Do great artists plan their art before they start working?

 

 

 

houseGraph.gif (8644 bytes)

 

 

A good answer might be:

You should get something like this:

  1. House --- ( 65, 100) width=110, height=110
  2. Door --- (120, 165) width= 25, height= 40
  3. Left Window --- ( 90, 115) width= 30, height= 30
  4. Right Window --- (130, 115) width= 30, height= 30
  5. Tree Trunk --- (255, 100) width= 10, height=100

 

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

// assume that the drawing area is 350 by 250
public class tenCircles extends Applet
{
  final int width = 350, height = 250;
  final int houseX = ________, houseY = ______, houseW = _______, houseH = ______ ;
  final int doorX  = ________, doorY  = ______, doorW  = _______, doorH  = ______ ;
  final int lWindX = ________, lWindY = ______, lWindW = _______, lWindH = ______ ;
  final int rWindX = ________, rWindY = ______, rWindW = _______, rWindH = ______ ;
  final int trunkX = ________, trunkY = ______, trunkW = _______, trunkH = ______ ;
  
  public void paint ( Graphics gr )
  { 

     gr.drawRect(                                  ); // house
     gr.drawRect(                                  ); // door
     gr.drawRect(                                  ); // lwind
     gr.drawRect(                                  ); // rwind
     gr.drawRect(                                  ); // trunk
  }
}

 

 

 

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

// assume that the drawing area is 350 by 250
public class houseRectangles extends Applet
{
  final int width  = 350, height = 250;
  final int houseX =  65, houseY = 100, houseW = 110, houseH = 110 ;
  final int doorX  = 120, doorY  = 165, doorW  =  25, doorH  =  40 ;
  final int lWindX =  90, lWindY = 115, lWindW =  30, lWindH =  30 ;
  final int rWindX = 130, rWindY = 115, rWindW =  30, rWindH =  30 ;
  final int trunkX = 255, trunkY = 100, trunkW =  10, trunkH = 100 ;
  
  public void paint ( Graphics gr )
  { 
     gr.setColor( Color.orange );    // there is no Color brown
     gr.drawRect( houseX , houseY , houseW, houseH); // house
     gr.drawRect( doorX  , doorY  , doorW , doorH ); // door
     gr.drawRect( lWindX , lWindY , lWindW, lWindH); // lwind
     gr.drawRect( rWindX , rWindY , rWindW, rWindH); // rwind
     gr.fillRect( trunkX , trunkY , trunkW, trunkH); // trunk
  }
}

 

 

Calculating a Coordinate

 

  

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

// assume that the drawing area is 350 by 250
public class houseComplete extends Applet
{
  final int width  = 350, height = 250;
  final int houseX =  65, houseY = 100, houseW = 110, houseH = 110 ;
  final int               doorY  = 165, doorW  =  25, doorH  =  40 ;
  final int lWindX =  90, lWindY = 115, lWindW =  30, lWindH =  30 ;
  final int rWindX = 130, rWindY = 115, rWindW =  30, rWindH =  30 ;
  final int trunkX = 255, trunkY = 100, trunkW =  10, trunkH = 100 ;
  final int treeX  = 200, treeY  =  45, treeW  = 125, treeH  =  55 ;  // tree leaves 
  
  final int L1X1   = 0,             L1Y1 = 140,    L1X2 = 40,      L1Y2 = 115; 
  final int L2X1   = L1X2,          L2Y1 = L1Y2,   L2X2 = houseX,  L2Y2 = 130;
  final int L3X1   = houseX+houseW, L3Y1 = 135,    L3X2 = trunkX,  L3Y2 = 140;
  final int L4X1   = trunkX+trunkW, L4Y1 = L3Y2,   L4X2 = width,   L4Y2 = 110;

  final int roof1X1 = houseX,  roof1Y1 = houseY;
  final int roof1X2 = houseX + houswW/2, roof1Y2 = 50;
  final int roof2X1 = roof1X2, roof2Y1 = roof1Y2;
  final int roof2X2 = houseX + houswW, roof2Y2 = houseY;
  final int doorX   = houseX + houseW/2 - doorW/2;
  
  public void paint ( Graphics gr )
  { 
     gr.setColor( Color.orange );                    // there is no brown
     gr.drawRect( houseX , houseY , houseW, houseH); // house
     gr.fillRect( doorX  , doorY  , doorW , doorH ); // door
     gr.drawRect( lWindX , lWindY , lWindW, lWindH); // lwind
     gr.drawRect( rWindX , rWindY , rWindW, rWindH); // rwind
     gr.fillRect( trunkX , trunkY , trunkW, trunkH); // trunk
     
     gr.setColor( Color.green );
     gr.fillOval( treeX, treeY, treeW, treeH ); 

     gr.drawLine( L1X1, L1Y1, L1X2, L1Y2 ); // line 1
     gr.drawLine( L2X1, L2Y1, L2X2, L2Y2 ); // line 2
     gr.drawLine( L3X1, L3Y1, L3X2, L3Y2 ); // line 3
     gr.drawLine( L4X1, L4Y1, L4X2, L4Y2 ); // line 4

     gr.setColor( Color.green );
     gr.drawLine( roof1X1, roof1Y1, roof1X2, roof1Y2 );
     gr.drawLine( roof2X1, roof2Y1, roof2X2, roof2Y2 );
  }
}

 

How could you draw ten red circles across an applet's drawing area?

 

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

// assume that the drawing area is 300 by 150
public class tenCircles extends Applet
{
  final int width = 300, height = 150;

  public void paint ( Graphics gr )
  { 
    int count = _________________;

    while ( _________________ )
    {


      _________________
    }

  }
}

Let us write the program by using a loop. Remember, it is often a good idea to think about what you are doing one piece at a time. When there is a loop in a program, it it often helpful to start with it. Here is a skeleton of the program:

This skeleton has most of what is needed. It has:

This is quite a bit to start with, and should not be ignored.

 


 

 

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

// Assume that the drawing area is 300 by 150.
// Draw ten red circles side-by-side across the drawing area.
public class tenCircles extends Applet
{
  final int width = 300, height = 150;

  public void paint ( Graphics gr )
  { 
    gr.setColor( Color.red );

    int count =  0 ;
    while (  count < 10  )
    {
      int radius = (width/10)/2;      // the diameter is width/10

      int X      = count*(width/10);  // the left edge of each of 10
                                      // squares across the area
      int Y      = height/2 - radius; // the top edge of the squares

      gr.drawOval( X, Y, 2*radius, 2*radius );
      count = count + 1; 
    }

  }
}