Turtle

java.lang.Object
- turtle.Turtle

```
public class Turtle
extends java.lang.Object
```
Class that represents a turtle object. The turtle lives in the playground window where it draws traces when it moves. Serveral turtles can live in harmony with each other. When the turtle moves, they are overlayed, e.g. the current moving turtles is shown "on top" of other others. The size of the turtle sprites is dynamically adapted to the current device resolution,

Each turtle has an individual speed in the range 0..10 or MAXSPEED (=-1). For speeds 1..10 the turtle movement (forward, back, left, right) is animated. The trace qualitiy may suffer a little bit when speed is small because of pixel rounding errors, so for best quality use MAXSPEED.

All methods are thread-safe.

Constructor Summary

Constructors
Constructor and Description
`Turtle()` Creates a white turtle using the following defaults: - Turtle color white - Position (0, 0), center of playground - Pen color white - Heading north
`Turtle(double x, double y)` Creates a white turtle at given position using the following other defaults: - Pen color white - Heading north
`Turtle(double x, double y, int color)` Creates a turtle with given color at given position using the following other defaults: - Pen color white - Heading north
`Turtle(int color)` Creates a turtle with given color using the following other defaults: - Position (0, 0), center of playground - Pen color white - Heading north

Method Summary

Methods
Modifier and Type	Method and Description
`Turtle`	`back(double s)` Moves the turtle back.
`static void`	`beep()` Emits a beep (1000 Hz sine wave of 100 ms duration).
`Turtle`	`bk(double s)` Short for back().
`static void`	`clean()` Erases the playground by filling it with the current playground color.
`static void`	`clean(int color)` Erases the playground by filling it with the given color.
`static void`	`clear()` Clears the playground by filling it with the current playground color.
`static void`	`clear(int color)` Clears the playground by filling it with the given color.
`Turtle`	`clone()` Creates a clone of the current turtle by performing a deep copy of all its properties.
`double`	`distance(double x, double y)` Returns the distance from the current position to the given position.
`Turtle`	`dot()` Draws a single point (dot) at the current turtle position using the current pen color.
`Turtle`	`fd(double s)` Short for forward().
`Turtle`	`fill()` Same as fill(x, y), but uses the current turtle position.
`Turtle`	`fill(double x, double y)` Fills a bounded region of the playground with the current pen color (flood fill).
`Turtle`	`fillOff()` Stops the filling started by calling fillToPoint(), fillToHorizontal() or fillToVertical().
`Turtle`	`fillToHorizontal(double y)` Draws a imaginary horizonatal line at given y coordinate.
`Turtle`	`fillToPoint(double x, double y)` Attachs a imaginary rubber band between the turtle and the given anchor point.
`Turtle`	`fillToVertical(double x)` Draws a imaginary vertical line at given x coordinate.
`Turtle`	`forward(double s)` Moves the turtle forward.
`turtle.Actor`	`getActor()` Returns the underlying turtle actor.
`int`	`getColor()` Returns the current turtle color.
`double`	`getHeading()` Returns the current heading (moving direction).
`int`	`getPenColor()` Returns the current pen color.
`int`	`getPenWidth()` Returns the current pen width.
`static int`	`getPopulationSize()` Get the total number of turtles (the global turtle is not counted).
`int`	`getSpeed()` Returns the current speed (0..10, -1 for MAXSPEED).
`double`	`getX()` Returns the current x coordinate.
`double`	`getY()` Returns the current y coordinate.
`Turtle`	`hideTurtle()` Hides the turtle.
`Turtle`	`home()` Puts the turtle at home (center of playground, coordinates (0, 0).
`Turtle`	`ht()` Short for hideTurtle().
`boolean`	`isBackValid(double s)` Checks if the backward movement using the given step moves the turtle to a position outside the visible playground.
`boolean`	`isForwardValid(double s)` Checks if the forward movement using the given step moves the turtle to a position outside the visible playground.
`boolean`	`isHidden()` Reports the current visibility of the turtle.
`boolean`	`isInPlayground()` Checks, if the turtle is inside or outside the playground.
`boolean`	`isOnBorder()` Returns true, if the turtle is on any of the 4 border lines.
`boolean`	`isOnBorder(int borderId)` Returns true, if the turtle is on the selected border line.
`boolean`	`isPenDown()` Reports the current pen state of the turtle.
`Turtle`	`label(java.lang.String text)` Same as label(text, textColor, textSize) with textColor = Color.WHITE and textSize = 15.
`Turtle`	`label(java.lang.String text, int textColor, int textSize)` Paint the given text with given text color and given text height at the current turtle position
`Turtle`	`left(double angle)` Turns the turtle to the left (counter clockwise).
`Turtle`	`lt(double angle)` Short for left().
`Turtle`	`moveTo(double x, double y)` Moves the turtle to the given position.
`Turtle`	`pd()` Short for penDown().
`Turtle`	`penDown()` Lowers the turtle's pen, so it draws traces when it moves.
`Turtle`	`penUp()` Lifts the turtle's pen, so is does not draw traces when it moves.
`Turtle`	`pu()` Short for penUp().
`Turtle`	`right(double angle)` Turns the turtle to the right (clockwise).
`Turtle`	`rt(double angle)` Short for right().
`Turtle`	`setColor(int color)` Sets the current turtle color.
`Turtle`	`setHeading(double heading)` Sets the current heading (moving direction).
`Turtle`	`setPenColor(int color)` Sets the current pen color.
`Turtle`	`setPenWidth(int width)` Sets the current pen width.
`Turtle`	`setPos(double x, double y)` Puts the turtle to the given position.
`Turtle`	`setSize(int size)` Sets the current turtle size.
`Turtle`	`setSpeed(int speed)` Sets the turtle's speed.
`Turtle`	`setX(double x)` Puts the turtle to the given x coordinate.
`Turtle`	`setY(double y)` Puts the turtle to the given y coordinate.
`Turtle`	`showTurtle()` Shows the turtle if it was hidden before.
`static void`	`sleep(int time)` Delays the execution for the given time.
`Turtle`	`st()` Short for showTurtle().
`double`	`towards(double x, double y)` Returns the direction (heading) from the current position to the given position.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - Turtle
```
public Turtle()
```
    Creates a white turtle using the following defaults:
    - Turtle color white
    - Position (0, 0), center of playground
    - Pen color white
    - Heading north
  - Turtle
```
public Turtle(int color)
```
    Creates a turtle with given color using the following other defaults:
    - Position (0, 0), center of playground
    - Pen color white
    - Heading north
    
