feat(screen): stream the display framebuffer to local clients (DisplayFrame mirroring)

src/configuration.h

@@ -637,6 +637,24 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define HAS_SCREEN 0
 #endif
 
+// Display mirroring to the client (FromRadio.display_frame) rides the screen
+// and can be excluded independently with MESHTASTIC_EXCLUDE_SCREEN_MIRROR.
+#if HAS_SCREEN && !defined(MESHTASTIC_EXCLUDE_SCREEN_MIRROR)
+#define HAS_SCREEN_MIRROR 1
+#else
+#define HAS_SCREEN_MIRROR 0
+#endif
+
+// Mirroring MUI (device-ui/LVGL) streams RGB565 dirty rects instead of the
+// 1bpp framebuffer, and needs a device-ui carrying the flush observer. Until
+// that lands upstream the whole path - queue, pool and input seam - compiles
+// out, so a color build that does not opt in carries none of it.
+#if HAS_SCREEN_MIRROR && HAS_TFT && defined(MESHTASTIC_MUI_MIRROR)
+#define HAS_MUI_MIRROR 1
+#else
+#define HAS_MUI_MIRROR 0
+#endif
+
 #ifndef USE_ETHERNET_DEFAULT
 #define USE_ETHERNET_DEFAULT 0
 #endif

src/graphics/HUB75Display.cpp

@@ -3,6 +3,7 @@
 #if defined(USE_HUB75)
 
 #include "HUB75Display.h"
+#include "ScreenMirror.h"
 #include "TFTColorRegions.h"
 #include "TFTPalette.h"
 #include <ESP32-HUB75-MatrixPanel-I2S-DMA.h>
@@ -121,6 +122,9 @@ void HUB75Display::display()
     firstFrame = false;
 #if GRAPHICS_TFT_COLORING_ENABLED
     lastColorSig = colorSig;
+#if HAS_SCREEN_MIRROR
+    graphics::screenMirror.capturePalette(colorSig, onBe, offBe, graphics::colorRegions, graphics::getTFTColorRegionCount());
+#endif
     // Regions are re-registered every frame by the renderers; clear so they
     // don't accumulate across frames.
     graphics::clearTFTColorRegions();

src/graphics/Screen.cpp

@@ -23,6 +23,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "Screen.h"
 #include "NodeDB.h"
 #include "PowerMon.h"
+#include "ScreenMirror.h"
 #include "Throttle.h"
 #include "configuration.h"
 #include "meshUtils.h"
@@ -181,6 +182,18 @@ static void drawLockdownLockScreen(OLEDDisplay *display)
 }
 #endif
 
+// Give ScreenMirror a look at the committed framebuffer (no-op unless armed).
+// Deliberately scoped to updateUiFrame commits: the few direct display()
+// paths it bypasses (EInk re-commits, boot logo) immediately follow or
+// precede a mirrored frame.
+static inline void screenMirrorCapture()
+{
+#if HAS_SCREEN_MIRROR
+    if (screen)
+        screenMirror.onRendered(screen->getDisplayDevice());
+#endif
+}
+
 static inline void updateUiFrame(OLEDDisplayUi *ui)
 {
 #ifdef MESHTASTIC_LOCKDOWN
@@ -208,13 +221,16 @@ static inline void updateUiFrame(OLEDDisplayUi *ui)
             NotificationRenderer::drawBannercallback(display, ui->getUiState());
         }
         display->display();
+        // The mirror sees the LOCKED frame, matching the panel's redaction.
+        screenMirrorCapture();
         return;
     }
 #endif
 #if GRAPHICS_TFT_COLORING_ENABLED
     prepareFrameColorRegions();
 #endif
     ui->update();
+    screenMirrorCapture();
 }
 // Global variables for alert banner - explicitly define with extern "C" linkage to prevent optimization