Implement Candy Press effect

* Shift indicator hues with triwave

Author: filterpaper

config.h

@@ -49,14 +49,17 @@
 #endif
 
 #ifdef RGB_MATRIX_ENABLE
-#   define RGB_MATRIX_KEYPRESSES
 #   define RGB_MATRIX_DEFAULT_SPD 128
 #   define RGB_MATRIX_DEFAULT_HUE 180
-#   define ENABLE_RGB_MATRIX_CUSTOM_CANDY_TAP
+#   define ENABLE_RGB_MATRIX_CUSTOM_CANDY_PRESS
 #   define ENABLE_RGB_MATRIX_CUSTOM_CANDY_MOSAIC
-#   define RGB_MATRIX_DEFAULT_MODE RGB_MATRIX_CUSTOM_CANDY_TAP
-#   define DEF_MODE RGB_MATRIX_CUSTOM_CANDY_TAP
+#   define RGB_MATRIX_DEFAULT_MODE RGB_MATRIX_CUSTOM_CANDY_PRESS
+#   define DEF_MODE RGB_MATRIX_CUSTOM_CANDY_PRESS
 #   define CMK_MODE RGB_MATRIX_CUSTOM_CANDY_MOSAIC
+#   if (defined(ENABLE_RGB_MATRIX_CUSTOM_CANDY_TAP) || \
+        defined(ENABLE_RGB_MATRIX_CUSTOM_CANDY_SPLASH))
+#       define RGB_MATRIX_KEYPRESSES
+#   endif
 #endif
 
 // Layout macros

features/rgb_matrix.c

@@ -28,28 +28,28 @@ led_config_t g_led_config = {
 
 
 bool rgb_matrix_indicators_advanced_user(uint8_t led_min, uint8_t led_max) {
-    hsv_t hsv = {};
+    hsv_t   hsv  = {};
+    uint8_t time = scale16by8(g_rgb_timer, qadd8(rgb_matrix_config.speed / 4, 1));
 
     if (get_highest_layer(layer_state) > CMK) {
-        // Scale active layer index to hue value
+        // Scale active layer index to triwave hue range
         hsv   = rgb_matrix_config.hsv;
-        hsv.h = (get_highest_layer(layer_state) - 1) * 85;
+        hsv.h = (triwave8(time) / 8) - ((get_highest_layer(layer_state) - 1) * 85);
     } else if (host_keyboard_led_state().caps_lock) {
         // Apply pulsing brightness to hue value
-        hsv          = (hsv_t){HSV_PINK};
-        uint8_t time = scale16by8(g_rgb_timer, rgb_matrix_config.speed / 4);
-        uint8_t wave = abs8(sin8(time) - 128) * 2;
-        hsv.v        = scale8(wave, hsv.v);
+        hsv   = (hsv_t){HSV_MAGENTA};
+        hsv.v = scale8((abs8(sin8(time) - 128) * 2), hsv.v);
     }
 
     for (uint8_t i = led_min; i < led_max; ++i) {
         uint8_t mods = IS_MODIFIER_FOR_LED(i);
-        if (!mods && !hsv.v) continue;
-
         if (mods) {
-            // Combine modifier bits and scale to hue range
+            // Combine modifier bits and scale to triwave hue range
             hsv   = rgb_matrix_config.hsv;
-            hsv.h = ((mods >> 4) | (mods & 0x0F)) * 17;
+            hsv.h = (triwave8(time) / 8) - (((mods >> 4) | (mods & 0x0F)) * 17);
+        } else if (!hsv.v) {
+            // Skip LEDs if HSV value is zero
+            continue;
         }
         rgb_t rgb = hsv_to_rgb(hsv);
         rgb_matrix_set_color(i, rgb.r, rgb.g, rgb.b);

features/rgb_matrix_user.inc

@@ -95,6 +95,60 @@ static bool CANDY_SPLASH(effect_params_t* params) {
 #endif // ENABLE_RGB_MATRIX_CUSTOM_CANDY_SPLASH
 
 
+#ifdef ENABLE_RGB_MATRIX_CUSTOM_CANDY_PRESS
+RGB_MATRIX_EFFECT(CANDY_PRESS)
+#   ifdef RGB_MATRIX_CUSTOM_EFFECT_IMPLS
+#   include "matrix.h"
+
+// Store current brightness per LED (0 = dark, 255 = full)
+static uint8_t  candy_press_v[RGB_MATRIX_LED_COUNT];
+static uint32_t candy_press_timer;
+
+static bool CANDY_PRESS(effect_params_t* params) {
+    if (params->iter == 0) {
+        if (params->init) memset(candy_press_v, 0, sizeof(candy_press_v));
+
+        // On the first iteration, calculate brightness decay based on time scale since last update
+        uint16_t delta = (uint16_t)MIN(g_rgb_timer - candy_press_timer, 0xFFFFu);
+        uint8_t  decay = (uint8_t)MIN(scale16by8(delta, qadd8(rgb_matrix_config.speed, 1)), 255u);
+        for (uint8_t i = 0; i < RGB_MATRIX_LED_COUNT; ++i) {
+            if (candy_press_v[i]) candy_press_v[i] = qsub8(candy_press_v[i], decay);
+        }
+        candy_press_timer = g_rgb_timer;
+
+        // Scan the key matrix and set brightness to 255 for currently pressed keys
+        for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
+            matrix_row_t row_state = matrix_get_row(row);
+            if (!row_state) continue;
+            for (uint8_t col = 0; col < MATRIX_COLS; col++) {
+                if (!((row_state >> col) & 1)) continue;
+                uint8_t led = g_led_config.matrix_co[row][col];
+                if (led < RGB_MATRIX_LED_COUNT) candy_press_v[led] = 255;
+            }
+        }
+    }
+
+    // Apply a triwave colour effect to all LEDs with brightness based on current
+    // candy_press_v value, creating a pulsing effect that responds to key presses
+    RGB_MATRIX_USE_LIMITS(led_min, led_max);
+    for (uint8_t i = led_min; i < led_max; i++) {
+        if (!candy_press_v[i]) continue;
+        RGB_MATRIX_TEST_LED_FLAGS();
+        uint8_t now = scale16by8(g_rgb_timer, qadd8(rgb_matrix_config.speed / 16, 1));
+        hsv_t   hsv = rgb_matrix_config.hsv;
+        hsv.h       = (triwave8(now) / 4) + (g_rgb_timer / 1024);
+        hsv.v       = scale8(candy_press_v[i], hsv.v);
+        rgb_t   rgb = rgb_matrix_hsv_to_rgb(hsv);
+        rgb_matrix_set_color(i, rgb.r, rgb.g, rgb.b);
+    }
+
+    return rgb_matrix_check_finished_leds(led_max);
+}
+
+#   endif // RGB_MATRIX_CUSTOM_EFFECT_IMPLS
+#endif // ENABLE_RGB_MATRIX_CUSTOM_CANDY_PRESS
+
+
 #ifdef ENABLE_RGB_MATRIX_CUSTOM_CANDY_PULSE
 RGB_MATRIX_EFFECT(CANDY_PULSE)
 #   ifdef RGB_MATRIX_CUSTOM_EFFECT_IMPLS