    Parameters:
    color - the initial color of the turtle (may be Color.TRANSPARENT to make the turtle invisible from the beginning)
  - Turtle
```
public Turtle(double x,
      double y)
```
    Creates a white turtle at given position using the following other defaults:
    - Pen color white
    - Heading north
    
    Parameters:
    x - the x coordinate of the creation position
    y - the y coordinate of the creation position
  - Turtle
```
public Turtle(double x,
      double y,
      int color)
```
    Creates a turtle with given color at given position using the following other defaults:
    - Pen color white
    - Heading north
    
    Parameters:
    x - the x coordinate of the creation position
    y - the y coordinate of the creation position
    color - the initial color of the turtle (may be Color.TRANSPARENT to make the turtle invisible from the beginning)
- Method Detail
  - setSpeed
```
public Turtle setSpeed(int speed)
```
    Sets the turtle's speed.
    0: stopped 1..10: speed values for the moving animation MAXSPEED (= -1) : no animation, maximal speed
    
    Parameters:
    speed - the speed of the turtle (0..10, MAXSPEED)
    
    Returns:
    the turtle reference to allow chaining
  - getSpeed
```
public int getSpeed()
```
    Returns the current speed (0..10, -1 for MAXSPEED).
    
    Returns:
    the current speed
  - forward
```
public Turtle forward(double s)
```
    Moves the turtle forward. s in turtle coordinates (coordinate system x = -200..200 to right, y = -200..200 upward).
    
    Parameters:
    s - the step to move forward, if s < 0 moves back
    
    Returns:
    the turtle reference to allow chaining
  - fd
```
public Turtle fd(double s)
```
    Short for forward().
  - back
```
public Turtle back(double s)
```
    Moves the turtle back. s in turtle coordinates (coordinate system x = -200..200 to right, y = -200..200 upward).
    
    Parameters:
    s - the step to move back, if s < 0 moves forward
    
    Returns:
    the turtle reference to allow chaining
  - bk
```
public Turtle bk(double s)
```
    Short for back().
  - right
```
public Turtle right(double angle)
```
    Turns the turtle to the right (clockwise).
    
