added rounding for the lower end of the LED values

keyboards/fjlabs/vanguard65/keymaps/via/keymap.c

@@ -30,6 +30,32 @@ enum custom_keycodeas {
 };
 
 
+// Set up EEPROM. Mostly boilerplate from QMK docs
+typedef union {
+    uint32_t raw;
+    struct {
+        uint8_t slider_func_state : 8; // Hold only the slider function state. Will be a low value integer, so 8 bits will be used to store.
+    };
+} user_config_t;
+user_config_t user_config; 
+uint8_t slider_func = 0;
+
+// On keyboard initialization, pull the EEPROM values
+void keyboard_post_init_user(void) {
+    // Call the keymap level matrix init.
+
+    user_config.raw = eeconfig_read_user();
+
+    slider_func = user_config.slider_func_state;
+};
+
+// When the EEPROM gets forcefully reset, set the initialization value
+void eeconfig_init_user(void) {
+    user_config.raw = 0;
+    user_config.slider_func_state = 0;
+    eeconfig_update_user(user_config.raw);
+}
+
 #if defined(ENCODER_MAP_ENABLE)
 const uint16_t PROGMEM encoder_map[][NUM_ENCODERS][2] = {
     [_LAYER1] = { ENCODER_CCW_CW(KC_VOLD, KC_VOLU) },
@@ -97,8 +123,88 @@ bool process_record_user(uint16_t keycode, keyrecord_t *record) {
     };
 }
 
+// ====== Process VIA Custom UI ======
+// enum for the Value ID of the slider control
+enum via_slider_control {
+    id_slider_func = 1
+};
+
+// Define the function to set the slider value
+void slider_func_set_value ( uint8_t *data ) {
+    // data = [ value_id, value_data ]
+    uint8_t *value_id   = &(data[0]);
+    uint8_t *value_data = &(data[1]);
+
+    switch ( *value_id )
+    {
+        case id_slider_func:
+        {
+            slider_func = *value_data;
+            user_config.slider_func_state = *value_data;
+            eeconfig_update_user(user_config.raw); // Going to set it here instead of separately in the VIA save function. No point since this value is not being toggled very often
+            break;
+        }
+    }
+}
+
+// Define the function to read the slider value [so that VIA UI knows what to display]
+void slider_func_get_value( uint8_t *data ) {
+    // data = [ value_id, value_data ]
+    uint8_t *value_id   = &(data[0]);
+    uint8_t *value_data = &(data[1]);
+
+    switch ( *value_id )
+    {
+        case id_slider_func:
+        {
+            *value_data = slider_func;
+            break;
+        }
+    }
+}
+
+// Boilerplate from VIA Custom UI Documentation. Listen on the custom command channel, 
+void via_custom_value_command_kb(uint8_t *data, uint8_t length) {
+    // data = [ command_id, channel_id, value_id, value_data ]
+    uint8_t *command_id        = &(data[0]);
+    uint8_t *channel_id        = &(data[1]);
+    uint8_t *value_id_and_data = &(data[2]);
+
+    if ( *channel_id == id_custom_channel ) {
+        switch ( *command_id )
+        {
+            case id_custom_set_value:
+            {
+                slider_func_set_value(value_id_and_data);
+                break;
+            }
+            case id_custom_get_value:
+            {
+                slider_func_get_value(value_id_and_data);
+                break;
+            }
+            case id_custom_save:
+            {
+                //buttglow_config_save(); // Not doing this
+                break;
+            }
+            default:
+            {
+                // Unhandled message.
+                *command_id = id_unhandled;
+                break;
+            }
+        }
+        return;
+    }
+
+    // Return the unhandled state
+    *command_id = id_unhandled;
+
+    // DO NOT call raw_hid_send(data,length) here, let caller do this
+}
+
 /* MIDI Slider controls */
-uint16_t denoise_level = 16;
 uint8_t last_val = 0;
 uint8_t rgb_hue = 0;
 uint8_t rgb_sat = 0;
@@ -108,9 +214,37 @@ void slider(void) {
     uint8_t current_val = analogReadPin(SLIDER_PINA) >>3;
 
     if ( last_val - current_val < -1 || last_val - current_val > 1 ) { 
-        rgb_hue = rgblight_get_hue(); // Pull current hue and saturation values since we're just adjusting brightness
-        rgb_sat = rgblight_get_sat();
-        rgblight_sethsv(rgb_hue, rgb_sat, current_val * 2);
+
+        // Underglow RGB Brightness
+        if ( slider_func == 0 ) {
+            uint8_t rounded_val = 0;
+            rgb_hue = rgblight_get_hue(); // Pull current hue and saturation values since we're just adjusting brightness
+            rgb_sat = rgblight_get_sat();
+
+            // Since the lower end range of the slider can be a little bit noisy, it's going to make the zero-value a little hard to hit when it bounces around between 0-1-2. Better off to round any super low values to zero so the lights will affirmatively turn off at lower values.
+            if ( current_val < 3 ) {
+                rounded_val = 0;
+            } else {
+                rounded_val = current_val;
+            }
+
+            rgblight_sethsv(rgb_hue, rgb_sat, rounded_val * 2); // At 8 bits, it's going to be 0-128, so double to get full range.
+        }
+
+        // MIDI CC 90
+        else if ( slider_func == 1 ) {
+            midi_send_cc(&midi_device, 0, 90, current_val ); // (&midi_device, chan, message, highest control value - (current pin reading) >>resolution)
+        }
+
+        // Layer shift between layers 1 - 4 
+        else if ( slider_func == 2 ) {
+            layer_move(current_val >>5);
+        }
+
+        else {
+            return;
+        }
+
         last_val = current_val;
     }
 }