Implement simultaneous camera connect (#127)

* Add per-camera task and queue.

Lay the foundation for supporting simultaneous, parallel camera
connections.

The UI now sends commands to the control task, which relays them to
per-camera tasks.
This allows the UI and each connected camera to operate asynchronously.

Increase limit maximum clients from 3 to 8.

* Display human readable mobile device names.

Fix #100 by updating to a development cut of NimBLE-Arduino.
Whilst here improve device bond handling, this makes subsequent
pair/forget sequences a little less iffy.

* Implement multi-connect.

M5ez:
Add context to menu item advanced function.

Furble:
Tweak NimBLE settings.
Remove scan duration, now scan forever as we can stop on demand.
Drop global interval_t, load as needed to reduce variable scope.

Add setting to toggle multi-connect.
Modify connection menu to support tagging cameras.
Add ability to connect to all tagged cameras.

Cannot get directed advertising to mobile devices so still disabled.

Multi-connect to mobile devices is super iffy, not recommended for
production use.

* Tweak the code style a little.

Fix minor error in shutter lock formatting, introduced when migrating
from String to std::string.

Also removed unused macros.

* Update clang-format action version.

* Fix m5stack-core build.

* Minor style updates.

Move some more code into std::string native and const a few more
parameters.

* Further C++ refactoring.

Refactor the Camera type into the base Camera class.
Refactor fillSaveName into CameraList class, it is only used there.
Style adjustments.

.clang-format

@@ -4,3 +4,4 @@ ColumnLimit: 100
 PointerAlignment: Right
 BreakBeforeBinaryOperators: NonAssignment
 SpaceBeforeInheritanceColon: false
+AlignArrayOfStructures: Left

.github/workflows/main.yml

@@ -17,9 +17,9 @@ jobs:
       - uses: actions/checkout@v4
 
       - name: Run clang-format style check
-        uses: jidicula/clang-format-action@v4.11.0
+        uses: jidicula/clang-format-action@v4.13.0
         with:
-          clang-format-version: '13'
+          clang-format-version: '17'
           check-path: '.'
           exclude-regex: 'lib/M5ez/examples'
 

README.md

@@ -7,7 +7,6 @@ cameras.
 
 ![furble - M5StickC-Plus2](https://github.com/user-attachments/assets/e0eebd87-3ac0-4a8b-871a-014eb8c71395)
 
-
 The remote uses the camera's native Bluetooth Low Energy interface so additional
 adapters are not required.
 
@@ -45,6 +44,7 @@ Currently supported features in `furble`:
 - focus
 - GPS location tagging
 - intervalometer
+- multi-connect
 
 ### Table of Features
 
@@ -100,8 +100,10 @@ Connection to mobile devices is a little iffy:
 - hit `Scan`
 - on the mobile device:
    - pair with `furble`
-- on `furble` the mobile device bluetooth MAC address should appear as a connectable target
-   - fixing the target name is tracked in [#100](https://github.com/gkoh/furble/issues/100).
+- on `furble` the mobile device should appear as a connectable target if the pairing was successful
+- connect to the mobile device to save the pairing
+  - the devices will remain paired even if you do not connect and save
+  - forget `furble` on the mobile device to remove such a pair
 
 ### GPS Location Tagging
 
@@ -124,6 +126,25 @@ Delay and shutter time can be figured with custom or preset values from 0 to 999
 
 When in `Shutter` remote control, holding focus (button B) then release (button A) will engage shutter lock, holding the shutter open until a button is pressed.
 
