C++ - Страница 1255

I'm trying to make a png file reader in c++. I understood about the chunk structure but I'm struggling in understanding how to read the data in IDAT chunk to get each pixel color. This is my data

width: 16 height: 16 bit depth: 8 color type: 2...

I am serializing a set of contents, indexed by multiple properties using boost::multi_index_container, and a params struct, into a binary archive which I want to deserialize latter. But the archive created using boost 1.74 is unreadable (Invalid or...

I was trying to understand when the memory owned by shared (smart) pointers are cleared on calling execv() from the code.

Assume the following code:

#include class Test { public: ~Test() { std::cout

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I'm writing C++14 code which needs to deserialize objects as fast as possible.

The serialization is in memory and occurs in the same process as the deserialization.

Consider this:

struct Base { Base(const int a) : a {a} { } int a; }; struct...

I need to call the C class object like this -

int main() { C c1; C c2; } I have this code so far -

template class A { ..... }; template class B { ..... }; template struct Pair // wrap a generic type { pair p; } template class C { tuple v; //...

So i need to install Qt Creator 3.2.0 and build a project. But, when i try to open the project right now, it is saying Could not find qmake configuration file default .

Here is my version info:

Qt Creator 3.2.0

Based on Qt 5.3.1

Built on...

As far as I know, a property of the standard-layout class is that the address of a standard-layout object is equal to its initial member's. I tested the following code with g++ and clang++, but found that Derived3 is a standard-layout class and &d...

I am just starting with C++ and am creating a simple text-based adventure. I am trying to figure out how to have probability based events. For example a 50% chance that when you open box there will be a sword and a 50% chance it will be a knife. I...

I am working on a video processing project which needs some flipping of frame. I tried using cvFlip but doesnt seem to flip along y axis (x axis working...) and results in segmentation fault. Is there any other option??
cv::Mat dst=src; //src=...

enter image description here

What is the benefit of code from line 44 to 60? Or if I delete these lines the all code will be wrong or give another output?

I expect the code will work well because this lines was copied from if condition I want to...

I'm currently working on a project related to Formula 1, where I display updates from a webpage, for my virtual F1 league and FIA decisions on a webpage. I also integrate this content into Twitch streams using OBS's web feature and send custom...

I have a struct with a union inside. How can I make a get_data() function that should return a bool if(value == input_value::_bool).

enum class input_value { _bool, _1D, _2D, _3D, }; struct input_action { union input_action_data { bool boolean;...

I have a very similar problem to one described on the cmake mailing list where we have a project dependent on many static libraries (all built from source in individual submodules, each with their own CMakeLists.txt describing the build process for...

I'm using IWICImagingFactory::CreateDecoderFromFilename() for reading only. Is there a way I can pass something like the FILE_SHARE_READ flag? The file stays open from the function call above until the program terminates.

During another operation...

I am building an endpoint that requires 2 query parameters: email_address and token, the issue I am seeing is that when I make the following call from Postman every other click is an error:

The error message:

server=oatpp/1.3.0 code=404...

I am currently getting a list of compilation errors when attempting to run my program - I figure they specifically stem from a specific red-line funking things up however. The specific line is

context->states->Add(std::make_unique(context));

in...

I am trying to set up a data-based qml element list. As a first step I just want to update the list by data, not by manual input. In the constructor of the list I append 2 list elements. After that, I want to update the list by data from an external...

Is there anything like boost::thread_group in C++11?

I'm just trying to port my program from using boost:thread to C++11 threads and wasn't able to find anything equivalent.

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I want to add a simple python interface on a large c++ project so that I can call some c++ functions using python. It is a large c++ project and the structure is like

FastBN -src // many source files inside -include // many header files inside...

I have two buffers, both of the same size and type (uint32_t*). These buffers are supposed to represent the front and back buffers of a rendering/drawing system. They store 32-bit pixel data.

I declare and initialize these buffers using;...

I'm working on a college project in C++ that involves implementing a Folder Cleaner using Data Structures and Algorithms (DSA). The requirements for the project are as follows:

Project Description:
Folder Cleaner: The task is to build a Folder...

I can't use the Clion 2023.3 to compile cpp20 modules code successfully. Here is the code:

//Hello.cppm #include export module Hello; export void hello() { std::cout

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I’m currently working on a project that involves creating property handlers for .txt files. My goal is to add a new page to the properties of a .txt file using a property handler. However, I’m facing some issues and the handler isn’t functioning as...

I'm writing my own control. It contains the caret. I use the SetCaretPos() function to move the caret. And it works well when I move the caret inside the window:

But when I set a negative y-coordinate for SetCaretPos(), the caret is drawn...

I want to make use of .net dlls in node.js. Does that mean I need to make those dlls available with c/c++ using 'clr hosting', a la
.NET Framework 4 Hosting Interfaces or Hosting the Common Language Runtime
Unfortunately the example Creating a...