tracker/pt: simplify pointless inheritance

3 files changed, 79 insertions, 105 deletions

diff --git a/tracker-pt/camera.cpp b/tracker-pt/camera.cpp
index 82f4a6fe..435348b1 100644
--- a/tracker-pt/camera.cpp
+++ b/tracker-pt/camera.cpp
@@ -10,7 +10,10 @@
 #include <string>
 #include <QDebug>
 
-Camera::~Camera() {}
+Camera::~Camera()
+{
+    stop();
+}
 
 void Camera::set_device(const QString& name)
 {
@@ -18,15 +21,14 @@ void Camera::set_device(const QString& name)
 
     desired_name = name;
 
-    if (desired_index != index)
+    if (index != cam_desired.idx || desired_name != active_name)
     {
-        desired_index = index;
-        _set_device_index();
+        stop();
+        cam_desired.idx = index;
 
         // reset fps
         dt_valid = 0;
         dt_mean = 0;
-        active_index = index;
     }
 }
 
@@ -35,12 +37,18 @@ QString Camera::get_desired_name() const
     return desired_name;
 }
 
+QString Camera::get_active_name() const
+{
+    return active_name;
+}
+
 void Camera::set_fps(int fps)
 {
     if (cam_desired.fps != fps)
     {
         cam_desired.fps = fps;
-        _set_fps();
+        if (cap)
+            cap->set(cv::CAP_PROP_FPS, cam_desired.fps);
     }
 }
 
@@ -50,16 +58,18 @@ void Camera::set_res(int x_res, int y_res)
     {
         cam_desired.res_x = x_res;
         cam_desired.res_y = y_res;
-        _set_res();
+        if (cap)
+        {
+            cap->set(cv::CAP_PROP_FRAME_WIDTH,  cam_desired.res_x);
+            cap->set(cv::CAP_PROP_FRAME_HEIGHT, cam_desired.res_y);
+        }
     }
 }
 
 DEFUN_WARN_UNUSED bool Camera::get_info(CamInfo& ret)
 {
     if (cam_info.res_x == 0 || cam_info.res_y == 0)
-    {
         return false;
-    }
     ret = cam_info;
     return true;
 }
@@ -68,7 +78,7 @@ bool Camera::get_frame(double dt, cv::Mat* frame)
 {
     bool new_frame = _get_frame(frame);
     // measure fps of valid frames
-    static constexpr double RC = 1; // second
+    static constexpr double RC = 1; // seconds
     const double alpha = dt/(dt + RC);
     dt_valid += dt;
     if (new_frame)
@@ -85,40 +95,33 @@ bool Camera::get_frame(double dt, cv::Mat* frame)
     return new_frame;
 }
 
-void CVCamera::start()
+void Camera::start()
 {
-    stop();
-    cap = new cv::VideoCapture(desired_index);
-    _set_res();
-    _set_fps();
-    // extract camera info
+    cap = camera_ptr(new cv::VideoCapture(cam_desired.idx));
+
+    set_res(cam_desired.res_x, cam_desired.res_y);
+    set_fps(cam_desired.fps);
+
     if (cap->isOpened())
     {
-        active_index = desired_index;
+        cam_info.idx = cam_desired.idx;
         cam_info.res_x = 0;
         cam_info.res_y = 0;
-    } else {
-        stop();
+        active_name = desired_name;
     }
+    else
+        stop();
 }
 
-void CVCamera::stop()
+void Camera::stop()
 {
-    if (cap)
-    {
-        const bool opened = cap->isOpened();
-        if (opened)
-        {
-            qDebug() << "pt: freeing camera";
-            cap->release();
-        }
-        delete cap;
-        cap = nullptr;
-        qDebug() << "pt camera: stopped";
-    }
+    cap = nullptr;
+    desired_name = QString();
+    active_name = QString();
+    cam_info = CamInfo();
 }
 
-bool CVCamera::_get_frame(cv::Mat* frame)
+bool Camera::_get_frame(cv::Mat* frame)
 {
     if (cap && cap->isOpened())
     {
@@ -134,22 +137,3 @@ bool CVCamera::_get_frame(cv::Mat* frame)
     }
     return false;
 }
-
-void CVCamera::_set_fps()
-{
-    if (cap) cap->set(cv::CAP_PROP_FPS, cam_desired.fps);
-}
-
-void CVCamera::_set_res()
-{
-    if (cap)
-    {
-        cap->set(cv::CAP_PROP_FRAME_WIDTH,  cam_desired.res_x);
-        cap->set(cv::CAP_PROP_FRAME_HEIGHT, cam_desired.res_y);
-    }
-}
-void CVCamera::_set_device_index()
-{
-    if (desired_index != active_index)
-        stop();
-}
diff --git a/tracker-pt/camera.h b/tracker-pt/camera.h
index be7d35c4..75c5faa4 100644
--- a/tracker-pt/camera.h
+++ b/tracker-pt/camera.h
@@ -17,24 +17,22 @@
 
 struct CamInfo
 {
-    CamInfo() : res_x(0), res_y(0), fps(0) {}
+    CamInfo() : res_x(0), res_y(0), fps(0), idx(-1) {}
 
     int res_x;
     int res_y;
     int fps;
+    int idx;
 };
 
