RGB values are in the 0255 range import javaawt import javaapplet public class

Rgb values are in the 0255 range import javaawt

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// RGB values are in the [0..255] range. import java.awt.*; import java.applet.*; public class Java0620 extends Applet { public void paint(Graphics g) { g.setColor(new Color(255,0,255)); g.fillRect(0,0,800,200); g.setColor(new Color(0,255,255)); g.fillRect(0,200,800,200); g.setColor(new Color(100,100,100)); g.fillRect(0,400,800,200); } }
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// Java0621.java // This program shows all the shades of Red, Green and Blue using the <setColor> method. import java.awt.*; import java.applet.*; public class Java0621 extends Applet { public void paint(Graphics g) { for (int red = 0; red <= 255; red++) { g.setColor(new Color(red,0,0)); g.drawLine(red,0,red,600); } for (int green = 0; green <= 255; green++) { g.setColor(new Color(0,green,0)); g.drawLine(green+255,0,green+255,600); } for (int blue = 0; blue <= 255;blue++) { g.setColor(new Color(0,0,blue)); g.drawLine(blue+510,0,blue+510,600); } } }
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// Java0622.java // This program draws three squares with user-defined <Color> objects. import java.awt.*; import java.applet.*; public class Java0622 extends Applet { public void paint(Graphics g) { Color myRed = new Color(255,0,64); Color myGreen = new Color(16,255,16); Color myBlue = new Color(64,64,255); g.setColor(myRed); g.fillRect(20,100,100,100); g.setColor(myGreen); g.fillRect(140,100,100,100); g.setColor(myBlue); g.fillRect(260,100,100,100); } }
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Anonymous Objects Situations exist where an object identifier is not necessary when creating a new object. The majority of objects have an object identifier like these two examples: Bank tom = new Bank(2500); Color myRed = new Color(255,0,64); There are also objects that are used as parameters in a method call like: g.setColor(new Color(100,100,100)); A new Color object is created, but not identified. Such objects are called anonymous objects.
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1. Load Paint 2. Click [Colors] - [Edit Colors] - [Define Custom Colors] 3. Click the triangle at the right side of the window 4. Move the crosshairs and triangle until you get the color you want in the Color/Solid box. 5. Copy the Red , Green , and Blue numbers into your java program. 6. Ignore the Hue, Sat, and Lum!
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// Java0622.java // Try This! Add your customized color! public class Java0622 extends Applet { public void paint(Graphics g) { Color myRed = new Color(255,0,64); Color myGreen = new Color(16,255,16); Color myBlue = new Color(64,64,255); Color myBrown = new Color(150,100,15); g.setColor(myRed); g.fillRect(20,100,100,100); g.setColor(myGreen); g.fillRect(140,100,100,100); g.setColor(myBlue); g.fillRect(260,100,100,100); g.setColor(myBrown); g.fillRect(380,100,100,100); } }
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Special Note for People Who Create Web Pages This same technique can be used to pick colors for a web page. If you ever do a View - Page Source on a web page, you may see something like: The second line shows the same RGB (red, green, blue) values are used in the same way that we did in Java. The third line also uses RGB (red, green, blue) values, but these are base 16 (Hexadecimal) numbers. Either method works. Chapter 16 will discuss Number Systems .
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Drawing Polygons Java has some special features to draw polygons. The Graphics class provides two methods, drawPolygon and fillPolygon . Before you draw any polygon, you must first create an object of the Polygon class. The Polygon class has an addPoint method.
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