Dugi – Lords Of Tech

C++20 Resumable functions: Goodbye state machines, no one will mourn you

C++20 allows writing functions that suspend and can continue at the next line. This has an amazing application at avoiding writing annoying and error-prone state machines. This article showcases how coroutines can clean up a function that would usually need an ugly state machine.

Error codes are far slower than exceptions

TL;DR On modern 64-bit PC architectures, C++ exceptions only add unreachable code with destructor calls into functions and their effect on performance is below 1%, but such low values are difficult to measure. Handling rare errors with return values requires additional branching that slows down the program in realistic scenarios by about 5% and are also less convenient. If an exception is actually thrown, stack unwinding costs about 2 µs per stack frame.

(Sort of) Reflection in C++11

This is yet another trick to achieve reflection-like functionality before Reflection TS, this time needing only C++11. It’s based on using CRTP to fill the object with carefully chosen garbage before initialisation.

Reflection in C++14

How to write a template function that takes a class and executes type-dependent code on all its member variables, without requiring the class to specifically support it?

Optimising a scene for VR in Unreal Engine

Since I bought Oculus Quest, I felt that it lacked a proper Doom-like action shooter. I created a scene in the editor based on what I envisioned, but it was absolutely impossible to run on Oculus Quest. This article describes various tricks I have used to bring it to Quest without too much sacrifice.

Using vectors in place of hashtables – not as dumb as it seems

Vector can find elements in linear time, hashtable in constant time. That’s a pretty elementary part of computer science. However, better complexity does not always mean it’s faster.

Development for Oculus Quest is totally doable on Ubuntu 20.04 LTS

So I was told that Oculus SDK is Windows only and Linux gets no love. Bullshit.

Super compact serialisation of C++ classes

How about defining the variable, initialising it and writing code for serialisation and deserialisation on a single line of code?

Generic self-registering factory – no more need to write factories

It’s somewhat annoying that a factory needs to depend on all classes that inherit from the common interface. This issue can be avoided using a self-registering factory.

Writing a JSON library in 2 hours in C++

C++ has a bad reputation for long times needed for development. However, as this task has shown, it does not deserve this reputation.