# ReflectionMatrix

gives the matrix that represents reflection of points in a mirror normal to the vector v.

# Details • The reflection is in a mirror that goes through the origin.
• ReflectionMatrix works in any number of dimensions. In 2D it reflects in a line; in 3D it reflects in a plane.

# Examples

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## Basic Examples(2)

Reflect along the axis, or equivalently reflect in the axis:

Reflect along the vector or equivalently in the plane given by :

## Scope(4)

Reflect along the vector or equivalently in the plane given by :

Points in the reflection plane remain fixed:

Points outside the reflection plane get reflected in the plane:

Reflection matrix for symbolic unit vector {u,v}:

Vectors normal to {u,v} remain unchanged:

Transformation applied to a 2D shape:

Transformation applied to a 3D shape:

## Applications(1)

Flipping a surface:

## Properties & Relations(3)

The determinant of a reflection matrix is :

The inverse of a reflection matrix is the matrix itself:

Reflection can be thought of as a special case of scaling:

## Possible Issues(1)

Reflection changes the orientation of polygons:

## Neat Examples(1)

Reflections of a cuboid in vertical planes: