Questions about C++, a statically typed, free-form, multi-paradigm, compiled, general-purpose programming language.

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2
votes
1answer
99 views

class hierarchy with structurally different subclasses

I want to implement a protocol layer which sits on top of the TCP/IP stack. There is a limited set of PDUs that can be sent and for each PDU there is a class which represents it in a structured form. ...
1
vote
1answer
194 views

How should a GUI application written in WinAPI be structured and organized? [closed]

I've done an extensive amount of GUI programming in Winforms and WPF using C#, and a tiny bit in C++ using MFC. I'm building a personal project using WinAPI mainly to gain a deeper knowledge in ...
2
votes
1answer
247 views

Best practice for unused inherited virtual functions (implementing superclass methods)

Let's assume I have a hierarchy of several classes each derived from each other using virtual functions. The base class acts as an interface and defines functions, which may not be required by all of ...
-2
votes
1answer
117 views

Uniqueness of for loop [closed]

How does the for loop function is implemented so that it can accept ; as parameter separator rather than , which is trivial in normal functions.
0
votes
2answers
128 views

C++ Data Server and J2ME client communication [closed]

I am working on a robot that has some AI built in. However, the mandated robot controller does not have the power to do the work onboard. This means that I need to use a co-processor. I am writing ...
1
vote
7answers
708 views

Where is the 'this' variable stored?

Let's take this simple c++ program as an example: #include <vector> class A { void fun() { a = this + 1; } A* a; }; main() { std::vector<A> vec; vec.resize(100); } Forgetting ...
1
vote
2answers
1k views

2D linked list vs. multidimensional array/vector

I hope that programmers is the correct stack exchange for this, as it is quite a concept based question. I'm working on a data structure in C++ that is a represents data in 3D space. The x-y plane is ...
4
votes
1answer
451 views

Why did GCC switch from Bison to a recursive descent parser for C++ and C?

Was there a language change that required it or some practical reason why Bison was no longer appropriate or optimal? I saw on wikipedia that they switched, referring to the GCC 3.4 and GCC 4.1 ...
1
vote
1answer
141 views

Multithreaded Pre/Post Functions

I'm programming an application for an embedded device. We are using an RTOS that supports multi threading. The device is supposed to mimic an older project that was programmed in plain C (without ...
2
votes
1answer
108 views

Drawing a custom rendered control in Windows - resizing

Some background: in order to learn GUI programming and drawing in Windows I'm starting to create my own GUI toolkit in Windows (so this is a didactic exercise, please don't suggest "use Qt" or "use ...
3
votes
1answer
247 views

Is my class structure good enough?

So I wanted to try out this challenge on reddit which is mostly about how you structure your data the best you can. I decided to challenge my C++ skills. Here's how I planned this. First, there's ...
0
votes
1answer
265 views

Cheerp — C++ for web: advance or regression? [closed]

Recently I've run into Cheerp, a C++ to Javascript compiler, which uses a modified version of clang to generate Javascript code from C++ sources. That makes me wonder: why in the seven kingdoms would ...
3
votes
7answers
2k views

Why do we need to include the .h while everything works when including only the .cpp file?

Why do we need to include both the .h and .cpp files , while we can make it works with making just a .cpp file and then including it . For example, Creating a file.h containing declarations, then ...
23
votes
8answers
2k views

Interface design where functions need to be called in a specific sequence

The task is to configure a piece of hardware within the device, according to some input specification. This should be achieved as follows: 1) Collect the configuration information. This can happen at ...
-2
votes
1answer
238 views

What are steps in making an operating system in C ? [duplicate]

I am trying to make an my own OS. This is for educational purpose only, so that I get to understand the internals as well as get a good idea of low level programming. I have some prior application ...
3
votes
1answer
145 views

Augmenting functionality of subclasses without code duplication in C++

I have to add common functionality to some classes that share the same superclass, preferably without bloating the superclass. The simplified inheritance chain looks like this: Element -> ...
5
votes
2answers
410 views

C++ Without Source Files

Bjarne Stroustrup mentions in his book "The C++ Programming Language, 4th Edition" that not all C++ implementations use files to store and compile code: There are systems that do not store, ...
8
votes
2answers
332 views

Is NAN suitable for communicating that an invalid parameter was involved in a calculation?

