Within |[@...]| the |...| are parsed as a <direction> locally, based on the current direction. The value of count register || contains the information to determine the requested direction. When no <direction> is parsed then |[@]| requests a rotation to align with the current direction.
The special sequence |[@!...]| is provided to pass an angle directly to the back-end. The -pic size and shape of the <object> with || is unchanged, even though the printed form may appear rotated. This is a feature that must be implemented specially by the back-end. For example, using the back-end, |[@!45]| will show the object rotated by 45o inside a box of the size of the unrotated object.
( @@ @@@
@@ @@ @@@@=@ @ @@##1@@@ @*shape@##1@!@!@*@*@@@@@@
@@@
@@@#1@rotate#1@@ @@@@#1@@@rotate#1@@ @@#1@@@special rotate#1@@ )
: Provide example of repeated, named transformation.
2 This adjusts the sizes of ||, ||, || and || appropriately.
( @@ @@==== @>@ == == == == - - - - @ii=@ii- @ @ii @ -@ii
@@ @@@Ignoring rotation )
Some particular rotations.
( @@left@@ v(0,1)@@ @@right@@ v(0,-1)@@ )
3