Direct2D自定义效果：HLSL多纹理绑定失败求助

我已花费两天时间调试HLSL着色器绑定双纹理的问题：第一个纹理绑定到t0槽并采样返回颜色完全正常，但将同一纹理绑定到t1槽时却始终黑屏。第二个纹理通过OpenCV加载（加载代码已验证可用），第一个纹理是之前着色器运算的结果（也已确认可用）。测试将第一个纹理放到第二个槽同样无法正常显示，因此怀疑是第二个绑定槽本身存在问题，与纹理加载无关。

加载第二个纹理的代码 #

cv::Mat png_image = 
cv::imread("<path to png, also confirmed>", cv::IMREAD_UNCHANGED);
if (!png_image.data)
{
    ASSERT(false);
}
ASSERT(4 == png_image.channels());

// and then the texture data is successfully uploaded to the GPU, 
// this also has to work as the same function has been used multiple times before

自定义Effect代码 #

// BaseCustomEffect extends from  "public ID2D1EffectImpl, public ID2D1DrawTransform" 
// and those implement the "Initialize", "PrepareForRender" and "SetGraph"
class CustomEffect : public BaseCustomEffect
{
private:

    CustomEffect();

public:

    //! Register effect
    static HRESULT Register(ID2D1Factory1* pFactory);
    static HRESULT __stdcall CreateCustomEffect(IUnknown** ppEffectImpl);
};

CustomEffect::CustomEffect()
{
    // BLOT_CustomShader is the compiled binary of the shader (compiled successfully).
    m_shaderBlob = BLOT_CustomShader;
    m_shaderBlobSize = _ARRAYSIZE(BLOT_CustomShader);
    m_shaderGUID = GUID_CustomEffectShader;
}

#define XML(X) TEXT(#X)

HRESULT CustomEffect::Register(ID2D1Factory1* pFactory)
{
    // The inspectable metadata of an effect is defined in XML. This can be passed in from an 
    // external source as well, however for simplicity we just inline the XML.
    PCWSTR pszXml = XML
    (
        <?xml version = '1.0'?>
        <Effect>
            <!--System Properties-->
            <Property name = 'DisplayName' type = 'string' value = 'Custom Effect' />
            <Property name = 'Author' type = 'string' value = '<author>' />
            <Property name = 'Category' type = 'string' value = '<category>' />
            <Property name = 'Description' type = 'string' value = 'Custom effect.' />
            <Inputs minimum = '2' maximum = '2'>
                <Input name = 'Source' />
                <Input name = 'CustomTexture' />
            </Inputs>
        </Effect>
    );

    // Must match name attribute in XML.
    const D2D1_PROPERTY_BINDING bindings[] =
    {
        // this is set here, but not relevant for the problem
        // D2D1_VALUE_TYPE_BINDING(L"Intensity", &SetIntensity, &GetIntensity),
    };

    return pFactory->RegisterEffectFromString(GUID_CustomEffectShader, pszXml, bindings, _ARRAYSIZE(bindings), CreateCustomEffect);
}

HRESULT __stdcall CustomEffect::CreateCustomffect(IUnknown** ppEffectImpl)
{
    *ppEffectImpl = static_cast<ID2D1EffectImpl*>(new CustomEffect());
    return (nullptr == *ppEffectImpl) ? E_OUTOFMEMORY : S_OK;
}

自定义Effect渲染代码 #

inD2DContext->SetTarget(inTargetBmp);
    inD2DContext->BeginDraw();
    inD2DContext->Clear(D2D1::ColorF(D2D1::ColorF::Black, 0.f));
    inConversion.mEffect->SetInputCount(2);
    inConversion.mEffect->SetInput(0, inSourceBmp);
    inConversion.mEffect->SetInput(1, texture->GetData()->GetD2dBitmap());
    inD2DContext->DrawImage(inConversion.mEffect);
    inD2DContext->EndDraw();

HLSL着色器代码 #

#define D2D_INPUT_COUNT 2

Texture2D InputTexture : register(t0); // works, if I sample using the InputSampler, as expected
Texture2D CustomTexture : register(t1); // does not work

SamplerState InputSampler : register(s0);
SamplerState CustomSampler : register(s1);

/*
// not relevant here
cbuffer constants : register(b0)
{
    float Intensity : packoffset(c0);
};
*/

float4 main(
    float4 pos      : SV_POSITION,
    float4 posScene : SCENE_POSITION,
    float2 uv0 : TEXCOORD0
) : SV_Target
{
#if 1
    // works
    //return float4(1, 0, 0, 1);

    // not working
    //return CustomTexture.Sample(InputSampler, uv0);

    // also not working, not expected, as the uvs are now hardcoded
    return CustomTexture.Sample(CustomSampler, float2(0.5f, 0.5f));

    // also not working, this should output the custom texture itself and display it to the screen
    //return CustomTexture.Sample(CustomSampler, uv0);
#else
    // actual shader code, not relevant here
#endif
}

内容的提问来源于stack exchange，提问作者Can