Arbeitsblatt 1

Arbeitsblatt 1 – EAD II
Turtlegraphik
Vorbereitung
Fügen Sie die Multimediaklassen der Bibliothek von BlueJ hinzu.
Laden Sie dazu die Klassen als zip-Datei aus den eduComponents und entpacken Sie diese.
Dann starten Sie BlueJ und öffnen unter BlueJ -> Preferences den Tab “Bibliotheken” (oder
Libraries). Fügen Sie den Pfad zu den soeben entpackten Dateien der Bibliothek hinzu.
Starten Sie BlueJ neu, damit die Einstellungen wirksam werden.
Aufgabe 1
Laden Sie sich das Beispielprogramm Turtlegraphik von der Webseite, entpacken und öffnen
Sie es in BlueJ. Testen Sie es.
Fügen Sie eine Methode hinzu:
public void zeichneRechteck(int a, int b)
Wie sollte die Methode funktionieren? Was sind a und b? Testen Sie die Methode.
Aufgabe 2
Schreiben Sie eine Methode, die ein Sechseck zeichnet. Probieren Sie auch verschiedene
Farben und Strichstärken aus. Dazu gibt es folgende Methoden:
setPenColor
public void setPenColor(java.awt.Color color)
Method to set the pen color
Parameters:
color - the color for the pen ink
setPenWidth
public void setPenWidth(int width)
Method to set the pen width
Parameters:
width - the width to use in pixels
Die Änderung der Farbe erwartet einen Parameter der Klasse Color. Diese ist hier
dokumentiert:
http://www.dpunkt.de/java/Referenz/Das_Paket_java.awt/27.html
Ein einfacher Konstruktor wäre z.B. dieser:
public Color(int r, int g, int b)
Erzeugt ein neues Color-Objekt, das mit den Rot-, Grün- und Blauanteilen r, g und b
initialisiert wird. Der Alpha-Wert wird auf 255 gesetzt.
Damit könnte man eine Frabe folgendermaßen zuweisen:
t1.setPenColor(new Color(255, 0, 0));
Aufgabe 3
Schreiben Sie eine Methode, die eine Rosette zeichnet. Diese besteht aus mehreren
Sechsecken, die um 30 Grad gedreht nacheinander gezeichnet werden.
Sie können dazu die Methode zeichneSechseck() verwenden und in einer weiteren
Methode zeichneRosette() aufrufen, die so viele Sechsecke zeichnet, wie nötig sind,
um eine Rosette zu erhalten.
Überlegen Sie sich, ob Sie Parameter für die Methoden hinzufügen wollen und wenn ja,
welche.
Hinweis:
In den Turtlegraphiken werden ganzzahlige Werte angegeben, das Zeichnen erfolgt aber über
Sinus- und Cosinusfunktionen, die mit double-Werten arbeiten. Das führt dazu, dass bei einer
ausreichend großen Zahl von Wiederholungen die Turtle nicht immer an der selben x,yPosition steht. Das kann man ausgleichen, indem man sich die Koordinaten der Startposition
merkt und nach jedem Sechseck testet, ob die Turtle wieder auf der Ausgangsposition
angekommen ist. Ist das nicht der Fall, errechnet man die Differenz und bewegt die Turtle auf
die richtige Position.
Aufgabe 4
Schreiben Sie eine Methode, die das Muster aus Bild 2 zeichnet. Es handelt sich um ein
Dreieck, das in jedem Durchgang etwas größer wird (ähnlich wie eine Spirale) und zusätzlich
noch leicht gedreht ist.
Sie sollten zuerst die Befehle für die „Dreiecksspirale“ schreiben und überprüfen, ob das
Ergebnis Ihren Erwartungen entspricht. Anschließend fügen Sie die Drehung hinzu.
Tips:
Zeichnen Sie die Figuren mit einem Stift auf ein Blatt Papier und achten Sie darauf, wie Sie
den Stift bewegen und drehen.
Schreiben Sie nicht die ganze Methode auf einmal sondern testen Sie immer wieder, was der
gerade hinzugefügte Befehl verändert.
Zusatzaufgabe
Erstellen Sie weitere Graphiken unter Verwendung weiterer Methoden, die in der Klasse
SimpleTurtle zur Verfügung gestellt werden.
