Samples a texture, tests the samples against a compare value, and returns the alpha component along with status about the operation.
TemplateType GatherCmpAlpha( _In_ SamplerState S, _In_ float Location, _In_ float CompareValue, _In_ int Offset, _Out_ uint Status );
The zero-based sampler index.
The sample coordinates (u,v).
A value to compare each against each sampled value.
The offset applied to the texture coordinates before sampling.
The status of the operation. You can't access the status directly; instead, pass the status to the CheckAccessFullyMapped intrinsic function. CheckAccessFullyMapped returns TRUE if all values from the corresponding Sample, Gather, or Load operation accessed mapped tiles in a tiled resource. If any values were taken from an unmapped tile, CheckAccessFullyMapped returns FALSE.
A four-component value whose type is the same as the template type.
The texture samples can be used for bilinear interpolation.
This function is supported for the following types of shaders: