Using multiple textures in Direct3D11 with CG - c

Question

I want to use a 3D texture and a 1D color map in Direct3D11/CG Here is the simple pixel shader code:
struct fourDf_In {
float4 position : POSITION;
float3 texCoord : TEXCOORD0;
};
struct fourDf_Out {
float4 color : COLOR;
};
fourDf_Out fourDf ( fourDf_In input,
const uniform sampler1D ColorMap : TEX0,
const uniform sampler3D USTexture : TEX1
)
{
fourDf_Out o, o1;
float tmp;
tmp = tex3D(USTexture, input.texCoord).r;
o.color = tex1D(ColorMap, tmp); // 2 samplers not working
return o;
}
And this my initialization code:
ID3D11Device *g_pDevice = NULL;
ID3D11Texture1D *myColorMap = NULL;
ID3D11Texture3D *myUSTexture = NULL;
ColorMap = cgGetNamedParameter(myCgFragmentProgram, "ColorMap");
cgD3D11SetTextureParameter( ColorMap, myColorMap );
cgD3D11SetSamplerStateParameter( ColorMap, NULL ); // NULL == default states
USTexture = cgGetNamedParameter(myCgFragmentProgram, "USTexture");
cgD3D11SetTextureParameter(USTexture, myUSTexture);
cgD3D11SetSamplerStateParameter( USTexture, NULL); // NULL == default states
// ---- 1D ColorMap
D3D11_TEXTURE1D_DESC tx1d;
tx1d.Width = ColorMapLength;
tx1d.MipLevels = 1;
tx1d.ArraySize = 1;
tx1d.Format = DXGI_FORMAT_R8G8B8A8_UNORM; //DXGI_FORMAT_R8G8B8A8_UINT; //DXGI_FORMAT_R8G8B8A8_UNORM; //
tx1d.Usage = D3D11_USAGE_DEFAULT;
tx1d.BindFlags = D3D11_BIND_SHADER_RESOURCE;
tx1d.CPUAccessFlags = 0;
tx1d.MiscFlags = 0;
srd = {0};
srd.pSysMem = ColorMapArray;
srd.SysMemPitch = 0; // ColorMapLength*4;
srd.SysMemSlicePitch = 0; //ColorMapLength*4;
hr = g_pDevice->CreateTexture1D(&tx1d, &srd, &myColorMap);
if( hr != S_OK )
return hr;
// ---- 3D texture
D3D11_TEXTURE3D_DESC tx3d;
tx3d.Width = iWidth;
tx3d.Height = iHeight;
tx3d.Depth = iDepth;
tx3d.MipLevels = 1;
tx3d.Format = DXGI_FORMAT_R8_UNORM; //DXGI_FORMAT_R8_UNORM; //;
tx3d.Usage = D3D11_USAGE_DYNAMIC;
tx3d.BindFlags = D3D11_BIND_SHADER_RESOURCE;
tx3d.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
tx3d.MiscFlags = 0;
hr = g_pDevice->CreateTexture3D(&tx3d, NULL, &myUSTexture);
if( hr != S_OK )
return hr;
The 3D and 1D textures work separately, but not together. i.e feeding the output of 3D texture to the 1D ColourMap fails and the image is totally black. I suspect it has something to do with initializing multiple texture units (TEX0, TEX1)?? How do I get to use 2 textures in CG with Direct3D?

Answer 1

Found that in the pixel shader code TEX0 and TEX1 were depreciated keywords and both were pointing to the same sampler.
The correct syntax appears to be:
const uniform sampler1D ColorMap : TEXUNIT0,
const uniform sampler3D USTexture : TEXUNIT1
CG is obsolete and I recommend removing this dependency and port it entirely into DirectX/HLSL.
Ravi Ganesh