual std::unique_ptr<LightTransformer> create_default_transition();
+
   virtual void setup_state(LightState *state) {}
 
   virtual void write_state(LightState *state) = 0;

esphome/components/light/light_state.cpp

@@ -1,6 +1,7 @@
-#include "light_state.h"
 #include "esphome/core/log.h"
+#include "light_state.h"
 #include "light_output.h"
+#include "transformers.h"
 
 namespace esphome {
 namespace light {
@@ -105,19 +106,19 @@ void LightState::loop() {
 
   // Apply transformer (if any)
   if (this->transformer_ != nullptr) {
+    auto values = this->transformer_->apply();
+    this->next_write_ = values.has_value();  // don't write if transformer doesn't want us to
+    if (values.has_value())
+      this->current_values = *values;
+
     if (this->transformer_->is_finished()) {
-      this->remote_values = this->current_values = this->transformer_->get_end_values();
+      this->transformer_->stop();
-      this->target_state_reached_callback_.call();
-      if (this->transformer_->publish_at_end())
-        this->publish_state();
       this->transformer_ = nullptr;
-    } else {
+      this->target_state_reached_callback_.call();
-      this->current_values = this->transformer_->get_values();
-      this->remote_values = this->transformer_->get_remote_values();
     }
-    this->next_write_ = true;
   }
 
+  // Write state to the light
   if (this->next_write_) {
     this->output_->write_state(this);
     this->next_write_ = false;
@@ -217,18 +218,21 @@ void LightState::stop_effect_() {
 }
 
 void LightState::start_transition_(const LightColorValues &target, uint32_t length) {
-  this->transformer_ = make_unique<LightTransitionTransformer>(millis(), length, this->current_values, target);
+  this->transformer_ = this->output_->create_default_transition();
-  this->remote_values = this->transformer_->get_remote_values();
+  this->transformer_->setup(this->current_values, target, length);
+  this->remote_values = target;
 }
 
 void LightState::start_flash_(const LightColorValues &target, uint32_t length) {
-  LightColorValues end_colors = this->current_values;
+  LightColorValues end_colors = this->remote_values;
   // If starting a flash if one is already happening, set end values to end values of current flash
   // Hacky but works
   if (this->transformer_ != nullptr)
-    end_colors = this->transformer_->get_end_values();
+    end_colors = this->transformer_->get_target_values();
-  this->transformer_ = make_unique<LightFlashTransformer>(millis(), length, end_colors, target);
+
-  this->remote_values = this->transformer_->get_remote_values();
+  this->transformer_ = make_unique<LightFlashTransformer>(*this);
+  this->transformer_->setup(end_colors, target, length);
+  this->remote_values = target;
 }
 
 void LightState::set_immediately_(const LightColorValues &target, bool set_remote_values) {
@@ -240,10 +244,6 @@ void LightState::set_immediately_(const LightColorValues &target, bool set_remot
   this->next_write_ = true;
 }
 
-void LightState::set_transformer_(std::unique_ptr<LightTransformer> transformer) {
-  this->transformer_ = std::move(transformer);
-}
-
 void LightState::save_remote_values_() {
   LightStateRTCState saved;
   saved.color_mode = this->remote_values.get_color_mode();

esphome/components/light/light_state.h

@@ -157,9 +157,6 @@ class LightState : public Nameable, public Component {
   /// Internal method to set the color values to target immediately (with no transition).
   void set_immediately_(const LightColorValues &target, bool set_remote_values);
 
-  /// Internal method to start a transformer.
-  void set_transformer_(std::unique_ptr<LightTransformer> transformer);
-
   /// Internal method to save the current remote_values to the preferences
   void save_remote_values_();
 

esphome/components/light/light_transformer.h

@@ -1,42 +1,42 @@
 #pragma once
 
-#include "esphome/core/component.h"
 #include "esphome/core/helpers.h"
 #include "light_color_values.h"
 
 namespace esphome {
 namespace light {
 
-/// Base-class for all light color transformers, such as transitions or flashes.
+/// Base class for all light color transformers, such as transitions or flashes.
 class LightTransformer {
  public:
-  LightTransformer(uint32_t start_time, uint32_t length, const LightColorValues &start_values,
+  void setup(const LightColorValues &start_values, const LightColorValues &target_values, uint32_t length) {
-                   const LightColorValues &target_values)
+    this->start_time_ = millis();
-      : start_time_(start_time), length_(length), start_values_(start_values), target_values_(target_values) {}
+    this->length_ = length;
+    this->start_values_ = start_values;
+    this->target_values_ = target_values;
+    this->start();
+  }
 
