Introduction

Layout of Chapter 15This final chapter is special and focuses primarily on graphics.

There are no homework exercises, quizzes or tests with this chapter.

However, there are 2 MAJOR Lab Projects based on the information in this chapter.

The first half of the chapter focuses on skills needed for the first project. The second half focuses on skills needed for the Final Project.

Ignore Deprecated API Warning Messages

Java is constantly improving. When newer and improved classes become available, the older classes are officially labeled “deprecated”. When you use a deprecated class, you get a warning message as seen below. Warnings are not the same thing as errors. Warnings can be ignored. We are choosing to use the older technique for mouse interaction because it is simpler. The newer technique may be preferred, but it requires knowledge of AP Computer Science topics.

// Java1501.java// This program counts the number of times a mouse is clicked.// Both left-clicks and right-clicks are counted using the <mouseDown> event. // Ignore the "deprecated API" warning.

import java.applet.Applet;import java.awt.*;

public class Java1501 extends Applet{

int numClicks;

public void init() { numClicks = 0; }public void paint(Graphics g){

g.drawString("Mouse is clicked " + numClicks + " times.",20,20);}

public boolean mouseDown(Event e, int x, int y){

numClicks++;repaint();return true;

}}

// Java1502.java// This program displays the position of the mouse every time it is clicked// using the <mouseDown> method.



int xCoord, yCoord;

public void paint(Graphics g){

g.drawString("Mouse clicked at (" + xCoord + "," + yCoord + ")",20,20);}


xCoord = x;yCoord = y;repaint();return true;

}}

// Java1503.java// This program demonstrates how to determine if the mouse is inside or// outside the Applet window using the <mouseEnter> and <mouseExit> methods.import java.applet.Applet;import java.awt.*;public class Java1503 extends Applet{

boolean insideApplet;public void paint(Graphics g){

if (insideApplet)g.drawString("Mouse is inside applet",20,20);

elseg.drawString("Mouse is outside applet",20,20);

}public boolean mouseEnter(Event e, int x, int y){

insideApplet = true;repaint();return true;

}public boolean mouseExit(Event e, int x, int y){

insideApplet = false;repaint();return true;

}}

// Java1504.java// This program determines if a mouse is clicked once or twice using the// <clickCount> method. This method works for the left or right button.

boolean singleClick,doubleClick;


if (singleClick)g.drawString("Mouse was clicked once",20,20);

if (doubleClick)g.drawString("Mouse was clicked twice",20,20);

}


switch (e.clickCount){

case 1: singleClick = true; doubleClick = false;break;

case 2:doubleClick = true; singleClick = false;

}repaint();return true;

}

// Java1505.java// This program displays the position of the mouse every time it moves// using the <mouseMove> method.



int xCoord, yCoord;


g.drawString("Mouse is located at (" + xCoord + "," + yCoord + ")",20,20);}

public boolean mouseMove(Event e, int x, int y){


}}

// Java1506.java// This program demonstrates how display to a single graphics image from a .gif file// at any x,y location on the screen. The same image can be displayed multiple times.

import java.awt.*;

public class Java1506 extends java.applet.Applet{

Image picture;

public void init(){

picture = getImage(getDocumentBase(),"LSchram.gif");}


g.drawImage(picture,0,0,this);g.drawImage(picture,750,200,this);g.drawImage(picture,350,450,this);

}}

// Java1507.java// This program demonstrates that several different images can be displayed.import java.awt.*;public class Java1507 extends java.applet.Applet{

Image picture1, picture2, picture3, picture4, picture5, picture6;public void init(){

picture1 = getImage(getDocumentBase(),"Knight.gif");picture2 = getImage(getDocumentBase(),"MouseWithCheese.gif");picture3 = getImage(getDocumentBase(),"smile.gif");picture4 = getImage(getDocumentBase(),"shark.gif");picture5 = getImage(getDocumentBase(),"Spider.gif");picture6 = getImage(getDocumentBase(),"TEDDY.gif");

}public void paint(Graphics g){

g.drawImage(picture1,100,100,this);g.drawImage(picture2,400,100,this);g.drawImage(picture3,700,100,this);g.drawImage(picture4,100,400,this);g.drawImage(picture5,400,400,this);g.drawImage(picture6,700,400,this);

}}

// Java1508.java// This program demonstrates that animated gifs are inserted in the same way as// normals gifs. Animated gifs can cause a flickering side-effect on the screen.import java.awt.*;public class Java1507 extends java.applet.Applet{


picture1 = getImage(getDocumentBase(),"space.gif");picture2 = getImage(getDocumentBase(),"computer.gif");picture3 = getImage(getDocumentBase(),"gears.gif");picture4 = getImage(getDocumentBase(),"butterfly.gif");picture5 = getImage(getDocumentBase(),"pizza.gif");picture6 = getImage(getDocumentBase(),"jet.gif");



}}

// Java1509.java// This program demonstrates that .png files also work.import java.awt.*;public class Java1509 extends java.applet.Applet{


picture1 = getImage(getDocumentBase(),"Bunny.png");picture2 = getImage(getDocumentBase(),"pineapple.png");picture3 = getImage(getDocumentBase(),"Penguin.png");picture4 = getImage(getDocumentBase(),"Koala.png");picture5 = getImage(getDocumentBase(),"house.png");picture6 = getImage(getDocumentBase(),"bird.png");



}}

// Java1510.java// This program demonstrates .jpg files can be used as well.// .jpg files are typically used for photographs.

import java.awt.*;


