typedef struct D3D11X_TESSELLATION_PARAMETERS {
UINT Size;
UINT Flags;
UINT PatchesPerThreadgroup;
float TfThreshold;
UINT DsWaveThreshold;
} D3D11X_TESSELLATION_PARAMETERS;
Size
Size of this structure, in bytes, such as sizeof(D3D11X_TESSELLATION_PARAMETERS).
Flags
Flags to specify offchip tessellation and to enable each of the below values found in this structure by specifying “override”. A bitwise-OR’d combination of D3D11X_TESSELLATION_FLAGS enumeration constants.
PatchesPerThreadgroup
How many patches will be processed simultaneously in a compute unit in the GPU. Currently, the driver calculates a value for this that maximizes the number of patches that can be processed simultaneously. This field is only valid when Flags contains D3D11X_TESSELLATION_OVERRIDE_PATCHES_PER_THREADGROUP.
TfThreshold
Tessellation factor threshold for switching to offchip tessellation mode in any individual threadgroup. This is the minimum average tessellation factor in a threadgroup that will cause the hull shader to dynamically switch modes from onchip to offchip. This field is only valid when Flags contains D3D11X_TESSELLATION_OFFCHIP and D3D11X_TESSELLATION_OVERRIDE_TF_THRESHOLD. Currently, the driver calculates a tessellation factor that will generate approximately 256 DS threads (4 waves).
DsWaveThreshold
Domain Shader Wave Threshold: The number of DS waves that will be run in onchip tessellation mode, per threadgroup. This is the number of DS waves that will be launched by the tessellation unit using the onchip method, before switching DS processing to offchip mode, freeing LDS memory and starting to launch DS waves to other CUs. This field is only valid when Flags contains D3D11X_TESSELLATION_OFFCHIP and D3D11X_TESSELLATION_OVERRIDE_DS_WAVE_THRESHOLD. Currently, the driver hardcodes this to 4 waves.
This structure is passed into ID3D11DeviceContextX::HSSetTessellationParameters and is returned by ID3D11DeviceContextX::HSGetLastUsedTessellationParameters.
See Tessellation.
Header: Declared in d3d11_x.h.