Machine Learning • Deep Learning • Programming
When we use OpenCV from command line process, sometimes OpenCV will print internal logging messages such as: This might be useful while debugging OpenCV problems but it is a noise if we want to print our own messages to the console. In this case, it is desirable to disable the internal OpenCV logging using the …
Qt comes with a QTreeWidget class which can be used to show data in a tree view. It can be used to show hierarchical data using either Model/View framework or by manually creating the hierarchy. The QTreeWidget supports multi-columns for each row and also allows editing of the individual cells. However, sometimes we need to …
SLogLib is a flexible logging library written in C++. It comes with three logging devices: console, file, and memory but often there is a need to show log directly on the user interface. I heavily use Qt for all projects requiring user interface, so I wrote a logging device for QWidget. It is available in …
Recently, I worked on a project which made heavy use of C++ threads. To use SLogLib in this project I added multi-threaded support in SLogLib with the help of c++ 11 std::mutex and std::lock_guard. Over the last few months multi-threaded support in SLogLib has been extensively tested and there are no known bugs. All threading …
Some time back, I developed a data entry application in Qt5. One of the requirements was to let the user select a single string from a predefined list of string. I developed a custom widget called SStringSelector for this purpose. SStringSelector has two views: display and selection. The display view presents the currently selected string …
Qt5 support standard dialogs such as QFileDialog, QFontDialog, and QColorDialog, however, it does not provide a color picker to allow a user to pick a color. Recently, I need a color picker for one of my projects and I implemented a simple color picker widget. SColorPicker is available from Github as a part of QtUtils …
This week, at work I had to implement a search box for a software I am working on. The search box is to filter some data dynamically as user types a query. I wanted to show a clear (cross) icon at the right side of the search box so that user can clear the results instead …
Often there is a need to estimate the time it takes for a piece of code to run. This is useful not only for debugging but also for reporting the execution time of lengthy tasks to the user. On Windows, QueryPerformanceFrequency() and QueryPerformanceCounter() can be used to determine the execution time of a code. QueryPerformanceFrequency() …
A long time ago when I was doing PhD I was implementing a very complex geometric algorithm for computing intersection of two triangular meshes. There were bugs in code which would trigger only in certain edge cases. Since it was a GUI program using std::cout was not an option. Initially I tried writing messages to …
In this post I will show how to compute area of a facet in CGAL::Polyhedron_3. ComputeFacetArea() Functor ComputeFacetArea() is a thread-safe functor for computing the area of a given facet in a CGAL::Polyhedron_3. The facet must be a planar polygon with arbitrary number of sides. We need facet’s normal vector to compute it’s area. The …