text to the screen at the turtle's current position and heading.
You can print any Logo thing (numbers, lists, strings, etc.).
text is a list, then any sub-lists are delimited by square brackets, but the entire object is not delimited by brackets.
The text is truncated according to the current values of PRINTWIDTHLIMIT and PRINTDEPTHLIMIT.
The position of the text is determined by the location of the turtle. More precisely, the top-left corner of the text is placed at the turtle's position.
The angle of the text is determined by the heading (direction) of the turtle. Not all fonts are capable of printing text at different angles, so be sure to use a TrueType or OpenType font if printing at different angles is desired.
The width and height of the text's bounding box can be determined with LABELSIZE.
LABEL can be used in PERSPECTIVE mode, but the text is not printed on the same plane as the turtle. Instead, the text is placed wherever the turtle is on the screen (in two dimensions) and oriented according to the turtle's heading.
The capabilities of the text changes depending on the device (screen or printer), the turtle heading (direction), and the font. In other words, sometimes the text can be drawn at the turtle heading and sometimes it cannot. Sometimes what is on the screen is not exactly what you print.
If you want to flash a message by writing it in one color, then writing the same message in the background color, you should disable anti-aliasing in the LABELFONT by choosing a
Quality of 3 when you run SETLABELFONT.
Otherwise, you'll end up with a faint outline of the message which you wanted to completely erase.
; label the axes of a 3D Cartesian Coordinate System TO AXIS SETLABELFONT [[Courier New] -19 0 0 700 0 0 0 0 3 2 1 49] RIGHT 90 SETY 200 LABEL "+Y SETY -200 LABEL "-Y SETY 0 SETX 200 LABEL "+X SETX -200 LABEL "-X SETX 0 SETZ 200 LABEL "+Z SETZ -200 LABEL "-Z SETZ 0 LEFT 90 END PERSPECTIVE CLEARSCREEN SETTURTLE -1 ; select the eye position SETPOSXYZ [600 600 800] SETTURTLE 0 AXIS
; flash a message TO FLASH :message ; Quality=3 disables anti-aliasing SETLABELFONT [[Arial] -19 0 0 700 0 0 0 0 3 2 3 49] PENPAINT LABEL :message WAIT 180 PENERASE LABEL :message PENPAINT END TO TELLJOKE FLASH [Q: Why did the chicken cross the road?] FLASH [A: To get to the other side!] FLASH [Ha! ha! ha!] END