exbackgroundcolor.java

详细介绍Java 3D编程的一本电子书

//
//  CLASS
//    ExBackgroundColor  -  illustrate use of colored Backgrounds
//
//  LESSON
//    Add a Background node to set the background color.
//
//  SEE ALSO
//    ExBackgroundImage
//    ExBackgroundGeometry
//
//  AUTHOR
//    David R. Nadeau / San Diego Supercomputer Center
//

import java.awt.*;
import java.awt.event.*;
import javax.media.j3d.*;
import javax.vecmath.*;
import com.sun.j3d.utils.image.*;

public class ExBackgroundColor
	extends Example
{
	//--------------------------------------------------------------
	//  SCENE CONTENT
	//--------------------------------------------------------------

	//
	//  Nodes (updated via menu)
	//
	private Background background = null;

	//
	//  Build scene
	//
	public Group buildScene( )
	{
		// Get the current color
		Color3f color = (Color3f)colors[currentColor].value;

		// Turn off the example headlight
		setHeadlightEnable( false );

		// Default to walk navigation
		setNavigationType( Walk );

		// Create the scene group
		Group scene = new Group( );


	// BEGIN EXAMPLE TOPIC
		// Create application bounds
		BoundingSphere worldBounds = new BoundingSphere(
			new Point3d( 0.0, 0.0, 0.0 ),  // Center
			1000.0 );                      // Extent

		// Set the background color and its application bounds
		background = new Background( );
		background.setColor( color );
		background.setCapability( Background.ALLOW_COLOR_WRITE );
		background.setApplicationBounds( worldBounds );
		scene.addChild( background );
	// END EXAMPLE TOPIC


		// Build foreground geometry
		scene.addChild( new TowerScene( this ) );

		return scene;
	}



	//--------------------------------------------------------------
	//  USER INTERFACE
	//--------------------------------------------------------------

	//
	//  Main
	//
	public static void main( String[] args )
	{
		ExBackgroundColor ex = new ExBackgroundColor( );
		ex.initialize( args );
		ex.buildUniverse( );
		ex.showFrame( );
	}


	//  Color menu choices
	private NameValue[] colors = {
		new NameValue( "White",      White ),
		new NameValue( "Dark Gray",  DarkGray ),
		new NameValue( "Black",      Black ),
		new NameValue( "Dark Red",   DarkRed ),
		new NameValue( "Dark Green", DarkGreen ),
		new NameValue( "Dark Blue",  DarkBlue ),
	};
	private int currentColor = 2;
	private CheckboxMenu colorMenu = null;


	//
	//  Initialize the GUI (application and applet)
	//
	public void initialize( String[] args )
	{
		// Initialize the window, menubar, etc.
		super.initialize( args );
		exampleFrame.setTitle( "Java 3D Background Color Example" );


		//
		//  Add a menubar menu to change node parameters
		//    Color -->
		//

		Menu m = new Menu( "Background" );

		colorMenu = new CheckboxMenu( "Color", colors,
			currentColor, this );
		m.add( colorMenu );

		exampleMenuBar.add( m );
	}


	//
	//  Handle checkboxes and menu choices
	//
	public void checkboxChanged( CheckboxMenu menu, int check )
	{
		if ( menu == colorMenu )
		{
			// Change the light color
			currentColor = check;
			Color3f color = (Color3f)colors[check].value;
			background.setColor( color );
			return;
		}

		// Handle all other checkboxes
		super.checkboxChanged( menu, check );
	}
}