-// ----------------------------------------------------------------------------
-// Base class for cameras, calculates the frame rate
-class Camera
+class Camera final
 {
 public:
-        Camera() : dt_valid(0), dt_mean(0), desired_index(0), active_index(-1) {}
-        virtual ~Camera() = 0;
+        Camera() : dt_valid(0), dt_mean(0) {}
+        ~Camera();
 
-        // start/stop capturing
-        virtual void start() = 0;
-        virtual void stop() = 0;
+        void start();
+        void stop();
         void restart() { stop(); start(); }
 
         // calls corresponding template methods and reinitializes frame rate calculation
@@ -42,56 +40,44 @@ public:
         void set_fps(int fps);
         void set_res(int x_res, int y_res);
 
-        // gets a frame from the camera, dt: time since last call in seconds
         DEFUN_WARN_UNUSED bool get_frame(double dt, cv::Mat* frame);
-
-        // WARNING: returned references are valid as long as object
         DEFUN_WARN_UNUSED bool get_info(CamInfo &ret);
+
         CamInfo get_desired() const { return cam_desired; }
         QString get_desired_name() const;
-protected:
-        // get a frame from the camera
-        DEFUN_WARN_UNUSED virtual bool _get_frame(cv::Mat* frame) = 0;
-
-        // update the camera using cam_desired, write res and f to cam_info if successful
-        virtual void _set_device_index() = 0;
-        virtual void _set_fps() = 0;
-        virtual void _set_res() = 0;
+        QString get_active_name() const;
+
+        cv::VideoCapture& operator*() { return *cap; }
+        const cv::VideoCapture& operator*() const { return *cap; }
+        cv::VideoCapture* operator->() { return cap.get(); }
+        const cv::VideoCapture* operator->() const { return cap.get(); }
+        operator bool() const { return cap && cap->isOpened(); }
+
 private:
+        DEFUN_WARN_UNUSED bool _get_frame(cv::Mat* frame);
+
         double dt_valid;
         double dt_mean;
-protected:
+
         CamInfo cam_info;
         CamInfo cam_desired;
-        QString desired_name;
-        int desired_index;
-        int active_index;
-};
+        QString desired_name, active_name;
 
-// ----------------------------------------------------------------------------
-// camera based on OpenCV's videoCapture
-class CVCamera final : public Camera
-{
-public:
-    CVCamera() : cap(NULL) {}
-    ~CVCamera() { stop(); }
-
-    void start() override;
-    void stop() override;
-
-    operator cv::VideoCapture*() { return cap; }
-protected:
-    bool _get_frame(cv::Mat* frame) override;
-    void _set_fps() override;
-    void _set_res() override;
-    void _set_device_index() override;
-private:
-    cv::VideoCapture* cap;
-};
+        struct camera_deleter final
+        {
+            void operator()(cv::VideoCapture* cap)
+            {
+                if (cap)
+                {
+                    if (cap->isOpened())
+                        cap->release();
+                    static const std::default_delete<cv::VideoCapture> deleter;
+                    deleter(cap);
+                }
+            }
+        };
 
-enum RotationType
-{
-    CLOCKWISE = 0,
-    ZERO = 1,
-    COUNTER_CLOCKWISE = 2
+        using camera_ptr = std::unique_ptr<cv::VideoCapture, camera_deleter>;
+
+        std::unique_ptr<cv::VideoCapture, camera_deleter> cap;
 };
diff --git a/tracker-pt/ftnoir_tracker_pt_dialog.cpp b/tracker-pt/ftnoir_tracker_pt_dialog.cpp
index 749ea1ff..d3951bd9 100644
--- a/tracker-pt/ftnoir_tracker_pt_dialog.cpp
+++ b/tracker-pt/ftnoir_tracker_pt_dialog.cpp
@@ -142,12 +142,16 @@ void TrackerDialog_PT::set_camera_settings_available(const QString& camera_name)
 void TrackerDialog_PT::show_camera_settings()
 {
     const int idx = ui.camdevice_combo->currentIndex();
+
     if (tracker)
     {
-        cv::VideoCapture* cap = tracker->camera;
-        if (cap && cap->isOpened())
+        if (tracker->camera)
         {
-            video_property_page::show_from_capture(*cap, idx);
+            cv::VideoCapture& cap = *tracker->camera;
+
+            CamInfo info;
+            if (tracker->camera.get_info(info))
+                video_property_page::show_from_capture(cap, info.idx);
         }
     }
     else