+### Multi-Connect
+
+Multi-Connect enables simultaneous connection to multiple cameras to synchronise
+remote shutter control. Up to 9 (ESP32 hardware limit) cameras can be
+simultaneously controlled.
+
+To use:
+* Pair with one or more cameras
+* Enable `Settings->Multi-Connect`
+* In `Connect` select cameras
+   * Selected cameras will have a `*`
+* Select `Connect *`
+   * Selected cameras will be connected in sequence
+* If all cameras are connected, the standard remote control is shown
+
+WARNING:
+* mobile device connections are extremely finnicky
+* multi-connect involving mobile devices is not well tested and can easily crash
+
 ## Motivation
 
 I found current smartphone apps for basic wireless remote shutter control to be

include/furble_control.h

@@ -4,16 +4,89 @@
 #include <Camera.h>
 
 #define CONTROL_CMD_QUEUE_LEN (32)
+#define TARGET_CMD_QUEUE_LEN (8)
 
 typedef enum {
   CONTROL_CMD_SHUTTER_PRESS,
   CONTROL_CMD_SHUTTER_RELEASE,
   CONTROL_CMD_FOCUS_PRESS,
   CONTROL_CMD_FOCUS_RELEASE,
-  CONTROL_CMD_GPS_UPDATE
+  CONTROL_CMD_GPS_UPDATE,
+  CONTROL_CMD_DISCONNECT,
+  CONTROL_CMD_ERROR
 } control_cmd_t;
 
-void control_update_gps(Furble::Camera::gps_t &gps, Furble::Camera::timesync_t &timesync);
+namespace Furble {
+
+class Control {
+ public:
+  class Target {
+   public:
+    Target(Camera *camera);
+    ~Target();
+
+    Camera *getCamera(void);
+    control_cmd_t getCommand(void);
+    void sendCommand(control_cmd_t cmd);
+    const Camera::gps_t &getGPS(void);
+    const Camera::timesync_t &getTimesync(void);
+
+    void updateGPS(Camera::gps_t &gps, Camera::timesync_t &timesync);
+
+   private:
+    QueueHandle_t m_Queue = NULL;
+    Furble::Camera *m_Camera = NULL;
+    Camera::gps_t m_GPS;
+    Camera::timesync_t m_Timesync;
+  };
+
+  Control(void);
+  ~Control();
+
+  /**
+   * FreeRTOS control task function.
+   */
+  void task(void);
+
+  /**
+   * Send control command to active connections.
+   */
+  BaseType_t sendCommand(control_cmd_t cmd);
+
+  /**
+   * Update GPS and timesync values.
+   */
+  BaseType_t updateGPS(Camera::gps_t &gps, Camera::timesync_t &timesync);
+
+  /**
+   * Are all active cameras still connected?
+   */
+  bool isConnected(void);
+
+  /**
+   * Get list of connected targets.
+   */
+  const std::vector<std::unique_ptr<Control::Target>> &getTargets(void);
+
+  /**
+   * Disconnect all connected cameras.
+   */
+  void disconnect(void);
+
+  /**
+   * Add specified camera to active target list.
+   */
+  void addActive(Camera *camera);
+
+ private:
+  QueueHandle_t m_Queue = NULL;
+  std::vector<std::unique_ptr<Control::Target>> m_Targets;
+};
+
+};  // namespace Furble
+
+extern "C" {
 void control_task(void *param);
+}
 
 #endif

include/furble_gps.h

@@ -1,14 +1,15 @@
 #ifndef FURBLE_GPS_H
 #define FURBLE_GPS_H
 
-#include <Camera.h>
 #include <TinyGPS++.h>
 
+#include "furble_control.h"
+
 extern TinyGPSPlus furble_gps;
 
 extern bool furble_gps_enable;
 
 void furble_gps_init(void);
-void furble_gps_update(Furble::Camera *camera);
+void furble_gps_update(Furble::Control *control);
 
 #endif

include/furble_ui.h

@@ -1,10 +1,10 @@
 #ifndef FURBLE_UI_H
 #define FURBLE_UI_H
 
-#include <Camera.h>
+#include "furble_control.h"
 
 struct FurbleCtx {
-  Furble::Camera *camera;
+  Furble::Control *control;
   bool reconnected;
 };
 

include/settings.h

@@ -6,8 +6,6 @@
 
 #include "interval.h"
 
