dotSCAD/docs/lib-turtle2d.md

turtle2d

An OpenSCAD implementation of Turtle Graphics. It moves on the xy plane. You can get the cooridinate [x, y] or angle of its current position.

Parameters

• cmd : A string command. Different commands use different numbers of arguments.
  • "create" : Creates a turtle data. The command needs three arguments x, y and angle. For example, use turtle2d("create", 5, 10, 30) to create a turtle located at [0, 0] with an angle 30 degrees.
  • "x" : Sets or gets the x coordinate of a turtle. If you provide a turtle data and the x coordinate, such as turtle2d("x", turtle, 20), it will sets the x coordinate. Giving a turtle data only will return the x coordinate.
  • "y" : Sets or gets the y coordinate of a turtle. If you provide a turtle data and the y coordinate, such as turtle2d("y", turtle, 20), it will sets the y coordinate. Giving a turtle data only will return the y coordinate.
  • "angle" : Sets or gets the angle of a turtle. If you provide a turtle data and the angle, such as turtle2d("angle", turtle, 45), it will sets the angle. Giving a turtle data only will return the angle.
  • "pt" : Sets or Gets [x, y] of a turtle. If you provide a turtle data and the coordinates, such as turtle2d("pt", turtle, [10, 20]), it will sets the coordinates. Giving a turtle data only will return the coordinates.
  • "forward" : Forwards a turtle. The command needs two arguments. The first one is a turtle data, and the second one is the length. For example, turtle2d("forward", turtle, 100).
  • "turn" : Turns a turtle. The command needs two arguments. The first one is a turtle data, and the second one is the angle. For example, turtle2d("turn", turtle, 180).

Examples

include <line2d.scad>;
include <turtle2d.scad>;

module turtle_spiral(t_before, times, side_leng, angle, width) {
    $fn = 24;
    if(times != 0) {
        t_after_tr = turtle2d("turn", t_before, angle);
        t_after_fd = turtle2d("forward", t_after_tr, side_leng);

        line2d(
            turtle2d("pt", t_before),
            turtle2d("pt", t_after_fd),
            width,
            p1Style = "CAP_ROUND", 
            p2Style =  "CAP_ROUND"
        );

        turtle_spiral(t_after_fd, times - 1, side_leng, angle, width);
    }

}

side_leng = 10;
angle = 144;
width = 1;
times = 5;

turtle_spiral(turtle2d("create", 0, 0, 0), times, side_leng, angle, width);

include <line2d.scad>;
include <turtle2d.scad>;

module turtle_spiral(t_before, side_leng, d_step, min_leng, angle, width) {
    $fn = 24;
    if(side_leng > min_leng) {
        t_after = turtle2d("forward", turtle2d("turn", t_before, angle), side_leng);

        line2d(
            turtle2d("pt", t_before),
            turtle2d("pt", t_after),
            width,
            p1Style = "CAP_ROUND", 
            p2Style =  "CAP_ROUND"
        );
        
        
        turtle_spiral(t_after, side_leng - d_step, d_step, min_leng, angle, width);
    }

}

side_leng = 50;
d_step = 1;
min_leng = 1;
angle = 90;
width = 1;

turtle_spiral(
    turtle2d("create", 0, 0, 0), 
    side_leng, 
    d_step, 
    min_leng, 
    angle, 
    width
);