Image picture1, picture2, picture3, picture4;

public void init(){

picture1 = getImage(getDocumentBase(),"Paris.jpg");picture2 = getImage(getDocumentBase(),"LetSleepingDogsLie.jpg");picture3 = getImage(getDocumentBase(),"AllSmiling.jpg");picture4 = getImage(getDocumentBase(),"Schrams.jpg");

}


g.drawImage(picture1,0,0,this);g.drawImage(picture2,500,0,this);g.drawImage(picture3,0,330,this);g.drawImage(picture4,316,330,this);

}}

// Java1511.java // Problem #1 -- The image file has the wrong format.// This program demonstrates that .bmp files cannot be displayed. // Nothing will show up.// To fix this, load the bitmap file in Paint and resave it as a .gif, // .png or .jpg file.

import java.awt.*;


Image picture;

public void init(){

picture = getImage(getDocumentBase(),"ShortCircuit.bmp");}


g.drawImage(picture,100,100,this);}

}

Fixing the ProblemLoad ShortCircut.bmpin Microsoft Paint.

If double-clicking the file does not work, right click the file, select “Open with” and then select “Paint”.

Click this tab.

Click “Save as”.

Now select PNG, JPEG or GIF.

Click Save.

// Java1511.java // Problem #1 -- The image file has the wrong format.// This program demonstrates that .bmp files cannot be displayed. // Nothing will show up.// To fix this, load the bitmap file in Paint and resave it as a .gif, // .png or .jpg file.

import java.awt.*;


Image picture;

public void init(){

picture = getImage(getDocumentBase(),"ShortCircuit.png");}



}

Return to JCreator.Remember to alter the nameof the file so it matches thename of the new file that youjust created. Execute again.

// Java1512.java// Problem #2 -- The image file is not in the correct location.// This program demonstrates that an image cannot be displayed if it is not in the// correct folder. When you execute the program, nothing is displayed. Move the // "DallasSkyline.png" file from the "Dallas" subfolder to the "Programs15" folder // and execute the program again. After the file is moved, the program should work.

import java.awt.*;


Image picture;

public void init(){

picture = getImage(getDocumentBase(),"DallasSkyline.png");}



}

Fixing the ProblemThe problem is that the image file is in the Dallas subfolder and not in the Programs15 folder with the rest of the files.

Open the Dallas subfolder.

Right-click this file and select “Copy”.

Return to the Programs15 folder and paste the image file.

// Java1512.java// Problem #2 -- The image file is not in the correct location.// This program demonstrates that an image cannot be displayed if it is not in the// correct folder. When you execute the program, nothing is displayed. Move the // "DallasSkyline.png" file from the "Dallas" subfolder to the "Programs15" folder // and execute the program again. After the file is moved, the program should work.

import java.awt.*;


Image picture;

public void init(){

picture = getImage(getDocumentBase(),"DallasSkyline.png");}



}

Return to JCreator.Execute the program again.This time no alterations to the program are necessary.

Images in the Viewerare Bigger than They Appear

If you double click the file castillo.JPG it might show up in a picture viewer like the one on the right.

This is NOT the actual size of the picture.

The true size of the picture is demonstrated in the next program.

// Java1513.java// Problem #3 -- The image file is too big.// This program will be used to demonstrate what to do when a picture is too big.

import java.awt.*;


Image picture;

public void init(){

picture = getImage(getDocumentBase(),"castillo.jpg");}


Expo.setFont(g,"Snap ITC",Font.PLAIN,48);Expo.drawString(g,"El Castillo de San Felipe del Morro",15,60);g.drawImage(picture,0,100,this);

}}

Load the picture in Paint and click Resize.

Select Pixels and enter 550 for vertical.

Since “Maintain aspect ratio” is selected the Horizontal value will adjust automatically after you change the vertical.

You can also change the picture size by entering a Percentage. 50 percent would make the picture have half the length and half the width.

Press OK and save the resized picture.

Do NOT close this file! We will use it again soon.


import java.awt.*;


Image picture;

public void init(){




}}

Return to JCreator.Execute the program again.No alterations are necessary.

Solution #2 – Specify Image Dimensions

Return to Paint.Hit <Control>-<Z> to“Undo” the resizing.Re-save the image.


import java.awt.*;


Image picture;

public void init(){



Expo.setFont(g,"Snap ITC",Font.PLAIN,48);Expo.drawString(g,"El Castillo de San Felipe del Morro",15,60);g.drawImage(picture,0,100,752,500,this);

}}

Return to JCreator. Add the 2 numbers shown below to the drawImage command.Re-compile and execute.The picture will display ¼ its actual size of 3008 by 2000.

Actual Size: 3008 by 20003008 / 4 = 7522000 / 4 = 500With dimensionsof 752 by 500 the image is ¼ the width and ¼ the height or 1/16 the total area.


import java.awt.*;


Image picture;

public void init(){




}}

Change the 2 numbers in the drawImage command.Re-compile and execute.The picture will display ⅛ its actual size of 3008 by 2000.

Actual Size: 3008 by 20003008 / 8 = 3762000 / 8 = 250With dimensions of 376 by 250 the image is ⅛ the width and ⅛ the height or 1/64 the total area.


import java.awt.*;


Image picture;

public void init(){




}}

Change only the 1st number in the drawImage command.Re-compile and execute.What happened to the output?

Actual Size: Display Size:3008 by 2000 1000 by 250

The display dimensions are not proportional to the original dimensions. The result is that the image gets warped.

Solution #3 – Crop the Image

Return to Paint.

