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DX11 How do I work with ID3D10Include::Open()?

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Hi guys, since yesterday I want to try to include additional HLSL Shader Files with the D3DX11 Effect Framework but I have none success. As I looked to the documentation, I found out that I have to create a class which inherits from ID3D10Include and I have to write the functions Open() and Close(). I think Close() isn't a problem, but Open(). As I read from documentation, I'm reading "A user-implemented method for opening and reading the contents of a shader #include file.". So I'm understanding that I have to read the content from a file and save it into ppData. Am I right?
// The defined open Method for ID3D10Include
STDMETHOD(Open)(D3D10_INCLUDE_TYPE IncludeType, LPCSTR pFileName, LPCVOID pParentData, LPCVOID *ppData, UINT *pBytes)
{
	// Read the file content
	FILE *f = fopen(pFileName, "rb");
	if(f == nullptr)
	{
		char buffere[2048];
		sprintf_s(buffere, 2048, "Could not load the effect include file \"%s\".", pFileName);
		BSX_ERROR(buffere);
		return E_FAIL;
	}

	// Get the file size
	fseek(f, 0, SEEK_END);
	long sz = ftell(f);
	fseek(f, 0, SEEK_SET);

	// Get the file content
	char *buffer = new char[sz];
	fread(buffer, 1, sz, f);
	fclose(f);

	// Save the file data into ppData and the size into pBytes.
	*ppData = buffer;
	pBytes = new UINT; *pBytes = UINT(sz);
		
	// return E_FAIL; // Because it isn't successfull supported...
	return S_OK;
}
But it doesn't work and my shader is telling me, that the definitions from the include file are not known. Another possibility I checked out was to compile the shader file. But here the shader will completly fail. The ID3D10Include::Open() should be identical with it from D3D9 and D3D10 the documentation says. Has somebody an idea where the problem is or knows my ideologic error? [oh] Thank you

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First, your code has an error. pBytes is being passed in so that you can set the size, not create a new UINT. Your code should read *pByte = sz; It's not working right now because the size value after the call to open would still be zero and your memory would be leaked.


The other thing is that the compiler will search for include files automatically in the same directory as the file you are trying to compile (provided that the include object is NULL). If I recall correctly, I believe that it even recursively searches down the sub directories. This interface is more useful for doing things like opening resources that are in the exe, like a resource file, or unpacking shaders that are in zip files.

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Oh my god, and now it works fine.

Sometimes I watching hours to the monitor and a can't find the bug. What for an horror to waste time for this simple bug.

Really really thank you! [smile] And the day is saved!

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      Setting the Pipeline State and Committing Shader Resources
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      The final step is to set states that are not part of the PSO, such as render targets, vertex and index buffers. Diligent Engine uses Direct3D11-syle API that is translated to other native API calls under the hood:
      ITextureView *pRTVs[] = {m_pRTV}; m_pContext->SetRenderTargets(_countof( pRTVs ), pRTVs, m_pDSV); // Clear render target and depth buffer const float zero[4] = {0, 0, 0, 0}; m_pContext->ClearRenderTarget(nullptr, zero); m_pContext->ClearDepthStencil(nullptr, CLEAR_DEPTH_FLAG, 1.f); // Set vertex and index buffers IBuffer *buffer[] = {m_pVertexBuffer}; Uint32 offsets[] = {0}; Uint32 strides[] = {sizeof(MyVertex)}; m_pContext->SetVertexBuffers(0, 1, buffer, strides, offsets, SET_VERTEX_BUFFERS_FLAG_RESET); m_pContext->SetIndexBuffer(m_pIndexBuffer, 0); Different native APIs use various set of function to execute draw commands depending on command details (if the command is indexed, instanced or both, what offsets in the source buffers are used etc.). For instance, there are 5 draw commands in Direct3D11 and more than 9 commands in OpenGL with something like glDrawElementsInstancedBaseVertexBaseInstance not uncommon. Diligent Engine hides all details with single IDeviceContext::Draw() method that takes takes DrawAttribs structure as an argument. The structure members define all attributes required to perform the command (primitive topology, number of vertices or indices, if draw call is indexed or not, if draw call is instanced or not, if draw call is indirect or not, etc.). For example:
      DrawAttribs attrs; attrs.IsIndexed = true; attrs.IndexType = VT_UINT16; attrs.NumIndices = 36; attrs.Topology = PRIMITIVE_TOPOLOGY_TRIANGLE_LIST; pContext->Draw(attrs); For compute commands, there is IDeviceContext::DispatchCompute() method that takes DispatchComputeAttribs structure that defines compute grid dimension.
      Source Code
      Full engine source code is available on GitHub and is free to use. The repository contains tutorials, sample applications, asteroids performance benchmark and an example Unity project that uses Diligent Engine in native plugin.
      Atmospheric scattering sample demonstrates how Diligent Engine can be used to implement various rendering tasks: loading textures from files, using complex shaders, rendering to multiple render targets, using compute shaders and unordered access views, etc.

      Asteroids performance benchmark is based on this demo developed by Intel. It renders 50,000 unique textured asteroids and allows comparing performance of Direct3D11 and Direct3D12 implementations. Every asteroid is a combination of one of 1000 unique meshes and one of 10 unique textures.

      Finally, there is an example project that shows how Diligent Engine can be integrated with Unity.

      Future Work
      The engine is under active development. It currently supports Windows desktop, Universal Windows, Linux, Android, MacOS, and iOS platforms. Direct3D11, Direct3D12, OpenGL/GLES backends are now feature complete. Vulkan backend is coming next, and Metal backend is in the plan.
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