/*------------*/
/* Ja61.java  */
/*------------*/
import java.applet.Applet;
import java.awt.*;                          //BorderLayout,GraphicsConfiguration,event
import javax.media.j3d.*;                   //Java3d
import com.sun.j3d.utils.applet.MainFrame;  //MainFrame
import com.sun.j3d.utils.universe.*;        //SimpleUniverse
import com.sun.j3d.utils.behaviors.mouse.*; //Mouse
import javax.vecmath.*;                     //Point3f,Color3f

public class Ja61 extends Applet{

    private SimpleUniverse simpleU;
    private BoundingSphere bounds = new BoundingSphere(new Point3d(), 10.0);

    public void init(){

        //アプレットの中央にCanvas3Dを追加
        setLayout(new BorderLayout());
        Canvas3D canvas = new Canvas3D(SimpleUniverse.getPreferredConfiguration());
        add(canvas, BorderLayout.CENTER);

        //シーングラフの生成
        simpleU = new SimpleUniverse(canvas);
        simpleU.getViewingPlatform().setNominalViewingTransform();

        //シーングラフの作成
        simpleU.addBranchGraph(createSceneGraph());
    }

    private BranchGroup createSceneGraph(){

        BranchGroup branchG0 = new BranchGroup();

        //背景色の設定（設定が無い場合は黒）
        Background background = new Background(new Color3f(0.3f, 0.3f, 0.3f));
        background.setApplicationBounds(bounds);
        branchG0.addChild(background);

        //光源を追加
        branchG0.addChild(createDirectionalLight());

        //マウス操作用のノード
        TransformGroup transG0 = new TransformGroup();
        branchG0.addChild(transG0);

        //四角形ポリゴンのAppearanceを作成
        Appearance ap = new Appearance();
        PolygonAttributes pa = new PolygonAttributes();
        pa.setCullFace(PolygonAttributes.CULL_NONE);        //裏面も表示する
        pa.setBackFaceNormalFlip(true);                     //裏面にも法線設定
        ap.setPolygonAttributes(pa);
        ColoringAttributes ca = new ColoringAttributes();
        ca.setColor(new Color3f( 0.0f, 0.0f, 1.0f));        //青色
        ap.setColoringAttributes(ca);
        Material ma = new Material();                       //Materialを作成
        ap.setMaterial(ma);                                 //デフォルト白色

        //四角形ポリゴンの頂点座標設定
        Point3f[] vertex = new Point3f[4];
        vertex[0] = new Point3f( 0.5f,  0.5f, 0.0f);
        vertex[1] = new Point3f(-0.5f,  0.5f, 0.0f);
        vertex[2] = new Point3f(-0.5f, -0.5f, 0.0f);
        vertex[3] = new Point3f( 0.5f, -0.5f, 0.0f);
        QuadArray quadA
            = new QuadArray(vertex.length,
                GeometryArray.COORDINATES | GeometryArray.NORMALS);  //法線情報追加
        quadA.setCoordinates(0, vertex);
        Vector3f normal = new Vector3f(0.0f, 0.0f, 1.0f);   //頂点の法線を設定する
        normal.normalize();                                 //規格化
        for(int i=0; i<4; i++){                             //各頂点に法線を設定する
            quadA.setNormal(i, normal);
        }
        Shape3D quad3D = new Shape3D(quadA, ap);
        transG0.addChild(quad3D);

        //参考の為に法線を書く
        transG0.addChild(drawNormal(new Point3f(0.0f, 0.0f, 0.0f), normal));

        //マウスによる物体移動
        transG0.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);
        transG0.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
        MouseRotate mouseRot = new MouseRotate(transG0);
        mouseRot.setSchedulingBounds(bounds);
        transG0.addChild(mouseRot);

        branchG0.compile();

        return branchG0;
    }

    //平行光源を作成する
    private Light createDirectionalLight(){

        DirectionalLight lightD = new DirectionalLight();   //デフォルトの平行光源
        lightD.setInfluencingBounds(bounds);                //光が影響する範囲

        return lightD;
    }

    //法線を作成する
    private Shape3D drawNormal(Point3f point1, Vector3f vec){

        Point3f point2 = new Point3f(point1);
        Point3f[] vertex = new Point3f[2];
        Color3f[] color = new Color3f[2];

        vec.scale(0.5f);
        point2.add(vec);

        vertex[0] = point1;
        vertex[1] = point2;
        color[0] = new Color3f( 1.0f, 1.0f, 0.0f);
        color[1] = new Color3f( 1.0f, 1.0f, 0.0f);

        LineArray lineA
            = new LineArray(vertex.length,
                GeometryArray.COORDINATES | GeometryArray.COLOR_3);
        lineA.setCoordinates(0, vertex);
        lineA.setColors(0, color);
        Shape3D line3D = new Shape3D(lineA);

        return line3D;
    }

    public void destroy(){

        simpleU.cleanup();
    }

    public static void main(String[] args){    //Application

        MainFrame frame = new MainFrame(new Ja61(), 512, 512);
    }
}