Add new pattern 'alternating_pulse' (ap): odd beat pulses color1 on odd bars, even beat pulses color2 on even bars; preserve existing alternating_phase; compact payloads and white guard retained

lighting_config.json

@@ -42,8 +42,8 @@
     }
   ],
   "selected_color_indices": [
-    5,
-    2
+    4,
+    3
   ],
   "pattern_parameters": {
     "alternating": {
@@ -136,6 +136,13 @@
       "n2": 10,
       "n3": 1,
       "n4": 1
+    },
+    "alternating_pulse": {
+      "delay": 100,
+      "n1": 10,
+      "n2": 10,
+      "n3": 1,
+      "n4": 1
     }
   }
 }

src/control_server.py

@@ -47,6 +47,8 @@ PATTERN_NAMES = {
     "specto": "s",
     "radiate": "rd",
     "segmented_movement": "sm",
+    # New: alternate two palette colors by pulsing per beat (backend-only logical name)
+    "alternating_pulse": "apu",
     # Short names pass through (for frontend use)
     "o": "o",
     "f": "f",
@@ -415,6 +417,47 @@ class LightingController:
 
         await self.led_controller.send_data(payload)
 
+    async def _handle_alternating_pulse(self):
+        """Handle APU: color1 on odd beat for odd bars, color2 on even beat for even bars."""
+        phase = self.beat_index % 2
+        color1 = self._palette_color(0)
+        color2 = self._palette_color(1)
+        if color1 == (255, 255, 255):
+            color1 = (254, 254, 254)
+        if color2 == (255, 255, 255):
+            color2 = (254, 254, 254)
+
+        # Define bar groups by numeric parity
+        even_bars = ["100", "102", "104", "106"]
+        odd_bars = ["101", "103", "105", "107"]
+
+        # Default: turn bars off this beat
+        payload = {
+            "d": {
+                "t": "b",
+                "pt": "o",  # off by default
+                # Provide pulse envelope params in defaults for bars we enable
+                "n1": self.n1,
+                "n2": self.n2,
+                "dl": self.delay,
+            }
+        }
+
+        # Activate the correct half with the correct color
+        if phase == 0:
+            # Even beat -> even bars use color2
+            active_bars = even_bars
+            active_color = color2
+        else:
+            # Odd beat -> odd bars use color1
+            active_bars = odd_bars
+            active_color = color1
+
+        for bar_name in active_bars:
+            payload[bar_name] = {"pt": "p", "cl": [active_color]}
+
+        await self.led_controller.send_data(payload)
+
     async def handle_beat(self, bpm_value):
         """Handle beat from sound detector."""
         if not self.beat_sending_enabled or not self.current_pattern:
@@ -435,6 +478,8 @@ class LightingController:
             await self._handle_sequential_pulse()
         elif self.current_pattern == "alternating_phase":
             await self._handle_alternating_phase()
+        elif self.current_pattern == "alternating_pulse":
+            await self._handle_alternating_pulse()
         elif self.current_pattern:
             await self._send_normal_pattern()
 
@@ -645,6 +690,9 @@ class ControlServer:
                 self.lighting_controller._save_pattern_parameters(self.lighting_controller.current_pattern)
             
             # Switch to new pattern and load its parameters
+            # Normalize shortnames for backend-only patterns
+            if pattern == "ap":
+                pattern = "alternating_pulse"
             self.lighting_controller.current_pattern = pattern
             self.lighting_controller._load_pattern_parameters(pattern)