fix(patterns): use preset background fallback across animations

Align pattern background rendering to use preset.background_or(...) and update pulse/radiate single-step behaviour to preserve visible frames and step progression.

src/main.py

@@ -173,13 +173,6 @@ async def presets_loop():
     while True:
         presets.tick()
         wdt.feed()
-        if bool(getattr(presets, "debug", False)):
-            now = utime.ticks_ms()
-            if utime.ticks_diff(now, last_mem_log) >= 5000:
-                gc.collect()
-                print("mem runtime:", {"free": gc.mem_free(), "alloc": gc.mem_alloc()})
-                last_mem_log = now
-        # tick() does not await; yield so UDP hello and HTTP/WebSocket can run.
         await asyncio.sleep(0)
 
 

src/patterns/bar_graph.py

@@ -16,7 +16,7 @@ class BarGraph:
                 target = (self.driver.num_leds * level) // 100
                 lit = self.driver.apply_brightness(colors[0], preset.b)
                 unlit = self.driver.apply_brightness(
-                    colors[-1],
+                    preset.background_or(colors),
                     preset.b,
                 )
                 for i in range(self.driver.num_leds):

src/patterns/blink.py

@@ -9,6 +9,7 @@ class Blink:
         """Blink pattern: toggles LEDs on/off using preset delay, cycling through colors."""
         # Use provided colors, or default to white if none
         colors = preset.c if preset.c else [(255, 255, 255)]
+        bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
         color_index = 0
         state = True  # True = on, False = off
         last_update = utime.ticks_ms()
@@ -25,8 +26,8 @@ class Blink:
                     # Advance to next color for the next "on" phase
                     color_index += 1
                 else:
-                    # "Off" phase should actually be off.
+                    # Inactive phase uses the preset background color.
-                    self.driver.fill((0, 0, 0))
+                    self.driver.fill(bg_color)
                 state = not state
                 last_update = utime.ticks_add(last_update, delay_ms)
             # Yield once per tick so other logic can run

src/patterns/chase.py

@@ -26,7 +26,7 @@ class Chase:
 
         color0 = self.driver.apply_brightness(color0, preset.b)
         color1 = self.driver.apply_brightness(color1, preset.b)
-        bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+        bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
 
         n1 = max(1, int(preset.n1))  # LEDs of color 0
         n2 = max(1, int(preset.n2))  # LEDs of color 1

src/patterns/circle.py

@@ -31,10 +31,10 @@ class Circle:
             base0 = base1 = (255, 255, 255)
         elif len(colors) == 1:
             base0 = colors[0]
-            base1 = colors[-1]
+            base1 = preset.background_or(colors)
         else:
             base0 = colors[0]
-            base1 = colors[-1]
+            base1 = preset.background_or(colors)
 
         color0 = self.driver.apply_brightness(base0, preset.b)
         color1 = self.driver.apply_brightness(base1, preset.b)

src/patterns/clock_sweep.py

@@ -15,7 +15,7 @@ class ClockSweep:
             d = max(1, int(preset.d))
             now = utime.ticks_ms()
             if utime.ticks_diff(now, last) >= d:
-                bg = self.driver.apply_brightness(colors[-1], preset.b)
+                bg = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                 fg = self.driver.apply_brightness(colors[0], preset.b)
                 for i in range(self.driver.num_leds):
                     self.driver.n[i] = bg

src/patterns/comet_dual.py

@@ -17,7 +17,7 @@ class CometDual:
             d = max(1, int(preset.d))
             now = utime.ticks_ms()
             if utime.ticks_diff(now, last) >= d:
-                bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+                bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                 for i in range(self.driver.num_leds):
                     self.driver.n[i] = bg_color
                 c1 = self.driver.apply_brightness(colors[0 % len(colors)], preset.b)

src/patterns/fireflies.py

@@ -16,7 +16,7 @@ class Fireflies:
             d = max(1, int(preset.d))
             now = utime.ticks_ms()
             if utime.ticks_diff(now, last) >= d:
-                bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+                bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                 for i in range(self.driver.num_leds):
                     self.driver.n[i] = bg_color
                 for b in bugs:

src/patterns/heartbeat.py

@@ -17,7 +17,7 @@ class Heartbeat:
             beat_gap = max(20, int(preset.d))
             colors = preset.c if preset.c else [(255, 0, 40)]
             lit_color = self.driver.apply_brightness(colors[0], preset.b)
-            bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+            bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
             phase_durations = (p1, beat_gap, p2, pause)
             phase_colors = (lit_color, bg_color, lit_color, bg_color)
 

src/patterns/marquee.py

@@ -17,7 +17,7 @@ class Marquee:
             now = utime.ticks_ms()
             if utime.ticks_diff(now, last) >= d:
                 c = self.driver.apply_brightness(colors[0], preset.b)
-                bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+                bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                 for i in range(self.driver.num_leds):
                     m = (i + phase) % (on_len + off_len)
                     self.driver.n[i] = c if m < on_len else bg_color

src/patterns/orbit.py

@@ -15,7 +15,7 @@ class Orbit:
             d = max(1, int(preset.d))
             now = utime.ticks_ms()
             if utime.ticks_diff(now, last) >= d:
-                bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+                bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                 for i in range(self.driver.num_leds):
                     self.driver.n[i] = bg_color
                 for k in range(orbits):

src/patterns/pulse.py

@@ -6,19 +6,19 @@ class Pulse:
         self.driver = driver
 
     def run(self, preset):
-        self.driver.off()
-
         # Get colors from preset
         colors = preset.c
         if not colors:
             colors = [(255, 255, 255)]
+        bg_base = preset.background_or(colors)
+        self.driver.fill(self.driver.apply_brightness(bg_base, preset.b))
 
