Implement animation activation/deactivation API and frame scheduling

app/include/drivers/animation.h

@@ -31,9 +31,25 @@ struct animation_pixel {
 extern "C" {
 #endif
 
+/**
+ * @typedef animation_start
+ * @brief Callback API for starting an animation.
+ *
+ * @see animation_start() for argument descriptions.
+ */
+typedef void (*animation_api_start)(const struct device *dev);
+
+/**
+ * @typedef animation_stop
+ * @brief Callback API for stopping an animation.
+ *
+ * @see animation_stop() for argument descriptions.
+ */
+typedef void (*animation_api_stop)(const struct device *dev);
+
 /**
  * @typedef animation_render_frame
- * @brief Callback API for generating the next animation frame
+ * @brief Callback API for generating the next animation frame.
  *
  * @see animation_render_frame() for argument descriptions.
  */
@@ -41,9 +57,23 @@ typedef void (*animation_api_render_frame)(const struct device *dev, struct anim
                                            size_t num_pixels);
 
 struct animation_api {
+    animation_api_start on_start;
+    animation_api_stop on_stop;
     animation_api_render_frame render_frame;
 };
 
+static inline void animation_start(const struct device *dev) {
+    const struct animation_api *api = (const struct animation_api *)dev->api;
+
+    return api->on_start(dev);
+}
+
+static inline void animation_stop(const struct device *dev) {
+    const struct animation_api *api = (const struct animation_api *)dev->api;
+
+    return api->on_stop(dev);
+}
+
 static inline void animation_render_frame(const struct device *dev, struct animation_pixel *pixels,
                                           size_t num_pixels) {
     const struct animation_api *api = (const struct animation_api *)dev->api;

app/include/zmk/animation.h

@@ -78,6 +78,8 @@ bool zmk_cmp_hsl(const struct zmk_color_hsl *a, const struct zmk_color_hsl *b);
 void zmk_interpolate_hsl(const struct zmk_color_hsl *from, const struct zmk_color_hsl *to,
                          struct zmk_color_hsl *result, float step);
 
+void zmk_animation_request_frames(uint32_t frames);
+
 struct zmk_color_rgb __zmk_apply_blending_mode(struct zmk_color_rgb base_value,
                                                struct zmk_color_rgb blend_value, uint8_t mode);
 

app/src/animation/animation.c

@@ -77,6 +77,11 @@ static const size_t pixels_size = DT_INST_PROP_LEN(0, pixels);
  */
 static struct led_rgb px_buffer[DT_INST_PROP_LEN(0, pixels)];
 
+/**
+ * Counter for animation frames that have been requested but have yet to be executed.
+ */
+static uint32_t animation_timer_countdown = 0;
+
 /**
  * Conditional implementation of zmk_animation_get_pixel_by_key_position
  * if key-pixels is set.
@@ -103,6 +108,7 @@ uint8_t zmk_animation_get_pixel_distance(size_t pixel_idx, size_t other_pixel_id
 #endif
 
 static void zmk_animation_tick(struct k_work *work) {
+    LOG_DBG("Animation tick");
     animation_render_frame(animation_root, &pixels[0], pixels_size);
 
     for (size_t i = 0; i < pixels_size; ++i) {
@@ -120,10 +126,29 @@ static void zmk_animation_tick(struct k_work *work) {
 
 K_WORK_DEFINE(animation_work, zmk_animation_tick);
 
-static void zmk_animation_tick_handler(struct k_timer *timer) { k_work_submit(&animation_work); }
+static void zmk_animation_tick_handler(struct k_timer *timer) {
+    if (--animation_timer_countdown == 0) {
+        k_timer_stop(timer);
+    }
+
+    k_work_submit(&animation_work);
+}
 
 K_TIMER_DEFINE(animation_tick, zmk_animation_tick_handler, NULL);
 
+void zmk_animation_request_frames(uint32_t frames) {
+    if (frames <= animation_timer_countdown) {
+        return;
+    }
+
+    if (animation_timer_countdown == 0) {
+        k_timer_start(&animation_tick, K_MSEC(1000 / CONFIG_ZMK_ANIMATION_FPS),
+                      K_MSEC(1000 / CONFIG_ZMK_ANIMATION_FPS));
+    }
+
+    animation_timer_countdown = frames;
+}
+
 static int zmk_animation_init(const struct device *dev) {
 #if defined(CONFIG_ZMK_ANIMATION_PIXEL_DISTANCE) && (CONFIG_ZMK_ANIMATION_PIXEL_DISTANCE == 1)
     // Prefill the pixel distance lookup table
@@ -140,7 +165,7 @@ static int zmk_animation_init(const struct device *dev) {
 
     LOG_INF("ZMK Animation Ready");
 
-    k_timer_start(&animation_tick, K_NO_WAIT, K_MSEC(1000 / CONFIG_ZMK_ANIMATION_FPS));
+    animation_start(animation_root);
 
     return 0;
 }

app/src/animation/animation_compose.c

@@ -36,9 +36,27 @@ static void animation_compose_render_frame(const struct device *dev, struct anim
     }
 }
 