I am currently working on a numerical processing system that will be deployed in a performance-critical environment. It takes inputs in the form of numerical arrays (these use the eigen library, but ...
2
votes
4answers
227 views

How to refactor a myriad of similar classes

I'm faced with similar classes A1, A2, ..., A100. Believe it or not but yeah, there are roughly hundred classes that almost look the same. None of these classes are unit tested (of course ;-) ). Each ...
1
vote
1answer
238 views

Implementation of instance testing in Java, C++, C#

For curiosity purposes as well as understanding what they entail in a program, I'm curious as to how instance testing (instanceof/is/using dynamic_cast in c++) works. I've tried to google it ...
-2
votes
2answers
126 views

Does a custom scripting language require it's own compiler/assembler? [closed]

Or is the script generally converted to a known language such as C++ first? And how generally to you integrate a scripting language with the say a game engine?
1
vote
2answers
189 views

Is it an anti-pattern to use void* and enums to enable type-checking?

Say in a game engine, you have Objects that composited of different components. One of these is a RenderComponent which can be either a Mesh, a Sprite or a Light. Now, all these are vastly different ...
1
vote
1answer
202 views

In C++, are acquire-release memory order semantics transitive?

According to cppreference, we can use release-acquire semantics to ensure write-read precedence between two threads as follows: // Thread A 1. Write to X 2. Atomic store to Y with ...
-2
votes
2answers
60 views

Know executables files launched/loaded by an executable file [closed]

I would like to know any executable files launched or loaded by an executable file (if possible without running it,if it is not possible i don't want any change in the system). For example i have ...
0
votes
5answers
293 views

Should we only catch in exceptional circumstances?

Whether error handling by throwing exceptions is good or bad is contentious. Are exceptions as control flow considered a serious antipattern? If so, Why? The common line is that exceptions are for ...
-4
votes
1answer
240 views

Calculate Pi to N number of places [closed]

I am trying to work out how to calculate Pi to N decimal places, I think the default DP's for a float/double is 5 and then you have setprecision() however these are obviously inadequate, I need ...
-4
votes
1answer
128 views

Unable to understand linked list example [closed]

Could someone please explain this code to me.. #include <iostream> using namespace std; struct link { int data; link* next; }; class linklist { private: link* first; ...
-5
votes
2answers
2k views

How does std::string in c++ allocate memory? [closed]

I've noticed that the string library doesn't require one to allocate space before writing the input/output. How does the string library allocate that memory dynamically, i know of the 'new' keyword in ...
-2
votes
3answers
153 views

Distributed game development and security of source code

I think this question has already been asked many times, but I can't find any of them. I have a game project (I'm using Marmalade),and a few trusted developers, but I want to invite more. For adding ...
3
votes
3answers
400 views

C/C++: Which conversion warnings make sense in practice?

C/C++ implicit conversions can cause bugs. Here's one example: int foo, bar; scanf("%d", &foo); scanf("%d", &bar); float foobar = foo / bar; If I input 7 and 2, it's not 3.5 as expected - ...
1
vote
1answer
158 views

Pulling results from postgresql with cursors

I'm writing an application in C++ using libpq as the interface to postgresql. I'm currently putting together a small library of helper functions to help deal with the conversion from C++ to C for an ...
12
votes
3answers
764 views

Debugging memory corruption

First off, I do realize this is not a perfect q&a style question with an absolute answer, but I can't think of any wording to make it work better. I don't think there is an absolute solution to ...
0
votes
1answer
153 views

Is this a specific pattern and what is its purpose? [closed]

I recently stumbled over the following C++ Code which confused me a bit: class One {/*definition*/}; template<class Base > class Two : public Base {/*definition*/}; template<class Base > ...
-1
votes
2answers
213 views

Reading assembly useful for insights when writing C/C++? [closed]

While in most cases its not necessarily, recently I have taken to reading the generated assembly of my C code every so often, when I'm curious as to the kinds of optimizations my compiler is making. ...
5
votes
2answers
255 views

Processor architectures for testing C/C++ portability

Currently I'm working on a C/C++ code-base which is fairly portable, it can compile on most Unix like systems as well as MS-Windows (MSVC), using various popular compilers. Previously I've found ...
2
votes
1answer
108 views

How modularized should my interfaces be?

