Creating Turtles
Create and assign turtles.
These commands handle the number of turtles, how they are created, and how to talk to them.
ALLTURTLES
A list of all turtles.
Syntax
ALLTURTLES
Description
ALLTURTLES outputs a list of the names of every turtle that currently defined in Logo. ALLTURTLES is equivalent to the command EVERY “TURTLE.
Example
ALLTURTLES Result: [0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15]
CTURTLES
Arranges turtles in a circle.
Syntax
CTURTLES number
Description
CTURTLES activates and makes visible the number of turtles specified by its input and arranges them in a circle in the center of the Graphics window.
CTURTLES creates a new set of turtles using the SETTURTLES command.
See also LTURTLES.
Example
DRAW CTURTLES 16 FD 100
LTURTLES
Arranges turtles in a row.
Syntax
LTURTLES number
Description
LTURTLES activates and makes visible the number of turtles specified by its input and arranges them in a horizontal line along the center of the Graphics window.
LTURTLES creates a new set of turtles using the SETTURTLES command.
See also CTURTLES.
Example
DRAW LTURTLES 15 FD 100
SETTURTLES
Also: SETT
Creates a range of turtles.
Syntax
SETTURTLES number
SETT number
Description
SETTURTLES defines the total number of turtles available. Their numbers range from 0 to the input of SETTURTLES minus 1. For example, SETTURTLES 16 will create the turtles [0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15]. By default, Logo starts with 16 turtles defined and turtle 0 activated.
SETTURTLES creates turtles with the following characteristics:
| Position | Home [0 0] |
| Turtle size | 1 |
| Heading | 0 |
| Line width | 1 |
| Color | 0 (black) |
| Turtle speed | 1 |
| Visibility | FALSE |
| Pattern | 0 |
| Pen state | PENDOWN |
| Font: | Default system font, 9 points |
SETTURTLES accepts a number between 1 and 1000 as input. The actual maximum of turtles depends on the speed of the computer. The more turtles you set, the slower turtle movements become.
TURTLES reports the number of turtles that have been defined with SETTURTLES. Use the TELL, ASK, EACH, and WHO commands to access multiple turtles.
Example
SETTURTLES 4 TURTLES Result: 4
SETTURTLENAME
Also: SETTNAME
Sets the name of a turtle.
Syntax
SETTURTLENAME :turtle :name
Description
SETTURTLENAME sets the alias name of the widget whose object name is
supplied as its first input. It also sets the widget’s TOOLTIP
property. Note that the new name is an alias to the original name; you
can use both the original and the alias name to address the widget.
To get the widget alias name, see TURTLENAME.
Example
SETTNAME 0 “JOE TNAME Result: JOE
TURTLENAME
Also: TNAME
Gets the name of the first active turtle.
Syntax
TURTLENAME
Description
TURTLENAME outputs the name of the first active turtle. This is also the value of its NAME property.
To set the turtle name, see SETTURTLENAME.
Example
SETTNAME 0 “JOE TNAME Result: JOE
TURTLENAMES
Also: TNAMES
Outputs a list of all turtle names.
Syntax
TURTLENAMES
Description
TURTLENAMES outputs a list of the names of all turtles. Note that this list does not output turtle numbers, but names if a turtle has been given an alias name. Use ALLTURTLES to obtain a list of turtle numbers.
See also TURTLENAME and SETTURTLENAME.
Example
TURTLENAMES Result: [0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 JOE JACK]
TURTLES
Reports the number of turtles.
Syntax
TURTLES
Description
The TURTLES command reports the total number of available turtles. Set the number of turtles with SETTURTLES. See also TELLALL, ALLTURTLES, TELLEVEN, and TELLODD.
Example
TURTLES Result: 16