Untitled Document

For a reflection over the x-axis,
multiply the vertex matrix on the left by:

\quad \left[\matrix{1 & 0\\0 & -1}\right]

For a reflection over the y-axis,
multiply the vertex matrix on the left by:

\quad \left[\matrix{-1 & 0\\0 & 1}\right]

For a reflection over the line y = x,
multiply the vertex matrix on the left by:

\quad \left[\matrix{0 & 1\\1 & 0}\right]

For a 90° counterclockwise rotation about the origin,
multiply the vertex matrix on the left by:

\quad \left[\matrix{0 & -1\\1 & 0}\right]

For a 180° counterclockwise rotation about the origin,
multiply the vertex matrix on the left by:

\quad \left[\matrix{-1 & 0\\0 & -1}\right]

For a 270°counterclockwise rotation about the origin,
multiply the vertex matrix on the left by:

\quad \left[\matrix{0 & 1\\-1 & 0}\right]

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