DirectX 10 Primitive is not displayed - directx

Question

I am trying to write my first DirectX 10 program that displays a triangle. Everything compiles fine, and the render function is called, since the background changes to black. However, the triangle I'm trying to draw with a triangle strip primitive is not displayed at all.
The Initialization function:
bool InitDirect3D(HWND hWnd, int width, int height)
{
//****** D3DDevice and SwapChain *****//
DXGI_SWAP_CHAIN_DESC swapChainDesc;
ZeroMemory(&swapChainDesc, sizeof(swapChainDesc));
swapChainDesc.BufferCount = 1;
swapChainDesc.BufferDesc.Width = width;
swapChainDesc.BufferDesc.Height = height;
swapChainDesc.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
swapChainDesc.BufferDesc.RefreshRate.Numerator = 60;
swapChainDesc.BufferDesc.RefreshRate.Denominator = 1;
swapChainDesc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
swapChainDesc.OutputWindow = hWnd;
swapChainDesc.SampleDesc.Count = 1;
swapChainDesc.SampleDesc.Quality = 0;
swapChainDesc.Windowed = TRUE;
if (FAILED(D3D10CreateDeviceAndSwapChain( NULL,
D3D10_DRIVER_TYPE_HARDWARE,
NULL,
0,
D3D10_SDK_VERSION,
&swapChainDesc,
&pSwapChain,
&pD3DDevice)))
return fatalError(TEXT("Hardware does not support DirectX 10!"));
//***** Shader *****//
if (FAILED(D3DX10CreateEffectFromFile( TEXT("basicEffect.fx"),
NULL, NULL,
"fx_4_0",
D3D10_SHADER_ENABLE_STRICTNESS,
0,
pD3DDevice,
NULL,
NULL,
&pBasicEffect,
NULL,
NULL)))
return fatalError(TEXT("Could not load effect file!"));
pBasicTechnique = pBasicEffect->GetTechniqueByName("Render");
pViewMatrixEffectVariable = pBasicEffect->GetVariableByName( "View" )->AsMatrix();
pProjectionMatrixEffectVariable = pBasicEffect->GetVariableByName( "Projection" )->AsMatrix();
pWorldMatrixEffectVariable = pBasicEffect->GetVariableByName( "World" )->AsMatrix();
//***** Input Assembly Stage *****//
D3D10_INPUT_ELEMENT_DESC layout[] =
{
{"POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D10_INPUT_PER_VERTEX_DATA, 0},
{"COLOR", 0, DXGI_FORMAT_R32G32B32A32_FLOAT, 0, 12, D3D10_INPUT_PER_VERTEX_DATA, 0}
};
UINT numElements = 2;
D3D10_PASS_DESC PassDesc;
pBasicTechnique->GetPassByIndex(0)->GetDesc(&PassDesc);
if (FAILED( pD3DDevice->CreateInputLayout( layout,
numElements,
PassDesc.pIAInputSignature,
PassDesc.IAInputSignatureSize,
&pVertexLayout)))
return fatalError(TEXT("Could not create Input Layout."));
pD3DDevice->IASetInputLayout( pVertexLayout );
//***** Vertex buffer *****//
UINT numVertices = 100;
D3D10_BUFFER_DESC bd;
bd.Usage = D3D10_USAGE_DYNAMIC;
bd.ByteWidth = sizeof(vertex) * numVertices;
bd.BindFlags = D3D10_BIND_VERTEX_BUFFER;
bd.CPUAccessFlags = D3D10_CPU_ACCESS_WRITE;
bd.MiscFlags = 0;
if (FAILED(pD3DDevice->CreateBuffer(&bd, NULL, &pVertexBuffer)))
return fatalError(TEXT("Could not create vertex buffer!"));;
UINT stride = sizeof(vertex);
UINT offset = 0;
pD3DDevice->IASetVertexBuffers( 0, 1, &pVertexBuffer, &stride, &offset );
//***** Rasterizer *****//
// Set the viewport
