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# DX11 DirectX11 mesh loading - error because of textures (using SDKmesh.h)? Access violation reading location 0x00000000

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I was trying to load a mesh from file in my DirectX 11 application.
As the base I took my own code (that renders some Primitives now) and I wanted to add to it code of mesh creating/rendering from "Basic HLSL" Project from DirectX 11 SDK Samples (which uses e.g. SDKmesh.h and DXUT.h from samples.

The mesh code is:
I was trying to load a mesh from file in my DirectX 11 application.
As the base I took my own code (that renders some Primitives now) and I wanted to add to it code of mesh creating/rendering from "Basic HLSL" Project from DirectX 11 SDK Samples (which uses e.g. SDKmesh.h and DXUT.h from samples.

The mesh code is:

[source lang="cpp"]
class FeyModel : public Graphic::Model, public FeyGraphicElement{
protected:
CDXUTSDKMesh mesh;
public:
FeyModel(ID3D11Device * device, std::string filename, const Common::Point3D center){
mesh.Create( device, L"tiny\\tiny.sdkmesh", false ); //for now tiny.sdkmesh
}

void render(FeyShader * shader,
FeyCamera * camera,
ID3D11DeviceContext* context,
float t
){

UINT Strides[1];
UINT Offsets[1];
ID3D11Buffer* pVB[1];
pVB[0] = mesh.GetVB11( 0, 0 );
Strides[0] = ( UINT )mesh.GetVertexStride( 0, 0 );
Offsets[0] = 0;
context->IASetVertexBuffers( 0, 1, pVB, Strides, Offsets );
context->IASetIndexBuffer( mesh.GetIB11( 0 ), mesh.GetIBFormat11( 0 ), 0 );

SDKMESH_SUBSET* pSubset = NULL;
D3D11_PRIMITIVE_TOPOLOGY PrimType;

//! context->PSSetSamplers( 0, 1, &samLinear );

for( UINT subset = 0; subset < mesh.GetNumSubsets( 0 ); ++subset )
{
// Get the subset
pSubset = mesh.GetSubset( 0, subset );

PrimType = CDXUTSDKMesh::GetPrimitiveType11( ( SDKMESH_PRIMITIVE_TYPE )pSubset->PrimitiveType );
context->IASetPrimitiveTopology( PrimType );

// TODO: D3D11 - material loading

ID3D11ShaderResourceView* pDiffuseRV = mesh.GetMaterial( pSubset->MaterialID )->pDiffuseRV11;

context->PSSetShaderResources( 0, 1, &pDiffuseRV );

context->DrawIndexed( ( UINT )pSubset->IndexCount, 0, ( UINT )pSubset->VertexStart );
}
}
};[/source]

I have also noticed that in the sample, there was a different vertex layout, so I have changed my shader's class code to (the code will be executed once, in shader's class constructor, before mesh creating):

[source lang="cpp"]
...
const D3D11_INPUT_ELEMENT_DESC layout[] =
{
{ "POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D11_INPUT_PER_VERTEX_DATA, 0 },
{ "NORMAL", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 12, D3D11_INPUT_PER_VERTEX_DATA, 0 },
{ "TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT, 0, 24, D3D11_INPUT_PER_VERTEX_DATA, 0 },
};

UINT numElements = ARRAYSIZE( layout );

// Create the input layout
hr = device->CreateInputLayout( layout, numElements, pVSBlob->GetBufferPointer(), pVSBlob->GetBufferSize(), &*vertexLayout );
pVSBlob->Release();

// Set the input layout
context->IASetInputLayout( *vertexLayout );
...
[/source]

The compilation works. But during the execution of code I get error:

Access violation reading location 0x00000000

In SDKmish.h near:

[source lang="cpp"]if (bSRGB) {
// This is a workaround so that we can load linearly, but sample in SRGB. Right now, we can't load
// as linear since D3DX will try to do conversion on load. Loading as TYPELESS doesn't work either, and
// loading as typed _UNORM doesn't allow us to create an SRGB view.

