Granny Strings

"Granny Strings" are from IDL are supported, so !A will move the pen up, and !N will return to its original level. Over the years support for additional controls has been added, namely some support for HTML, like <br>, and LaTeX is planned.
Color control strings are added which can modify the graphics context. And beyond that, Java/Jython codes can be plugged in which allows any customization.

Code	Description
!A	shift up one half line
!B	shift down one half line (e.g. !A3!n-!B4!n is 3/4).
!C	newline
!D	subscript 0.62 of old font size.
!U	superscript of 0.62 of old font size.
!E	superscript 0.44 of old font size.
!I	subscript 0.44 of old font size.
!N	return to the original font size.
!R	restore position to last saved position
!S	save the current position.
!K	reduce the font size. (Not in IDL's set.)
!!	the exclamation point (!)
!(ext;args)	extension and arguments for the extension, examples follow.
!(color;saddleBrown)	switch to color.
!(painter;codeId;codeArg1)	Plug-in Java code for painting regions.
<br>	newline (see also !c)
<b>	bold, </b> returns.
<i>	italics, </i> returns.

A table of example control strings and their rendering follows.

Label Text	codes used	Rendering
cm!A2	!A is shift up
cm!A2!nSM!BX!n	!n is return, !B is shift down
Bulk!cFlow	!c is newline
Bulk<br>Flow	<br> is also newline
Flow !(color;blue)Positive!(color) !(color;red)Negative!(color)	colors, note no argument returns to default color
!(color;SaddleBrown)█!(color) Brown Points	Unicode block used, to show color SVG Colors
ΔM Parameter	HTML Entities Table
☎ 555-1212	HTML Entities
some <b>Bold</b> text	Bold text