Should a C++ game dev know this?…

Summary

In this engaging interview, the candidate, a junior game developer with over a year of experience in C++, discusses their journey into game development, their experiences with various C++ concepts, and their approach to problem-solving. Topics include the Rule of Five, memory management, data types, inheritance, and C++ features like virtual methods, templates, and operator overloads. Despite some gaps in technical knowledge, the candidate demonstrates strong problem-solving skills, the ability to learn quickly, and a solid understanding of game development principles, making them a strong contender for a junior dev position.

Takeaways

• 😀 The candidate has been working with C++ professionally for over a year in game development.
• 😀 They started programming in high school and were motivated by a passion for making video games.
• 😀 The candidate was asked about the 'Rule of Five' in C++, but they were unfamiliar with it initially, though they tried to reason through it.
• 😀 The 'Rule of Five' involves five special member functions: destructor, copy constructor, copy assignment operator, move constructor, and move assignment operator.
• 😀 The 'Rule of Zero' suggests that if no special resource management is needed, avoid defining custom constructors or assignment operators.
• 😀 Special member functions, such as constructors or destructors, can affect whether the compiler generates default implementations for other functions.
• 😀 The candidate was tested on their knowledge of default constructor behavior, especially when objects are declared as `const`.
• 😀 The candidate correctly answered that the size of a character in C++ is typically 1 byte, but the signed/unsigned nature is implementation-defined.
• 😀 The candidate demonstrated awareness of the fact that the size of data types like `long` is platform-dependent, particularly on 64-bit systems.
• 😀 The candidate struggled but eventually acknowledged that a class with multiple inheritance requires memory space to distinguish between its parent classes.
• 😀 The candidate showed familiarity with `std::forward`, understanding that it works with references and casting values to rvalue references, but their explanation was a bit unclear.
• 😀 The candidate was able to understand and answer questions about templates in game development, acknowledging that a virtual method can exist in a templated class, but virtual templated functions are not allowed.

Q & A

What motivated you to pursue a career in game development?

The interviewee became interested in programming during high school, starting in grade 10. Their primary motivation was their passion for video games, and they were drawn to the idea of making their own games.

How did you transition from school to your current job in game development?

After graduating, the interviewee secured a position at a game development company near their university, where they began working professionally in the field.

What is the 'Rule of Five' in C++?

The Rule of Five refers to five special member functions in C++: the destructor, copy constructor, copy assignment operator, move constructor, and move assignment operator. It states that if you define one of these, you should define the others as well to manage resources properly.

What is the 'Rule of Zero' in C++?

The Rule of Zero extends the Rule of Five by suggesting that if you don't need to manage any special resources in a class, you should avoid defining any of these special member functions. Instead, you can rely on the compiler's default behavior.

If you define a move constructor in a class, will the compiler still implicitly define other special member functions?

No, if you define a move constructor, the compiler will not implicitly generate other special member functions like copy constructors or assignment operators. However, the default constructor can still be implicitly generated.

What happens if you declare an object as const but use a default constructor that does not initialize all members?

Declaring an object as const and using a default constructor that doesn't initialize all members will result in a compilation error, as const objects must be fully initialized at the time of creation.

What is the size of a character in C++?

A character in C++ is always 1 byte, though the signedness of a char (whether it is signed or unsigned) is implementation-defined.

What is the size of a long on a 64-bit system?

The size of a long is implementation-defined, but typically it is 4 bytes on some systems (e.g., Windows) and 8 bytes on others (e.g., Linux). The C++ standard only specifies that a long should be at least as large as an int.

What is the result when a class has a diamond inheritance structure?

In a diamond inheritance structure, like when class B inherits from both A and empty, the size of the derived class can be larger than expected because the compiler must ensure that each base class's object is distinct, resulting in extra memory being allocated to differentiate them.

Why can't you have a virtual templated function in C++?

You can't have a virtual templated function because the compiler needs to know the exact type at compile time to create a virtual table. Templated functions are not resolved until the program is fully compiled, making it difficult to establish a virtual table with varying template types.