Best Friends: C++11 Move Semantics and Pimpl

Move semantics is faster than copy semantics, when the compiler can replace expensive copy operations by cheaper move operations, that is, when it can replace a deep copy of a big object by a shallow copy of the pointer to the big object. Hence, classes using the pimpl idiom in combination with move semantics should see a considerable speed-up. As Qt applies the pimpl idiom consistently to every non-trivial Qt class, we should see a speed-up by simply using Qt classes instead of their STL counterparts. I’ll compare the performance of classes that use move semantics with Qt and STL classes with and without applying the pimpl idiom.
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Performance Gains Through C++11 Move Semantics

We explore when and how our code benefits most from equipping classes with move constructors and assignment operators. We analyse in detail, which constructors and assignment operators (move or copy) are called for C++98 and C++11 when we insert or emplace objects into containers, when we initialise containers and when we shuffle and sort containers. Finally, we run benchmarks for these operations and discuss the actual speed-up, which ranges from 1% to 70%.
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Simplifying Loops with C++11 in Qt Ways

Recently, I looked through the code base of a medium-sized project to see how I could simplify handwritten for-loops by using C++11’s new range-based for and STL algorithms with lambda expressions. The results in short: Range-based for makes loops simpler, easier to understand and often faster. STL algorithms are often a bit harder to read and write than range-based for loops, because lambda expressions are pretty clumsy, algorithm naming is inconsistent, and algorithm interfaces are inconvenient. But, they are still better than handwritten for-loops.
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Remote Support for Harvester Terminal via VNC

The maize harvest is in full swing. The harvester runs nearly 24/7. The driver notices a drop in the area cut per hour. He calls tech support and starts sharing the screen of the terminal in the harvester. The support technician guides guides the driver through changing some machine parameters. All is fine again. My Italian business partner, Ispirata, and I developed a VNC server for the Freescale i.MX53 terminal of Krone’s BiGX forage harvester – to make this scenario possible.
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