The Rendering Pipeline - Practical Rendering and Computation with Direct3D 11 - page 233

Semantic Semantic Description Description

SV_DepthGreater SV_DepthGreater Depth output must he greater than the interpolated depth value

Depth output must be greater than or equal to the interpolated depth

Depth output must be greater than the interpolated depth value

Depth output must be greater than or equal to the interpolated depth
value

SV_DepthGreaterEqual SV_DepthGreaterEqual ,

value

SV_Depthl_ess SV_DepthLess Depth output must be less than the interpolated depth value Depth output must be less than the interpolated depth value

Depth output must be less than or equal to the interpolated depth

Depth output must be less than or equal to the interpolated depth
value

SV_DepthLessEqual SV DepthLessEqual ,

value

Table 3.3. System value semantics for conservative depth output.

Whether conservative depth allows a fragment to be rejected by Hi-Z depends on the
inequality, the interpolated depth value produced by the rasterizer, the depth testing func-
tion specified in the depth-stencil state, and the current value in the depth buffer. For rejec-
tion to occur, all possible depth values that could satisfy the inequality must fail the depth
test when compared against the current value in the depth buffer. As a simple example,
let's suppose that a fragment is generated with an interpolated depth of 0.75, the current
value in the depth buffer for that pixel is 0.5, and D3D11_C0MPARIS0N_LESS is specified as
the current depth comparison function. If a pixel shader without depth output is used, the
Hi-Z hardware will determine that 0.75 is greater than the current depth value, and that

Figure 3.77. Conservative depth output with "SVDepthGreaterEqual."