I stumbled upon a specific instance where it seems that modularity and simplicity are at conflict with each other. Usually that's not the case, so I was really unsure how to resolve it. Suppose I ...
20
votes
3answers
4k views

Why Increment Pointers?

I just recently started learning C++, and as most people (according to what I have been reading) I'm struggling with pointers. Not in the traditional sense, I understand what they are, and why they ...
4
votes
1answer
93 views

How to define the motion path of one object on a surface of the other one?

I have an uncommon problem. There are 2 3D objects, which are represented by arrays of vertices and triangles (.stl files). Each of them contains a big enough amount of vertices: 1-10 mln ones. The ...
4
votes
1answer
245 views

Is there a reason to define type aliases in any program

I have started to learn c++ for some time ago. It is a big subject and I am not very use to it yet. Thus is this question asked more of curiosity, than something else. In the book that I read to now ...
9
votes
5answers
986 views

Are there technical limitations or language features that prevent my Python script from being as fast as an equivalent C++ program?

I'm a long-time Python user. A few years ago, I started learning C++ to see what it could offer in terms of speed. During this time, I would continue to use Python as a tool for prototyping. This, it ...
0
votes
5answers
456 views

IS C++ a cross-platform language? [closed]

If I create a game in C++ on a mac using a library which is the same for both windows and osx, will the game be playable on both windows and os x or it will only work in os x because I done it in ...
2
votes
1answer
136 views

Is there a way to use RAII techniques in COM?

I am caught between two conceptual models of how to construct objects, and am having trouble working out what standard I want to adopt. I prefer to program in .NET and often try to use RAII and ...
-2
votes
2answers
306 views

Which algorithm is faster? [closed]

I'm creating a small game, where the computer generate pseudo random number in give range, and the user have to guess it. I also made the option to play computer vs computer. I mean the computer ...
0
votes
1answer
77 views

Is it a bad idea to use mutable for pre-allocated temporaries?

Let us assume I have the following C++ class: class MyFastMessageEncoder { public: MyFastMessageEncoder() : m_fieldEncoder(ENCODING_STYLE_DEFAULT) { } void ...
-2
votes
2answers
304 views

How comes the C++ standards committee introduces a keyword like nullptr and gets away with it? [closed]

That must have broken a lot of peoples code bases right? Everyone who had a variable named "nullptr" (which I think would have been fairly common) has to find "nullptr" and replace with ...
2
votes
2answers
149 views

Potentially justifiable use case for const_cast or bad design?

I'm designing a data structure in C++, and I want to expose an interface to the user to traverse the structure in some order. Instead of creating several different types of enumerators, I want to keep ...
1
vote
0answers
139 views

Dynamic programming in Bin packing

Problem: Given a list L of objects of possible sizes from set S={1,2,4,8} and unlimited supply of bins of sizes 16 each and we have to use minimum possible numbers of bins to pack all objects of L. I ...
2
votes
1answer
131 views

OpenGL's relationship to OpenGL ES (3.0)

I'm beginning my journey into graphics programming and want to learn OpenGL. Because I'm green to graphics programming but not to C and C++, a familiar question came up when I looked at OpenGL and ...
0
votes
3answers
996 views

Is there still any value in learning assembly languages today? [closed]

Specifically for a game programmer. If you really needed some assembly routines you could look for help, whereas back in the 80s/90s it was one of the mainstream languages. I read that compilers can ...
2
votes
1answer
557 views

Why is C++ “this” poorly designed?

1) For every a and b which are non-const pointers of the same type, you can do a = b;, right? 2) Inside non-const member functions the this keyword exists, which is a non-const pointer. So logicaly ...