Add WiFi setup QR to ESP32 displays

examples/companion_radio/main.cpp

@@ -70,6 +70,7 @@ MultiSerialInterface interface_manager;
     #include <helpers/CompanionWiFiNtpPolicy.h>
     #include <helpers/ui/DisplayTextLayout.h>
     #include <helpers/ui/IndicatorRenderProfile.h>
+    #include <helpers/ui/WiFiSetupQrDisplay.h>
     #include <helpers/esp32/SntpOperationCoordinator.h>
     #include <helpers/esp32/TlsClockValidity.h>
     #include <helpers/esp32/WiFiRadioPolicy.h>
@@ -1286,6 +1287,11 @@ void halt() {
       char setup_ip[16] = {0};
       if (WebConfigServer::getSetupInfo(setup_ssid, sizeof(setup_ssid),
                                         setup_ip, sizeof(setup_ip))) {
+        if (mesh::ui::drawWiFiSetupQr(
+                *companion_setup_display, setup_ssid, setup_ip)) {
+          companion_setup_display->endFrame();
+          return;
+        }
         if (hasLargeCompanionSetupDisplay()) {
           renderLargeCompanionSetupDisplay(
               "WebUI setup", "Join open WiFi:", setup_ssid, setup_ip, false);
@@ -1749,7 +1755,11 @@ void setup() {
   }
 #if defined(ESP32) && defined(WIFI_SSID)
   companion_display_available = disp != NULL;
+#if defined(SENSECAP_INDICATOR_LORA)
   companion_display_begin_status = display.beginStatus();
+#else
+  companion_display_begin_status = companion_display_available ? 1 : 0;
+#endif
 #endif
 #endif
 

examples/simple_repeater/UITask.cpp

@@ -2,6 +2,7 @@
 #include "target.h"
 #include <Arduino.h>
 #include <helpers/CommonCLI.h>
+#include <helpers/ui/WiFiSetupQrDisplay.h>
 
 #ifdef DISPLAY_REDRAW_ON_CHANGE
 #include <helpers/ui/DisplayFrameSignature.h>
@@ -175,6 +176,9 @@ void UITask::renderCurrScreen() {
     char wc_ssid[33], wc_ip[16];
     if (WebConfigServer::getSetupInfo(wc_ssid, sizeof(wc_ssid), wc_ip, sizeof(wc_ip))) {
       // setup portal active: show join instructions instead of the home screen
+      if (mesh::ui::drawWiFiSetupQr(*_display, wc_ssid, wc_ip)) {
+        return;
+      }
       _display->setTextSize(1);
       _display->setColor(UIColor::corp_blue);
       _display->setCursor(0, 0);

examples/simple_room_server/UITask.cpp

@@ -4,6 +4,7 @@
 #endif
 #include <Arduino.h>
 #include <helpers/CommonCLI.h>
+#include <helpers/ui/WiFiSetupQrDisplay.h>
 
 #ifdef DISPLAY_REDRAW_ON_CHANGE
 #include <helpers/ui/DisplayFrameSignature.h>
@@ -175,6 +176,9 @@ void UITask::renderCurrScreen() {
     char wc_ssid[33], wc_ip[16];
     if (WebConfigServer::getSetupInfo(wc_ssid, sizeof(wc_ssid), wc_ip, sizeof(wc_ip))) {
       // setup portal active: show join instructions instead of the home screen
+      if (mesh::ui::drawWiFiSetupQr(*_display, wc_ssid, wc_ip)) {
+        return;
+      }
       _display->setTextSize(1);
       _display->setColor(UIColor::corp_blue);
       _display->setCursor(0, 0);

platformio.ini

@@ -89,7 +89,10 @@ lib_deps = ${arduino_base.lib_deps}
   ESP32Async/AsyncTCP @ 3.5.0
   ESP32Async/ESPAsyncWebServer @ 3.12.0
   bblanchon/ArduinoJson @ 7.4.3
+  ; Generic WiFi-join QR rendering is linked only by ESP32 display builds.
+  ricmoo/QRCode @ 0.0.1
 build_src_filter = ${arduino_base.build_src_filter}
+  +<helpers/ui/DisplayDriver.cpp>
   +<helpers/esp32/WebConfigServer.cpp>
   +<helpers/esp32/PortableErrorStrings.cpp>
   +<helpers/esp32/WiFiOtaSeeder.cpp>

src/helpers/esp32/WebConfigServer.h

@@ -30,6 +30,7 @@
 #include <helpers/WebConfigBatch.h>
 #include <helpers/WiFiPowerSave.h>
 #include <helpers/WiFiReconnectPolicy.h>
+#include <helpers/ui/DisplayBuildFlags.h>
 
