Enum

# VkFrontFace

Interpret polygon front-facing orientation

The first step of polygon rasterization is to determine whether the triangle
is *back-facing* or *front-facing*.
This determination is made based on the sign of the (clipped or unclipped)
polygon’s area computed in framebuffer coordinates.
One way to compute this area is:

where $x\_f^i$ and $y\_f^i$ are the x and y framebuffer coordinates of the ith vertex of the n-vertex polygon (vertices are numbered starting at zero for the purposes of this computation) and i ⊕ 1 is (i + 1) mod n.

The interpretation of the sign of a is determined by the
VkPipelineRasterizationStateCreateInfo::`frontFace`

property of
the currently active pipeline.
Possible values are:

```
typedef enum VkFrontFace {
VK_FRONT_FACE_COUNTER_CLOCKWISE = 0,
VK_FRONT_FACE_CLOCKWISE = 1,
} VkFrontFace;
```

`VK_FRONT_FACE_COUNTER_CLOCKWISE`

specifies that a triangle with positive area is considered front-facing.`VK_FRONT_FACE_CLOCKWISE`

specifies that a triangle with negative area is considered front-facing.

Any triangle which is not front-facing is back-facing, including zero-area triangles.