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OpenGL SamplerState in code or HLSL?

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Hey, going from OpenGL 4 to DX11, and am currently stuck at uploading some diffuse textures to pixel shader.

 

1) I've seen code samples where you create a sampler object (kinda like in OpenGL?) in D3D code and I've also seen sampler types defined explicitly in the HLSL shader. Is there any reason to pick one over the other?

 

2) How are mipmaps created in DX11? In OpenGL, theres a function specifically generate mipmaps for a texture, and then you can set sampler parameters to use mipmaps when sampling the textures. How is this done in DX11?

Edited by KaiserJohan

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OK, I tried it as you suggested and had a look at the DirectTex code, but something must be wrong with the mipmaps. I have a large rectangular floor with a checker-like texture over it, but instead I get the following:

 

mipmap.jpg

 

 

Any reason why this could be?

 

I have the following to build the texture:

 

    DX11Texture::DX11Texture(ID3D11Device* device, ID3D11DeviceContext* context, const std::vector<uint8_t>& textureData, uint32_t textureWidth, uint32_t textureHeight, TextureType textureType, Logger& logger) :
        mTexture(nullptr), mShaderResourceView(nullptr), mTextureID(gNextTextureID++), mTextureType(textureType)
    {
        // create texture
        D3D11_TEXTURE2D_DESC textureDesc;
        ZeroMemory(&textureDesc, sizeof(D3D11_TEXTURE2D_DESC));
        textureDesc.Width = textureWidth;
        textureDesc.Height = textureHeight;
        textureDesc.ArraySize = 1;
        textureDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
        textureDesc.SampleDesc.Count = 1;
        textureDesc.Usage = D3D11_USAGE_DEFAULT;
        textureDesc.BindFlags = D3D11_BIND_SHADER_RESOURCE | D3D11_BIND_RENDER_TARGET;
        textureDesc.MiscFlags = D3D11_RESOURCE_MISC_GENERATE_MIPS;
        DXCALL(device->CreateTexture2D(&textureDesc, NULL, &mTexture));


        D3D11_SHADER_RESOURCE_VIEW_DESC srvDesc;
        ZeroMemory(&srvDesc, sizeof(D3D11_SHADER_RESOURCE_VIEW_DESC));
        srvDesc.Format = textureDesc.Format;
        srvDesc.ViewDimension = D3D11_SRV_DIMENSION_TEXTURE2D;
        srvDesc.Texture2D.MipLevels = -1;
        DXCALL(device->CreateShaderResourceView(mTexture, &srvDesc, &mShaderResourceView));


        // mip-level 0 data
        uint32_t sizeWidth = textureWidth * sizeof(uint8_t);
        context->UpdateSubresource(mTexture, 0, NULL, &textureData.at(0), sizeWidth, sizeWidth * textureHeight);


        context->GenerateMips(mShaderResourceView);
    }

Here's the sampler used:

 

        // create texture sampler
        D3D11_SAMPLER_DESC samplerDesc;
        ZeroMemory(&samplerDesc, sizeof(D3D11_SAMPLER_DESC));
        samplerDesc.Filter = D3D11_FILTER_ANISOTROPIC;
        samplerDesc.AddressU = D3D11_TEXTURE_ADDRESS_WRAP;
        samplerDesc.AddressV = D3D11_TEXTURE_ADDRESS_WRAP;
        samplerDesc.AddressW = D3D11_TEXTURE_ADDRESS_WRAP;
        samplerDesc.MaxAnisotropy = mAnisotropicFiltering;
        samplerDesc.ComparisonFunc = D3D11_COMPARISON_ALWAYS;
        samplerDesc.MaxLOD = D3D11_FLOAT32_MAX;
        DXCALL(mDevice->CreateSamplerState(&samplerDesc, &mTextureSampler));

Any ideas? Looks correct to me

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You're calculating your pitch incorrectly. You're using a R8G8B8A8 format, so the size of each texel should be textureWidth * sizeof(uint8_t) * 4. You can also pass a value of 0 for "SrcDepthPitch", since you're not using a 3D texture.

 

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Hmm... tried that, it now looks like this - one half is now not textured:

 

mipmap2.jpg

 

 

The alterations being:

        uint32_t sizeWidth = textureWidth * sizeof(uint8_t) * 4;
        context->UpdateSubresource(mTexture, 0, NULL, &textureData.at(0), sizeWidth, 0);

        context->GenerateMips(mShaderResourceView);

Must be something else?