Use the scroll bars to find this image:

Use the Select tool to outline what you want

Click the Copy icon.

Click the icon and create a new file.

Click Paste.

DO NOT SAVE YET!

All of this extra white space is currently part of the picture.You need to click the bottom right corner and drag it toward the picture.

Now you can save.

Save this file as castillo.JPG,return to JCreator and executethe program again.


import java.awt.*;


Image picture;

public void init(){




}}

Return to JCreator. Remove the extra numbers from the drawImage command so that it will display the image actual size.Re-compile and execute.

Graphics EditorsThere are many Graphics Editors, any of which could be used to edit these images.

Some are simplistic like Microsoft Paint and some are more advanced and complicated.

Examples were shown with Microsoft Paint because that software is readily available.

// Java1514.java// This program demonstrates 84 of the 85 colors of the Deluxe Expo class// There is no white circle drawn since white is the background color.

// NOTE: The 10 primary colors in the Deluxe Expo class are// red, green, blue, orange, cyan, magenta, yellow, gray, pink and tan.// Each of these colors actually has 5 shades.// Example: The 5 shades of red are red, darkRed, lightRed, darkerRed and lighterRed.// There are also 35 special colors like lime, teal, navy and chartreuse to name a few.

import java.awt.*;import java.applet.*;



int radius = 60;Expo.setColor(g,Expo.darkerRed); Expo.fillCircle(g, 60, 60,radius);Expo.setColor(g,Expo.darkRed); Expo.fillCircle(g,140, 60,radius);Expo.setColor(g,Expo.red); Expo.fillCircle(g,220, 60,radius);Expo.setColor(g,Expo.lightRed); Expo.fillCircle(g,300, 60,radius);Expo.setColor(g,Expo.lighterRed); Expo.fillCircle(g,380, 60,radius);Expo.setColor(g,Expo.brown); Expo.fillCircle(g,460, 60,radius);Expo.setColor(g,Expo.violet); Expo.fillCircle(g,540, 60,radius);Expo.setColor(g,Expo.darkerGreen); Expo.fillCircle(g,620, 60,radius);Expo.setColor(g,Expo.darkGreen); Expo.fillCircle(g,700, 60,radius);Expo.setColor(g,Expo.green); Expo.fillCircle(g,780, 60,radius);Expo.setColor(g,Expo.lightGreen); Expo.fillCircle(g,860, 60,radius);Expo.setColor(g,Expo.lighterGreen); Expo.fillCircle(g,940, 60,radius);

Expo.setColor(g,Expo.darkerBlue); Expo.fillCircle(g, 60,140,radius);Expo.setColor(g,Expo.darkBlue); Expo.fillCircle(g,140,140,radius);Expo.setColor(g,Expo.blue); Expo.fillCircle(g,220,140,radius);Expo.setColor(g,Expo.lightBlue); Expo.fillCircle(g,300,140,radius);Expo.setColor(g,Expo.lighterBlue); Expo.fillCircle(g,380,140,radius);Expo.setColor(g,Expo.purple); Expo.fillCircle(g,460,140,radius);Expo.setColor(g,Expo.turquoise); Expo.fillCircle(g,540,140,radius);Expo.setColor(g,Expo.darkerOrange); Expo.fillCircle(g,620,140,radius);Expo.setColor(g,Expo.darkOrange); Expo.fillCircle(g,700,140,radius);Expo.setColor(g,Expo.orange); Expo.fillCircle(g,780,140,radius);Expo.setColor(g,Expo.lightOrange); Expo.fillCircle(g,860,140,radius);Expo.setColor(g,Expo.lighterOrange); Expo.fillCircle(g,940,140,radius);

Expo.setColor(g,Expo.darkerCyan); Expo.fillCircle(g, 60,220,radius);Expo.setColor(g,Expo.darkCyan); Expo.fillCircle(g,140,220,radius);Expo.setColor(g,Expo.cyan); Expo.fillCircle(g,220,220,radius);Expo.setColor(g,Expo.lightCyan); Expo.fillCircle(g,300,220,radius);Expo.setColor(g,Expo.lighterCyan); Expo.fillCircle(g,380,220,radius);Expo.setColor(g,Expo.plum); Expo.fillCircle(g,460,220,radius);Expo.setColor(g,Expo.indigo); Expo.fillCircle(g,540,220,radius);Expo.setColor(g,Expo.darkerMagenta); Expo.fillCircle(g,620,220,radius);Expo.setColor(g,Expo.darkMagenta); Expo.fillCircle(g,700,220,radius);Expo.setColor(g,Expo.magenta); Expo.fillCircle(g,780,220,radius);Expo.setColor(g,Expo.lightMagenta); Expo.fillCircle(g,860,220,radius);Expo.setColor(g,Expo.lighterMagenta); Expo.fillCircle(g,940,220,radius);

Expo.setColor(g,Expo.darkerYellow); Expo.fillCircle(g, 60,300,radius);Expo.setColor(g,Expo.darkYellow); Expo.fillCircle(g,140,300,radius);Expo.setColor(g,Expo.yellow); Expo.fillCircle(g,220,300,radius);Expo.setColor(g,Expo.lightYellow); Expo.fillCircle(g,300,300,radius);Expo.setColor(g,Expo.lighterYellow); Expo.fillCircle(g,380,300,radius);Expo.setColor(g,Expo.aqua); Expo.fillCircle(g,460,300,radius);Expo.setColor(g,Expo.aquaMarine); Expo.fillCircle(g,540,300,radius);Expo.setColor(g,Expo.darkerPink); Expo.fillCircle(g,620,300,radius);Expo.setColor(g,Expo.darkPink); Expo.fillCircle(g,700,300,radius);Expo.setColor(g,Expo.pink); Expo.fillCircle(g,780,300,radius);Expo.setColor(g,Expo.lightPink); Expo.fillCircle(g,860,300,radius);Expo.setColor(g,Expo.lighterPink); Expo.fillCircle(g,940,300,radius);

