refactoring, renaming and commenting

modules/viz2d/include/opencv2/viz2d/util.hpp

@@ -53,7 +53,7 @@ CV_EXPORTS void print_system_info();
  * using #install_signal_handlers()
  * @return true if the program should keep on running
  */
-CV_EXPORTS bool keep_running();
+CV_EXPORTS bool keepRunning();
 
 /*!
  * Little helper function to keep track of FPS and optionally display it using NanoVG

modules/viz2d/include/opencv2/viz2d/viz2d.hpp

@@ -149,7 +149,7 @@ public:
      * @param samples MSAA samples.
      * @param debug Create a debug OpenGL context.
      */
-    CV_EXPORTS Viz2D(const cv::Size& initialSize, const cv::Size& frameBufferSize, bool offscreen,
+    CV_EXPORTS static cv::Ptr<Viz2D> make(const cv::Size& initialSize, const cv::Size& frameBufferSize, bool offscreen,
             const string& title, int major = 4, int minor = 6, int samples = 0, bool debug = false);
     /*!
      * Default destructor
@@ -386,6 +386,19 @@ public:
      */
     CV_EXPORTS bool display();
 private:
+    /*!
+     * Creates a Viz2D object which is the central object to perform visualizations with.
+     * @param initialSize The initial size of the heavy-weight window.
+     * @param frameBufferSize The initial size of the framebuffer backing the window (needs to be equal or greate then initial size).
+     * @param offscreen Don't create a window and rather render offscreen.
+     * @param title The window title.
+     * @param major The OpenGL major version to request.
+     * @param minor The OpenGL minor version to request.
+     * @param samples MSAA samples.
+     * @param debug Create a debug OpenGL context.
+     */
+    CV_EXPORTS Viz2D(const cv::Size& initialSize, const cv::Size& frameBufferSize, bool offscreen,
+            const string& title, int major = 4, int minor = 6, int samples = 0, bool debug = false);
     void setDefaultKeyboardEventCallback();
     void setKeyboardEventCallback(
             std::function<bool(int key, int scancode, int action, int modifiers)> fn);

modules/viz2d/samples/cpp/beauty/beauty-demo.cpp

@@ -48,7 +48,7 @@ bool side_by_side = false;
 bool stretch = false;
 #endif
 
-static cv::Ptr<cv::viz::Viz2D> v2d = new cv::viz::Viz2D(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Beauty Demo");
+static cv::Ptr<cv::viz::Viz2D> v2d = cv::viz::Viz2D::make(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Beauty Demo");
 static cv::Ptr<cv::face::Facemark> facemark = cv::face::createFacemarkLBF();
 #ifdef USE_TRACKER
 static cv::Ptr<cv::Tracker> tracker = cv::TrackerKCF::create();
@@ -391,7 +391,7 @@ int main(int argc, char **argv) {
     Sink sink = make_writer_sink(OUTPUT_FILENAME, cv::VideoWriter::fourcc('V', 'P', '9', '0'), src.fps(), cv::Size(WIDTH, HEIGHT));
     v2d->setSink(sink);
 
-    while (keep_running())
+    while (keepRunning())
         iteration();
 #else
     Source src = make_capture_source(WIDTH, HEIGHT);

modules/viz2d/samples/cpp/font/font-demo.cpp

@@ -46,7 +46,7 @@ using std::string;
 using std::vector;
 using std::istringstream;
 
-cv::Ptr<cv::viz::Viz2D> v2d = new cv::viz::Viz2D(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Font Demo");
+cv::Ptr<cv::viz::Viz2D> v2d = cv::viz::Viz2D::make(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Font Demo");
 vector<string> lines;
 bool update_stars = true;
 bool update_perspective = true;
@@ -225,7 +225,7 @@ int main(int argc, char **argv) {
 #ifndef __EMSCRIPTEN__
     Sink sink = make_writer_sink(OUTPUT_FILENAME, cv::VideoWriter::fourcc('V', 'P', '9', '0'), FPS, cv::Size(WIDTH, HEIGHT));
     v2d->setSink(sink);
-    while(keep_running())
+    while(keepRunning())
         iteration();
 #else
     emscripten_set_main_loop(iteration, -1, true);

modules/viz2d/samples/cpp/nanovg/nanovg-demo.cpp

@@ -124,7 +124,7 @@ int main(int argc, char **argv) {
         exit(1);
     }
 
-    cv::Ptr<Viz2D> v2d = new Viz2D(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "NanoVG Demo");
+    cv::Ptr<Viz2D> v2d = Viz2D::make(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "NanoVG Demo");
     print_system_info();
     if (!v2d->isOffscreen())
         v2d->setVisible(true);

modules/viz2d/samples/cpp/optflow/optflow-demo.cpp

@@ -47,9 +47,9 @@ const unsigned long DIAG = hypot(double(WIDTH), double(HEIGHT));
 constexpr const char* OUTPUT_FILENAME = "optflow-demo.mkv";
 constexpr bool OFFSCREEN = false;
 
-static cv::Ptr<cv::viz::Viz2D> v2d = new cv::viz::Viz2D(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Sparse Optical Flow Demo");
+static cv::Ptr<cv::viz::Viz2D> v2d = cv::viz::Viz2D::make(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Sparse Optical Flow Demo");
 #ifndef __EMSCRIPTEN__
-static cv::Ptr<cv::viz::Viz2D> v2dMenu = new cv::viz::Viz2D(cv::Size(240, 360), cv::Size(240,360), false, "Display Settings");
+static cv::Ptr<cv::viz::Viz2D> v2dMenu = cv::viz::Viz2D::make(cv::Size(240, 360), cv::Size(240,360), false, "Display Settings");
 #endif
 
