[lvgl] Add pause option to round_trip animation timing (#17574)

esphome/components/lvgl/animation.h

@@ -21,12 +21,22 @@ class LvAnimationTiming {
 
 class LvAnimationTimingRoundTrip : public LvAnimationTiming {
  public:
+  // moving_length_ is the fraction of progress spent moving in each direction, in (0, 0.5].
+  // Callers must pass pause in [0, 1) -- pause == 1.0 would make moving_length_ zero and divide by zero below.
+  LvAnimationTimingRoundTrip(float pause) : moving_length_((1.0f - pause) / 2.0f) {}
   float map_progress(float value) override {
-    value *= 2.0f;
-    if (value > 1.0f)
-      return 2.0f - value;
-    return value;
+    if (value < this->moving_length_) {
+      return value / this->moving_length_;
+    }
+    if (value > 1.0f - this->moving_length_) {
+      return (1.0f - value) / this->moving_length_;
+    }
+    // pause in the middle
+    return 1.0f;
   }
+
+ protected:
+  float moving_length_{};
 };
 
 class LvAnimationTimingGravity : public LvAnimationTiming {

esphome/components/lvgl/animation.py

@@ -42,6 +42,7 @@ LvAnimationTimingRoundTrip = lvgl_ns.class_("LvAnimationTimingRoundTrip")
 LvAnimationTimingEaseInOut = lvgl_ns.class_("LvAnimationTimingEaseInOut")
 
 CONF_BOUNCE = "bounce"
+CONF_PAUSE = "pause"
 
 
 def timing_class(name, extras=None):
@@ -60,10 +61,20 @@ TIMING_SCHEMA = cv.maybe_simple_value(
     cv.typed_schema(
         dict(
             [
-                timing_class("round_trip"),
+                timing_class(
+                    "round_trip",
+                    {
+                        cv.Optional(CONF_PAUSE, default=0.0): cv.All(
+                            cv.percentage,
+                            cv.float_range(
+                                min=0.0, max=1.0, min_included=True, max_included=False
+                            ),
+                        )
+                    },
+                ),
                 timing_class(
                     "ease_in_out",
-                    {cv.Optional(CONF_WEIGHT, default=2.0): lv_positive_float},
+                    {cv.Optional(CONF_WEIGHT, default=1.0): cv.zero_to_one_float},
                 ),
                 timing_class(
                     "gravity",

tests/component_tests/lvgl/test_animation.py

@@ -169,14 +169,27 @@ class TestTimingSchema:
     def test_round_trip_string(self) -> None:
         assert TIMING_SCHEMA("round_trip")["type"] == "round_trip"
 
+    def test_round_trip_default_pause(self) -> None:
+        # Back-compat default: no pause, matching the pre-existing round_trip behavior.
+        assert TIMING_SCHEMA("round_trip")["pause"] == pytest.approx(0.0)
+
+    def test_round_trip_pause_percentage_string(self) -> None:
+        result = TIMING_SCHEMA({"type": "round_trip", "pause": "50%"})
+        assert result["pause"] == pytest.approx(0.5)
+
+    def test_round_trip_pause_rejects_one(self) -> None:
+        # pause == 1.0 would make moving_length_ zero and divide by zero in map_progress.
+        with pytest.raises((Invalid, MultipleInvalid)):
+            TIMING_SCHEMA({"type": "round_trip", "pause": 1.0})
+
     def test_ease_in_out_default_weight(self) -> None:
         result = TIMING_SCHEMA("ease_in_out")
         assert result["type"] == "ease_in_out"
-        assert result["weight"] == pytest.approx(2.0)
+        assert result["weight"] == pytest.approx(1.0)
 
     def test_ease_in_out_custom_weight(self) -> None:
-        result = TIMING_SCHEMA({"type": "ease_in_out", "weight": 3})
-        assert result["weight"] == pytest.approx(3.0)
+        result = TIMING_SCHEMA({"type": "ease_in_out", "weight": 0.5})
+        assert result["weight"] == pytest.approx(0.5)
 
     def test_gravity_defaults(self) -> None:
         result = TIMING_SCHEMA("gravity")

tests/components/lvgl/lvgl-package.yaml

@@ -174,7 +174,8 @@ lvgl:
     - id: anim_color
       duration: 2s
       timing:
-        - round_trip
+        - type: round_trip
+          pause: 0.5
         - type: gravity
           bounce: 0.3
           acceleration: 0.8
@@ -1557,17 +1558,20 @@ font:
 
 image:
   - id: cat_image
+    platform: file
     resize: 256x48
     file: $component_dir/logo-text.svg
     type: RGB565
     transparency: alpha_channel
   - id: dog_image
+    platform: file
     file: $component_dir/logo-text.svg
     resize: 256x48
     type: BINARY
     transparency: chroma_key
 
   - id: alert
+    platform: file
     file: $component_dir/logo-text.svg
     type: grayscale
     resize: 100x100

tests/components/lvgl/test.host.yaml

@@ -39,7 +39,7 @@ lvgl:
         timing:
           - round_trip
           - type: ease_in_out
-            weight: 3
+            weight: 0.5
         on_start:
           - logger.log: anim started
         on_stop: