Freeze display time during partial-buffer updates

esphome/energymonitor.yaml

@@ -142,6 +142,10 @@ font:
       - "\U000F092D" # mdi:wifi-strength-off
 
 globals:
+  - id: display_time
+    type: esphome::ESPTime
+    restore_value: false
+    initial_value: 'esphome::ESPTime{}'
   - id: page_index
     type: int
     restore_value: true
@@ -313,6 +317,9 @@ sensor:
       name: 'WireGuard Latest Handshake'
 
 interval:
+  - interval: 1s
+    then:
+      - script.execute: refresh_display
   - interval: 10s
     then:
       - lambda: |-
@@ -330,10 +337,15 @@ interval:
           if (id(internet_history_count) < 361) id(internet_history_count)++;
 
 script:
+  - id: refresh_display
+    then:
+      # The partial-buffer driver draws multiple strips; freeze time for the entire frame.
+      - lambda: id(display_time) = id(sntp_time).now();
+      - component.update: tft
   - id: show_previous_page
     then:
       - lambda: id(page_index) = (id(page_index) + 4 - 1) % 4;
-      - component.update: tft
+      - script.execute: refresh_display
   - id: toggle_page_mode
     then:
       - lambda: |-
@@ -346,11 +358,11 @@ script:
           } else if (id(page_index) == 3) {
             id(internet_view) = (id(internet_view) + 1) % 3;
           }
-      - component.update: tft
+      - script.execute: refresh_display
   - id: show_next_page
     then:
       - lambda: id(page_index) = (id(page_index) + 1) % 4;
-      - component.update: tft
+      - script.execute: refresh_display
 
 button:
   - platform: template
@@ -419,13 +431,14 @@ display:
     dc_pin: GPIO27
     reset_pin: GPIO33
     invert_colors: true
-    update_interval: 1s
+    update_interval: never
     lambda: |-
+      const auto now = id(display_time);
       it.fill(Color::BLACK);
 
-      if (id(sntp_time).now().is_valid()) {
+      if (now.is_valid()) {
         it.strftime(234, 10, id(font_small), Color::WHITE, TextAlign::TOP_RIGHT,
-                    "%H:%M", id(sntp_time).now());
+                    "%H:%M", now);
       } else {
         it.printf(234, 10, id(font_small), Color::WHITE, TextAlign::TOP_RIGHT, "--:--");
       }
@@ -643,7 +656,6 @@ display:
       }
 
       if (id(page_index) == 2) {
-        const auto now = id(sntp_time).now();
         const Color accent(143, 190, 223);
         const Color gold(255, 170, 40);
         const Color muted(55, 65, 80);