 class AsyncWebServer;
 class AsyncWebServerRequest;
@@ -53,7 +54,12 @@ class DNSServer;
   #define WEBCONFIG_SESSION_TTL_MS      (20UL * 60UL * 1000UL)
 #endif
 #ifndef WEBCONFIG_AP_PREFIX
-  #define WEBCONFIG_AP_PREFIX "MeshCore-Setup"
+  #if defined(MESHCORE_HAS_REAL_DISPLAY)
+    // Keeps an open-network WiFi QR in Version 1 on 64-pixel-high screens.
+    #define WEBCONFIG_AP_PREFIX "MC"
+  #else
+    #define WEBCONFIG_AP_PREFIX "MeshCore-Setup"
+  #endif
 #endif
 
 class WebConfigServer {

src/helpers/ui/DisplayBuildFlags.h

@@ -0,0 +1,18 @@
+#pragma once
+
+// DISPLAY_CLASS is supplied as a build token (for example SSD1306Display).
+// Convert it to a boolean that shared ESP32 code can use without including a
+// concrete driver. Undefined identifiers evaluate to zero in a #if expression.
+#define MESHCORE_NULL_DISPLAY_CLASS_NullDisplayDriver 1
+#define MESHCORE_DISPLAY_TOKEN_JOIN_INNER(prefix, name) prefix##name
+#define MESHCORE_DISPLAY_TOKEN_JOIN(prefix, name) \
+  MESHCORE_DISPLAY_TOKEN_JOIN_INNER(prefix, name)
+
+#if defined(DISPLAY_CLASS) \
+    && !MESHCORE_DISPLAY_TOKEN_JOIN(MESHCORE_NULL_DISPLAY_CLASS_, DISPLAY_CLASS)
+  #define MESHCORE_HAS_REAL_DISPLAY 1
+#endif
+
+#undef MESHCORE_DISPLAY_TOKEN_JOIN
+#undef MESHCORE_DISPLAY_TOKEN_JOIN_INNER
+#undef MESHCORE_NULL_DISPLAY_CLASS_NullDisplayDriver

src/helpers/ui/DisplayDriver.cpp

@@ -0,0 +1,59 @@
+#include "DisplayDriver.h"
+
+#if defined(ESP32_PLATFORM) && defined(MESHCORE_HAS_REAL_DISPLAY)
+
+#include <qrcode.h>
+
+bool DisplayDriver::drawQrCode(const char* text, int x, int y, int size) {
+  if (text == nullptr || text[0] == 0 || x < 0 || y < 0 || size <= 0
+      || size > width() || size > height()
+      || x > width() - size || y > height() - size) {
+    return false;
+  }
+
+  // A 64-pixel square can hold at most Version 9 with the QR-standard
+  // four-module quiet zone. Setup AP payloads are deliberately kept at
+  // Version 1 on small screens so each module is 2x2 physical pixels.
+  static constexpr uint8_t max_version = 9;
+  static constexpr uint8_t max_modules = 4 * max_version + 17;
+  uint8_t modules[(max_modules * max_modules + 7) / 8];
+  QRCode qr = {};
+  bool initialized = false;
+  for (uint8_t version = 1; version <= max_version; ++version) {
+    if (qrcode_initText(&qr, modules, version, ECC_LOW, text) == 0) {
+      initialized = true;
+      break;
+    }
+  }
+  if (!initialized) return false;
+
+  static constexpr int quiet_zone = 4;
+  const int module_size = size / (qr.size + quiet_zone * 2);
+  if (module_size <= 0) return false;
+  const int used_size = module_size * (qr.size + quiet_zone * 2);
+  const int left = x + (size - used_size) / 2;
+  const int top = y + (size - used_size) / 2;
+  const int matrix_left = left + quiet_zone * module_size;
+  const int matrix_top = top + quiet_zone * module_size;
+
+  // Dark-theme OLED/TFT drivers use a dark window and light popup text;
+  // e-paper reverses that convention. Always emit the conventional dark
+  // matrix on a light background instead of relying on scanner inversion.
+  const ColorVal light = isEink() ? UIColor::window_bkg : UIColor::popup_txt;
+  const ColorVal dark = isEink() ? UIColor::primary_txt : UIColor::window_bkg;
+  setColor(light);
+  fillRect(x, y, size, size);
+  setColor(dark);
+  for (uint8_t row = 0; row < qr.size; ++row) {
+    for (uint8_t column = 0; column < qr.size; ++column) {
+      if (qrcode_getModule(&qr, column, row)) {
+        fillRect(matrix_left + column * module_size,
+                 matrix_top + row * module_size,
+                 module_size, module_size);
+      }
+    }
+  }
+  return true;
+}
+
+#endif

