Adding loop function

arduino/cosplay_lights/lightshow_format.h

@@ -12,16 +12,21 @@
 #include <avr/pgmspace.h>
 #include <stdint.h>
 
+// Show playback modes.
+#define SHOW_LOOP   0  // repeat the show indefinitely
+#define SHOW_SINGLE 1  // play once, then auto-advance to the next show
+
 // One step in a lightshow: a target color and the time to reach it.
 struct Step {
     uint8_t  r, g, b;        // Target RGB color (0–255 each)
     uint16_t duration_ms;    // Milliseconds to fade from the previous color (0 = instant)
 };
 
-// Descriptor for one complete show: a pointer to its PROGMEM Step array and its length.
+// Descriptor for one complete show.
 struct ShowDef {
     const Step* steps;    // Pointer to a PROGMEM Step array
     uint16_t    length;   // Number of steps in the array
+    uint8_t     mode;     // SHOW_LOOP or SHOW_SINGLE
 };
 
 // Read one Step from PROGMEM into a regular struct.
@@ -41,5 +46,6 @@ inline ShowDef read_show_def(const ShowDef* ptr) {
     ShowDef sd;
     sd.steps  = (const Step*)pgm_read_word(&ptr->steps);
     sd.length = pgm_read_word(&ptr->length);
+    sd.mode   = pgm_read_byte(&ptr->mode);
     return sd;
 }