Class Turtle
java.lang.Object
SimpleTurtle
Turtle
public class Turtleextends SimpleTurtle
Class that represents a turtle which is similar to a Logo turtle. This class inherts from SimpleTurtle and is for
students to add methods to. Copyright Georgia Institute of Technology 2004
Author:
Barb Ericson [email protected]
Constructor Summary
Turtle(int x, int y, ModelDisplay modelDisplayer)
Constructor that takes the x and y and a model display to draw it on
Turtle(int x, int y, Picture picture)
Constructor that takes the x and y and a picture to draw on
Turtle(ModelDisplay modelDisplay)
Constructor that takes the model display
Turtle(Picture p)
Constructor that takes a picture to draw on
Method Summary
static void
main(java.lang.String[] args)
Methods inherited from class SimpleTurtle
, backward, backward, clearPath, drawInfoString, drop, forward, forward,
getBodyColor, getDistance, getHeading, getHeight, getInfoColor,
getModelDisplay, getName, getPen, getPenColor, getPenWidth, getPicture,
getShellColor, getShowInfo, getWidth, getXPos, getYPos, hide, isPenDown,
isVisible, moveTo, paintComponent, penDown, penUp, setBodyColor, setColor,
setHeading, setHeight, setInfoColor, setModelDisplay, setName, setPen,
setPenColor, setPenDown, setPenWidth, setPicture, setShellColor,
setShowInfo, setVisible, setWidth, show, toString, turn, turnLeft,
turnRight, turnToFace, turnToFace, updateDisplay
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait,
wait
Constructor Detail
Turtle
public Turtle(int x,
int y,
ModelDisplay modelDisplayer)
Constructor that takes the x and y and a model display to draw it on
Parameters:
x - the starting x position
y - the starting y position
modelDisplayer - the thing that displays the model
Turtle
public Turtle(int x,
int y,
Picture picture)
Constructor that takes the x and y and a picture to draw on
Parameters:
x - the starting x position
y - the starting y position
picture - the picture to draw on
Turtle
public Turtle(ModelDisplay modelDisplay)
Constructor that takes the model display
Parameters:
modelDisplay - the thing that displays the model
Turtle
public Turtle(Picture p)
Constructor that takes a picture to draw on
Parameters:
p - the picture to draw on
Method Detail
main
public static void main(java.lang.String[] args)
Class SimpleTurtle
java.lang.Object
SimpleTurtle
public class SimpleTurtleextends java.lang.Object
Class that represents a Logo-style turtle. The turtle starts off facing north. A turtle can have a name, has a
starting x and y position, has a heading, has a width, has a height, has a visible flag, has a body color, can have a
shell color, and has a pen. The turtle will not go beyond the model display or picture boundaries. You can
display this turtle in either a picture or in a class that implements ModelDisplay. Copyright Georgia Institute of
Technology 2004
Author:
Barb Ericson [email protected]
Constructor Summary
SimpleTurtle(int x, int y)
Constructor that takes the x and y position for the turtle
SimpleTurtle(int x, int y, ModelDisplay display)
Constructor that takes the x and y position and the model displayer
SimpleTurtle(int x, int y, Picture picture)
Constructor that takes the x and y position and the picture to draw on
SimpleTurtle(ModelDisplay display)
Constructor that takes a model display and adds a turtle in the middle of it
SimpleTurtle(Picture picture)
Constructor that takes the picture to draw on and will appear in the middle
Method Summary
void
backward()
Method to go backward by 100 pixels
void
backward(int pixels)
Method to go backward a given number of pixels
void
clearPath()
Method to clear the path (history of where the turtle has been)
void
drawInfoString(java.awt.Graphics g)
Method to draw the information string
void
drop(Picture dropPicture)
Method to draw a passed picture at the current turtle location and
rotation in a picture or model display
void
forward()
Method to move the turtle foward 100 pixels
void
forward(int pixels)
Method to move the turtle forward the given number of pixels
java.awt.Color
getBodyColor()
Method to get the body color
double
getDistance(int x, int y)
Get the distance from the passed x and y location
double
getHeading()
Method to get the current heading
int
java.awt.Color
ModelDisplay
java.lang.String
Pen
java.awt.Color
int
Picture
java.awt.Color
boolean
getHeight()
Method to return the height of this object
getInfoColor()
Method to get the information color
getModelDisplay()
Method to get the model display for this simple turtle
getName()
Method to get the name of the turtle
getPen()
Method to get the pen
getPenColor()
Method to get the pen color
getPenWidth()
Method to get the pen width
getPicture()
Method to get the picture for this simple turtle
getShellColor()
Method to get the shell color
getShowInfo()
Method to get value of show info
int
getWidth()
Method to return the width of this object
int
getXPos()
Method to get the current x position
int
getYPos()
Method to get the current y position
void
hide()
Method to hide the turtle (stop showing it) This doesn't affect the pen
status
boolean
isPenDown()
Method to check if the pen is down
boolean
isVisible()
Method to get the value of the visible flag
void
moveTo(int x, int y)
Method to move to turtle to the given x and y location
void
paintComponent(java.awt.Graphics g)
Method to paint the turtle
void
penDown()
Method to set the pen down
void
penUp()
Method to lift the pen up
void
setBodyColor(java.awt.Color color)
Method to set the body color which will also set the pen color
void
setColor(java.awt.Color color)
Method to set the color of the turtle.