Expo.setColor(g,Expo.goldenRod); Expo.fillCircle(g, 60,380,radius);Expo.setColor(g,Expo.gold); Expo.fillCircle(g,140,380,radius);Expo.setColor(g,Expo.silver); Expo.fillCircle(g,220,380,radius);Expo.setColor(g,Expo.bronze); Expo.fillCircle(g,300,380,radius);Expo.setColor(g,Expo.teal); Expo.fillCircle(g,380,380,radius);Expo.setColor(g,Expo.maroon); Expo.fillCircle(g,460,380,radius);Expo.setColor(g,Expo.fuschia); Expo.fillCircle(g,540,380,radius);Expo.setColor(g,Expo.lavender); Expo.fillCircle(g,620,380,radius);Expo.setColor(g,Expo.lime); Expo.fillCircle(g,700,380,radius);Expo.setColor(g,Expo.navy); Expo.fillCircle(g,780,380,radius);Expo.setColor(g,Expo.chartreuse); Expo.fillCircle(g,860,380,radius);Expo.setColor(g,Expo.fireBrick); Expo.fillCircle(g,940,380,radius);

Expo.setColor(g,Expo.moccasin); Expo.fillCircle(g, 60,460,radius);Expo.setColor(g,Expo.salmon); Expo.fillCircle(g,140,460,radius);Expo.setColor(g,Expo.olive); Expo.fillCircle(g,220,460,radius);Expo.setColor(g,Expo.khaki); Expo.fillCircle(g,300,460,radius);Expo.setColor(g,Expo.crimson); Expo.fillCircle(g,380,460,radius);Expo.setColor(g,Expo.orchid); Expo.fillCircle(g,460,460,radius);Expo.setColor(g,Expo.sienna); Expo.fillCircle(g,540,460,radius);Expo.setColor(g,Expo.melon); Expo.fillCircle(g,620,460,radius);Expo.setColor(g,Expo.tangerine); Expo.fillCircle(g,700,460,radius);Expo.setColor(g,Expo.terraCotta); Expo.fillCircle(g,780,460,radius);Expo.setColor(g,Expo.pumpkin); Expo.fillCircle(g,860,460,radius);Expo.setColor(g,Expo.mahogany); Expo.fillCircle(g,940,460,radius);

Expo.setColor(g,Expo.darkerTan); Expo.fillCircle(g, 60,540,radius);Expo.setColor(g,Expo.darkTan); Expo.fillCircle(g,140,540,radius);Expo.setColor(g,Expo.tan); Expo.fillCircle(g,220,540,radius);Expo.setColor(g,Expo.lightTan); Expo.fillCircle(g,300,540,radius);Expo.setColor(g,Expo.lighterTan); Expo.fillCircle(g,380,540,radius);Expo.setColor(g,Expo.amber); Expo.fillCircle(g,460,540,radius);Expo.setColor(g,Expo.black); Expo.fillCircle(g,540,540,radius);Expo.setColor(g,Expo.darkerGray); Expo.fillCircle(g,620,540,radius);Expo.setColor(g,Expo.darkGray); Expo.fillCircle(g,700,540,radius);Expo.setColor(g,Expo.gray); Expo.fillCircle(g,780,540,radius);Expo.setColor(g,Expo.lightGray); Expo.fillCircle(g,860,540,radius);Expo.setColor(g,Expo.lighterGray); Expo.fillCircle(g,940,540,radius);

}}

The drawRoundedRectangle MethodExpo.drawRoundedRectangle(g, x1, y1, x2, y2, pixels);Draws a rectangle with a top-left corner at coordinate (x1,y1) and a bottom-right hand corner of (x2,y2). Pixels determines how curved the corners will be.

x1, y1

x2, y2

pixels

The drawSpiral MethodExpo.drawSpiral(g, centerX, centerY, radius);

The parameters for Expo.drawSpiral are identical to Expo.drawCircle.

centerX, centerY

radius

The drawBurst MethodExpo.drawBurst(g, centerX, centerY, radius, numLines);The first 4 parameters for Expo.drawBurst are the same as Expo.drawCircle.The last parameter indicates the number of lines.

centerX, centerY

radius

The drawRandomBurst MethodExpo.drawRandomBurst(g, centerX, centerY, radius, numLines);The first 4 parameters for Expo.drawRandomBurst are the same as Expo.drawCircle.The last parameter indicates the number of random lines.

centerX, centerY

radius

// Java1515.java// This program demonstrates the drawSpiral, drawBurst and drawRandomBurst // methods of the Deluxe Expo class.// All three of these methods share the same parameters as drawCircle.// The two "Burst" methods have an additional parameter for the number of lines.// It also demonstrates the drawRoundedRectangle method of the Deluxe Expo class.// It shares the same parameters as drawRectangle, except there is an extra parameter// to control how "rounded" the corners will be.