    Parameters:
    angle - the turning angle (in degrees), if angle < 0 turns left
    
    Returns:
    the turtle reference to allow chaining
  - rt
```
public Turtle rt(double angle)
```
    Short for right().
  - left
```
public Turtle left(double angle)
```
    Turns the turtle to the left (counter clockwise).
    
    Parameters:
    angle - the turning angle (in degrees), if angle < 0 turns right
    
    Returns:
    the turtle reference to allow chaining
  - lt
```
public Turtle lt(double angle)
```
    Short for left().
  - beep
```
public static void beep()
```
    Emits a beep (1000 Hz sine wave of 100 ms duration). (This is a static method because it affects all turtles.)
  - getPopulationSize
```
public static int getPopulationSize()
```
    Get the total number of turtles (the global turtle is not counted). (This is a static method because it affects all turtles.)
    
    Returns:
    the size of the Turtle population
  - clean
```
public static void clean()
```
    Erases the playground by filling it with the current playground color. The turtles remain visible at their current position. (This is a static method because it affects all turtles.)
  - clean
```
public static void clean(int color)
```
    Erases the playground by filling it with the given color. The turtles remain visible at their current position. (This is a static method because it affects all turtles.)
  - clear
```
public static void clear()
```
    Clears the playground by filling it with the current playground color. All turtle images and traces are erased, but the turtles remain (hidden) at their current positions. Keep in mind that hiding the turtles sets their speed to MAXSPEED. (This is a static method because it affects all turtles.)
  - clear
```
public static void clear(int color)
```
    Clears the playground by filling it with the given color. All turtle images and traces are erased, but the turtles remain (hidden) at their current positions. Keep in mind that hiding the turtles sets their speed to MAXSPEED. (This is a static method because it affects all turtles.)
  - hideTurtle
```
public Turtle hideTurtle()
```
    Hides the turtle. The traces are still drawn, if pen is down. The turlte's speed is set to MAXSPEED in order to let it draw as quick as possible. Showing the turtle with showTurtle() does not affect the current speed.
    
    Returns:
    the turtle reference to allow chaining
  - ht
```
public Turtle ht()
```
    Short for hideTurtle().
  - isHidden
```
public boolean isHidden()
```
    Reports the current visibility of the turtle.
    
    Returns:
    true, if the turtle is currently hidden; otherwise false
  - showTurtle
```
public Turtle showTurtle()
```
    Shows the turtle if it was hidden before. The turtle is put on top of all other turtles. The current speed is not modified.
    
    Returns:
    the turtle reference to allow chaining
  - st
```
public Turtle st()
```
    Short for showTurtle().
  - getColor
```
public int getColor()
```
    Returns the current turtle color.
    
    Returns:
    the turtle color
  - setColor
```
public Turtle setColor(int color)
```
    Sets the current turtle color. The turtle is put on top of other turtles.
    
    Returns:
    the turtle reference to allow chaining
  - setSize
```
public Turtle setSize(int size)
```
    Sets the current turtle size. The turtle is put on top of other turtles.
    
    Parameters:
    size - one of the constants Playground.SMALLSIZE, Playground.MEDIUMSIZE, Playground.BIGSIZE
    
    Returns:
    the turtle reference to allow chaining
  - getHeading
```
public double getHeading()
```
    Returns the current heading (moving direction).
    
    Returns:
    the heading in degrees, 0 to north, clockwise
  - setHeading
```
public Turtle setHeading(double heading)
```
    Sets the current heading (moving direction). If speed is not MAXSPEED, the turtle rotation is animated, it turns to left or right for the smaller angle.
    
    Parameters:
    heading - in degrees, 0 to north, clockwise
    
    Returns:
    the turtle reference to allow chaining
  - towards
```
public double towards(double x,
             double y)
```
    Returns the direction (heading) from the current position to the given position.
    
    Parameters:
    x - the x coordinate of the target position
    y - the y coordinate of the target position
    
    Returns:
    the heading in degrees, 0 to north, clockwise
  - home
```
public Turtle home()
```
    Puts the turtle at home (center of playground, coordinates (0, 0). The movement is not animated and no trace is drawn.
    
