columnscene.java

JAVA网络三维技术3D的设计与实现

//
//  CLASS
//    ColumnScene	-  shapes and lights for a scene with gothic columns
//
//  DESCRIPTION
//    This class builds a scene containing a stone floor, a set of
//    marble columns, plus appropriate lighting.  The scene is used in
//    several of the examples to provide content to affect with lights,
//    background colors and images, and so forth.
//
//  SEE ALSO
//    ExExponentialFog
//    ExLinearFog
//
//  AUTHOR
//    David R. Nadeau / San Diego Supercomputer Center
//
package Java3DApplet;
import java.awt.*;
import java.awt.event.*;
import javax.media.j3d.*;
import javax.vecmath.*;
import com.sun.j3d.utils.image.*;

public class ColumnScene
	extends Group
{
	//--------------------------------------------------------------
	//  SCENE CONTENT
	//--------------------------------------------------------------

	// Construction parameters
	private final static float ColumnHeight = 3.0f;
	private final static float ColumnRadius = 0.2f;
	private final static float ColumnDepthSpacing = 6.0f;
	private final static float ColumnSideOffset = 1.0f;
	private final static int   NumberOfColumns = 4;
	private final static float WalkwayWidth = 3.0f;
	private final static float WalkwayDepth = ((float)NumberOfColumns-1) * ColumnDepthSpacing + 4.0f * WalkwayWidth;
	private final static float LawnWidth = 4.0f * WalkwayWidth;
	private final static float LawnDepth = WalkwayDepth;
	private Texture columnTex = null;


	//
	//  Build a single column in a shared group
	//
	private SharedGroup buildSharedColumn( )
	{
		Appearance columnApp = new Appearance( );

		Material columnMat = new Material( );
		columnMat.setAmbientColor( 0.6f, 0.6f, 0.6f );
		columnMat.setDiffuseColor( 1.0f, 1.0f, 1.0f );
		columnMat.setSpecularColor( 0.0f, 0.0f, 0.0f );
		columnApp.setMaterial( columnMat );

		TextureAttributes columnTexAtt = new TextureAttributes( );
		columnTexAtt.setTextureMode( TextureAttributes.MODULATE );
		columnTexAtt.setPerspectiveCorrectionMode( TextureAttributes.NICEST);
		columnApp.setTextureAttributes( columnTexAtt );

		if ( columnTex != null )
			columnApp.setTexture( columnTex );

		GothicColumn columnShape = new GothicColumn(
			ColumnHeight,  // height
			ColumnRadius,  // radius
			GothicColumn.BUILD_TOP,  // flags
			columnApp );   // appearance

	// BEGIN EXAMPLE TOPIC
		// Build a shared group to hold the column shape
		SharedGroup column = new SharedGroup( );
		column.addChild( columnShape );
	// END EXAMPLE TOPIC

		return column;
	}


	//
	//  Used a column in a shared group and link to it
	//  several times to build a double row of columns
	//
	private Group buildColumns( SharedGroup column )
	{
		Group group = new Group( );

		// Place columns
		float x = -ColumnSideOffset;
		float y = -1.6f;
		float z =  ColumnDepthSpacing;
		float xSpacing = 2.0f * ColumnSideOffset;
		float zSpacing = -ColumnDepthSpacing;

	// BEGIN EXAMPLE TOPIC
		Vector3f trans = new Vector3f( );
		Transform3D tr = new Transform3D( );
		TransformGroup tg;

		for ( int i = 0; i < NumberOfColumns; i++ )
		{
			// Left link
			trans.set( x, y, z );
			tr.set( trans );
			tg = new TransformGroup( tr );
			tg.addChild( new Link( column ) );
			group.addChild( tg );

			// Right link
			trans.set( x+xSpacing, y, z );
			tr.set( trans );
			tg = new TransformGroup( tr );
			tg.addChild( new Link( column ) );
			group.addChild( tg );

			z += zSpacing;
		}
	// END EXAMPLE TOPIC

		return group;
	}


	//
	//  Build a scene containing multiple columns
	//
	public ColumnScene( Component observer )
	{
		BoundingSphere worldBounds = new BoundingSphere(
			new Point3d( 0.0, 0.0, 0.0 ),  // Center
			1000.0 );                      // Extent

		// Add a few lights
		AmbientLight ambient = new AmbientLight( );
		ambient.setEnable( true );
		ambient.setColor( new Color3f( 0.2f, 0.2f, 0.2f ) );
		ambient.setInfluencingBounds( worldBounds );
		addChild( ambient );

		DirectionalLight dir1 = new DirectionalLight( );
		dir1.setEnable( true );
		dir1.setColor( new Color3f( 1.0f, 1.0f, 1.0f ) );
		dir1.setDirection( new Vector3f( 0.8f, -0.35f, 0.5f ) );
		dir1.setInfluencingBounds( worldBounds );
		addChild( dir1 );

		DirectionalLight dir2 = new DirectionalLight( );
		dir2.setEnable( true );
		dir2.setColor( new Color3f( 0.75f, 0.75f, 1.0f ) );
		dir2.setDirection( new Vector3f( -0.7f, -0.35f, -0.5f ) );
		dir2.setInfluencingBounds( worldBounds );
		addChild( dir2 );