Expo.drawRoundedRectangle(g,10,20,990,300,25);Expo.drawSpiral(g,180,160,100);Expo.drawBurst(g,500,160,100,8);Expo.drawRandomBurst(g,820,160,100,300);

Expo.drawRoundedRectangle(g,10,320,990,640,100);Expo.drawSpiral(g,180,480,150);Expo.drawBurst(g,500,480,150,40);Expo.drawRandomBurst(g,820,480,150,5000);

}}

// Java1516.java// This program demonstrates the "drawThick" methods of the Deluxe Expo class.// All "draw" methods in the Deluxe Expo class have a corresponding "drawThick"// method with the same parameters, except that the "drawThick" methods have // an extra parameter to control the "thickness".




int t = 12; // thicknessExpo.setColor(g,Expo.blue);Expo.drawThickLine(g,100,80,900,80,t);Expo.drawThickRectangle(g,50,30,950,620,t);Expo.drawThickCircle(g,500,310,200,t);Expo.drawThickOval(g,400,300,30,40,t);Expo.drawThickStar(g,400,300,100,10,t);Expo.drawThickOval(g,600,300,30,40,t);Expo.drawThickStar(g,600,300,90,6,t);Expo.drawThickArc(g,500,415,105,65,90,270,t);

Expo.drawThickRoundedRectangle(g,100,100,200,600,25,t);Expo.drawThickRoundedRectangle(g,800,100,900,500,50,t);Expo.drawThickSpiral(g,280,115,100,t);Expo.drawThickSpiral(g,700,115,100,t);Expo.setColor(g,Expo.red);Expo.drawThickBurst(g,150,350,150,20,t);Expo.drawThickRandomBurst(g,850,350,150,300,t);Expo.setColor(g,Expo.darkGreen);Expo.drawThickRegularPolygon(g,150,555,40,3,t);Expo.drawThickRegularPolygon(g,250,555,40,4,t);Expo.drawThickRegularPolygon(g,350,555,40,5,t);Expo.drawThickRegularPolygon(g,450,555,40,6,t);Expo.drawThickRegularPolygon(g,550,555,40,7,t);Expo.drawThickRegularPolygon(g,650,555,40,8,t);Expo.drawThickRegularPolygon(g,750,555,40,9,t);Expo.drawThickRegularPolygon(g,850,555,40,10,t);

}}

// Java1517.java// This program shows how to have user input in a graphics program with the// enterIntGUI and enterStringGUI methods of the Deluxe Expo class.// Methods enterDoubleGUI and enterCharGUI are also available.import java.awt.*;public class Java1517 extends java.applet.Applet{

int amount;String imageFile;Image picture;public void init(){

String imageFile = Expo.enterStringGUI("What image do you wish to display?");picture = getImage(getDocumentBase(), imageFile);amount =

Expo.enterIntGUI("How many times do you wish to display this image?");}public void paint(Graphics g){

for (int j = 1; j <=amount; j++){

int x = Expo.random(0,900);int y = Expo.random(0,550);g.drawImage(picture,x,y,this);

}}

}

Java1517.java Input

As before, you are provided with the file Expo.html which documents all of the methods in the Deluxe Expo class (both old and new).

// Java1518.java This program shows how to display multiple pages of graphics output.import java.awt.*;public class Java1518 extends java.applet.Applet{

int numClicks;Image picture1, picture2, picture3, picture4, picture5;

public void init(){

numClicks = 0;picture1 = getImage(getDocumentBase(),"LSchram.gif");picture2 = getImage(getDocumentBase(),"JSchram.jpg");picture3 = getImage(getDocumentBase(),"nederlands.gif");picture4 = getImage(getDocumentBase(),"leon&isolde.jpg");picture5 = getImage(getDocumentBase(),"JPIILogo.jpg");

// The following MediaTracker/try/catch code ensures that// all images are loaded before the program continues.MediaTracker tracker = new MediaTracker(this);tracker.addImage(picture1,1); tracker.addImage(picture2,1);tracker.addImage(picture3,1); tracker.addImage(picture4,1);tracker.addImage(picture5,1);try{

tracker.waitForAll();}catch(InterruptedException e){

System.out.println(e);}

}


switch (numClicks){

case 0 : page1(g); break;case 1 : page2(g); break;case 2 : page3(g); break;

}}


numClicks++;repaint();return true;

}

public void page1(Graphics g){

Expo.setFont(g,"Arial",Font.BOLD,100);Expo.drawString(g,"TITLE PAGE",218,100);Expo.setColor(g,Expo.yellow);Expo.drawThickPreciseSpiral(g,510,370,275,50,15);Expo.setColor(g,Expo.red);Expo.fillStar(g,510,370,175,8);Expo.setColor(g,Expo.green);Expo.drawThickStar(g,510,370,225,8,25);Expo.setColor(g,Expo.blue);Expo.drawThickStar(g,510,370,275,8,25);g.drawImage(picture1,425,285,this);Expo.setFont(g,"Times Roman",Font.PLAIN,20);Expo.drawString(g,"My name is Leon Schram.",30,300);Expo.drawString(g,"Click once to continue.",760,550);

}


Expo.setFont(g,"Algerian",Font.BOLD,100);Expo.drawString(g,"PAGE 2",200,100);Expo.setColor(g,Expo.blue);Expo.fillRectangle(g,100,250,900,500);Expo.setColor(g,Expo.chartreuse);g.drawImage(picture3,200,300,this);g.drawImage(picture4,500,280,this);Expo.setColor(g,Expo.blue);Expo.setFont(g,"Times Roman",Font.PLAIN,20);Expo.drawString(g,"I was born in the Netherlands in

1945 and married my sweet wife Isolde in 1967.",100,200);Expo.drawString(g,"Click once to continue.",750,550);

}


Expo.setFont(g,"Impact",Font.BOLD,100);Expo.drawString(g,"PAGE 3",200,100);Expo.setColor(g,Expo.darkGreen);Expo.fillRoundedRectangle(g,460,170,960,515,50);g.drawImage(picture5,150,225,this);g.drawImage(picture2,500,193,this);Expo.setFont(g,"Times Roman",Font.PLAIN,20);Expo.drawString(g,"I teach Computer Science at John

Paul II High School with my son John.",100,150);Expo.drawString(g,"Click once to continue.",750,550);

}}

End of Part 1Program Java1518.java concludes the Part 1 section which prepares you for the Personal Slide Show project.

