MArek Krajewski - Hands‑On High Performance Programming with Qt 5

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First edition: January 2019

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ISBN 978-1-78953-124-4

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Marek Krajewski

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MarekKrajewski has been programming in C++ since the mid 90s, and in Qt since 2008. In his career, he has been involved with Unix and Windows system programming, client-server systems, UMTS network management, Enterprise Java, satellite protocol decoding, neural networks, image processing, DVB-T testing appliances, REST APIs, and embedded Linux. He holds a Ph.D. in computer science and is currently working as an independent programmer specializing in Qt, C++, GUIs, system programming, and communication protocols. His other interests are off-piste skiing and Aikido, where he holds the rank of second dan.

Nibedit Dey is a techno- entrepreneur and innovator with over 8 years of experience in building complex software-based products using Qt and C++. Before starting his entrepreneurial journey, he worked for L&T and Tektronix in different research and development roles. Additionally, he has reviewed The Modern C++ Challenge and Hands-on GUI programming with C++ and Qt5 books for Packt.

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In today's world, programming knowledge appears to be scattered over a myriad of locationsblog posts, Wikipedia articles, conference presentations, Twitter threads, Stack Overflow questions, and the odd scientific paper to boot. Because of that, I was quite glad when the publishers approached me with an idea for a book about Qt performanceat last, a single place where program performance knowledge could be collected.

This book will try to give you an overview of program performance optimization techniques and apply them in the context of Qt programming. Qt is a cross-platform and cross-topic programming framework encompassing both GUI and system programming on desktop, mobile, and embedded platforms. Hence, while discussing Qt's performance, we will encounter a broad gamut of performance topics of every shade and color, and we will do this not in an abstract manner, but using real-life examples.

Since Qt has many different versions and releases, we will concentrate on the current (as of the time of writing) long-term support (LTS) version, namely, Qt 5.9, but will also provide information regarding later Qt versions up to Qt 5.12. Fitting the high-performance theme, we will mostly be using the epitome of high performance, that is Qt's underlying C++ language, directly.

Moreover, in order to make this book approachable, we will use open source development tools and a very widespread and relatively recent OS platform, namely, Microsoft Windows 10.

I wanted to write a book that I would enjoy reading when I first started to learn about performance years agowe will start slowly, but then go deep, as I hope to provide you with most of the knowledge required to write performant Qt programs.

This book is intended for developers who wish to build highly performant Qt applications for desktop and embedded devices using the C++ language. If you'd like to optimize the performance of a Qt application that has already been written , you could also find this book useful.