+static void animation_compose_start(const struct device *dev) {
+    const struct animation_compose_config *config = dev->config;
+
+    for (size_t i = 0; i < config->animations_size; ++i) {
+        animation_start(config->animations[i]);
+    }
+}
+
+static void animation_compose_stop(const struct device *dev) {
+    const struct animation_compose_config *config = dev->config;
+
+    for (size_t i = 0; i < config->animations_size; ++i) {
+        animation_stop(config->animations[i]);
+    }
+}
+
 static int animation_compose_init(const struct device *dev) { return 0; }
 
 static const struct animation_api animation_compose_api = {
+    .on_start = animation_compose_start,
+    .on_stop = animation_compose_stop,
     .render_frame = animation_compose_render_frame,
 };
 

app/src/animation/animation_ripple.c

@@ -76,6 +76,8 @@ static int animation_ripple_on_key_press(const struct device *dev, const zmk_eve
     data->events_end = (data->events_end + 1) % config->event_buffer_size;
     data->num_events += 1;
 
+    zmk_animation_request_frames(config->event_frames);
+
     return 0;
 }
 
@@ -96,8 +98,8 @@ static void animation_ripple_render_frame(const struct device *dev, struct anima
             uint8_t pixel_distance = zmk_animation_get_pixel_distance(event->pixel_id, j);
 
             if (config->ripple_width > abs(pixel_distance - event->distance)) {
-                float intensity =
+                float intensity = 1.0f - (float)abs(pixel_distance - event->distance) /
-                    1.0f - (float)abs(pixel_distance - event->distance) / (float)config->ripple_width;
+                                             (float)config->ripple_width;
 
                 struct zmk_color_rgb color = {
                     .r = intensity * data->color_rgb.r,
@@ -125,6 +127,19 @@ static void animation_ripple_render_frame(const struct device *dev, struct anima
     }
 }
 
+static void animation_ripple_start(const struct device *dev) {
+    // Nothing to do.
+}
+
+static void animation_ripple_stop(const struct device *dev) {
+    struct animation_ripple_data *data = dev->data;
+
+    // Cancel the processing of any ongoing events.
+    data->num_events = 0;
+    data->events_start = 0;
+    data->events_end = 0;
+}
+
 static int animation_ripple_init(const struct device *dev) {
     const struct animation_ripple_config *config = dev->config;
     struct animation_ripple_data *data = dev->data;
@@ -135,6 +150,8 @@ static int animation_ripple_init(const struct device *dev) {
 }
 
 static const struct animation_api animation_ripple_api = {
+    .on_start = animation_ripple_start,
+    .on_stop = animation_ripple_stop,
     .render_frame = animation_ripple_render_frame,
 };
 

app/src/animation/animation_solid.c

@@ -25,23 +25,16 @@ struct animation_solid_config {
 };
 
 struct animation_solid_data {
-    bool has_changed;
-
     uint16_t counter;
 
     struct zmk_color_hsl current_hsl;
     struct zmk_color_rgb current_rgb;
 };
 
-static void animation_solid_tick(const struct device *dev) {
+static void animation_solid_update_color(const struct device *dev) {
     const struct animation_solid_config *config = dev->config;
     struct animation_solid_data *data = dev->data;
 
-    // Animation only contains a single color, nothing to do
-    if (config->num_colors == 1) {
-        return;
-    }
-
     const size_t from = data->counter / config->transition_duration;
     const size_t to = (from + 1) % config->num_colors;
 
@@ -51,8 +44,6 @@ static void animation_solid_tick(const struct device *dev) {
                         (data->counter % config->transition_duration) /
                             (float)config->transition_duration);
 
-    data->has_changed = !zmk_cmp_hsl(&data->current_hsl, &next_hsl);
-
     data->current_hsl = next_hsl;
     zmk_hsl_to_rgb(&data->current_hsl, &data->current_rgb);
 
@@ -64,11 +55,26 @@ static void animation_solid_render_frame(const struct device *dev, struct animat
     const struct animation_solid_config *config = dev->config;
     struct animation_solid_data *data = dev->data;
 
-    animation_solid_tick(dev);
-
     for (size_t i = 0; i < config->pixel_map_size; ++i) {
         pixels[config->pixel_map[i]].value = data->current_rgb;
     }
+
+    if (config->num_colors == 1) {
+        return;
+    }
+
+    // Request frames on counter reset
+    if (data->counter == 0) {
+        zmk_animation_request_frames(config->duration);
+    }
+
+    animation_solid_update_color(dev);
+}
+
+static void animation_solid_start(const struct device *dev) { zmk_animation_request_frames(1); }
+
+static void animation_solid_stop(const struct device *dev) {
+    // Nothing to do.
 }
 
 static int animation_solid_init(const struct device *dev) {
@@ -80,16 +86,12 @@ static int animation_solid_init(const struct device *dev) {
 
     zmk_hsl_to_rgb(&data->current_hsl, &data->current_rgb);
 
-    // if (config->num_colors == 1) {
-    //     return 0;
-    // }
-
-    // start timer here, so the only option is inline
-
     return 0;
 }
 
 static const struct animation_api animation_solid_api = {
+    .on_start = animation_solid_start,
+    .on_stop = animation_solid_stop,
     .render_frame = animation_solid_render_frame,
 };