transform is an advanced function for directly manipulating the transformation matrix. It is designed for advanced users, and not for beginners. For most cases, 'rotate', 'scale' and 'translate' are the best functions to use.
transform( m11, m12, m21, m22, dx, dy )
Applies the given matrix to the internal matrix used for scaling, rotating and translating the screen.
This differs from 'setTransform', because that will replace that current matrix, where as this is multiplied against it.
It can be undone by calling 'undoTransform', or 'clearTransforms' to remove all transformations which have been applied.