CommandSignature.cpp

///////////////////////////////////////////////////////////////////////////////////////////////////
//
// CommandSignature.cpp
//
///////////////////////////////////////////////////////////////////////////////////////////////////

///////////////////////////////////////////////////////////////////////////////////////////////////
// Header section

#include "CommandSignature.h"
#include "../D3DRenderer.h"

///////////////////////////////////////////////////////////////////////////////////////////////////
// Declaration section

using namespace Engine;

///////////////////////////////////////////////////////////////////////////////////////////////////
// Definition section

/// <summary>
/// Initialize Direct3D 12 command signature object
/// </summary>
/// <param name="device">Direct3D 12 device</param>
/// <param name="stride">Record stride</param>
/// <param name="rootSignature">Root signature for this command signature</param>
void CommandSignature::Init(ID3D12Device* device, size_t stride, RootSignature* rootSignature)
{
    if (mFinalized)
    {
        return;
    }

    unsigned int byteStride = 0;
    bool requiresRootSignature = false;

    for (unsigned int i = 0; i < mNumParameters; i++)
    {
        switch (mParameters[i].Get().Type)
        {
        case D3D12_INDIRECT_ARGUMENT_TYPE_DRAW:
            byteStride += sizeof(D3D12_DRAW_ARGUMENTS);
            break;

        case D3D12_INDIRECT_ARGUMENT_TYPE_DRAW_INDEXED:
            byteStride += sizeof(D3D12_DRAW_INDEXED_ARGUMENTS);
            break;

        case D3D12_INDIRECT_ARGUMENT_TYPE_DISPATCH:
            byteStride += sizeof(D3D12_DISPATCH_ARGUMENTS);
            break;

        case D3D12_INDIRECT_ARGUMENT_TYPE_VERTEX_BUFFER_VIEW:
            byteStride += sizeof(D3D12_VERTEX_BUFFER_VIEW);
            break;

        case D3D12_INDIRECT_ARGUMENT_TYPE_INDEX_BUFFER_VIEW:
            byteStride += sizeof(D3D12_INDEX_BUFFER_VIEW);
            break;

        case D3D12_INDIRECT_ARGUMENT_TYPE_CONSTANT:
            byteStride += mParameters[i].Get().Constant.Num32BitValuesToSet * 4;
            requiresRootSignature = true;
            break;

        case D3D12_INDIRECT_ARGUMENT_TYPE_CONSTANT_BUFFER_VIEW:
        case D3D12_INDIRECT_ARGUMENT_TYPE_SHADER_RESOURCE_VIEW:
        case D3D12_INDIRECT_ARGUMENT_TYPE_UNORDERED_ACCESS_VIEW:
            byteStride += 8;
            requiresRootSignature = true;
            break;

        case D3D12_INDIRECT_ARGUMENT_TYPE_DISPATCH_MESH:
            byteStride += sizeof(D3D12_DISPATCH_ARGUMENTS);
            requiresRootSignature = true;
            break;
        }
    }

    byteStride = (unsigned int)stride;

    D3D12_COMMAND_SIGNATURE_DESC desc;
    desc.ByteStride = byteStride;
    desc.NumArgumentDescs = mNumParameters;
    desc.pArgumentDescs = (const D3D12_INDIRECT_ARGUMENT_DESC*)mParameters;
    desc.NodeMask = 1;

    //ID3DBlob* outBlob;
    //ID3DBlob* errorBlob;

    ID3D12RootSignature* rootSignatureD3D = rootSignature ? rootSignature->Get() : nullptr;
    if (requiresRootSignature)
    {
        // TODO: if rootSignature is null, log!
    }
    else
    {
        rootSignatureD3D = nullptr;
    }

    device->CreateCommandSignature(&desc, rootSignatureD3D, __uuidof(ID3D12CommandSignature), (void**)&mSignature);
    mSignature->SetName(L"CommandSignature");

    mFinalized = true;
}

/// <summary>
/// Initialize Direct3D 12 command signature object
/// </summary>
/// <param name="renderer">Direct3D 12 renderer</param>
/// <param name="stride">Record stride</param>
/// <param name="rootSignature">Root signature for this command signature</param>
void CommandSignature::Init(D3DRenderer* renderer, size_t stride, RootSignature* rootSignature)
{
    Init(renderer->GetDevice(), stride, rootSignature);
}