index for control.
If the turtle was not previously activated, then all turtles from zero to
index are activated.
From now until you select a different turtle, all turtle commands refers to the newly selected turtle.
Normally, all turtles share the same PENMODE, PENSIZE and PENCOLOR.
However, if you supply the optional boolean
hasownpen input as
"true, then the selected turtle, as well as all newly activated turtles, have their own PENMODE, PENSIZE, and PENCOLOR.
You also can change a previously activated turtle to use its own pen (or not) by specifying a
hasownpen input is given and SETTURTLE does not activate any new turtles, then the selected turtle's pen remains unchanged.
hasownpen input is given and SETTURTLE activates a new turtle, then the turtle's initial pen uses the initial pen that FMSLogo uses.
; 2D Example REPEAT 8 [SETTURTLE REPCOUNT-1 FORWARD 10*REPCOUNT]
; 3D Example PERSPECTIVE CLEARSCREEN ; Draw a cube from the default vantage point REPEAT 4 [REPEAT 4 [FORWARD 100 RIGHT 90] FORWARD 100 DOWNPITCH 90]
; 3D Example with moving eye PERSPECTIVE CLEARSCREEN SETTURTLE -1 ; select the "eye position" turtle SETXYZ 500 500 500 SETTURTLE 0 ; Draw a cube from a new vantage point REPEAT 4 [REPEAT 4 [FORWARD 100 RIGHT 90] FORWARD 100 DOWNPITCH 90]