-extern interval_t interval;
-
 void settings_menu_tx_power(void);
 esp_power_level_t settings_load_esp_tx_power(void);
 
@@ -17,7 +15,10 @@ void settings_menu_gps(void);
 void settings_load_interval(interval_t *interval);
 void settings_save_interval(interval_t *interval);
 
-void settings_add_interval_items(ezMenu *submenu);
+void settings_add_interval_items(ezMenu *submenu, interval_t *interval);
 void settings_menu_interval(void);
 
+bool settings_load_multiconnect(void);
+void settings_save_multiconnect(bool multiconnect);
+
 #endif

include/spinner.h

@@ -16,8 +16,8 @@ struct __attribute__((packed)) SpinValue {
 
 void spinner_modify_value(const char *title, bool preset, SpinValue *sv);
 
-std::string sv2str(SpinValue *sv);
-unsigned long sv2ms(SpinValue *sv);
+std::string sv2str(const SpinValue *sv);
+unsigned long sv2ms(const SpinValue *sv);
 void ms2hms(unsigned long ms, unsigned int *h, unsigned int *m, unsigned int *s);
 
 #endif

lib/M5ez/src/M5ez.cpp

@@ -450,7 +450,7 @@ size_t ezCanvas::write(const uint8_t *buffer, size_t size) {
   return size;
 }
 
-uint16_t ezCanvas::loop(void *private_data) {
+uint16_t ezCanvas::loop(void *context) {
   if (_next_scroll && millis() >= _next_scroll) {
     ez.setFont(_font);
     uint8_t h = ez.fontHeight();
@@ -907,7 +907,7 @@ void changeCpuPower(bool reduce) {
   }
 }
 
-uint16_t ezBacklight::loop(void *private_data) {
+uint16_t ezBacklight::loop(void *context) {
   if (!_backlight_off && _inactivity) {
     if (millis() > _last_activity + 30000 * _inactivity) {
       _backlight_off = true;
@@ -955,7 +955,7 @@ void ezBattery::begin() {
   }
 }
 
-uint16_t ezBattery::loop(void *private_data) {
+uint16_t ezBattery::loop(void *context) {
   if (!_on)
     return 0;
   ez.header.draw("battery");
@@ -1059,11 +1059,12 @@ void M5ez::begin() {
 }
 
 void M5ez::yield() {
-  ::yield();  // execute the Arduino yield in the root namespace
+  vTaskDelay(1);  // allow lower priority tasks to run
+  ::yield();      // execute the Arduino yield in the root namespace
   M5.update();
   for (uint8_t n = 0; n < _events.size(); n++) {
     if (millis() > _events[n].when) {
-      uint16_t r = (_events[n].function)(_events[n].private_data);
+      uint16_t r = (_events[n].function)(_events[n].context);
       if (r) {
         _events[n].when = millis() + r - 1;
       } else {
@@ -1074,17 +1075,15 @@ void M5ez::yield() {
   }
 }
 
-void M5ez::addEvent(uint16_t (*function)(void *private_data),
-                    void *private_data,
-                    uint32_t when /* = 1 */) {
+void M5ez::addEvent(uint16_t (*function)(void *context), void *context, uint32_t when /* = 1 */) {
   event_t n;
   n.function = function;
-  n.private_data = private_data;
+  n.context = context;
   n.when = millis() + when - 1;
   _events.push_back(n);
 }
 
