tiny_obj_loader 到 Direct3D 顶点缓冲区和索引缓冲区数组答案

【问题标题】：tiny_obj_loader to Direct3D Vertex Buffer and Index Buffer Arraystiny_obj_loader 到 Direct3D 顶点缓冲区和索引缓冲区数组
【发布时间】：2018-11-17 20:45:36
【问题描述】：

我在pSwapChain->Present() 期间遇到了一个我无法调试的错误。

我正在使用 DXUT 示例并构建一个 OBJ 加载器。为此，我从 SDKmesh 类复制功能并使用 tiny_obj_loader 类加载 obj 文件。

我得到的错误是

Exception thrown at 0x00007FF89DC288A8 (nvwgf2umx.dll) in test.exe: 0xC0000005: Access violation reading location 0xFFFFFFFFFFFFFFFF.

我的导入obj的测试代码如下。

我确实意识到我正在愚蠢地将 tiny_obj_loader 结构转换为 ID3D11Buffers。但我希望 tiny_obj_loader 至少尝试复制这些缓冲区结构。还是我需要一个更好的 obj 导入库？谁能推荐一款兼容 DirectX 的？

bool DXUTModel::LoadOBJ(std::string object_file)
{
    IModel::LoadOBJ(object_file);

    int num_vertices = attrib.vertices.size();
    int num_indices = shapes[0].mesh.indices.size();

    g_Mesh11.m_ppVertices = (BYTE**)&attrib.vertices;
    g_Mesh11.m_ppIndices = (BYTE**)&shapes[0].mesh.indices;

    g_Mesh11.m_pMaterialArray = new SDKMESH_MATERIAL;
    std::wstring strPath = L"Media\\Base_skin.dds";
    if (FAILED(DXUTGetGlobalResourceCache().CreateTextureFromFile(dxCtr->m_pDevice, dxCtr->m_pImmediateContext, strPath.c_str(), &g_Mesh11.m_pMaterialArray->pDiffuseRV11,true)))
        g_Mesh11.m_pMaterialArray->pDiffuseRV11 = (ID3D11ShaderResourceView*)ERROR_RESOURCE_VALUE;

    //Set Vertex Buffer Array
    g_Mesh11.m_pMeshArray = new SDKMESH_MESH;
    g_Mesh11.m_pVertexBufferArray = new SDKMESH_VERTEX_BUFFER_HEADER;
    g_Mesh11.m_pMeshArray[0].VertexBuffers[0] = 0;
    g_Mesh11.m_pVertexBufferArray[g_Mesh11.m_pMeshArray[0].VertexBuffers[0]].pVB11 = (ID3D11Buffer*)&attrib.vertices;
    g_Mesh11.m_pVertexBufferArray[g_Mesh11.m_pMeshArray[0].VertexBuffers[0]].StrideBytes = 32;

    //Set Index Buffer array
    g_Mesh11.m_pMeshArray[0].IndexBuffer = 0;
    g_Mesh11.m_pIndexBufferArray = new SDKMESH_INDEX_BUFFER_HEADER;
    g_Mesh11.m_pIndexBufferArray[g_Mesh11.m_pMeshArray[0].IndexBuffer].IndexType = IT_16BIT;
    g_Mesh11.m_pIndexBufferArray[g_Mesh11.m_pMeshArray[0].IndexBuffer].pIB11 = (ID3D11Buffer*)&shapes[0].mesh.indices;

    //Set subset
    SDKMESH_SUBSET v_subset;
    v_subset.MaterialID = 0;
    v_subset.PrimitiveType = PT_TRIANGLE_LIST;
    v_subset.IndexCount = shapes[0].mesh.indices.size();
    v_subset.VertexCount = attrib.vertices.size();
    v_subset.VertexStart = 0;
    v_subset.IndexStart = 0;
    g_Mesh11.m_pMeshArray[0].pSubsets = new UINT;
    g_Mesh11.m_pMeshArray[0].pSubsets[0] = 0;
    g_Mesh11.m_pMeshArray[0].NumSubsets = 1;
    g_Mesh11.m_pSubsetArray = new SDKMESH_SUBSET;
    g_Mesh11.m_pSubsetArray[g_Mesh11.m_pMeshArray[0].pSubsets[0]] = v_subset;
    return true;
}

