将OpenGL模板功能移植到DirectX 11

时间:2013-10-11 14:10:50

标签: c++ directx directx-11 stencil-buffer

我有一些用OpenGL编写的渲染代码。我使用模板缓冲区来实现剪切:


    //Let's assume this is done in render loop.

    if(!already_created())
    {
      create_stencil_attachment_and_bind_to_FB_as_depth_stencil_attachment();
    }

    glEnable(GL_STENCIL_TEST);
    glColorMask(0,0,0,0);
    glDepthMask(0);
    glClearStencil(0);
    glClear(GL_STENCIL_BUFFER_BIT);
    glStencilFunc(GL_ALWAYS,1,1);
    glStencilOp(GL_REPLACE,GL_REPLACE,GL_REPLACE);

    render_to_stencil();

    glColorMask(1,1,1,1);
    glDepthMask(1);
    glStencilFunc(GL_EQUAL,1,1);
    glStencilOp(GL_KEEP,GL_KEEP,GL_KEEP);

    render_with_clipping();

    glDisable(GL_STENCIL_TEST);

现在,问题是,我需要将此代码移植到DX11。我在MSDN上看到了一些示例和一些很好的教程。我最终得到了这个逻辑:

1. Create ID3D11Texture2D with format = DXGI_FORMAT_D32_FLOAT_S8X24_UINT.
2. Create ID3D11DepthStencilState for rendering to stencil: //Let's call it DS_RENDER
   - For both front and back faces:
     - op = D3D11_STENCIL_OP_REPLACE for all 3 cases
     - func = D3D11_COMPARISON_ALWAYS
   - DepthEnable = FALSE
   - StencilEnable = TRUE
   - StencilReadMask = 0xFF
   - StencilWriteMask = 0xFF
3. Create ID3D11DepthStencilView for state and texture created before. //Let's call it DSV
4. Create ID3D11DepthStencilState for using stencil as 'input': //Let's call it DS_CLIP
   - For both front and back faces:
     - op = D3D11_STENCIL_OP_KEEP for all 3 cases
     - func = D3D11_COMPARISON_EQUAL
   - DepthEnable = FALSE
   - StencilEnable = TRUE
   - StencilReadMask = 0xFF
   - StencilWriteMask = 0xFF

现在,我不确定如何将模板设置为目标或输入。

MSDN说:

`pDevice->OMSetDepthStencilState(pDSState, 1);`

`pd3dDeviceContext->OMSetRenderTargets(1, &pRTV, pDSV);`

如果我正确理解这些调用,首先设置模板状态,而第二个将pDSV绑定为渲染目标的附加“附件”。这是对的吗?

如果是这样,这会像我期望的那样起作用吗?



    pDevice->OMSetDepthStencilState(DS_RENDER, 1);
    pd3dDeviceContext->OMSetRenderTargets(1, &pRTV, DSV);

    render_geometry_to_stencil_buffer();

    pDevice->OMSetDepthStencilState(DS_CLIP, 1);

    render_geometry_with_clipping();

    pd3dDeviceContext->OMSetRenderTargets(1, &pRTV, NULL); //Does this disable stencil testing?

提前感谢您的每一个帮助或有用的提示。

1 个答案:

答案 0 :(得分:1)

如果您只想渲染模具,请使用(设置您的写入状态):

pd3dDeviceContext->OMSetRenderTargets(0, NULL, DSV);

您无需渲染到颜色缓冲区,因此无需绑定它。

然后,要渲染到目标并启用模板测试,请使用:

pd3dDeviceContext->OMSetRenderTargets(1, &pRTV, DSV);

当你使用模板作为输入时,一个非常简单的事情也是设置StencilWriteMask = 0; 因此它永远不会写入它(这是你想要渲染剪裁的几何体)。

如果您使用:

pd3dDeviceContext->OMSetRenderTargets(1, &pRTV, NULL); 

您确实会禁用任何形式的深度/模板测试(不再有深度限制,因此DepthStencilState根本不起作用)。

另外,我会使用DXGI_FORMAT_D24_UNORM_S8_UINT作为深度格式(个人偏好),它将完全适合您的用例并消耗更少的内存。

希望有所帮助。