ID3D11DeviceContextX::HSSetTessellationParameters Method

Sets the tessellation parameters for the Hull shader. Allows the title to provide tessellation parameters that override the driver’s calculated values, such as the number of patches per threadgroup and whether to use offchip tessellation.

Syntax

public:
void HSSetTessellationParameters(
         const D3D11X_TESSELLATION_PARAMETERS *pTessellationParameters
)

Parameters

pTessellationParameters
Type: D3D11X_TESSELLATION_PARAMETERS *

[in, optional] The tessellation parameters, as a pointer to D3D11X_TESSELLATION_PARAMETERS.

Return value

None.

Remarks

Calling HSSetTessellationParameters will change the behavior of any future Draws that use tessellation. If pTessellationParameters is NULL, the driver will use its default behavior and the driver will use the tessellation parameter values that the driver calculates. If pTessellationParameters is non-NULL, it must point to a D3D11X_TESSELLATION_PARAMETERS structure that is instantiated and populated by the title.

The main fields in the optional D3D11X_TESSELLATION_PARAMETERS structure are PatchesPerThreadgroup, TfThreshold, and DsWaveThreshold. These parameters’ values are normally calculated by the driver, taking into consideration factors including control point counts and sizes, with the overall goal of maximizing patch throughput. The application can use these fields in a call to HSSetTessellationParameters, to explicitly specify the desired values, overriding the driver’s calculations.

Even when you override the driver’s calculated parameter values, the driver might need to modify the values you specify in the D3D11X_TESSELLATION_PARAMETERS structure, to internally account for internal limitations of the GPU. To discover such modifications, call ID3D11DeviceContextX::HSGetLastUsedTessellationParameters.

See Tessellation.

Requirements

Header: Declared in d3d11_x.h.

Library: Use d3d11_x.lib.