Introduction When someone with an OpenGL background begins using Vulkan, one of the very common outcomes - beyond the initial one of "OMG how much code does it take to draw a triangle?" - is that the resulting image is upside down. Searching the web for this will give many hits on discussions about coordinate […]

In a previous blog we demonstrated the most straightforward method to optimize Visual Studio Code for a Qt / C++ environment: simply let the tools do all the work! The example GitHub project we discussed automatically installs both the Microsoft C/C++ and clangd extensions into VS Code. You might wonder why you need both C++ […]

Our colleague Alessandro Ambrosano created a series of blogs (parts 1, 2, and 3) that explain how to get Visual Studio Code configured for Qt development. In that series, Alessandro covers all the details you need to get your VS Code environment configured exactly the way you want it. But there’s a lot there to […]

I'm happy to announce the immediate availability of Heaptrack v1.5.0. Heaptrack is a heap memory profiler targeting mainly Linux, as well as FreeBSD. To learn more, please visit the project website. Version 1.5.0 incorporates about 70 changes since the v1.4.0 release from June last year. The highlights include: - Elfutils is now used for symbolizing […]

KDAB has released GammaRay 3.0.0. GammaRay is a software introspection tool for Qt applications developed by KDAB for internal use, and now shared with the developer community on GitHub. This release is a special one, as we have now added Qt 6 support. An overview of changes since the last release Things we have added […]

When writing large graphics applications in Vulkan or OpenGL, there's many data structures that need to be passed from the CPU to the GPU and vice versa. There are subtle differences in alignment, padding and so on between C++ and GLSL to keep track of as well. I'm going to cover a tool I wrote […]

Reverse engineering in general is a tricky business and sometimes not very orthodox. So, why bother to write this article? Well, sometimes reverse engineering is also for something good. It started when my wife dusted off her watch. We had a huge unpleasant surprise when we found that the companion app is not available anymore […]

Background of Shaders One particular facet of modern graphics development that is often a pain - even for AAA games -- is shader variants! If you have bought an AAA game in recent years and wondered what the heck it is doing when it says it is compiling shaders for a long time (up to […]

The familiar solution for thick value classes that want to preserve binary compatibility is to use the pimpl pattern (private implementation), also known as d-pointer (pointer to data). In future versions of our class, we can freely change the contents of the pimpl (i.e. adding, removing, and/or modifying data members) but the binary compatibility of […]

Not all Qt developers are using Qt Creator as their main IDE for development. Some of us are using other IDEs, like Visual Studio, Visual Studio Code or CLion, per choice or because a project requires it. On Windows, with the MSVC compiler, the debugging experience with Qt 6 can be quite frustrating for some […]

Given a strictly positive integer i, this code will calculate i+1 "equally spaced" values between 1 and 0: If you're looking for a trap, this does actually work for any i > 0. One can verify it experimentally; run the code with i from 1 to INT_MAX. For simplicity, just consider the case j = […]

If you’re a reader of this blog, you probably know that we have a huge amount of quality material on QML and Qt Quick, among other topics. In fact, there is so much material that it can be hard to find what you need. If that sounds familiar, you’ll want to bookmark this page! This […]

This blog will give you a brief overview of profiling C and C++ applications. Additionally, it will lay before you all of the tools available, with the purpose of aiding you in choosing the right tools at the right times. The Steps for Profiling Before we look at the actual tools, let's go over the […]

Hotspot 1.4.0 has been released! Hotspot is a replacement for perf report. It's a GUI for the perf profiler that takes a perf.data file, parses and evaluates its contents, and then displays the result in a graphical way. This feature release contains close to 400 commits since the last stable v1.3.0 release. It comes with […]

Every now and then, when I submit some code for a code review, people tell me that I forgot qAsConst. Now I have one more enemy, namely: Clazy! It has also started saying this, and I guess it's about time for me to figure out what is going on. When do I need qAsConst and […]

In this blog on debugging and profiling, I would like to give you an overview of the debugging tools that exist for C and C++ applications. Automated Testing The first thing you need to do is make sure your code is properly tested. This, in itself, is not debugging, but it enables you to make […]

I will be talking about text in this post, specifically about cases where you have to handle a lot of it. We are not talking about a general solution, but a specific case that we encountered during a customer project. The Problem The project involved showing a chat room for internal communication. We developed a […]

You have two choices when it comes to giving a custom style to your Qt widgets. Qt Style Sheets are very convenient for getting started -- just a few CSS-like rules, and they work. It is our experience, however, that Qt Style Sheets create too much trouble and a QStyle subclass (*) gives a better […]

The nlohmann/json library is everything a developer can expect from a modern library -- easy to integrate and JSON objects are treated as first class citizens with a very intuitive API. However, it has one problem that is widely mentioned across the internet, which I'll tell you about below. Various solutions to the problem have […]

Qt is a high quality library, but it is also massive in number of features. This massive number results in a higher likelihood that there are bugs that go unnoticed lying around in its less frequently used features or combination of features. Our friends at qgis.org hired us to solve some of those issues that […]