Added option to invert screen on InkHUD (#7075)

* Added option to invert screen on InkHUD

* Rewrite to make use of existing config.display.displaymode

---------

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

src/graphics/niche/InkHUD/Applets/System/Menu/MenuAction.h

@@ -33,6 +33,7 @@ enum MenuAction {
     LAYOUT,
     TOGGLE_BATTERY_ICON,
     TOGGLE_NOTIFICATIONS,
+    TOGGLE_INVERT_COLOR,
     TOGGLE_12H_CLOCK,
 };
 

src/graphics/niche/InkHUD/Applets/System/Menu/MenuApplet.cpp

@@ -205,6 +205,15 @@ void InkHUD::MenuApplet::execute(MenuItem item)
         settings->optionalFeatures.notifications = !settings->optionalFeatures.notifications;
         break;
 
+    case TOGGLE_INVERT_COLOR:
+        if (config.display.displaymode == meshtastic_Config_DisplayConfig_DisplayMode_INVERTED)
+            config.display.displaymode = meshtastic_Config_DisplayConfig_DisplayMode_DEFAULT;
+        else
+            config.display.displaymode = meshtastic_Config_DisplayConfig_DisplayMode_INVERTED;
+
+        nodeDB->saveToDisk(SEGMENT_CONFIG);
+        break;
+
     case SET_RECENTS:
         // Set value of settings.recentlyActiveSeconds
         // Uses menu cursor to read RECENTS_OPTIONS_MINUTES array (defined at top of this file)
@@ -316,6 +325,10 @@ void InkHUD::MenuApplet::showPage(MenuPage page)
                                  &settings->optionalFeatures.notifications));
         items.push_back(MenuItem("Battery Icon", MenuAction::TOGGLE_BATTERY_ICON, MenuPage::OPTIONS,
                                  &settings->optionalFeatures.batteryIcon));
+
+        invertedColors = (config.display.displaymode == meshtastic_Config_DisplayConfig_DisplayMode_INVERTED);
+        items.push_back(MenuItem("Invert Color", MenuAction::TOGGLE_INVERT_COLOR, MenuPage::OPTIONS, &invertedColors));
+
         items.push_back(
             MenuItem("12-Hour Clock", MenuAction::TOGGLE_12H_CLOCK, MenuPage::OPTIONS, &config.display.use_12h_clock));
         items.push_back(MenuItem("Exit", MenuPage::EXIT));

src/graphics/niche/InkHUD/Applets/System/Menu/MenuApplet.h

@@ -91,6 +91,8 @@ class MenuApplet : public SystemApplet, public concurrency::OSThread
     } cm;
 
     Applet *borrowedTileOwner = nullptr; // Which applet we have temporarily replaced while displaying menu
+
+    bool invertedColors = false; // Helper to display current state of config.display.displaymode in InkHUD options
 };
 
 } // namespace NicheGraphics::InkHUD

src/graphics/niche/InkHUD/Renderer.cpp

@@ -224,6 +224,13 @@ void InkHUD::Renderer::render(bool async)
         renderPlaceholders();
         renderSystemApplets();
 
+        // Invert Buffer if set by user
+        if (config.display.displaymode == meshtastic_Config_DisplayConfig_DisplayMode_INVERTED) {
+            for (size_t i = 0; i < imageBufferWidth * imageBufferHeight; ++i) {
+                imageBuffer[i] = ~imageBuffer[i];
+            }
+        }
+
         // Tell display to begin process of drawing new image
         LOG_INFO("Updating display");
         driver->update(imageBuffer, updateType);