Edited by KaiserJohan

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Hmm... tried that, it now looks like this - one half is now not textured:

 

mipmap2.jpg

 

 

The alterations being:

        uint32_t sizeWidth = textureWidth * sizeof(uint8_t) * 4;
        context->UpdateSubresource(mTexture, 0, NULL, &textureData.at(0), sizeWidth, 0);

        context->GenerateMips(mShaderResourceView);

Must be something else?

Just trying to take a swing in the ball park---try doing

context->UpdateSubresource(mTexture, 0, NULL, &textureData.at(0), textureHeight * sizeWidth, 0);

See what you get? You may be getting the texture width but not the whole image itself - the way it looks like. I had trouble viewing your image from this site.

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Hmm... tried that, it now looks like this - one half is now not textured:

 

mipmap2.jpg

 

 

The alterations being:

        uint32_t sizeWidth = textureWidth * sizeof(uint8_t) * 4;
        context->UpdateSubresource(mTexture, 0, NULL, &textureData.at(0), sizeWidth, 0);

        context->GenerateMips(mShaderResourceView);

Must be something else?

Just trying to take a swing in the ball park---try doing

context->UpdateSubresource(mTexture, 0, NULL, &textureData.at(0), textureHeight * sizeWidth, 0);

See what you get? You may be getting the texture width but not the whole image itself - the way it looks like. I had trouble viewing your image from this site.

 

 

It throws me an "Access violation reading location" exception. Though I can confirm textureData.size=65536 so thats strange?

 

Also, theres nothing with the way I create the two vertex buffers (one of vertices, one for texcoords)?

    DX11Mesh::DX11Mesh(ID3D11Device* device, const BYTE* shaderBytecode, const uint32_t shaderBytecodeSize, const std::vector<float>& vertexData, const std::vector<float>& normalData,
        const std::vector<float>& texCoords, const std::vector<float>& tangents, const std::vector<float>& bitangents, const std::vector<uint32_t>& indexData, Logger& logger) 
        : mLogger(logger), mMeshID(gNextMeshID++), mNumIndices(indexData.size()), mVertexBuffer(nullptr), mTexcoordBuffer(nullptr), mIndexBuffer(nullptr), mInputLayout(nullptr)
    {
        // vertex buffer
        D3D11_BUFFER_DESC bufferDescription;
        ZeroMemory(&bufferDescription, sizeof(D3D11_BUFFER_DESC));
        bufferDescription.Usage = D3D11_USAGE_IMMUTABLE;
        bufferDescription.ByteWidth = vertexData.size() * sizeof(float);
        bufferDescription.BindFlags = D3D11_BIND_VERTEX_BUFFER;

        D3D11_SUBRESOURCE_DATA initData;
        ZeroMemory(&initData, sizeof(D3D11_SUBRESOURCE_DATA));
        initData.pSysMem = &vertexData.at(0);

        DXCALL(device->CreateBuffer(&bufferDescription, &initData, &mVertexBuffer));

        // texcoord buffer
        ZeroMemory(&bufferDescription, sizeof(D3D11_BUFFER_DESC));
        bufferDescription.Usage = D3D11_USAGE_IMMUTABLE;
        bufferDescription.ByteWidth = texCoords.size() * sizeof(float);
        bufferDescription.BindFlags = D3D11_BIND_VERTEX_BUFFER;

        ZeroMemory(&initData, sizeof(D3D11_SUBRESOURCE_DATA));
        initData.pSysMem = &texCoords.at(0);

        DXCALL(device->CreateBuffer(&bufferDescription, &initData, &mTexcoordBuffer));

        // index buffer
        ZeroMemory(&bufferDescription, sizeof(D3D11_BUFFER_DESC));
        bufferDescription.Usage = D3D11_USAGE_IMMUTABLE;
        bufferDescription.ByteWidth = indexData.size() * sizeof(uint32_t);
        bufferDescription.BindFlags = D3D11_BIND_INDEX_BUFFER;

        ZeroMemory(&initData, sizeof(D3D11_SUBRESOURCE_DATA));
        initData.pSysMem = &indexData.at(0);

        DXCALL(device->CreateBuffer(&bufferDescription, &initData, &mIndexBuffer));