See the GraphicsLab09.docx file for assignment details.

Beginning of Part 2The remaining programs are to help prepare you for the Final Graphics Project. This will be the biggest assignment of the year.

// Java1519.java// This program draws a small square at every mouse click position.// There are 2 problems with the program:// First, it draws a square in the upper left hand corner automatically before we have a// chance to do anything. Second, it will only draws one square at a time.



int xCoord;int yCoord;


Expo.setColor(g,Expo.red);Expo.fillRectangle(g,xCoord,yCoord,xCoord+15,yCoord+15);

}


xCoord = x; yCoord = y;repaint();return true;

}}

// Java1520.java// This program cures the problem of the initial red square by adding a "firstPaint" boolean variable.import java.applet.Applet;import java.awt.*;public class Java1520 extends Applet{

int xCoord;int yCoord;boolean firstPaint;public void init() { firstPaint = true; }public void paint(Graphics g){

if (firstPaint)firstPaint = false;

else{


}}public boolean mouseDown(Event e, int x, int y){


}}

// Java1521.java// This program adds the clever "update" method which prevents the computer from clearing the // paint window every time it is refreshed. This allows you to draw more than one square at a time.import java.applet.Applet;import java.awt.*;public class Java1521 extends Applet{

int xCoord;int yCoord;boolean firstPaint;public void init() { firstPaint = true; }public void paint(Graphics g){

if (firstPaint)firstPaint = false;

else{


}}public boolean mouseDown(Event e, int x, int y){

xCoord = x; yCoord = y;repaint();return true;

}

public void update(Graphics g) { paint(g); }}

// Java1522.java// This program changes "mouseDown" to "mouseDrag" and makes the square smaller.// This should create the effect of having a freehand pencil.



int xCoord,yCoord;

public void init(){

xCoord = 0;yCoord = 0;

}


Expo.setColor(g,Expo.red);Expo.drawPoint(g,xCoord,yCoord);

}

public boolean mouseDrag(Event e, int x, int y){


}


// Java1523.java// This program draws a straight line from the point where the mouse is clicked// to the point where the mouse is released.



int startX,startY,endX,endY;


Expo.drawLine(g,startX,startY,endX,endY);}


startX = x;startY = y;return true;

}

public boolean mouseUp(Event e, int x, int y){

endX = x;endY = y;repaint();return true;

}}

// Java1524.java// This program draws a straight line from the point where the mouse is clicked// to the point where the mouse is released. In this example the line is // constantly visible. This is sometimes called the "rubber band" effect.import java.applet.Applet;import java.awt.*;public class Java1524 extends Applet{






}



}}

// Java1525.java// This program shows that method "update" can causes a peculiar "side effect" in some cases.// Watch what happens when you try to draw a line.







startX = x; startY = y;return true;

}


endX = x; endY = y;repaint();return true;

}


// Java1526.java// This program is almost identical to Java1524.java.// The only difference is that "drawLine" has been changed to "drawRectangle".// Note how the rectangles are draw with the same "rubber band effect" as the lines.





Expo.drawRectangle(g,startX,startY,endX,endY);}



}



}}

Drawing CirclesDrawing circles is more complicated than drawing lines or rectangles.

A circles has a center and a radius.

mouseDown determines the center.

mouseUp determines a point on the rim of the circle.

To find the radius we need to find the distance between these 2 points using the distance formula which is based on the Pythagorean Theorem.

Pythagorean TheoremThis Theorem states that in a right triangle, the square of the hypotenuse (longest side) is equal to thesum of the squares of the a c2 shorter sides.

So c2 = a2 + b2 b

The actual formula for finding the hypotenuse is:

Distance FormulaThe distance between 2 points in a coordinate plane is essentially the hypotenuse of the right triangle they form.

(x2,y2)

(x1, y1)

(x2, y2)

// Java1527.java// This program will draw circles using a special "getRadius" method// which is based on the Pythagorean Formula.import java.applet.Applet;import java.awt.*;public class Java1527 extends Applet{

int centerX,centerY,rimX,rimY;public void paint(Graphics g){

int radius = getRadius(centerX,centerY,rimX,rimY);Expo.drawCircle(g,centerX,centerY,radius);

}public boolean mouseDown(Event e, int x, int y){

centerX = x; centerY = y;return true;

}public boolean mouseDrag(Event e, int x, int y){

rimX = x; rimY = y;repaint();return true;

}public int getRadius(int x1, int y1, int x2, int y2){

double radius = Math.sqrt(Math.pow(x2-x1,2) + Math.pow(y2-y1,2));return (int) radius;

}}

// Java1528.java// This uses the <Rectangle> class with the // <inside> method to determine if a certain // square has been clicked.import java.applet.Applet;import java.awt.*;public class Java1528 extends Applet{

