Renderer

CommandQueue

Purpose

• Own a DX12 command queue
• Manage a fixed set of command allocators and command lists
• Execute command lists and signal GPU fences

Properties

• One queue per command list type
• One Command per frame-in-flight
• Each Command owns its allocator and command list

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DescriptorHeapAllocator

DX12 descriptor heap allocation and recycling.

Purpose

• Own a DX12 descriptor heap
• Allocate and recycle descriptor slots
• Provide CPU/GPU descriptor handles

Properties

• One allocator per descriptor heap type (CBV/SRV/UAV, Sampler)
• Fixed-capacity descriptor heap
• Linear allocation with free-list recycling

DescriptorHandle

• One handle per allocated descriptor
• Stores heap index
• Stores CPU handle
• Stores GPU handle when shader-visible

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FenceManager

• DX12 fence management and CPU/GPU synchronization.

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ResourceManager

GPU resource + view lifetime on DX12. Creation, uploads, and deferred release.

Purpose

• Create GPU buffers/textures (static or per-frame)
• Create GPU views (CBV/SRV/UAV/RTV/DSV) + mesh views (VBV/IBV)
• Upload CPU data to GPU via per-frame upload buffers
• Defer resource/view destruction until GPU is done

Properties

• Static resources: Rarely changing resource
• Frame resources: Constantly changing. Duplicated for all frames in flight
• Views mirror resource lifetime (StaticView / FrameView)
• Per-frame UploadBuffer (UPLOAD heap, mapped CPU)
• One internal fence (Fence_ResourceManager) for upload/release sync

Upload

• requestUpload() queues external data pointer
• requestUploadOwned() returns a writable span stored in the request
• flushUploadRequests() uploads all queued requests then resets upload offset

Descriptor heaps

• Owns 4 DescriptorHeapAllocator:
• CBV/SRV/UAV, Sampler, RTV, DSV

Destruction

• requestDestroy() removes from active maps and pushes into _deferredReleases
• flushDeferredReleases() stamps pending entries with a fence value and releases when complete

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PipelineStateManager

Purpose

• Create Root Signatures from a small description
• Create and cache PSOs (Graphics / Compute)
• Bind PSOs with redundant-bind avoidance

Properties

• Stores PSOs and Shaders
• Root signature params:
• Descriptor table (DescriptorTableDesc)
• Root constants (RootConstantsDesc)

exemple : creation of a 3D pipeline state

{
        auto vs = _psoManager->compileShaderFromFile(
            toS("shader_3D_VS"), shader_dir + "/VertexShader.hlsl", "main", "vs_5_1");

        auto ps = _psoManager->compileShaderFromFile(
            toS("shader_3D_PS"), shader_dir + "/PixelShader.hlsl", "main", "ps_5_1");

        RootSignatureDescription rsDesc_VS{
            {
                DescriptorTableDesc{D3D12_DESCRIPTOR_RANGE_TYPE_SRV, 1, 0, 0,
                                    D3D12_SHADER_VISIBILITY_ALL},            // Camera
                DescriptorTableDesc{D3D12_DESCRIPTOR_RANGE_TYPE_SRV, 1, 1, 0,
                                    D3D12_SHADER_VISIBILITY_VERTEX},         // Mesh InstanceData
                RootConstantsDesc{2, 0, 0, D3D12_SHADER_VISIBILITY_ALL}      // indices : Camera, Mesh
            },
            D3D12_ROOT_SIGNATURE_FLAG_ALLOW_INPUT_ASSEMBLER_INPUT_LAYOUT};

        D3D12_INPUT_ELEMENT_DESC layout[] = {
            {"POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0,
             D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0},
            {"NORMAL", 0, DXGI_FORMAT_R32G32B32_FLOAT, 1, 0,
             D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0},
            {"TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT, 2, 0,
             D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0},
        };

        _psoManager->createGraphicsPipelineState(
            "geometry_pass", rsDesc_VS,
            [&](D3D12_GRAPHICS_PIPELINE_STATE_DESC& desc)
            {
                desc.InputLayout = {layout, _countof(layout)};
                desc.VS = {vs->_blob->GetBufferPointer(), vs->_blob->GetBufferSize()};
                desc.PS = {ps->_blob->GetBufferPointer(), ps->_blob->GetBufferSize()};
                desc.DSVFormat = DXGI_FORMAT_D32_FLOAT;
                desc.DepthStencilState.DepthEnable = 1;
                desc.DepthStencilState.DepthFunc = D3D12_COMPARISON_FUNC_LESS;
                desc.DepthStencilState.DepthWriteMask = D3D12_DEPTH_WRITE_MASK_ALL;
            });
    }

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SceneRenderer

Decouples rendering from the Scene.

Purpose

• Bind a Scene to the renderer side
• Define render passes for the current scene
• Trigger GPU instance uploads for dirty ECS data

Properties

• Holds a Scene* (no ownership)
• Uses Context to access renderer, assets, and instance manager
• Passes are registered into the RenderGraph

Rules

• Scene logic stays in ECS systems, not here
• Only consumes ECS state to render (camera selection, mesh instances)
• Uploads go through GPUInstanceManager (per frame index)

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RenderGraph

Purpose

• Organize render passes
• Record and execute per frame-in-flight

Properties

• Pass = list of record steps
• One command list per queue per frame