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Paul C Skertich

IASetIndexBuffer Children Could Not Be Evaluated...Why?

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The editor can load one mesh. Each mesh has it's own model matrix and world matrix. Model Matrix handles the rotation, translation and scaling.

When I import a new mesh it would break in the draw function and tell me AccessVoilationException where it sets up the IndexBuffers to be drawn. My guess is that it's trying to access a region in memory that isn't there.

Each time in the Import Mesh it generates new totalVertices and totalIndexes for the model struct. Once it obtains the vertex count inside the mesh - it will createa a new size for the struct. I don't know if this could be it.

The Mesh class is outside of the managed area which is intialized with every new managed Model call.

Additionally notes, could it be because the draw function is inside the editor's timer1 form control?

C++ Managed Assembly - model struct.
[code]

struct MODEL {

ID3D11Buffer *pVBuffer; // the pointer to the vertex buffer
ID3D11Buffer *pIBuffer; // the pointer to the index buffer
ID3D11ShaderResourceView *pTexture; // the pointer to the texture

int totalVertices;
int totalIndices;

D3DXMATRIX rotation_Matrix;
D3DXMATRIX translation_Matrix;
D3DXMATRIX scale_Matrix;
D3DXMATRIX worldMatrix;
D3DXMATRIX modelMatrix;

};

MODEL *model;

[/code]

If it's able to load one mesh - this should be the problem, right?

C++ Managed Code - Model Draw Function.
[code]
void Draw() {

// select which vertex buffer to display
UINT stride = sizeof(Mesh::VERTEX);
UINT offset = 0;
devcon->IASetVertexBuffers(0, 1, &MESH->model[idCount].pVBuffer, &stride, &offset);
devcon->IASetIndexBuffer(MESH->model[idCount].pIBuffer, DXGI_FORMAT_R32_UINT, 0);

// select which primtive type we are using
devcon->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);

devcon->UpdateSubresource(pCBuffer, 0, 0, &cBuffer, 0, 0);
devcon->PSSetShaderResources(0, 1, &MESH->model[idCount].pTexture);

devcon->DrawIndexed(MESH->model[idCount].totalVertices, 0, 0);
}
[/code]

I thought because when I initialize the buffers after loading everything from file. It would understand:

[code]
MESH->model[idCount].pVBuffer
[/code]

idCount is incremented every new mesh is imported.

Would it be better to have the DrawIndexed function where I have it present the scene or in the model's draw function? Would I have to bring the cBuffer into the struct as well?

Thanks everyone!

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Ripiz    539
If [i]idCount[/i] is incremented everytime new mesh is imported are you sure you're not reading outside array? I think you need a loop here, from 0 to idCount - 1.

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I think you're right because that would make sense! MSDN said it would be unsafe handling from unmanaged code to managed code. Perhaps using a vector would be better suit this case? I read about vectors. Does it matter to have a vector or a array? Is the array above fixed and a vector container is more flexible?

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Tordin    625
Try enabeling the Dxdebuglayer, it will tell you more of what caused the error!

And what i can see, you only draw one mesh, and thats the next one you try to load.
So you have to do something like this for drawing all meshes :
[code]
void Draw()
{
// select which vertex buffer to display
const UINT stride = sizeof(Mesh::VERTEX);
const UINT offset = 0;
static const itSize = idCount;
// select which primtive type we are using
devcon->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
for(unsigned int i = 0; i<itSize; ++i)
{
devcon->IASetVertexBuffers(0, 1, &MESH->model[i].pVBuffer, &stride, &offset);
devcon->IASetIndexBuffer(MESH->model[i].pIBuffer, DXGI_FORMAT_R32_UINT, 0);
devcon->UpdateSubresource(pCBuffer, 0, 0, &cBuffer, 0, 0);
devcon->PSSetShaderResources(0, 1, &MESH->model[idCount].pTexture);
devcon->DrawIndexed(MESH->model[idCount].totalVertices, 0, 0);
}
}
[/code]




And as a edit, in your mesh struct,
you can save memory and having, scale, translation and rotation into vectors. and then multiply then into a world matrix. instead of having a matrix for each component.
Or well, thats how i would do it. Edited by Tordin

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Tordin.....YOU'RE AWESOME! This has helped alot! I changed some of the coding though However, you're right about the matrix's truned into Vectors. I'll change that soon. THanks Ripits and thanks Tordin.

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