		// Load textures
		TextureLoader texLoader = new TextureLoader( "grass06.jpg", observer );
		Texture grassTex = texLoader.getTexture( );
		if ( grassTex == null )
			System.err.println( "Cannot load grass06.jpg texture" );
		else
		{
			grassTex.setBoundaryModeS( Texture.WRAP );
			grassTex.setBoundaryModeT( Texture.WRAP );
			grassTex.setMinFilter( Texture.NICEST );
			grassTex.setMagFilter( Texture.NICEST );
			grassTex.setMipMapMode( Texture.BASE_LEVEL );
			grassTex.setEnable( true );
		}

		texLoader = new TextureLoader( "marble10.jpg", observer );
		Texture walkTex = texLoader.getTexture( );
		if ( walkTex == null )
			System.err.println( "Cannot load marble10.jpg texture" );
		else
		{
			walkTex.setBoundaryModeS( Texture.WRAP );
			walkTex.setBoundaryModeT( Texture.WRAP );
			walkTex.setMinFilter( Texture.NICEST );
			walkTex.setMagFilter( Texture.NICEST );
			walkTex.setMipMapMode( Texture.BASE_LEVEL );
			walkTex.setEnable( true );
		}

		texLoader = new TextureLoader( "granite07rev.jpg", observer );
		columnTex = texLoader.getTexture( );
		if ( columnTex == null )
			System.err.println( "Cannot load granite07rev.jpg texture" );
		else
		{
			columnTex.setBoundaryModeS( Texture.WRAP );
			columnTex.setBoundaryModeT( Texture.WRAP );
			columnTex.setMinFilter( Texture.NICEST );
			columnTex.setMagFilter( Texture.NICEST );
			columnTex.setMipMapMode( Texture.BASE_LEVEL );
			columnTex.setEnable( true );
		}


		//
		//  Build the ground
		//    +-----+---+-----+
		//    |     |   |     |
		//    |  G  | W |  G  |
		//    |     |   |     |
		//    +-----+---+-----+
		//
		//  where "G" is grass, and "W" is a walkway between columns
		//
		Vector3f trans = new Vector3f( );
		Transform3D tr = new Transform3D( );
		TransformGroup tg;

		//  Walkway appearance
		Appearance walkApp = new Appearance( );

		Material walkMat = new Material( );
		walkMat.setAmbientColor( 0.5f, 0.5f, 0.5f );
		walkMat.setDiffuseColor( 1.0f, 1.0f, 1.0f );
		walkMat.setSpecularColor( 0.0f, 0.0f, 0.0f );
		walkApp.setMaterial( walkMat );

		TextureAttributes walkTexAtt = new TextureAttributes( );
		walkTexAtt.setTextureMode( TextureAttributes.MODULATE );
		walkTexAtt.setPerspectiveCorrectionMode( TextureAttributes.NICEST );
		tr.setIdentity( );
		tr.setScale( new Vector3d( 1.0, 6.0, 1.0 ) );
		walkTexAtt.setTextureTransform( tr );
		walkApp.setTextureAttributes( walkTexAtt );

		if ( walkTex != null )
			walkApp.setTexture( walkTex );


		//  Grass appearance
		Appearance grassApp = new Appearance( );

		Material grassMat = new Material( );
		grassMat.setAmbientColor( 0.5f, 0.5f, 0.5f );
		grassMat.setDiffuseColor( 1.0f, 1.0f, 1.0f );
		grassMat.setSpecularColor( 0.0f, 0.0f, 0.0f );
		grassApp.setMaterial( grassMat );

		TextureAttributes grassTexAtt = new TextureAttributes( );
		grassTexAtt.setTextureMode( TextureAttributes.MODULATE );
		grassTexAtt.setPerspectiveCorrectionMode( TextureAttributes.NICEST );
		tr.setIdentity( );
		tr.setScale( new Vector3d( 2.0, 8.0, 1.0 ) );
		grassTexAtt.setTextureTransform( tr );
		grassApp.setTextureAttributes( grassTexAtt );

		if ( grassTex != null )
			grassApp.setTexture( grassTex );


		//  Left grass
		trans.set( -LawnWidth/2.0f - WalkwayWidth/2.0f, -1.6f, 0.0f );
		tr.set( trans );
		tg = new TransformGroup( tr );
		ElevationGrid grass1 = new ElevationGrid(
			2,             // X dimension
			2,             // Z dimension
			LawnWidth,     // X spacing
			LawnDepth,     // Z spacing
			grassApp );    // appearance
		tg.addChild( grass1 );
		addChild( tg );

		//  Right grass
		trans.set( LawnWidth/2.0f + WalkwayWidth/2.0f, -1.6f, 0.0f );
		tr.set( trans );
		tg = new TransformGroup( tr );
		ElevationGrid grass2 = new ElevationGrid(
			2,             // X dimension
			2,             // Z dimension
			LawnWidth,     // X spacing
			LawnDepth,     // Z spacing
			grassApp );    // appearance
		tg.addChild( grass2 );
		addChild( tg );

		//  Walkway
		trans.set( 0.0f, -1.6f, 0.0f );
		tr.set( trans );
		tg = new TransformGroup( tr );
		ElevationGrid walk = new ElevationGrid(
			2,             // X dimension
			2,             // Z dimension
			WalkwayWidth,  // X spacing
			WalkwayDepth,  // Z spacing
			walkApp );     // appearance
		tg.addChild( walk );
		addChild( tg );


		//
		// Build several columns on the floor
		//
		SharedGroup column = buildSharedColumn( );
		Group columns = buildColumns( column );
		addChild( columns );
	}
}