Rectangle red, green, blue;int numColor;

public void init(){

red = new Rectangle(100,75,150,150);

green = new Rectangle(100,275,150,150);

blue = new Rectangle(100,475,150,150);

numColor = 0;}

public boolean mouseDown(Event e, int x, int y)

{if(red.inside(x,y))

numColor = 1;else if(green.inside(x,y))

numColor = 2;else if(blue.inside(x,y))

numColor = 3;else

numColor = 4;repaint();return true;

}


Expo.setColor(g,Expo.red);Expo.fillRectangle(g,100,75,250,225);Expo.setColor(g,Expo.green);Expo.fillRectangle(g,100,275,250,425);Expo.setColor(g,Expo.blue);Expo.fillRectangle(g,100,475,250,625);Expo.setFont(g,"Arial",Font.BOLD,28);switch (numColor){

case 1:Expo.setColor(g,Expo.red);g.drawString("Mouse

clicked inside red",300,150);break;

case 2:

Expo.setColor(g,Expo.green);g.drawString("Mouse

clicked inside green",300,350);break;

case 3:

Expo.setColor(g,Expo.blue);g.drawString("Mouse

clicked inside blue",300,550);break;

case 4:

Expo.setColor(g,Expo.black);g.drawString( "Mouse clicked outside

the colored squares",300,40);break;

}} }

// Java1529.java// This program proves that objects of the <Rectangle> class are abstract to the viewer and// not visible. The three square are intentionally not displayed. The program still works// like the previous program, but you must guess at the location of the squares.

import java.applet.Applet;import java.awt.*;public class Java1529 extends Applet{

Rectangle red, green, blue;int numColor;public void init(){

red = new Rectangle(100,75,150,150);

green = new Rectangle(100,275,150,150);

blue = new Rectangle(100,475,150,150);

numColor = 0;}public boolean mouseDown(Event e,

int x, int y){

if(red.inside(x,y))numColor = 1;

else if(green.inside(x,y))numColor = 2;

else if(blue.inside(x,y))numColor = 3;

elsenumColor = 4;

repaint();return true;

}


// Note: The solid colored squares are not drawn this time.

Expo.setFont(g,"Arial",Font.BOLD,28);switch (numColor){

case 1:Expo.setColor(g,Expo.red);g.drawString("Mouse

clicked inside red",300,150);break;

case 2:

Expo.setColor(g,Expo.green);g.drawString("Mouse

clicked inside green",300,350);break;

case 3:

Expo.setColor(g,Expo.blue);g.drawString("Mouse

clicked inside blue",300,550);break;

case 4:

Expo.setColor(g,Expo.black);g.drawString( "Mouse clicked outside

the colored squares",300,40);break;

}}}

Difference BetweenDrawing Rectangles and

Creating Rectangle ObjectsExpo.drawRectangle(g,x1,y1,x2,y2); Rectangle area = new Rectangle(x,y,width,height);

// Java1530.java Animation Part 1// This program simply draws a solid black circle.// This will eventually be "animated" as we go through // the next few programs. import java.awt.*; public class Java1530 extends java.applet.Applet{


Expo.fillCircle(g,50,325,25);}

}

// Java1531.java Animation Part 2// This program simply draws the solid black circle at 10 different locations.// This is not yet animation because we see all 10 circles at the same time. import java.awt.*; public class Java1531 extends java.applet.Applet{


Expo.fillCircle(g,50,325,25);Expo.fillCircle(g,150,325,25);Expo.fillCircle(g,250,325,25);Expo.fillCircle(g,350,325,25);Expo.fillCircle(g,450,325,25);Expo.fillCircle(g,550,325,25);Expo.fillCircle(g,650,325,25);Expo.fillCircle(g,750,325,25);Expo.fillCircle(g,850,325,25);Expo.fillCircle(g,950,325,25);

}}

// Java1532.java Animation Part 3// This program erases every circle before it draws the next one.// This is necessary for animation; however, the process happens // so fast you cannot see the circle move. import java.awt.*; public class Java1532 extends java.applet.Applet{


Expo.setColor(g,Expo.black);Expo.fillCircle(g,50,325,25);Expo.setColor(g,Expo.white);Expo.fillCircle(g,50,325,25);










}}

// Java1533.java Animation Part 4// This program adds a short 1 second delay after each circle is drawn// to give you a chance to see it before it is erased. import java.awt.*; public class Java1533 extends java.applet.Applet{


Expo.setColor(g,Expo.black);Expo.fillCircle(g,50,325,25);Expo.delay(1000);Expo.setColor(g,Expo.white);Expo.fillCircle(g,50,325,25);




Expo.setColor(g,Expo.black);Expo.fillCircle(g,450,325,25);Expo.delay(1000);Expo.setColor(g,Expo.white);Expo.fillCircle(g,450,325,25); Expo.setColor(g,Expo.black);Expo.fillCircle(g,550,325,25);Expo.delay(1000);Expo.setColor(g,Expo.white);Expo.fillCircle(g,550,325,25);





}}

Program NoteThe output of program Java1533.java was simulated with PowerPoint.

It will not be possible to simulate the output of the remaining programs.

You need to execute them on your own computer to truly see what they are doing.

