RGB rainbow effect working

FIRMWARE/src/buttons.c

@@ -13,6 +13,8 @@
 #include "hardware/gpio.h"
 #include "hardware/timer.h"
 
+#include "rgb.h"
+
 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
 
 static const struct button {
@@ -75,6 +77,7 @@ uint16_t button_read()
             if (sw_pressed != sw_val[i]) {
                 sw_val[i] = sw_pressed;
                 sw_freeze_time[i] = now + DEBOUNCE_FREEZE_TIME_US;
+                rgb_speed_up();
             }
         }
 

FIRMWARE/src/rgb.c

@@ -12,6 +12,7 @@
 
 #include "pico/multicore.h"
 #include "hardware/pio.h"
+#include "hardware/timer.h"
 
 #include "ws2812.pio.h"
 
@@ -27,6 +28,65 @@ static inline uint32_t urgb_u32(uint8_t r, uint8_t g, uint8_t b)
     return ((uint32_t)r << 8) | ((uint32_t)g << 16) | (uint32_t)b;
 }
 
+
+/* 6 segment regular hsv color wheel, better color cycle
+ * https://www.arnevogel.com/rgb-rainbow/
+ * https://www.instructables.com/How-to-Make-Proper-Rainbow-and-Random-Colors-With-/
+ */
+uint32_t color_wheel(int index)
+{
+    uint32_t section = index / 256 % 6;
+    uint8_t incr = index % 256;
+    uint8_t decr = 255 - incr;
+    if (section == 0) {
+        return urgb_u32(incr, 0, 255);
+    } else if (section == 1) {
+        return urgb_u32(255, 0, decr);
+    } else if (section == 2) {
+        return urgb_u32(255, incr, 0);
+    } else if (section == 3) {
+        return urgb_u32(decr, 255, 0);
+    } else if (section == 4) {
+        return urgb_u32(0, 255, incr);
+    } else {
+        return urgb_u32(0, decr, 255);
+    }
+}
+
+uint32_t color[10];
+uint32_t rotator = 0;
+uint32_t speed = 100;
+uint32_t pitch = 151;
+
+void rotate()
+{
+    rotator += speed;
+
+    for (int i = 0; i < sizeof(color); i++) {
+        put_pixel(color_wheel(rotator + pitch * i));
+    }
+}
+
+void rgb_speed_up()
+{
+    if (speed < 100) {
+        speed++;
+    }
+}
+
+#define SPEED_DOWN_INTERVAL 200000ULL
+void rgb_speed_down()
+{
+    static uint64_t next_change_time = 0;
+    uint64_t now = time_us_64();
+    if (now >= next_change_time) {
+        next_change_time = now + SPEED_DOWN_INTERVAL;
+        if (speed > 5) {
+            speed = speed * 95 / 100;
+        }
+    }
+}
+
 static uint32_t logo_color = 0;
 
 void rgb_update_logo(uint8_t r, uint8_t g, uint8_t b)
@@ -37,9 +97,13 @@ void rgb_update_logo(uint8_t r, uint8_t g, uint8_t b)
 void rgb_entry()
 {
     while (1) {
+/*
         for (int i = 0; i < 10; i++) {
             put_pixel(logo_color);
         }
+*/
+        rotate();
+        rgb_speed_down();
         sleep_ms(10);
     }
 }

FIRMWARE/src/rgb.h

@@ -10,5 +10,6 @@
 
 void rgb_init();
 void rgb_update_logo(uint8_t r, uint8_t g, uint8_t b);
+void rgb_speed_up();
 
 #endif