    Returns:
    the turtle reference to allow chaining
  - isPenDown
```
public boolean isPenDown()
```
    Reports the current pen state of the turtle.
    
    Returns:
    true, if the pen is down, so traces are drawn; otherwise no traces are drawn
  - penDown
```
public Turtle penDown()
```
    Lowers the turtle's pen, so it draws traces when it moves.
    
    Returns:
    the turtle reference to allow chaining
  - pd
```
public Turtle pd()
```
    Short for penDown().
  - penUp
```
public Turtle penUp()
```
    Lifts the turtle's pen, so is does not draw traces when it moves.
    
    Returns:
    the turtle reference to allow chaining
  - pu
```
public Turtle pu()
```
    Short for penUp().
  - getPenWidth
```
public int getPenWidth()
```
    Returns the current pen width.
    
    Returns:
    the pen width in pixels (not adjusted to current screen resolution)
  - setPenWidth
```
public Turtle setPenWidth(int width)
```
    Sets the current pen width.
    
    Parameters:
    width - the pen width in pixels (independent of current screen resolution)
    
    Returns:
    the turtle reference to allow chaining
  - getPenColor
```
public int getPenColor()
```
    Returns the current pen color.
    
    Returns:
    the pen color
  - setPenColor
```
public Turtle setPenColor(int color)
```
    Sets the current pen color.
    
    Returns:
    the turtle reference to allow chaining
  - label
```
public Turtle label(java.lang.String text)
```
    Same as label(text, textColor, textSize) with textColor = Color.WHITE and textSize = 15.
  - label
```
public Turtle label(java.lang.String text,
           int textColor,
           int textSize)
```
    Paint the given text with given text color and given text height at the current turtle position
    
    Parameters:
    text - the text to show
    textColor - the text color
    textSize - the text size in turtle coordinates
    
    Returns:
    the turtle reference to allow chaining
  - distance
```
public double distance(double x,
              double y)
```
    Returns the distance from the current position to the given position.
    
    Parameters:
    x - the x coordinate of the target position
    y - the y coordinate of the target position
    
    Returns:
    the distance in turtle coordinates
  - getX
```
public double getX()
```
    Returns the current x coordinate.
    
    Returns:
    the turtle's x coordinate
  - getY
```
public double getY()
```
    Returns the current y coordinate.
    
    Returns:
    the turtle's y coordinate
  - setPos
```
public Turtle setPos(double x,
            double y)
```
    Puts the turtle to the given position. The movement is not animated and no trace is drawn.
    
    Parameters:
    x - the new turtle's x coordinate
    y - the new turtle's y coordinate
    
    Returns:
    the turtle reference to allow chaining
  - moveTo
```
public Turtle moveTo(double x,
            double y)
```
    Moves the turtle to the given position. If the speed is not MAXSPEED, the movement is animated: First the turtle turns to the new heading, then it moves forward.
    
    Parameters:
    x - the new turtle's x coordinate
    y - the new turtle's y coordinate
    
    Returns:
    the turtle reference to allow chaining
  - dot
```
public Turtle dot()
```
    Draws a single point (dot) at the current turtle position using the current pen color.
    
    Returns:
    the turtle reference to allow chaining
  - setX
```
public Turtle setX(double x)
```
    Puts the turtle to the given x coordinate. The y coordinate is maintained. The movement is not animated and no trace is drawn.
    
    Parameters:
    x - the new turtle's x coordinate
    
    Returns:
    the turtle reference to allow chaining
  - setY
```
public Turtle setY(double y)
```
    Puts the turtle to the given y coordinate. The x coordinate is maintained. The movement is not animated and no trace is drawn.
    
    Parameters:
    y - the new turtle's y coordinate
    
    Returns:
    the turtle reference to allow chaining
  - sleep
```
public static void sleep(int time)
```
    Delays the execution for the given time. If you want to stop the current turtle's movements, set its speed to 0. (This is a static method because it affects all turtles.)
    
    Parameters:
    time - the time to wait (in ms)
  - fill
```
public Turtle fill(double x,
          double y)
```
    Fills a bounded region of the playground with the current pen color (flood fill). It is assumed that the region is colored with the current playground color. The current position of the turtle is not changed.
    
