I'm finishing a project for college in C using freeglut (2.8.1), GLEW 1.10.0, Visual Studio 2012 and Windows 8.1. It's nearly done but for some reason I can't read from console after something has been drawn.
For example, I draw something and then ask the user for a file to read, with new data to draw:
printf("File to read: ");
gets(fname); //with scanf the result is the same
printf("%s", fname); //just for testing
This prints the correct file name to the command line, and it reads the file correctly, however, for some reason, before the new data is displayed the entire thing crashes with the following error:
Unhandled exception at 0x73D3FB6D (freeglut.dll) in CV_TP1.exe: 0xC0000005: Access violation writing location 0x000000D4.
If I remove the gets/scanf and hard-code the file name the program works correctly. The same if I try to read something before all the openGL initializations, right at the top of the main function.
Related
I'm stumped... it took me a while to track this down.. because I don't have visual C++ IDE installed on the problematic system (it is windows server 2019)... my code works fine with VS 2022 on my laptop (W11 22H2)... anyhow.. I get this exception
Cannot create a file when that file already exists
I tracked it down to this code:
const auto fileTime = fs::last_write_time(p);
apparently this function can also write to the file to modify the time.
but I'm just trying to read it... (I didn't add the arguments necessary to write)
does anyone have any idea why this error might be happening?
https://en.cppreference.com/w/cpp/filesystem/last_write_time
please note it is highly likely that sometimes the file is actually being written to when I call this code (this code is called in a loop, and so is the file that is being written by another program)
I need to read an image in OpenCV, send it to DirectX, do some processing, and then send the output image back to OpenCV. I am completely new to this, and was working with DirectX 11, therefore, I decided to refer this sample which demonstrates OpenCV and DirectX interoperability. There are options for both GPU and CPU modes, but right now, I plan to use only the CPU. The program builds without any errors, but returns the following runtime error everytime:
Exception thrown at 0x0000000000000000 in Direct3D Win32 my_project_name.exe: 0xC0000005: Access violation executing location 0x0000000000000000. occurred
I looked for solutions everywhere but couldn't find any. Since this is a sample, I guess many people might have used this.
Here are the lines where I'm getting an exception.
if (cv::ocl::haveOpenCL())
{
m_oclCtx = cv::directx::ocl::initializeContextFromD3D11Device(m_pD3D11Dev); //this is the line which throws the exception
}
m_oclDevName = cv::ocl::useOpenCL() ?
cv::ocl::Context::getDefault().device(0).name() :
"No OpenCL device";
On hovering the cursor above m_pD3D11Dev, this message is displayed by the intellisense:
m_pD3D11Dev | 0x000001f5a286c618 <No type information available in symbol file for d3d11.dll>
I am guessing that there is some error in my setup or some other linker error since this is a sample code provided by OpenCV(which i am assuming is obviously going to run). Any help or guidance would be appreciated.
I'm using DirectX 11 and OpenCV 3.4.4 to build(x64) this in Visual Studio 19. I also tried building(x64) it in Visual Studio 17, but the results were same.
Thanks in advance.
I have been trying to get into DirectX programming lately (with C++/Win32), and I encountered some issues.
A friend programmed a very simple random terrain generator that works with Perlin Noise, so I tried to grab his code and make a DirectX 11 renderer for it, but my program throws an "Microsoft C++ Exception", _com_error when I run it.
Even wierder, the program breaks at different lines of code depending on the build type...
On Debug, the program breaks on this chunk of code:
// Load the pixel shader
std::ifstream pixelFile("pixel.cso");
if (!pixelFile)
return false;
std::string pixelContents((std::istreambuf_iterator<char>(pixelFile)),
std::istreambuf_iterator<char>());
pixelFile.close();
if (FAILED(mpDevice->CreatePixelShader(pixelContents.c_str(),
pixelContents.size(),
NULL,
&mpPixelShader)))
return false;
And on Release:
// Create and set the input layout
if (FAILED(mpDevice->CreateInputLayout(layoutDescription,
layoutDescriptionSize,
vertexContents.c_str(),
vertexContents.length(),
&mpVertexLayout)))
return false;
mpPixelShader is a member of type ID3D11PixelShader*, and mpVertexLayout is a member of type ID3D11InputLayout*.
Of course, the first thing I thought when I saw that the error was different was checking for memory corruption, and sure enough I found one in my friend's code after running ApplicationVerifier and setting the _crtDbgFlag, but it is fixed now and I still have this error...
The application ran fine when the rendering initialization function was filled with a modified version of the one found on the MSDN Win32 DirectX Triangle Tutorial too.
The cso file is not a text, it is a binary file. A std::string will not work, the file will contains bytes that are 0.
How can I set and get the text from a RichEditBox in an Windows 8 C++ App.
I already tried these two approaches, but the program keeps crashing at runtime
cpp
contentText->Document->Selection->GetTextViaStream(Windows::UI::Text::TextGetOptions::FormatRtf, outstream);
contentText->Document->GetText(Windows::UI::Text::TextGetOptions::FormatRtf, tempOutput);
.h
private:
Platform::String^* tempOutput;
Windows::Storage::Streams::IRandomAccessStream^ outstream;
If you program crashes, that's a good thing. It doesn't actually "crash". It throws an exception and your debugger, once attached, will catch it and tell you exactly what went wrong. Next time, start your application with F5. Once it crashes, the debugger will show you what line the problem is in and you can watch all variables to check what went wrong.
In this case, make sure that
contentText is not NULL
Document is not NULL
tempOutput is initialized to a real object
Example:
Platform::String^ tempOutput = gcnew Platform::String();
Recently I have been developing a small OpenGL game. Everything in it runs fine with the debug build but when I build the release, I get a strange Access Violation exception.
I searched across the code and it seems that the problem occurs when I try to open a file. Here is the function where I think the problem is coming from:
#define LOCAL_FILE_DIR "data\\"
#define GLOBAL_FILE_DIR "..\\data\\"
std::string FindFile(const std::string &baseName)
{
std::string fileName = LOCAL_FILE_DIR + baseName;
std::ifstream testFile(fileName.c_str()); // The code breaks here
if(testFile.is_open())
return fileName;
fileName = GLOBAL_FILE_DIR + baseName;
testFile.open(fileName.c_str());
if(testFile.is_open())
return fileName;
throw std::runtime_error("Could not find the file " + baseName);
}
This code is associated with loading of GLSL shaders. A function takes the shader's file name and then passes it to FindFile in order to find the file needed.
Just as a general rule from personal (and teaching) experience: >90% of the cases where Debug works fine and Release crashes are due to uninitialized variables. That's a little harder to do in C++ than in C, but it is a very common problem. Make sure all your vars (like baseName) are initialized before using them.
I fixed the problem.
Everything was happening because I have made the Release build using glsdk's Debug build libraries. Changing to the Release build libraries fixed the problem.
Check that baseName is valid. Try printing it out. You may be getting a corrupted copy of baseName or your stack may have gotten trashed prior to that point (same result).