faceforward
Flips the surface-normal (if needed) to face in a direction opposite to i; returns the result in n.
| ret faceforward(n, i, ng) |
|---|
This function uses the following formula: -n sign(dot(i, ng)).
Parameters
| Item | Description |
|---|---|
| n |
[in] The resulting floating-point surface-normal vector. |
| i |
[in] A floating-point, incident vector that points from the view position to the shading position. |
| ng |
[in] A floating-point surface-normal vector. |
Return Value
A floating-point, surface normal vector that is facing the view direction.
Type Description
| Name | Template Type | Component Type | Size |
|---|---|---|---|
| n | vector | float | any |
| i | vector | float | same dimension(s) as input n |
| ng | vector | float | same dimensions as input n |
| ret | vector | float | same dimensions as input n |
Minimum Shader Model
This function is supported in the following shader models.
| Shader Model | Supported |
|---|---|
| Shader Model 2 (DirectX HLSL) and higher shader models | yes |
| Shader Model 1 (DirectX HLSL) | vs_1_1 and ps_1_4 |