gui, tracker/{aruco,pt}, api: detect whether widget is visible on screen

Sadly, it's only implemented right now on win32.

Remove "set enabled" code for the video widget since it only works for
explicit window minimization, not covering by other windows.

1 files changed, 22 insertions, 7 deletions

diff --git a/tracker-pt/pt_video_widget.cpp b/tracker-pt/pt_video_widget.cpp
index 99f86eb2..38d7a5e8 100644
--- a/tracker-pt/pt_video_widget.cpp
+++ b/tracker-pt/pt_video_widget.cpp
@@ -1,20 +1,28 @@
 /* Copyright (c) 2012 Patrick Ruoff
- * Copyright (c) 2015 Stanislaw Halik <sthalik@misaki.pl>
+ * Copyright (c) 2014-2016 Stanislaw Halik <sthalik@misaki.pl>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
- *
- * 20130312, WVR: Add 7 lines to resizeGL after resize_frame. This should lower CPU-load.
  */
 
 #include "pt_video_widget.h"
 #include <opencv2/imgproc.hpp>
 
+#include "opentrack/is-window-visible.hpp"
+
+PTVideoWidget::PTVideoWidget(QWidget* parent) :
+    QWidget(parent),
+    freshp(false)
+{
+    connect(&timer, SIGNAL(timeout()), this, SLOT(update_and_repaint()));
+    timer.start(50);
+}
+
 void PTVideoWidget::update_image(const cv::Mat& frame)
 {
     QMutexLocker foo(&mtx);
-    
+
     if (!freshp)
     {
         if (_frame.cols != frame.cols || _frame.rows != frame.rows)
@@ -27,20 +35,27 @@ void PTVideoWidget::update_image(const cv::Mat& frame)
     }
 }
 
+void PTVideoWidget::paintEvent(QPaintEvent* e)
+{
+    QMutexLocker foo(&mtx);
+    QPainter painter(this);
+    painter.drawImage(e->rect(), texture);
+}
+
 void PTVideoWidget::update_and_repaint()
 {
-    if (static_cast<QWidget*>(parent())->isEnabled())
+    if (is_window_visible(this))
     {
         QMutexLocker foo(&mtx);
         if (_frame.empty() || !freshp)
             return;
         cv::cvtColor(_frame, _frame2, cv::COLOR_RGB2BGR);
-        
+
         if (_frame3.cols != width() || _frame3.rows != height())
             _frame3 = cv::Mat(height(), width(), CV_8U);
 
         cv::resize(_frame2, _frame3, cv::Size(width(), height()), 0, 0, cv::INTER_NEAREST);
-        
+
         texture = QImage((const unsigned char*) _frame3.data, _frame3.cols, _frame3.rows, QImage::Format_RGB888);
         freshp = false;
         update();