src/helpers/ui/DisplayDriver.h

@@ -1,5 +1,7 @@
 #pragma once
 
+#include "DisplayBuildFlags.h"
+
 #include <stdint.h>
 #include <string.h>
 
@@ -70,6 +72,9 @@ public:
   // Optional QR renderer. Coordinates and size use the same logical units as
   // the rest of the UI. Drivers without QR support leave the caller's
   // fallback layout in place.
+#if defined(ESP32_PLATFORM) && defined(MESHCORE_HAS_REAL_DISPLAY)
+  virtual bool drawQrCode(const char* text, int x, int y, int size);
+#else
   virtual bool drawQrCode(const char* text, int x, int y, int size) {
     (void)text;
     (void)x;
@@ -77,6 +82,7 @@ public:
     (void)size;
     return false;
   }
+#endif
   virtual uint16_t getTextWidth(const char* str) = 0;
   virtual bool getTouch(int* x, int* y) {
     (void)x;

src/helpers/ui/WiFiSetupQrDisplay.h

@@ -0,0 +1,45 @@
+#pragma once
+
+#include "DisplayDriver.h"
+#include "WiFiSetupQrPayload.h"
+
+namespace mesh {
+namespace ui {
+
+// Render a setup-AP join QR at the largest size that still leaves the right
+// half of compact displays available for a short textual fallback/reference.
+// Returns false when the payload or panel geometry cannot be represented.
+inline bool drawWiFiSetupQr(DisplayDriver& display, const char* ssid,
+                            const char* address) {
+  char payload[256];
+  const char* password = nullptr;
+#ifdef WEBCONFIG_AP_PASSWORD
+  password = WEBCONFIG_AP_PASSWORD;
+#endif
+  if (!buildWiFiSetupQrPayload(
+          payload, sizeof(payload), ssid, password)) {
+    return false;
+  }
+
+  const int qr_size = display.height() < display.width() / 2
+      ? display.height() : display.width() / 2;
+  if (!display.drawQrCode(payload, 0, 0, qr_size)) return false;
+
+  const int text_x = qr_size + 4;
+  display.setTextSize(1);
+  display.setColor(UIColor::primary_txt);
+  display.setCursor(text_x, 2);
+  display.print("SCAN TO");
+  display.setCursor(text_x, 12);
+  display.print("JOIN:");
+  display.drawTextEllipsized(
+      text_x, 22, display.width() - text_x, ssid);
+  display.setCursor(text_x, 37);
+  display.print("THEN OPEN");
+  display.drawTextEllipsized(
+      text_x, 48, display.width() - text_x, address);
+  return true;
+}
+
+}  // namespace ui
+}  // namespace mesh

src/helpers/ui/WiFiSetupQrPayload.h

@@ -44,7 +44,7 @@ inline bool buildWiFiSetupQrPayload(char* payload, size_t payload_size,
 
   if (!appendWiFiQrText(output, remaining,
                         protected_network ? "WIFI:T:WPA;S:"
-                                          : "WIFI:T:nopass;S:",
+                                          : "WIFI:S:",
                         false)
       || !appendWiFiQrText(output, remaining, ssid, true)) {
     return false;

test/test_display_driver/test_display_driver.cpp

@@ -109,7 +109,14 @@ TEST(WiFiSetupQrPayload, EncodesOpenSetupNetwork) {
   char payload[64];
   EXPECT_TRUE(mesh::ui::buildWiFiSetupQrPayload(
       payload, sizeof(payload), "MC-Set-90DF"));
-  EXPECT_STREQ("WIFI:T:nopass;S:MC-Set-90DF;;", payload);
+  EXPECT_STREQ("WIFI:S:MC-Set-90DF;;", payload);
+
+  char small_payload[32];
+  EXPECT_TRUE(mesh::ui::buildWiFiSetupQrPayload(
+      small_payload, sizeof(small_payload), "MC-90DF"));
+  EXPECT_STREQ("WIFI:S:MC-90DF;;", small_payload);
+  // MC-XXXX uses 16 payload bytes, within QR Version 1-L's 17-byte capacity.
+  EXPECT_LE(strlen(small_payload), 17U);
 }
 
 TEST(WiFiSetupQrPayload, EscapesProtectedNetworkFields) {