Why does D3DX11CreateShaderResourceViewFromMemory only upload a partial copy of my texture? - directx-11

Question

I have a problem with the D3DX11CreateShaderResourceViewFromMemory helper function.
I read some texture from a file or ZIP and pass the raw bytes and length to the helper function, however only part of the texture is uploaded (as confirmed by PIX).
I tried fiddling with the length manually but to no avail.
Here is the code that loads the texture from file:
struct FileDataLoader
{
void Load()
{
std::ifstream file(mFileName);
if (file)
{
file.seekg(0,std::ios::end);
std::streampos length = file.tellg();
file.seekg(0,std::ios::beg);
mBuffer.resize(length);
file.read(&mBuffer[0],length);
file.close();
}
}
void Decompress(void*& data, std::size_t& numBytes)
{
data = &mBuffer[0];
numBytes = mBuffer.size();
}
std::wstring mFileName;
std::vector<char> mBuffer;
};
FileDataLoader fdl;
fdl.mFileName = L"Content\\Textures\\Smoke.dds";
fdl.Load();
void* bytes;
std::size_t size;
fdl.Decompress(bytes, size);
DXCall(D3DX11CreateShaderResourceViewFromMemory(device, bytes, size, NULL, NULL, &particleTexture, NULL));
That is only a sample code that I am using to debug this problem, and I narrowed it down to the file loading and the D3DX helper function.
Now if I do this instead:
DXCall(D3DX11CreateShaderResourceViewFromFileW(device, L"Content\\Textures\\Smoke.dds", NULL, NULL, &particleTexture, NULL));
it works perfectly fine.
Any idea on why it would not upload the texture entirely ?

Answer 1

When opening the file, you need to specify that the file is binary:
std::ifstream file( fileName, std::ios::in | std::ios::binary );
Without the std::ios::binary flag you're reading in plain text by default, which is not what D3DX11CreateShaderResourceViewFromMemory expects.