void
setHeading(double heading)
Method to set the heading
void
setHeight(int theHeight)
Method to set the height of this object
void
setInfoColor(java.awt.Color color)
Method to set the information color
void
setModelDisplay(ModelDisplay theModelDisplay)
Method to set the model display for this simple turtle
void
setName(java.lang.String theName)
Method to set the name of the turtle
void
setPen(Pen thePen)
Method to set the pen
void
setPenColor(java.awt.Color color)
Method to set the pen color
void
setPenDown(boolean value)
Method to set the pen down boolean variable
void
setPenWidth(int width)
Method to set the pen width
void
setPicture(Picture pict)
Method to set the picture for this simple turtle
void
setShellColor(java.awt.Color color)
Method to set the shell color
void
setShowInfo(boolean value)
Method to show the turtle information string
void
setVisible(boolean value)
Method to set the visible flag
void
setWidth(int theWidth)
Method to set the width of this object
void
show()
Method to show the turtle (doesn't affect the pen status
java.lang.String
void
toString()
Method to return a string with information about this turtle
turn(double degrees)
Method to turn the turtle the passed degrees use negative to turn left
and pos to turn right
void
turnLeft()
Method to turn left
void
turnRight()
Method to turn right
void
turnToFace(int x, int y)
Method to turn towards the given x and y
void
turnToFace(SimpleTurtle turtle)
Method to turn to face another simple turtle
void
updateDisplay()
Method to update the display of this turtle and also check that the
turtle is in the bounds
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait,
wait
Constructor Detail
SimpleTurtle
public SimpleTurtle(int x,
int y)
Constructor that takes the x and y position for the turtle
Parameters:
x - the x pos
y - the y pos
SimpleTurtle
public SimpleTurtle(int x,
int y,
ModelDisplay display)
Constructor that takes the x and y position and the model displayer
Parameters:
x - the x pos
y - the y pos
display - the model display
SimpleTurtle
public SimpleTurtle(int x,
int y,
Picture picture)
Constructor that takes the x and y position and the picture to draw on
Parameters:
x - the x pos
y - the y pos
picture - the picture to draw on
SimpleTurtle
public SimpleTurtle(ModelDisplay display)
Constructor that takes a model display and adds a turtle in the middle of it
Parameters:
display - the model display
SimpleTurtle
public SimpleTurtle(Picture picture)
Constructor that takes the picture to draw on and will appear in the middle
Parameters:
picture - the picture to draw on
Method Detail
backward
public void backward()
Method to go backward by 100 pixels
backward
public void backward(int pixels)
Method to go backward a given number of pixels
Parameters:
pixels - the number of pixels to walk backward
clearPath
public void clearPath()
Method to clear the path (history of where the turtle has been)
drawInfoString
public void drawInfoString(java.awt.Graphics g)
Method to draw the information string
Parameters:
g - the graphics context
drop
public void drop(Picture dropPicture)
Method to draw a passed picture at the current turtle location and rotation in a picture
or model display
Parameters:
dropPicture - the picture to drop
forward
public void forward()
Method to move the turtle foward 100 pixels
forward
public void forward(int pixels)
Method to move the turtle forward the given number of pixels
Parameters:
pixels - the number of pixels to walk forward in the heading direction
getBodyColor
public java.awt.Color getBodyColor()
Method to get the body color
Returns:
the body color
getDistance
public double getDistance(int x,
int y)
Get the distance from the passed x and y location
Parameters:
x - the x location
y - the y location
getHeading
public double getHeading()
Method to get the current heading
Returns:
the heading in degrees
getHeight
public int getHeight()
Method to return the height of this object
Returns:
the height in pixels
getInfoColor
public java.awt.Color getInfoColor()
Method to get the information color
Returns:
the color of the information string
getModelDisplay
public ModelDisplay getModelDisplay()
Method to get the model display for this simple turtle
Returns:
the model display if there is one else null
getName
public java.lang.String getName()
Method to get the name of the turtle
Returns:
the name of this turtle
getPen
public Pen getPen()
Method to get the pen
Returns:
the pen
getPenColor
public java.awt.Color getPenColor()
Method to get the pen color
Returns:
the pen color
getPenWidth
public int getPenWidth()