 /** Visualization parameters **/
@@ -491,7 +491,7 @@ int main(int argc, char **argv) {
     Sink sink = make_writer_sink(OUTPUT_FILENAME, cv::VideoWriter::fourcc('V', 'P', '9', '0'), src.fps(), cv::Size(WIDTH, HEIGHT));
     v2d->setSink(sink);
 
-    while (keep_running())
+    while (keepRunning())
         iteration();
 #else
     Source src = make_capture_source(WIDTH, HEIGHT);

modules/viz2d/samples/cpp/pedestrian/pedestrian-demo.cpp

@@ -115,7 +115,7 @@ int main(int argc, char **argv) {
         exit(1);
     }
 
-    cv::Ptr<Viz2D> v2d = new Viz2D(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Beauty Demo");
+    cv::Ptr<Viz2D> v2d = Viz2D::make(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Beauty Demo");
     print_system_info();
     if (!v2d->isOffscreen())
         v2d->setVisible(true);
@@ -145,7 +145,7 @@ int main(int argc, char **argv) {
     cv::Rect lastTracked(0,0,1,1);
 
     bool redetect = true;
-    while (keep_running()) {
+    while (keepRunning()) {
         if(!v2d->capture())
             break;
 

modules/viz2d/samples/cpp/shader/shader-demo.cpp

@@ -322,7 +322,7 @@ void glow_effect(const cv::UMat &src, cv::UMat &dst, const int ksize) {
     cv::bitwise_not(dst, dst);
 }
 
-cv::Ptr<cv::viz::Viz2D> v2d = new cv::viz::Viz2D(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Shader Demo");
+cv::Ptr<cv::viz::Viz2D> v2d = cv::viz::Viz2D::make(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Shader Demo");
 
 void setup_gui(cv::Ptr<cv::viz::Viz2D> v2d) {
     v2d->nanogui([](cv::viz::FormHelper& form){
@@ -437,7 +437,7 @@ int main(int argc, char **argv) {
         Sink sink = make_writer_sink(OUTPUT_FILENAME, cv::VideoWriter::fourcc('V', 'P', '9', '0'), FPS, cv::Size(WIDTH, HEIGHT));
         v2d->setSink(sink);
 
-        while(keep_running())
+        while(keepRunning())
             iteration();
 #else
         Source src = make_capture_source(WIDTH, HEIGHT);

modules/viz2d/samples/cpp/tetra/tetra-demo.cpp

@@ -89,7 +89,7 @@ void glow_effect(const cv::UMat &src, cv::UMat &dst, const int ksize) {
 int main(int argc, char **argv) {
     using namespace cv::viz;
 
-    cv::Ptr<Viz2D> v2d = new Viz2D(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Tetra Demo");
+    cv::Ptr<Viz2D> v2d = Viz2D::make(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Tetra Demo");
     print_system_info();
     if(!v2d->isOffscreen())
         v2d->setVisible(true);
@@ -99,7 +99,7 @@ int main(int argc, char **argv) {
 
     v2d->gl(init_scene);
 
-    while (keep_running()) {
+    while (keepRunning()) {
         //Render using OpenGL
         v2d->gl(render_scene);
 

modules/viz2d/samples/cpp/video/video-demo.cpp

@@ -93,7 +93,7 @@ int main(int argc, char **argv) {
         cerr << "Usage: video-demo <video-file>" << endl;
         exit(1);
     }
-    cv::Ptr<Viz2D> v2d = new Viz2D(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Video Demo");
+    cv::Ptr<Viz2D> v2d = Viz2D::make(cv::Size(WIDTH, HEIGHT), cv::Size(WIDTH, HEIGHT), OFFSCREEN, "Video Demo");
     print_system_info();
     if(!v2d->isOffscreen())
         v2d->setVisible(true);
@@ -106,7 +106,7 @@ int main(int argc, char **argv) {
 
     v2d->gl(init_scene);
 
-    while (keep_running()) {
+    while (keepRunning()) {
         if(!v2d->capture())
             break;
 

modules/viz2d/src/util.cpp

@@ -125,7 +125,7 @@ static void install_signal_handlers() {
     signal(SIGTERM, request_finish);
 }
 
-bool keep_running() {
+bool keepRunning() {
     if (!signal_handlers_installed) {
         install_signal_handlers();
     }

modules/viz2d/src/viz2d.cpp

@@ -47,6 +47,11 @@ cv::Scalar colorConvert(const cv::Scalar& src, cv::ColorConversionCodes code) {
     return dst;
 }
 
+cv::Ptr<Viz2D> Viz2D::make(const cv::Size& initialSize, const cv::Size& frameBufferSize, bool offscreen,
+            const string& title, int major, int minor, int samples, bool debug) {
+    return new Viz2D(initialSize, frameBufferSize, offscreen, title, major, minor, samples, debug);
+}
+
 Viz2D::Viz2D(const cv::Size& size, const cv::Size& frameBufferSize, bool offscreen,
         const string& title, int major, int minor, int samples, bool debug) :
         initialSize_(size), frameBufferSize_(frameBufferSize), viewport_(0, 0,