Shaders and Directx11 compilation in c++ - c++

Question

I am trying to create a Directx 11 program using c++ . The code used to work before I added Normal to the code .Now it doesnt compile the shader at all .It keeps giving me access Violation 0X0000 Error.
I tried using d3dErrorBlolb but wasnt very helpful.The problem seems to lie in this part of the code.
void InitPipeline(HWND hwnd)
{
ID3D10Blob * BVS = 0,*BPS = 0;
ID3D10Blob * BErrorVS,*BErrorPs;
HRESULT hr1 = D3DX11CompileFromFile(L"Test.fx",0,0,"VS","vs_4_0",0,0,0,&BVS,&BErrorVS,0);
HRESULT hr = D3DX11CompileFromFile(L"Test.fx",0,0,"PS","ps_4_0",0,0,0,&BPS,&BErrorPs,0);
if(FAILED(hr))
{
printf("Error %08X %5s\n",hr,(char*)BErrorVS);
MessageBox(hwnd,L"Pixel shader not created ",L"",0);
}
if(FAILED(hr1))
{ MessageBox(hwnd,L"Vertex shader not created ",L"",0);}
dev->CreateVertexShader(BVS->GetBufferPointer(),BVS->GetBufferSize(),0,&BoxVShader);
dev->CreatePixelShader(BPS->GetBufferPointer(),BPS->GetBufferSize(),0,&BoxPixelShader);
// create the input layout object
D3D11_INPUT_ELEMENT_DESC ied[] =
{
{"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}
// {"COLOR", 0, DXGI_FORMAT_R32G32B32A32_FLOAT, 0, 24, D3D11_INPUT_PER_VERTEX_DATA, 0}
};
//SecureZeroMemory(&Bin);
dev->CreateInputLayout(ied,2,BVS->GetBufferPointer(),BVS->GetBufferSize(),&BInputLayout);
devcon->VSSetShader(BoxVShader,0,0);
devcon->PSSetShader(BoxPixelShader,0,0);
devcon->IASetInputLayout(BInputLayout);
}
The Test.fx file
ecbuffer ConstantBuffer:register(b0)
{
matrix world;
matrix view;
matrix project;
float3[2] LightDir;
float4[2] LightColor;
}
struct Vout{
float4 pos:SV_POSITION;
float4 normal : NORMAL;
};
Vout VS(float3 pos:POSITION,float3 Norm:NORMAL)
{
Vout vo = (Vout)0;
vo.pos = mul(float4(pos,1),world);
vo.pos = mul(vo.pos,view);
vo.pos = mul(vo.pos,project);
vo.normal = mul(float4(Norm,1),world);
return vo;
}
float4 PS(float4 pos:SV_POSITION,float4 normal:NORMAL):SV_TARGET
{
float4 col;
for(int i=0; i < 2;++i)
{
col += saturate(dot(normal,LightDir[i])) * LightColor[i] ;
}
return col;
}
Can anyone please be kind enough to help me out...
If possible please do explain why this keeps happening always..What am I doing wrong here
Please do help me.I desperately need to solve this problem....
Thank you...

Answer 1

While compiling HLSL at runtime is nice for learning and iteration, it's actually a lot easier to debug the HLSL by compiling it with the command-line:
fxc test.fx /Tvs_4_0 /EVS and fxc test.fx /Tps_4_0 /EPS
The second fails because you failed to set the initial value for col in the Pixel Shader:
test.fx(40,25-47): warning X3206: 'dot': implicit truncation of vector type
test.fx(40,9-64): error X4000: variable 'col' used without having been completely initialized
compilation failed; no code produced
The fix is trivial:
float4 PS(float4 pos:SV_POSITION,float4 normal:NORMAL):SV_TARGET
{
float4 col = 0;
for(int i=0; i < 2;++i)
{
col += saturate(dot(normal,LightDir[i])) * LightColor[i] ;
}
return col;
}
You are getting an AV because you have the wrong handling of the failed compiler output, you forgot to initialize both BErrorVS and BErrorPS to null, and you are trying to output BErrorVS when the VS succeeded, but the PS failed. It should be:
if(FAILED(hr))
{
printf("Error %08X %5s\n",hr,(char*)BErrorPS->GetBufferPointer());
MessageBox(hwnd,L"Pixel shader not created ",L"",0);
}
Also you should remember that BErrorVS and BErrorPS can be set to a non-null value even if SUCCEEDED(hr)) since it can be reporting only non-fatal warnings.
See HLSL, FXC, and D3DCompile