        // input layout
        D3D11_INPUT_ELEMENT_DESC inputDescription[2];
        ZeroMemory(&inputDescription, sizeof(D3D11_INPUT_ELEMENT_DESC) * 2);
        inputDescription[0].SemanticName = "POSITION";
        inputDescription[0].SemanticIndex = 0;
        inputDescription[0].Format = DXGI_FORMAT_R32G32B32_FLOAT;
        inputDescription[0].InputSlot = 0;
        inputDescription[0].AlignedByteOffset = 0;
        inputDescription[0].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
        inputDescription[0].InstanceDataStepRate = 0;
        inputDescription[1].SemanticName = "TEXCOORD";
        inputDescription[1].SemanticIndex = 0;
        inputDescription[1].Format = DXGI_FORMAT_R32G32_FLOAT;
        inputDescription[1].InputSlot = 0;
        inputDescription[1].AlignedByteOffset = 12;
        inputDescription[1].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
        inputDescription[1].InstanceDataStepRate = 0;

        DXCALL(device->CreateInputLayout(inputDescription, 2, shaderBytecode, shaderBytecodeSize, &mInputLayout));
    }

And this is how I bind them for drawing:

    void DX11Mesh::Draw(ID3D11DeviceContext* context)
    {
        uint32_t vertexSize = sizeof(float) * 3, texcoordSize = sizeof(float) * 2;
        uint32_t offset = 0;

        context->IASetVertexBuffers(0, 1, &mVertexBuffer, &vertexSize, &offset);
        context->IASetVertexBuffers(1, 1, &mTexcoordBuffer, &texcoordSize, &offset);
        context->IASetIndexBuffer(mIndexBuffer, DXGI_FORMAT_R32_UINT, 0);
        context->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
        context->IASetInputLayout(mInputLayout);

        context->DrawIndexed(mNumIndices, 0, 0);
    }



The actual texcoordinates are legit; I used them in OpenGL so unless the texture sampling is different (I think not) then it should be just fine...?

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Since you're using a second vertex stream, the input layout should reflect that:
  inputDescription[1].InputSlot = 1;
  inputDescription[1].AlignedByteOffset = 0;
Such troubles are better analyzed with a graphics debugger where you can see if your texture upload succeeded and if your vertices are correct.

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Since you're using a second vertex stream, the input layout should reflect that:

  inputDescription[1].InputSlot = 1;
  inputDescription[1].AlignedByteOffset = 0;
Such troubles are better analyzed with a graphics debugger where you can see if your texture upload succeeded and if your vertices are correct.

 

 

Thats it. Thanks.

 

The result is not as good as I hoped it to be, even with anisotropic filtering set to 16. Here's an example:

 

 

ansitropic.jpg

 

In the background you see its very blurry. Is there any way to get better visuals?

Edited by KaiserJohan

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At the grazing angles the undersampling is going to be very extreme, and even 16 samples won't be enough. So you'll get either aliasing artifacts, or blurring due to the hardware using a lower-resolution mip level. You'll also get issues from the hardware using various approximations and "optimizations". Usually you can turn these off in the driver control panel. Typically they'll have some sort of "quality" slider that you can turn up to get better filtering results at the cost of additional performance.

Edited by MJP

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MJP is right and also It looks great by the way! There's different sampler states you can also use if you want a texture rendered differently like point sampling amongst others. What are your settings for your device upon initialization? My sample count is 8 and sample quality is 32 getting the 8x MSAA and I'm hooking it where the player can change the settings inside the options menu.. However, your texture suppose to look like that do to the furtherest edge away from the camera gets blurred. Let me show you an example of mine from my editor.

 

If you can see the checkboard texture is blurred at the end? It's using the same sampler like yours but the texture isn't streamed like yours.  So, you're looks normal like it should be.

 

Awesome job getting it solved!

 

Also, I have a hard time viewing your images so time so I have to go into Tamper Data to actually get the link - you can post images easily on here. Just click on attach files on the bottom of the reply. If you don't see the attach files above the add reply - click on Advanced Reply Options. Just helping out the next time whenever you post images.

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Sorry for all the persistant questions, there are just a couple of things left I need to clear up.

 

1) So there really is no way to achieve better visuals than the 16x anisotropic filtering when sampling textures? The image I posted still looks really muddled.

 

2) I create the textures with the usage flag D3D11_USAGE_DEFAULT. This dosn't feel optimal considering its a static texture, but I need it due to mipmap generation. Is there any performance issues with that usage versus D3D11_USAGE_IMMUTABLE, and is there any easy way of fixing it?

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