-void M5ez::removeEvent(uint16_t (*function)(void *private_data)) {
+void M5ez::removeEvent(uint16_t (*function)(void *context)) {
   uint8_t n = 0;
   while (n < _events.size()) {
     if (_events[n].function == function) {
@@ -1274,13 +1273,14 @@ void ezMenu::txtFont(const GFXfont *font) {
 bool ezMenu::addItem(std::string name,
                      std::string caption,
                      void (*simpleFunction)() /* = NULL */,
-                     bool (*advancedFunction)(ezMenu *callingMenu) /* = NULL */,
+                     void *context /* = NULL */,
+                     bool (*advancedFunction)(ezMenu *callingMenu, void *context) /* = NULL */,
                      void (*drawFunction)(ezMenu *callingMenu,
                                           int16_t x,
                                           int16_t y,
                                           int16_t w,
                                           int16_t h) /* = NULL */) {
-  MenuItem_t new_item = {name, caption, simpleFunction, advancedFunction, drawFunction};
+  MenuItem_t new_item = {name, caption, context, simpleFunction, advancedFunction, drawFunction};
   if (_selected == -1)
     _selected = _items.size();
   _items.push_back(new_item);
@@ -1437,7 +1437,7 @@ int16_t ezMenu::_runTextOnce(bool dynamic) {
         (_items[_selected].simpleFunction)();
       }
       if (_items[_selected].advancedFunction) {
-        if (!(_items[_selected].advancedFunction)(this))
+        if (!(_items[_selected].advancedFunction)(this, _items[_selected].context))
           return 0;
       }
       return _selected

lib/M5ez/src/M5ez.h

@@ -233,7 +233,7 @@ class ezCanvas: public Print {
       uint8_t c);  // These three are used to inherit print and println from Print class
   virtual size_t write(const char *str);
   virtual size_t write(const uint8_t *buffer, size_t size);
-  static uint16_t loop(void *private_data);
+  static uint16_t loop(void *context);
 
  private:
   static ezTFT tft;
@@ -297,7 +297,8 @@ class ezMenu {
       std::string name,
       std::string caption = "",
       void (*simpleFunction)() = NULL,
-      bool (*advancedFunction)(ezMenu *callingMenu) = NULL,
+      void *context = nullptr,
+      bool (*advancedFunction)(ezMenu *callingMenu, void *context) = NULL,
       void (*drawFunction)(ezMenu *callingMenu, int16_t x, int16_t y, int16_t w, int16_t h) = NULL);
   bool deleteItem(int16_t index);
   bool deleteItem(std::string name);
@@ -338,8 +339,9 @@ class ezMenu {
   struct MenuItem_t {
     std::string name;
     std::string caption;
+    void *context;
     void (*simpleFunction)();
-    bool (*advancedFunction)(ezMenu *callingMenu);
+    bool (*advancedFunction)(ezMenu *callingMenu, void *context);
     void (*drawFunction)(ezMenu *callingMenu, int16_t x, int16_t y, int16_t w, int16_t h);
   };
   std::vector<MenuItem_t> _items;
@@ -425,7 +427,7 @@ class ezBacklight {
   static void menu();
   static void inactivity(uint8_t half_minutes);
   static void activity();
-  static uint16_t loop(void *private_data);
+  static uint16_t loop(void *context);
 
  private:
   static uint8_t _brightness;
@@ -450,7 +452,7 @@ class ezBacklight {
 class ezBattery {
  public:
   static void begin();
-  static uint16_t loop(void *private_data);
+  static uint16_t loop(void *context);
   static uint8_t getTransformedBatteryLevel();
   static uint16_t getBatteryBarColor(uint8_t batteryLevel);
 
@@ -471,7 +473,7 @@ class ezBattery {
 
 struct event_t {
   uint16_t (*function)(void *);
-  void *private_data;
+  void *context;
   uint32_t when;
 };
 
@@ -503,10 +505,8 @@ class M5ez {
 
   static void yield();
 
-  static void addEvent(uint16_t (*function)(void *),
-                       void *private_data = nullptr,
-                       uint32_t when = 1);
-  static void removeEvent(uint16_t (*function)(void *private_data));
+  static void addEvent(uint16_t (*function)(void *), void *context = nullptr, uint32_t when = 1);
+  static void removeEvent(uint16_t (*function)(void *context));
   static void redraw();
 
   // ez.msgBox