Extended SLogo Commands

Drawing Operations and Turtle Commands

Command	Description
RANDOM max	returns a random non-negative integer less than max
SETHEADING degrees SETH degrees	sets the turtle's heading to degrees
SETBACKGROUND color_number SETBG color_number	sets the background color of the screen to that represented by color_number.
SETPENCOLOR color_number SETPC color_number	sets the color of the turtle's pen to that represented by color_number
SETPENSIZE thickness SETPS thickness	sets the size of the turtle's pen to thickness
SETSHAPE shape_number SETSH shape_number	sets the shape of the turtle to that represented by shape_number
SETPALETTE color_number r g b	sets the actual color corresponding to a given number. color_number must be an integer greater than or equal to 8. (Logo tries to keep the first 8 colors constant.) The next three nonnegative integers less than 256 specify the amount of red, green, and blue in the desired color
SHAPE	returns the number of the turtle's current shape. If more than one turtle is active, return that of the first active turtle. To get the value of a specific turtle, use the command ASK.
BACKGROUND BG	returns the number of the background color
PENCOLOR PC	returns the number of the turtle's pen color. If more than one turtle is active, return that of the first active turtle. To get the value of a specific turtle, use the command ASK.
PENSIZE PS	returns the size of the turtle's pen. If more than one turtle is active, return that of the first active turtle. To get the value of a specific turtle, use the command ASK.
TELL turtle(s)	sets the turtle(s) that will follow commands hereafter.
WRAP	tells the turtle to enter wrap mode: From now on, if the turtle is asked to move past the boundary of the graphics window, it will "wrap around" and reappear at the opposite edge of the window. The top edge wraps to the bottom edge, while the left edge wraps to the right edge. This is the turtle's initial mode.
WINDOW	tells the turtle to enter window mode: From now on, if the turtle is asked to move past the boundary of the graphics window, it will move off screen. The visible graphics window is considered as just part of an infinite graphics plane; the turtle can be anywhere on the plane.
FENCE	tells the turtle to enter fence mode: From now on, if the turtle is asked to move past the boundary of the graphics window, it will move as far as it can and then stop at the edge with an "out of bounds" error message.

Control Structures and Procedures

Command	Description
IFELSE varOrCommand  [ instructionlist1 ] [ instructionlist2 ]	if varOrCommand is not 0, run instructionlist1, else run instructionlist2
ASK turtle(s) [ instructionlist ]	temporarily address turtle(s), giving them the instructions in instructionlist. This does not change the list of turtles which was set by the last tell command

Boolean Operations

Command	Description
AND test1 test2	returns 1 if test1 and test2 are 1, otherwise 0
OR test1 test2	returns 1 if test1 or test2 are 1, otherwise 1
NOT test1	returns 1 if test1 is 0, otherwise 1