Editing 2D computer graphics (section)

===Non-standard orientation of the coordinate system===

[[File:Clockwise rotation SVG.svg|thumb|A rotation through angle ''θ'' with non-standard axes]]
If a standard [[Orientation (space)|right-handed]] [[Cartesian coordinate system]] is used, with the ''x'' axis to the right and the ''y'' axis up, the rotation R(''θ'') is counterclockwise. If a left-handed Cartesian coordinate system is used, with ''x'' directed to the right but ''y'' directed down, R(''θ'') is clockwise.  Such non-standard orientations are rarely used in mathematics but are common in 2D computer graphics, which often have the origin in the top left corner and the ''y''-axis down the screen or page.<ref>{{Citation|url=http://www.w3.org/TR/SVG/coords.html#InitialCoordinateSystem|title=Scalable Vector Graphics -- the initial coordinate system|website=w3.org|year=2003}}</ref>

See [[Rotation matrix#Ambiguities|below]] for other alternative conventions which may change the sense of the rotation produced by a [[rotation matrix]].