viewPort.Width = width;
viewPort.Height = height;
viewPort.MinDepth = 0.0f;
viewPort.MaxDepth = 1.0f;
viewPort.TopLeftX = 0;
viewPort.TopLeftY = 0;
pD3DDevice->RSSetViewports(1, &viewPort);
D3D10_RASTERIZER_DESC rasterizerState;
rasterizerState.CullMode = D3D10_CULL_NONE;
rasterizerState.FillMode = D3D10_FILL_SOLID;
rasterizerState.FrontCounterClockwise = true;
rasterizerState.DepthBias = false;
rasterizerState.DepthBiasClamp = 0;
rasterizerState.SlopeScaledDepthBias = 0;
rasterizerState.DepthClipEnable = true;
rasterizerState.ScissorEnable = false;
rasterizerState.MultisampleEnable = false;
rasterizerState.AntialiasedLineEnable = true;
ID3D10RasterizerState* pRS;
pD3DDevice->CreateRasterizerState(&rasterizerState, &pRS);
pD3DDevice->RSSetState(pRS);
//***** Output Merger *****//
// Get the back buffer from the swapchain
ID3D10Texture2D *pBackBuffer;
if (FAILED(pSwapChain->GetBuffer(0, __uuidof(ID3D10Texture2D), (LPVOID*)&pBackBuffer)))
return fatalError(TEXT("Could not get back buffer."));
// create the render target view
if (FAILED(pD3DDevice->CreateRenderTargetView(pBackBuffer, NULL, &pRenderTargetView)))
return fatalError(TEXT("Could not create the render target view."));
// release the back buffer
pBackBuffer->Release();
// set the render target
pD3DDevice->OMSetRenderTargets(1, &pRenderTargetView, NULL);
return true;
}
The render function:
void Render()
{
if (pD3DDevice != NULL)
{
pD3DDevice->ClearRenderTargetView(pRenderTargetView, D3DXCOLOR(0.0f, 0.0f, 0.0f, 0.0f));
//create world matrix
static float r;
D3DXMATRIX w;
D3DXMatrixIdentity(&w);
D3DXMatrixRotationY(&w, r);
r += 0.001f;
//set effect matrices
pWorldMatrixEffectVariable->SetMatrix(w);
pViewMatrixEffectVariable->SetMatrix(viewMatrix);
pProjectionMatrixEffectVariable->SetMatrix(projectionMatrix);
//fill vertex buffer with vertices
UINT numVertices = 3;
vertex* v = NULL;
//lock vertex buffer for CPU use
pVertexBuffer->Map(D3D10_MAP_WRITE_DISCARD, 0, (void**) &v );
v[0] = vertex( D3DXVECTOR3(-1,-1,0), D3DXVECTOR4(1,0,0,1) );
v[1] = vertex( D3DXVECTOR3(0,1,0), D3DXVECTOR4(0,1,0,1) );
v[2] = vertex( D3DXVECTOR3(1,-1,0), D3DXVECTOR4(0,0,1,1) );
pVertexBuffer->Unmap();
// Set primitive topology
pD3DDevice->IASetPrimitiveTopology( D3D10_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP );
//get technique desc
D3D10_TECHNIQUE_DESC techDesc;
pBasicTechnique->GetDesc(&techDesc);
for(UINT p = 0; p < techDesc.Passes; ++p)
{
//apply technique
pBasicTechnique->GetPassByIndex(p)->Apply(0);
//draw
pD3DDevice->Draw(numVertices, 0);
}
pSwapChain->Present(0,0);
}
}

Answer 1

I'm not sure try to set:
pD3DDevice->IASetVertexBuffers( 0, 1, &pVertexBuffer, &stride, &offset );
after you unmap the the buffer. To get something like this:
pVertexBuffer->Unmap();
pD3DDevice->IASetVertexBuffers( 0, 1, &pVertexBuffer, &stride, &offset );
// Set primitive topology
pD3DDevice->IASetPrimitiveTopology( D3D10_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP );
I suspect that locking blows avay buffer binding