// on d3d11 featuer levels this is just a copy, but on 10L9 we must use a cpu side copy with 2 staging resources.
ID3D11Texture2D* unormStaging = NULL;
ID3D11Texture2D* srgbStaging = NULL;

D3D11_TEXTURE2D_DESC CopyDesc;
pRes->GetDesc( &CopyDesc );

pLoadInfo->BindFlags = 0;
pLoadInfo->CpuAccessFlags = D3D11_CPU_ACCESS_WRITE | D3D11_CPU_ACCESS_READ;
pLoadInfo->Depth = 0;
pLoadInfo->Filter = D3DX11_FILTER_LINEAR;
pLoadInfo->FirstMipLevel = 0;
pLoadInfo->Format = CopyDesc.Format;
pLoadInfo->Height = CopyDesc.Height;
pLoadInfo->MipFilter = D3DX11_FILTER_LINEAR;
pLoadInfo->MiscFlags = CopyDesc.MiscFlags;
pLoadInfo->Usage = D3D11_USAGE_STAGING;
pLoadInfo->Width = CopyDesc.Width;

CopyDesc.BindFlags = 0;
CopyDesc.Usage = D3D11_USAGE_STAGING;
CopyDesc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE | D3D11_CPU_ACCESS_READ;
CopyDesc.Format = MAKE_SRGB(CopyDesc.Format);

hr = D3DX11CreateTextureFromFile( pDevice, pSrcFile, pLoadInfo, pPump, ( ID3D11Resource** )&unormStaging, NULL );
DXUT_SetDebugName( unormStaging, "CDXUTResourceCache" );

hr = pDevice->CreateTexture2D(&CopyDesc, NULL, &srgbStaging);
DXUT_SetDebugName( srgbStaging, "CDXUTResourceCache" );
pContext->CopyResource( srgbStaging, unormStaging );
ID3D11Texture2D* srgbGPU;

pRes->GetDesc( &CopyDesc );
CopyDesc.Format = MAKE_SRGB(CopyDesc.Format);
hr = pDevice->CreateTexture2D(&CopyDesc, NULL, &srgbGPU);
pContext->CopyResource( srgbGPU, srgbStaging );

SAFE_RELEASE(pRes);
SAFE_RELEASE(srgbStaging);
SAFE_RELEASE(unormStaging);
pRes = srgbGPU;
}[/source]

Precisely in the line:
[source lang="cpp"]
pContext->CopyResource( srgbStaging, unormStaging );[/source]

When I comment few lines of that function and something in my code (I now can't remember what line were that) I get the mesh in the window, but without textures. So I guess it's something with textures? I have the tiny model and texture in the proper folder, I have also set vertex layout like I have posted above.

What else should I do?

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Please consider checking HREULT values for method Create and others.
Maybe you would pass a cannonical path instead of its short form.

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• By cozzie
Hi all,
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• By chiffre
Introduction:
In general my questions pertain to the differences between floating- and fixed-point data. Additionally I would like to understand when it can be advantageous to prefer fixed-point representation over floating-point representation in the context of vertex data and how the hardware deals with the different data-types. I believe I should be able to reduce the amount of data (bytes) necessary per vertex by choosing the most opportune representations for my vertex attributes. Thanks ahead of time if you, the reader, are considering the effort of reading this and helping me.
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(TLDR at bottom)
The Actual Post:
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• By cozzie
Hi all,
I was wondering it it matters in which order you draw 2D and 3D items, looking at the BeginDraw/EndDraw calls on a D2D rendertarget.
The order in which you do the actual draw calls is clear, 3D first then 2D, means the 2D (DrawText in this case) is in front of the 3D scene.
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A - Begin frame, clear D3D RT
B - Draw 3D
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E - EndDraw D2D RT
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B - Draw 3D
C - Draw 2D
D - EndDraw D2D RT
E- Present
Would there be a difference (performance/issue?) in using option 2? (versus 1)
Any input is appreciated.

• Do you know any papers that cover custom data structures like lists or binary trees implemented in hlsl without CUDA that work perfectly fine no matter how many threads try to use them at any given time?
• By cozzie
Hi all,
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I can also post some more information on what happens, code and which code commented out, eliminates the problems (when running in RenderDoc).
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