-  LightTransformer() = delete;
+  /// Indicates whether this transformation is finished.
+  virtual bool is_finished() { return this->get_progress_() >= 1.0f; }
 
-  /// Whether this transformation is finished
+  /// This will be called before the transition is started.
-  virtual bool is_finished() { return this->get_progress() >= 1.0f; }
+  virtual void start() {}
 
-  /// This will be called to get the current values for output.
+  /// This will be called while the transformer is active to apply the transition to the light. Can either write to the
-  virtual LightColorValues get_values() = 0;
+  /// light directly, or return LightColorValues that will be applied.
+  virtual optional<LightColorValues> apply() = 0;
 
-  /// The values that should be reported to the front-end.
+  /// This will be called after transition is finished.
-  virtual LightColorValues get_remote_values() { return this->get_target_values_(); }
+  virtual void stop() {}
 
-  /// The values that should be set after this transformation is complete.
+  const LightColorValues &get_start_values() const { return this->start_values_; }
-  virtual LightColorValues get_end_values() { return this->get_target_values_(); }
 
-  virtual bool publish_at_end() = 0;
+  const LightColorValues &get_target_values() const { return this->target_values_; }
-  virtual bool is_transition() = 0;
-
-  float get_progress() { return clamp((millis() - this->start_time_) / float(this->length_), 0.0f, 1.0f); }
 
  protected:
-  const LightColorValues &get_start_values_() const { return this->start_values_; }
+  /// The progress of this transition, on a scale of 0 to 1.
-
+  float get_progress_() { return clamp((millis() - this->start_time_) / float(this->length_), 0.0f, 1.0f); }
-  const LightColorValues &get_target_values_() const { return this->target_values_; }
 
   uint32_t start_time_;
   uint32_t length_;
@@ -44,69 +44,5 @@ class LightTransformer {
   LightColorValues target_values_;
 };
 
-class LightTransitionTransformer : public LightTransformer {
- public:
-  LightTransitionTransformer(uint32_t start_time, uint32_t length, const LightColorValues &start_values,
-                             const LightColorValues &target_values)
-      : LightTransformer(start_time, length, start_values, target_values) {
-    // When turning light on from off state, use colors from new.
-    if (!this->start_values_.is_on() && this->target_values_.is_on()) {
-      this->start_values_ = LightColorValues(target_values);
-      this->start_values_.set_brightness(0.0f);
-    }
-
-    // When changing color mode, go through off state, as color modes are orthogonal and there can't be two active.
-    if (this->start_values_.get_color_mode() != this->target_values_.get_color_mode()) {
-      this->changing_color_mode_ = true;
-      this->intermediate_values_ = LightColorValues(this->get_start_values_());
-      this->intermediate_values_.set_state(false);
-    }
-  }
-
-  LightColorValues get_values() override {
-    float p = this->get_progress();
-
-    // Halfway through, when intermediate state (off) is reached, flip it to the target, but remain off.
-    if (this->changing_color_mode_ && p > 0.5f &&
-        this->intermediate_values_.get_color_mode() != this->target_values_.get_color_mode()) {
-      this->intermediate_values_ = LightColorValues(this->get_end_values());
-      this->intermediate_values_.set_state(false);
-    }
-
-    LightColorValues &start = this->changing_color_mode_ && p > 0.5f ? this->intermediate_values_ : this->start_values_;
-    LightColorValues &end = this->changing_color_mode_ && p < 0.5f ? this->intermediate_values_ : this->target_values_;
-    if (this->changing_color_mode_)
-      p = p < 0.5f ? p * 2 : (p - 0.5) * 2;
-
-    float v = LightTransitionTransformer::smoothed_progress(p);
-    return LightColorValues::lerp(start, end, v);
-  }
-
-  bool publish_at_end() override { return false; }
-  bool is_transition() override { return true; }
-
-  // This looks crazy, but it reduces to 6x^5 - 15x^4 + 10x^3 which is just a smooth sigmoid-like
-  // transition from 0 to 1 on x = [0, 1]
-  static float smoothed_progress(float x) { return x * x * x * (x * (x * 6.0f - 15.0f) + 10.0f); }
-
- protected:
-  bool changing_color_mode_{false};
-  LightColorValues intermediate_values_{};
-};
-
-class LightFlashTransformer : public LightTransformer {
- public:
-  LightFlashTransformer(uint32_t start_time, uint32_t length, const LightColorValues &start_values,
-                        const LightColorValues &target_values)
-      : LightTransformer(start_time, length, start_values, target_values) {}
-
-  LightColorValues get_values() override { return this->get_target_values_(); }
-
-  LightColorValues get_end_values() override { return this->get_start_values_(); }
-
-  bool publish_at_end() override { return true; }
-  bool is_transition() override { return false; }
-};
-
 }  // namespace light
 }  // namespace esphome

