DX11 - Screen Tearing

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4 comments, last by REF_Cracker 11 years, 3 months ago

Has anyone ever had issues with screen tearing under DX11?

- I'm pretty sure I'm buffering properly as per the example programs.
- I present with Present(1,0);
- It is properly limiting my frame rate to 60FPS.


Here is the code I'm using to initialize the swap chain.....


    memset(&l_desc,0,sizeof(DXGI_SWAP_CHAIN_DESC));

    l_desc.BufferCount = 1;
    l_desc.BufferDesc.Width = in_width;
    l_desc.BufferDesc.Height = in_height;
    l_desc.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
    l_desc.BufferDesc.RefreshRate.Numerator = 60;
    l_desc.BufferDesc.RefreshRate.Denominator = 1;
    l_desc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
    l_desc.OutputWindow = *(HWND *)in_handle;
    l_desc.SampleDesc.Count = 1;
    l_desc.SampleDesc.Quality = 0;
    l_desc.Windowed = TRUE;

    l_result = l_d3d->QueryInterface(__uuidof(IDXGIDevice),(void **)&l_device);

    if(SUCCEEDED(l_result))
    {
        l_result = l_device->GetParent(__uuidof(IDXGIAdapter),(void **)&l_adapter);

        if(SUCCEEDED(l_result))
        {
            l_result = l_adapter->GetParent(__uuidof(IDXGIFactory),(void **)&l_factory);

            if(SUCCEEDED(l_result))
            {
                l_result = l_factory->CreateSwapChain(l_d3d,&l_desc,&m_chain);
                l_factory->Release();

                if(FAILED(l_result))
                {
                    MessageBox(NULL,"Couldn't create a swap chain on the device!","Error!",MB_OK | MB_ICONINFORMATION);
                    return false;
                }
            }

            l_adapter->Release();
        }

        l_device->Release();
    }


    l_result = m_chain->GetBuffer(0,__uuidof(ID3D11Texture2D),(LPVOID *)&l_texture2D);


Any ideas as to why I'm still getting horrible tearing? Thanks in advance!

Check out my project @ www.exitearth.com

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I am not, do not aspire to, nor ever will be, a DirectX programmer.

But, as a C programmer, I can tell you that your error checking can fail silently. I don't know exactly what that code is supposed to do, but it's possible a number of the lines never run due to an error, with no error being reported.

As a graphics programmer, I'll tell you that screen tearing is often caused by a lack of synchronization between the update rate and the refresh rate. It sounded like you already knew that.

[size="1"]And a Unix user said rm -rf *.* and all was null and void...|There's no place like 127.0.0.1|The Application "Programmer" has unexpectedly quit. An error of type A.M. has occurred.
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Thanks for the feedback! Sadly the sloppy program flow in the pasted source has nothing to do with my issue. Does anyone have a similar experience with screen tearing in DX11 and if so how did you solve it?

Check out my project @ www.exitearth.com

I'm quite certain that your problem is actually in these two lines:


    l_desc.BufferDesc.RefreshRate.Numerator = 60;
    l_desc.BufferDesc.RefreshRate.Denominator = 1;

Your monitor may not actually be refreshing at 60Hz, but instead at slightly under or slightly over the 60. Rather than just putting in hard-coded values you should enumerate your modes properly using IDXGIFactory::EnumAdapters, IDXGIAdapter::EnumOutputs and IDXGIOutput::GetDisplayModeList, then use the refresh rates provided by that enumeration instead.

Direct3D has need of instancing, but we do not. We have plenty of glVertexAttrib calls.

When in windowed mode, try using ID3D11DeviceContext::Flush before Present.

Erik Rufelt - After a lot of investigation ID3D11DeviceContext::Flush has indeed solved my problem. Funny enough this was one of my first thoughts when I started looking into the issue but then I got obsessed with the refresh rate numerator \ denominator and the fact that my monitors are stuck in 59hz (which seems to be a common issue on windows7). Anyway thank you very much as the second I added the flush it all tearing ceased!!!

mhagain - You are indeed correct that enumerating the adapters does provide me with more suitable values for the refresh rate. A quick investigation indicates that for my current desktop the proper settings would be 59950 / 1000. Sadly these settings seem to have no effect on the issue even with the solution (flush) added. None the less it is probably a good idea to use this proper setup method so thank you for pointing that out.

SOLVED!

Check out my project @ www.exitearth.com

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