Teleporting relative to current position reveals that getX(), getY() not queued properly

[Zachary3352]

Rather than teleporting from the location where the turtle will be in the queue, the turtle teleports relative to its original position.

[battis]

So... this proves to be a more subtle problem than @Zachary3352 and I initially thought. Let me start by embedding his code that caused the error:

import org.gannacademy.cdf.turtlelogo.AnimatedTurtle;
import org.gannacademy.cdf.turtlelogo.Turtle;

public class AnimatedTurtlesBotchThis {
    public static void triangle(Turtle t) {
        t.turn(-60);
        t.fd(20);
        t.turn(120);
        t.fd(20);
        t.turn(120);
        t.fd(20);
        t.turn(180);
        t.teleport(t.getX()+50,t.getY());
    }

    public static void main(String[] args) {
        Turtle john = new AnimatedTurtle();
        john.teleport(30,30);
        triangle(john);
        triangle(john);
    }
}

The desired outcome (which appears if using a regular Turtle) is two triangles side-by-side in the top-left corner of the canvas. The result, with the AnimatedTurtle is one triangle in the top-left corner (the first call to triangle()) and one triangle in the center of the canvas, the second call to turtle().

The issue is that the coordinates that are passed to teleport are based on a call to Turtle.getX(), and, because the queue is built before the turtle starts moving, the coordinates returned are those of the turtle in its initial position. Which means that the call to t.teleport(t.getX()+50,t.getY() in the final line of triangle(), rather than being relative to the turtle location at the end of the triangle drawing, is relative to the turtle's original position.

The first call to teleport() in main() works as expected because it uses literal coordinate values.

I shall have to ponder how best to address this problem!