esphome/components/light/transformers.h

@@ -0,0 +1,75 @@
+#pragma once
+
+#include "esphome/core/component.h"
+#include "esphome/core/helpers.h"
+#include "light_color_values.h"
+#include "light_state.h"
+#include "light_transformer.h"
+
+namespace esphome {
+namespace light {
+
+class LightTransitionTransformer : public LightTransformer {
+ public:
+  void start() override {
+    // When turning light on from off state, use colors from target state.
+    if (!this->start_values_.is_on() && this->target_values_.is_on()) {
+      this->start_values_ = LightColorValues(this->target_values_);
+      this->start_values_.set_brightness(0.0f);
+    }
+
+    // When changing color mode, go through off state, as color modes are orthogonal and there can't be two active.
+    if (this->start_values_.get_color_mode() != this->target_values_.get_color_mode()) {
+      this->changing_color_mode_ = true;
+      this->intermediate_values_ = this->start_values_;
+      this->intermediate_values_.set_state(false);
+    }
+  }
+
+  optional<LightColorValues> apply() override {
+    float p = this->get_progress_();
+
+    // Halfway through, when intermediate state (off) is reached, flip it to the target, but remain off.
+    if (this->changing_color_mode_ && p > 0.5f &&
+        this->intermediate_values_.get_color_mode() != this->target_values_.get_color_mode()) {
+      this->intermediate_values_ = this->target_values_;
+      this->intermediate_values_.set_state(false);
+    }
+
+    LightColorValues &start = this->changing_color_mode_ && p > 0.5f ? this->intermediate_values_ : this->start_values_;
+    LightColorValues &end = this->changing_color_mode_ && p < 0.5f ? this->intermediate_values_ : this->target_values_;
+    if (this->changing_color_mode_)
+      p = p < 0.5f ? p * 2 : (p - 0.5) * 2;
+
+    float v = LightTransitionTransformer::smoothed_progress(p);
+    return LightColorValues::lerp(start, end, v);
+  }
+
+ protected:
+  // This looks crazy, but it reduces to 6x^5 - 15x^4 + 10x^3 which is just a smooth sigmoid-like
+  // transition from 0 to 1 on x = [0, 1]
+  static float smoothed_progress(float x) { return x * x * x * (x * (x * 6.0f - 15.0f) + 10.0f); }
+
+  bool changing_color_mode_{false};
+  LightColorValues intermediate_values_{};
+};
+
+class LightFlashTransformer : public LightTransformer {
+ public:
+  LightFlashTransformer(LightState &state) : state_(state) {}
+
+  optional<LightColorValues> apply() override { return this->get_target_values(); }
+
+  // Restore the original values after the flash.
+  void stop() override {
+    this->state_.current_values = this->get_start_values();
+    this->state_.remote_values = this->get_start_values();
+    this->state_.publish_state();
+  }
+
+ protected:
+  LightState &state_;
+};
+
+}  // namespace light
+}  // namespace esphome