-        color_index = 0
+        color_index = self.driver.step % max(1, len(colors))
         cycle_start = utime.ticks_ms()
 
         # State machine based pulse using a single generator loop
         while True:
-            bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+            bg_color = self.driver.apply_brightness(bg_base, preset.b)
             # Read current timing parameters from preset
             attack_ms = max(0, int(preset.n1))  # Attack time in ms
             hold_ms = max(0, int(preset.n2))    # Hold time in ms
@@ -53,7 +53,8 @@ class Pulse:
                 self.driver.fill(bg_color)
             else:
                 # End of cycle, move to next color and restart timing
-                color_index += 1
+                color_index = (color_index + 1) % max(1, len(colors))
+                self.driver.step = color_index
                 cycle_start = now
                 if not preset.a:
                     break

src/patterns/radiate.py

@@ -17,7 +17,7 @@ class Radiate:
         """
         colors = preset.c if preset.c else [(255, 255, 255)]
         base_on = colors[0]
-        base_off = colors[-1]
+        base_off = preset.background_or(colors)
 
         spacing = max(1, int(preset.n1))
         outward_ms = max(1, int(preset.n2))
@@ -34,8 +34,9 @@ class Radiate:
         dbg_banner = False
 
         if not preset.a:
-            # Single-step render uses only the first instant pulse.
+            # Single-shot mode exits after one rendered frame. Seed the pulse
-            active_pulses = [utime.ticks_ms()]
+            # slightly in the past so this frame is visible before returning.
+            active_pulses = [utime.ticks_add(utime.ticks_ms(), -1)]
 
         while True:
             now = utime.ticks_ms()

src/patterns/rain_drops.py

@@ -16,7 +16,7 @@ class RainDrops:
             d = max(1, int(preset.d))
             now = utime.ticks_ms()
             if utime.ticks_diff(now, last) >= d:
-                bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+                bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                 for i in range(self.driver.num_leds):
                     self.driver.n[i] = bg_color
                 if random.randint(0, 255) < rate:

src/patterns/scanner.py

@@ -27,7 +27,7 @@ class Scanner:
             if utime.ticks_diff(now, last_update) >= delay_ms:
                 base = colors[color_index % len(colors)]
                 base = self.driver.apply_brightness(base, preset.b)
-                bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+                bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                 for i in range(self.driver.num_leds):
                     dist = i - center
                     if dist < 0:

src/patterns/segment_chase.py

@@ -24,7 +24,7 @@ class SegmentChase:
             d = max(1, int(preset.d))
             now = utime.ticks_ms()
             if utime.ticks_diff(now, last) >= d:
-                bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+                bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                 for i in range(self.driver.num_leds):
                     seg_idx = i // seg
                     in_seg = i % seg

src/patterns/snowfall.py

@@ -16,7 +16,7 @@ class Snowfall:
             d = max(1, int(preset.d))
             now = utime.ticks_ms()
             if utime.ticks_diff(now, last) >= d:
-                bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+                bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                 if random.randint(0, 255) < density:
                     flakes.append([self.driver.num_leds - 1, random.randint(0, len(colors)-1)])
                 for i in range(self.driver.num_leds):

src/patterns/strobe_burst.py

@@ -16,7 +16,7 @@ class StrobeBurst:
             cooldown = max(1, int(preset.n3) if int(preset.n3) > 0 else 400)
             on_ms = max(1, int(preset.d) // 2)
             c = self.driver.apply_brightness(colors[0], preset.b)
-            bg_color = self.driver.apply_brightness(colors[-1], preset.b)
+            bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
             now = utime.ticks_ms()
 
             if state == "flash_on":

src/patterns/twinkle.py

@@ -39,7 +39,7 @@ class Twinkle:
         """Twinkle: n1 activity, n2 density; n3/n4 min/max length of adjacent on/off runs."""
         palette = self._palette(preset)
         num = self.driver.num_leds
-        bg_color = self.driver.apply_brightness(palette[-1], preset.b)
+        bg_color = self.driver.apply_brightness(preset.background_or(palette), preset.b)
         if num <= 0:
             while True:
                 yield

src/preset.py

@@ -100,6 +100,9 @@ class Preset:
     def auto(self, value):
         self.a = value
 
+    def background_or(self, colors=None, default=(0, 0, 0)):
+        return default
+
     def to_dict(self):
         return {
             "p": self.p,