You can also add overlays on the map. These include Arrows and Spell overlays.
Arrows can now be drawn as overlays on the map. They support a start point, an end point and a color. Arrows are initiated with a *a. The formula is *a[<color>]<start point><end point>. The most common use case for arrows is to show movement for a token.
Example
https://otfbm.io/*aRa1g4/g4r/
To draw a spell overlay, use the * character then the following shape codes: c circle, l line, s square, t cone. See below for parameters.
https://otfbm.io/*c20rd5
*c circle 20 diameter r colour d5 center co-ordinate
Alternatively use *ct to anchor the circle from the top left.
https://otfbm.io/*t50ba5e5
*t cone 50 length b colour a5 start co-ordinate e5 direction co-ordinate
https://otfbm.io/*l30,5ga1b2
*l line 30 length ,5 width g colour a1 start co-ordinate b2 direction co-ordinate
https://otfbm.io/*s30ca1b2
*s square 30 size c colour a1 start co-ordinate b2 direction co-ordinate
Alternatively use *st to anchor the square at the top left. (Or don't specify the direction co-ordinate.)
https://otfbm.io/*a10pD3E5
*a arrow 10 size p colour d3 start co-ordinate e5 direction co-ordinate
In some cases you may have a need to put an overlay under tokens. Use u after the * to signify placing the item under the token layer. (an example would be the Grease spell.)
Example
A red 20 ft radius circle overlay example.
https://otfbm.io/*c20rd5/d5-Bard
A red 20 ft radius circle overlay example with u designation.
https://otfbm.io/*uc20rd5/d5-Bard