ID3D12GraphicsCommandList：:D rawInstanced 方法 (d3d12.h)

繪製非索引的實例基本類型。

語法

void DrawInstanced(
  [in] UINT VertexCountPerInstance,
  [in] UINT InstanceCount,
  [in] UINT StartVertexLocation,
  [in] UINT StartInstanceLocation
);

參數

[in] VertexCountPerInstance

類型： UINT

要繪製的頂點數目。

[in] InstanceCount

類型： UINT

要繪製的實例數目。

[in] StartVertexLocation

類型： UINT

第一個頂點的索引。

[in] StartInstanceLocation

類型： UINT

從頂點緩衝區讀取每個實例數據之前，新增至每個索引的值。

傳回值

無

備註

繪製 API 會將工作提交至轉譯管線。

實例可能會重複使用相同的幾何，在場景中繪製多個物件，藉以擴充效能。 實例的其中一個範例可能是使用不同位置和色彩繪製相同的物件。

實例繪製呼叫的頂點數據通常來自系結至管線的頂點緩衝區。 但是，您也可以從著色器提供頂點數據，該著色器具有以系統值語意 (SV_InstanceID) 識別的實例數據。

範例

D3D12HelloTriangle 範例使用 ID3D12GraphicsCommandList：:D rawInstanced，如下所示：

D3D12_VIEWPORT m_viewport;
D3D12_RECT m_scissorRect;
ComPtr<IDXGISwapChain3> m_swapChain;
ComPtr<ID3D12Device> m_device;
ComPtr<ID3D12Resource> m_renderTargets[FrameCount];
ComPtr<ID3D12CommandAllocator> m_commandAllocator;
ComPtr<ID3D12CommandQueue> m_commandQueue;
ComPtr<ID3D12RootSignature> m_rootSignature;
ComPtr<ID3D12DescriptorHeap> m_rtvHeap;
ComPtr<ID3D12PipelineState> m_pipelineState;
ComPtr<ID3D12GraphicsCommandList> m_commandList;
UINT m_rtvDescriptorSize;

void D3D12HelloTriangle::PopulateCommandList()
{
    // Command list allocators can only be reset when the associated 
    // command lists have finished execution on the GPU; apps should use 
    // fences to determine GPU execution progress.
    ThrowIfFailed(m_commandAllocator->Reset());

    // However, when ExecuteCommandList() is called on a particular command 
    // list, that command list can then be reset at any time and must be before 
    // re-recording.
    ThrowIfFailed(m_commandList->Reset(m_commandAllocator.Get(), m_pipelineState.Get()));

    // Set necessary state.
    m_commandList->SetGraphicsRootSignature(m_rootSignature.Get());
    m_commandList->RSSetViewports(1, &m_viewport);
    m_commandList->RSSetScissorRects(1, &m_scissorRect);

    // Indicate that the back buffer will be used as a render target.
    m_commandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(m_renderTargets[m_frameIndex].Get(), D3D12_RESOURCE_STATE_PRESENT, D3D12_RESOURCE_STATE_RENDER_TARGET));

    CD3DX12_CPU_DESCRIPTOR_HANDLE rtvHandle(m_rtvHeap->GetCPUDescriptorHandleForHeapStart(), m_frameIndex, m_rtvDescriptorSize);
    m_commandList->OMSetRenderTargets(1, &rtvHandle, FALSE, nullptr);

    // Record commands.
    const float clearColor[] = { 0.0f, 0.2f, 0.4f, 1.0f };
    m_commandList->ClearRenderTargetView(rtvHandle, clearColor, 0, nullptr);
    m_commandList->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
    m_commandList->IASetVertexBuffers(0, 1, &m_vertexBufferView);
    m_commandList->DrawInstanced(3, 1, 0, 0);

    // Indicate that the back buffer will now be used to present.
    m_commandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(m_renderTargets[m_frameIndex].Get(), D3D12_RESOURCE_STATE_RENDER_TARGET, D3D12_RESOURCE_STATE_PRESENT));

    ThrowIfFailed(m_commandList->Close());
}

請參閱 D3D12 參考中的範例程式代碼。

規格需求

需求	值
目標平台	Windows
標頭	d3d12.h
程式庫	D3d12.lib
Dll	D3d12.dll

另請參閱

ID3D12GraphicsCommandList