Method to get the pen width
Returns:
the width of the pen in pixels
getPicture
public Picture getPicture()
Method to get the picture for this simple turtle
Returns:
the picture for this turtle (may be null)
getShellColor
public java.awt.Color getShellColor()
Method to get the shell color
Returns:
the shell color
getShowInfo
public boolean getShowInfo()
Method to get value of show info
Returns:
true if should show info, else false
getWidth
public int getWidth()
Method to return the width of this object
Returns:
the width in pixels
getXPos
public int getXPos()
Method to get the current x position
Returns:
the x position (in pixels)
getYPos
public int getYPos()
Method to get the current y position
Returns:
the y position (in pixels)
hide
public void hide()
Method to hide the turtle (stop showing it) This doesn't affect the pen status
isPenDown
public boolean isPenDown()
Method to check if the pen is down
Returns:
true if down else false
isVisible
public boolean isVisible()
Method to get the value of the visible flag
Returns:
true if visible else false
moveTo
public void moveTo(int x,
int y)
Method to move to turtle to the given x and y location
Parameters:
x - the x value to move to
y - the y value to move to
paintComponent
public void paintComponent(java.awt.Graphics g)
Method to paint the turtle
Parameters:
g - the graphics context to paint on
penDown
public void penDown()
Method to set the pen down
penUp
public void penUp()
Method to lift the pen up
setBodyColor
public void setBodyColor(java.awt.Color color)
Method to set the body color which will also set the pen color
Parameters:
color - the color to use
setColor
public void setColor(java.awt.Color color)
Method to set the color of the turtle. This will set the body color
Parameters:
color - the color to use
setHeading
public void setHeading(double heading)
Method to set the heading
Parameters:
heading - the new heading to use
setHeight
public void setHeight(int theHeight)
Method to set the height of this object
Parameters:
theHeight - the height in pixels
setInfoColor
public void setInfoColor(java.awt.Color color)
Method to set the information color
Parameters:
color - the new color to use
setModelDisplay
public void setModelDisplay(ModelDisplay theModelDisplay)
Method to set the model display for this simple turtle
Parameters:
theModelDisplay - the model display to use
setName
public void setName(java.lang.String theName)
Method to set the name of the turtle
Parameters:
theName - the new name to use
setPen
public void setPen(Pen thePen)
Method to set the pen
Parameters:
thePen - the new pen to use
setPenColor
public void setPenColor(java.awt.Color color)
Method to set the pen color
Parameters:
color - the color for the pen ink
setPenDown
public void setPenDown(boolean value)
Method to set the pen down boolean variable
Parameters:
value - the value to set it to
setPenWidth
public void setPenWidth(int width)
Method to set the pen width
Parameters:
width - the width to use in pixels
setPicture
public void setPicture(Picture pict)
Method to set the picture for this simple turtle
Parameters:
pict - the picture to use
setShellColor
public void setShellColor(java.awt.Color color)
Method to set the shell color
Parameters:
color - the color to use
setShowInfo
public void setShowInfo(boolean value)
Method to show the turtle information string
Parameters:
value - the value to set showInfo to
setVisible
public void setVisible(boolean value)
Method to set the visible flag
Parameters:
value - the value to set it to
setWidth
public void setWidth(int theWidth)
Method to set the width of this object
Parameters:
theWidth - in width in pixels
show
public void show()
Method to show the turtle (doesn't affect the pen status
toString
public java.lang.String toString()
Method to return a string with informaiton about this turtle
Overrides:
toString in class java.lang.Object
Returns:
a string with information about this object
turn
public void turn(double degrees)
Method to turn the turtle the passed degrees use negative to turn left and pos to turn
right
Parameters:
degrees - the amount to turn in degrees
turnLeft
public void turnLeft()
Method to turn left
turnRight
public void turnRight()
Method to turn right
turnToFace
public void turnToFace(int x,
int y)
Method to turn towards the given x and y
Parameters:
x - the x to turn towards
y - the y to turn towards
turnToFace
public void turnToFace(SimpleTurtle turtle)
Method to turn to face another simple turtle
updateDisplay
public void updateDisplay()
Method to update the display of this turtle and also check that the turtle is in the
bounds