    Parameters:
    x - the x coordinate of a point inside the region
    y - the y coordinate of a point inside the region
    
    Returns:
    the turtle reference to allow chaining
  - fill
```
public Turtle fill()
```
    Same as fill(x, y), but uses the current turtle position. If the turtle is sitting on its trace, a neighbor pixel with the playground color is searched.
    
    Returns:
    the turtle reference to allow chaining
  - getActor
```
public turtle.Actor getActor()
```
    Returns the underlying turtle actor.
    
    Returns:
    the actor reference
  - isOnBorder
```
public boolean isOnBorder()
```
    Returns true, if the turtle is on any of the 4 border lines.
    
    Returns:
    true, if one of the border lines intersects any of the non-transparent pixels of the turtle image
  - isOnBorder
```
public boolean isOnBorder(int borderId)
```
    Returns true, if the turtle is on the selected border line.
    
    Parameters:
    borderId - 0: top border, 1: right border, 2: bottom border, 3: left border
    
    Returns:
    true, if the border line intersects any of the non-transparent pixels of the turtle image
  - isForwardValid
```
public boolean isForwardValid(double s)
```
    Checks if the forward movement using the given step moves the turtle to a position outside the visible playground. The turtle's position remains unchanged.
    
    Parameters:
    s - the step to move forward, if s < 0 moves back
    
    Returns:
    true, if the turtle remains inside the playground; otherwise false
  - isBackValid
```
public boolean isBackValid(double s)
```
    Checks if the backward movement using the given step moves the turtle to a position outside the visible playground. The turtle's position remains unchanged.
    
    Parameters:
    s - the step to move back, if s < 0 moves forward
    
    Returns:
    true, if the turtle remains inside the playground; otherwise false
  - fillToPoint
```
public Turtle fillToPoint(double x,
                 double y)
```
    Attachs a imaginary rubber band between the turtle and the given anchor point. When the turtle now moves, the area covered by the rubber band is filled with the current pen color. Filling is on until fillOff() is called.
    
    Parameters:
    x - the x coordinate of the anchor point
    y - the y coordinate of the anchor point
    
    Returns:
    the turtle reference to allow chaining
  - fillToHorizontal
```
public Turtle fillToHorizontal(double y)
```
    Draws a imaginary horizonatal line at given y coordinate. When the turtle now moves, the trapezoidal area covered by this line and the turtle position is filled with the current pen color. Filling is on until fillOff() is called.
    
    Parameters:
    y - the y coordinate of the horizontal line
    
    Returns:
    the turtle reference to allow chaining
  - fillToVertical
```
public Turtle fillToVertical(double x)
```
    Draws a imaginary vertical line at given x coordinate. When the turtle now moves, the trapezoidal area covered by this line and the turtle position is filled with the current pen color. Filling is on until fillOff() is called.
    
    Parameters:
    x - the x coordinate of the vertical line
    
    Returns:
    the turtle reference to allow chaining
  - isInPlayground
```
public boolean isInPlayground()
```
    Checks, if the turtle is inside or outside the playground.
    
    Returns:
    true, if the turtle is inside the playgroud; otherwise false
  - fillOff
```
public Turtle fillOff()
```
    Stops the filling started by calling fillToPoint(), fillToHorizontal() or fillToVertical().
    
    Returns:
    the turtle reference to allow chaining
  - clone
```
public Turtle clone()
```
    Creates a clone of the current turtle by performing a deep copy of all its properties. Can be used to "stamp" a turtle e.g. to create a fixed turtle image at the current location. The new turtle is put on top of other turtles.
    
    Overrides:
    
    clone in class java.lang.Object
    
    Returns:
    a reference to the new turtle object

Class Turtle

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Turtle

Turtle

Turtle

Turtle

Method Detail

setSpeed

getSpeed

forward

fd

back

bk

right

rt

left

lt

beep

getPopulationSize

clean

clean

clear

clear

hideTurtle

ht

isHidden

showTurtle

st

getColor

setColor

setSize

getHeading

setHeading

towards

home

isPenDown

penDown

pd

penUp

pu

getPenWidth

setPenWidth

getPenColor

setPenColor

label

label

distance

getX

getY

setPos

moveTo

dot

setX

setY

sleep

fill

fill

getActor

isOnBorder

isOnBorder

isForwardValid

isBackValid

fillToPoint

fillToHorizontal

fillToVertical

isInPlayground

fillOff

clone