TrvActionParaRTL is the action for "Right to Left" command.
TrvActionParaRTL = class(TrvActionParaBiDi)
This action changes the default text direction in the selected paragraphs to right-to-left. If you use this action, it's recommended to set TCustomRichViewEdit.BiDiMode to rvbdLeftToRight or rvbdRightToLeft.
This action does not introduce any new properties in addition to properties of TrvAction.
This action changes BiDiMode property for styles of the selected paragraphs (RVStyle.ParaStyles.BiDiMode) to rvbdRightToLeft.
This is a checkbox-like action, its Checked property is updated depending on the state of selection (or the current paragraph style).