// Java1534.java Animation Part 5// This program has the same output as the previous program.// The program is now much shorter since a for loop is used. import java.awt.*; public class Java1534 extends java.applet.Applet{


for (int x = 50; x <= 950; x+=100){

Expo.setColor(g,Expo.black);Expo.fillCircle(g,x,325,25);Expo.delay(1000);Expo.setColor(g,Expo.white);Expo.fillCircle(g,x,325,25);

}}

}

// Java1535.java Animation Part 6// This program makes the animation smoother by using a smaller delay// and a smaller increment in the for loop. import java.awt.*; public class Java1535 extends java.applet.Applet{


for (int x = 50; x <= 950; x+=10){


}}

}

// Java1536.java Animation Part 7// This program makes the animation as smooth as possible by having an // increment of just 1 pixel in the for loop. The delay is also made smaller. import java.awt.*; public class Java1536 extends java.applet.Applet{


for (int x = 50; x <= 950; x+=1){


}}

}

Animation ReviewTo achieve animation, you need to dothe following:

1) Draw something

2) Delay for a fraction of a second

3) Erase it by drawing over it in the background color.

4) Redraw it in a slightly different location and repeat.

// Java1537.java Animation Part 8// This program draws and erases 3 circles instead of one to animate a snowman across the screen.// The flickering that you will see is normal for this type of animation.// In AP Computer Science you will learn a more advanced type of animation that eliminates the flicker. import java.awt.*; public class Java1537 extends java.applet.Applet{


for (int x = 50; x <= 950; x+=1){

Expo.setColor(g,Expo.black);Expo.fillCircle(g,x,290,15);Expo.fillCircle(g,x,325,25);Expo.fillCircle(g,x,380,40);Expo.delay(10);Expo.setColor(g,Expo.white);Expo.fillCircle(g,x,290,15);Expo.fillCircle(g,x,325,25);Expo.fillCircle(g,x,380,40);

}}

}

// Java1538.java Animation Part 9// This program shows that an image from a file can also be made to move across the screen.// As with the snowman, there can be considerable flickering.

import java.awt.*;


Image picture;

public void init(){

picture = getImage(getDocumentBase(),"bunny.png");}


for (int x = -100; x <= 1100; x+=3){

g.drawImage(picture,x,200,this);Expo.delay(30);Expo.setColor(g,Expo.white);Expo.fillRectangle(g,x,200,x+100,300);

}}

}

// Java1539.java Animation Part 10// This program demonstrates the problem that occurs with a multi-colored background.import java.awt.*;public class Java1539 extends java.applet.Applet{


for (int c = 1; c <= 9; c++){

Expo.setColor(g,c);Expo.fillRectangle(g, (c-1)*111, 0, c*111, 650);

}

for (int x = 50; x <= 950; x+=3){

Expo.setColor(g,Expo.black);Expo.fillCircle(g,x,290,15);Expo.fillCircle(g,x,325,25);Expo.fillCircle(g,x,380,40);Expo.delay(30);Expo.setColor(g,Expo.red);Expo.fillCircle(g,x,290,15);Expo.fillCircle(g,x,325,25);Expo.fillCircle(g,x,380,40);

}}

}

// Java1540.java Animation Part 11// This program shows how to handle a multi-colored background.// Instead of "draw-and-erase", it is "draw-and-redraw".// The entire background is redrawn every time the object moves.// NOTE: This does have the potential for serious flickering.

import java.awt.*;



for (int x = 50; x <= 950; x+=3){

for (int c = 1; c <= 9; c++){

Expo.setColor(g,c);Expo.fillRectangle(g, (c-1)*111, 0, c*111, 650);

}Expo.setColor(g,Expo.black);Expo.fillCircle(g,x,290,15);Expo.fillCircle(g,x,325,25);Expo.fillCircle(g,x,380,40);Expo.delay(30);

}}

}

Programming KnowledgeNever Becomes Obsolete

Some people may be concerned that with technology changing so rapidly, the programming knowledge that they have acquired in this course will soon be out of date. While new programming languages pop up from time to time, the logic of programming has never changed.

The next three programs all do the exact same thing. The first is written in Java. The second in C++ and the third in Pascal. Even though you may have never seen C++ or Pascal, you may be surprised how familiar these programs will look to you now that you know Java.

// Java1541.java// This program will count backwards from 20 to 0 and displays which numbers// are even and which are odd.// Compare this Java code to the code from other languages.

public class Java1541{

public static void main (String args[]){

System.out.println("\nJAVA1541.JAVA\n\n");for (int j = 20; j >= 0; j--){

if (j % 2 == 0){

System.out.println(j + " is an even number.");}else{

System.out.println(j + " is an odd number.");}

}System.out.println();

}}

// CPlusPlus.CPP// This program will count backwards from 20 to 0 and displays which numbers// are even and which are odd.// Compare this C++ code to the code from other languages.

#include <iostream.h>#include <conio.h>

void main(){ cout << endl << "CPlusPlus.CPP" << endl << endl; for (int j = 20; j >= 0; j--) {

if (j % 2 == 0){

cout << j << " is an even number." << endl;}else{

cout << j << " is an odd number." << endl;}

} cout << endl;

getch(); // makes the computer wait until a character is pressed}

{ Pascal.PAS This program will count backwards from 20 to 0 and displays which numbers are even and which are odd. Compare this Pascal code to the code from other languages. }

PROGRAM My_Pascal_Program;

VAR J : INTEGER; (* Loop Counter *)

BEGIN WRITELN; WRITELN('Pascal.PAS'); WRITELN; FOR J := 20 DOWNTO 0 DO BEGIN IF J MOD 2 = 0 THEN BEGIN WRITELN(J,' is an even number.') END ELSE BEGIN WRITELN(J,' is an odd number.') END END END.

Documents

Introduction