【问题讨论】：

我不知道tiny_obj_loader 做了什么，但所有这些随机投射只是腿部的直射。从变量名称来看，您需要为网格顶点和使用ID3D11Device::CreateBuffer 从该库获得的索引创建 DirectX 缓冲区。您还需要确保加载的顶点与您使用的着色器兼容。
如果您要求图书馆的推荐，这个问题是题外话。如果您正在为您的问题寻求帮助，则可能不是。最好放弃对更好/其他库的查询，以便为详细说明您的问题的信息腾出空间（例如调用堆栈）。
谢谢，我刚刚意识到我无法将 CPU 内存转换为 GPU 缓冲区。

标签： c++ winapi visual-studio-2015 directx

【解决方案1】：

我似乎已经修复了最初的错误替换：

//g_Mesh11.m_pVertexBufferArray[g_Mesh11.m_pMeshArray[0].VertexBuffers[0]].pVB11 = (ID3D11Buffer*)&attrib.vertices;
//g_Mesh11.m_pIndexBufferArray[g_Mesh11.m_pMeshArray[0].IndexBuffer].pIB11 = (ID3D11Buffer*)&shapes[0].mesh.indices;

与：

D3D11_BUFFER_DESC bufferDesc;
bufferDesc.ByteWidth = (UINT)(attrib.vertices.size()*4);
bufferDesc.Usage = D3D11_USAGE_DEFAULT;
bufferDesc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
bufferDesc.CPUAccessFlags = 0;
bufferDesc.MiscFlags = 0;
D3D11_SUBRESOURCE_DATA InitData;
InitData.pSysMem = &attrib.vertices[0];
dxCtr->m_pDevice->CreateBuffer(&bufferDesc, &InitData, &g_Mesh11.m_pVertexBufferArray[g_Mesh11.m_pMeshArray[0].VertexBuffers[0]].pVB11);
g_Mesh11.m_pVertexBufferArray[g_Mesh11.m_pMeshArray[0].VertexBuffers[0]].StrideBytes = 32;
g_Mesh11.m_pVertexBufferArray[g_Mesh11.m_pMeshArray[0].VertexBuffers[0]].SizeBytes = attrib.vertices.size() * 4;

//Set Index Buffer array
g_Mesh11.m_pMeshArray[0].IndexBuffer = 0;
g_Mesh11.m_pIndexBufferArray = new SDKMESH_INDEX_BUFFER_HEADER;
g_Mesh11.m_pIndexBufferArray[g_Mesh11.m_pMeshArray[0].IndexBuffer].IndexType = IT_16BIT;
D3D11_BUFFER_DESC bufferDesc2;
bufferDesc2.ByteWidth = (UINT)(shapes[0].mesh.indices.size());
bufferDesc2.Usage = D3D11_USAGE_DEFAULT;
bufferDesc2.BindFlags = D3D11_BIND_INDEX_BUFFER;
bufferDesc2.CPUAccessFlags = 0;
bufferDesc2.MiscFlags = 0;
D3D11_SUBRESOURCE_DATA InitData2;
InitData2.pSysMem = &shapes[0].mesh.indices[0];
dxCtr->m_pDevice->CreateBuffer(&bufferDesc, &InitData2, &g_Mesh11.m_pIndexBufferArray[g_Mesh11.m_pMeshArray[0].IndexBuffer].pIB11);
g_Mesh11.m_pIndexBufferArray[g_Mesh11.m_pMeshArray[0].IndexBuffer].SizeBytes = shapes[0].mesh.indices.size();

它在画一些东西，它不漂亮，但它有质感。当我让它正常工作时会发布代码

【讨论】：