Firstborn/Library/PackageCache/com.unity.shadergraph@12.1.11/Documentation~/Rotate-About-Axis-Node.md

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2023-03-28 13:24:16 -04:00
# Rotate About Axis Node
## Description
Rotates the input vector **In** around the axis **Axis** by the value of **Rotation**. The unit for rotation angle can be selected by the parameter **Unit**.
## Ports
| Name | Direction | Type | Binding | Description |
|:------------ |:-------------|:-----|:---|:---|
| In | Input | Vector 3 | None | Input value |
| Axis | Input | Vector 3 | None | Axis to rotate around |
| Rotation | Input | Float | None | Amount of rotation to apply |
| Out | Output | Vector 3 | None | Output value |
## Controls
| Name | Type | Options | Description |
|:------------ |:-------------|:-----|:---|
| Unit | Dropdown | Radians, Degrees | Switches the unit for input **Rotation** |
## Generated Code Example
The following example code represents one possible outcome of this node per **Unit** mode.
**Radians**
```
void Unity_RotateAboutAxis_Radians_float(float3 In, float3 Axis, float Rotation, out float3 Out)
{
float s = sin(Rotation);
float c = cos(Rotation);
float one_minus_c = 1.0 - c;
Axis = normalize(Axis);
float3x3 rot_mat =
{ one_minus_c * Axis.x * Axis.x + c, one_minus_c * Axis.x * Axis.y - Axis.z * s, one_minus_c * Axis.z * Axis.x + Axis.y * s,
one_minus_c * Axis.x * Axis.y + Axis.z * s, one_minus_c * Axis.y * Axis.y + c, one_minus_c * Axis.y * Axis.z - Axis.x * s,
one_minus_c * Axis.z * Axis.x - Axis.y * s, one_minus_c * Axis.y * Axis.z + Axis.x * s, one_minus_c * Axis.z * Axis.z + c
};
Out = mul(rot_mat, In);
}
```
**Degrees**
```
void Unity_RotateAboutAxis_Degrees_float(float3 In, float3 Axis, float Rotation, out float3 Out)
{
Rotation = radians(Rotation);
float s = sin(Rotation);
float c = cos(Rotation);
float one_minus_c = 1.0 - c;
Axis = normalize(Axis);
float3x3 rot_mat =
{ one_minus_c * Axis.x * Axis.x + c, one_minus_c * Axis.x * Axis.y - Axis.z * s, one_minus_c * Axis.z * Axis.x + Axis.y * s,
one_minus_c * Axis.x * Axis.y + Axis.z * s, one_minus_c * Axis.y * Axis.y + c, one_minus_c * Axis.y * Axis.z - Axis.x * s,
one_minus_c * Axis.z * Axis.x - Axis.y * s, one_minus_c * Axis.y * Axis.z + Axis.x * s, one_minus_c * Axis.z * Axis.z + c
};
Out = mul(rot_mat, In);
}
```