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1x1 Viewport Size Variant

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Applies to: yesVisual Studio noVisual Studio for Mac

Note

This article applies to Visual Studio 2017. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here

Reduces the viewport dimensions on all render targets to 1x1 pixels.

Interpretation

A smaller viewport reduces the number of pixels that you have to shade. But, a smaller viewport doesn't reduce the number of vertices that you have to process. Setting the viewport dimensions to 1x1 pixels effectively eliminates pixel-shading from your app.

If this variant shows a large performance gain, it might indicate that your app consumes too much fill rate. In addition, your resolution could be too high for the target platform or your app could spend significant time shading pixels that are later overwritten, also know as overdraw. A smaller frame buffer or reducing the amount of overdraw will improve your app's performance.

Remarks

The viewport dimensions are reset to 1x1 pixels after every call to ID3D11DeviceContext::OMSetRenderTargets or ID3D11DeviceContext::RSSetViewports.

Example

This variant can be reproduced with the following code:

D3D11_VIEWPORT viewport;
viewport.TopLeftX = 0;
viewport.TopLeftY = 0;
viewport.Width = 1;
viewport.Height = 1;
d3d_context->RSSetViewports(1, &viewport);