sphere.java

JAVA3D矩陈的相关类

            }
        }
        
	shape = new Shape3D(gbuf.getGeom(flags));
	numVerts = gbuf.getNumVerts();
	numTris = gbuf.getNumTris();       
        
	if ((primflags & Primitive.GEOMETRY_NOT_SHARED) == 0) {
	    cacheGeometry(Primitive.SPHERE,
			  radius, 0.0f, 0.0f, 
			  divisions, 0, primflags, gbuf);
	}
    }

    if ((flags & ENABLE_APPEARANCE_MODIFY) != 0) {
	shape.setCapability(Shape3D.ALLOW_APPEARANCE_READ);
	shape.setCapability(Shape3D.ALLOW_APPEARANCE_WRITE);
    }

    if ((flags & ENABLE_GEOMETRY_PICKING) != 0) {
        shape.setCapability(Shape3D.ALLOW_GEOMETRY_READ);
    }
    
    this.addChild(shape);

    if (ap == null) {
      setAppearance();
    }
    else setAppearance(ap);
  }

    /**
     * Used to create a new instance of the node.  This routine is called
     * by <code>cloneTree</code> to duplicate the current node.
     * <code>cloneNode</code> should be overridden by any user subclassed
     * objects.  All subclasses must have their <code>cloneNode</code>
     * method consist of the following lines:
     * <P><blockquote><pre>
     *     public Node cloneNode(boolean forceDuplicate) {
     *         UserSubClass usc = new UserSubClass();
     *         usc.duplicateNode(this, forceDuplicate);
     *         return usc;
     *     }
     * </pre></blockquote>
     * @param forceDuplicate when set to <code>true</code>, causes the
     *  <code>duplicateOnCloneTree</code> flag to be ignored.  When
     *  <code>false</code>, the value of each node's
     *  <code>duplicateOnCloneTree</code> variable determines whether
     *  NodeComponent data is duplicated or copied.
     *
     * @see Node#cloneTree
     * @see Node#duplicateNode
     * @see NodeComponent#setDuplicateOnCloneTree
     */
    public Node cloneNode(boolean forceDuplicate) {
        Sphere s = new Sphere(radius, flags, divisions, getAppearance());
        s.duplicateNode(this, forceDuplicate);

        return s;
    }

    /**
     * Copies all node information from <code>originalNode</code> into
     * the current node.  This method is called from the
     * <code>cloneNode</code> method which is, in turn, called by the
     * <code>cloneTree</code> method.
     * <P>
     * For any <i>NodeComponent</i> objects
     * contained by the object being duplicated, each <i>NodeComponent</i>
     * object's <code>duplicateOnCloneTree</code> value is used to determine
     * whether the <i>NodeComponent</i> should be duplicated in the new node
     * or if just a reference to the current node should be placed in the
     * new node.  This flag can be overridden by setting the
     * <code>forceDuplicate</code> parameter in the <code>cloneTree</code>
     * method to <code>true</code>.
     *
     * @param originalNode the original node to duplicate.
     * @param forceDuplicate when set to <code>true</code>, causes the
     *  <code>duplicateOnCloneTree</code> flag to be ignored.  When
     *  <code>false</code>, the value of each node's
     *  <code>duplicateOnCloneTree</code> variable determines whether
     *  NodeComponent data is duplicated or copied.
     *
     * @see Node#cloneTree
     * @see Node#cloneNode
     * @see NodeComponent#setDuplicateOnCloneTree
     */
    public void duplicateNode(Node originalNode, boolean forceDuplicate) {
        super.duplicateNode(originalNode, forceDuplicate);
    }

    /**
     * Returns the radius of the sphere
     *
     * @since Java 3D 1.2.1
     */
    public float getRadius() {
	return radius;
    }

    /**
     * Returns the number of divisions
     *
     * @since Java 3D 1.2.1
     */
    public int getDivisions() {
	return divisions;
    }

    void buildQuadrant(GeomBuffer gbuf, double startDelta, double endDelta,
		       int sign, int nstep, int n, boolean upperSphere)
    {
	
	double ds, dt, theta, delta;
	int i, j, index, i2;
	double h, r, vx, vz;
	Point3f pt;
	Vector3f norm;
	TexCoord2f texCoord;
	double starth;
	double t;
	boolean leftToRight;


	if (upperSphere) {
            dt = Math.PI/(2*nstep);
            theta = dt;
            starth = 1;
	    leftToRight = (sign > 0);
        } else {
            dt = -Math.PI/(2*nstep);
            theta = Math.PI + dt;
            starth = -1;
	    leftToRight = (sign < 0);
        }
	

	for (i = 1; i <= nstep; i++) {
	    h = Math.cos(theta);
	    r = Math.sin(theta);
	    if (sign > 0) {
		t = 1 - theta/Math.PI;
	    } else {
		t = theta/Math.PI;
	    }

	    i2 = i << 1;
	    // subdivision decreases towards the pole
	    ds =  (endDelta - startDelta) / i;

	    gbuf.begin(GeomBuffer.TRIANGLE_STRIP);	  

	    if (leftToRight) {
		// Build triangle strips from left to right
		delta =  startDelta;

		for (j=0; j < i; j++) {
		    vx = r*Math.cos(delta);
		    vz = r*Math.sin(delta);

		    gbuf.normal3d( vx*sign, h*sign, vz*sign );
		    gbuf.texCoord2d(0.75 - delta/(2*Math.PI), t);
		    gbuf.vertex3d( vx*radius, h*radius, vz*radius );
		    if (i > 1) {
			// get previous vertex from buffer
			index = gbuf.currVertCnt - i2;
			pt = gbuf.pts[index];
			norm = gbuf.normals[index];
			texCoord = gbuf.tcoords[index];
			// connect with correspondent vertices from previous row
			gbuf.normal3d(norm.x, norm.y, norm.z);
			gbuf.texCoord2d(texCoord.x, texCoord.y);
			gbuf.vertex3d(pt.x, pt.y, pt.z);
		    } else {
			gbuf.normal3d(0, sign*starth, 0);
			if (sign > 0) {
			    gbuf.texCoord2d(0.75 - (startDelta + endDelta)/(4*Math.PI), 
					    1.0 - (theta - dt)/Math.PI);
			} else {
			    gbuf.texCoord2d(0.75 - (startDelta + endDelta)/(4*Math.PI), 
					    (theta - dt)/Math.PI);
			}
                        gbuf.vertex3d( 0, starth*radius, 0); 
			
		    }
		    delta += ds;
		}

		// Put the last vertex in that row,
		// for numerical accuracy we don't use delta
		// compute from above. 
		delta = endDelta;
		vx = r*Math.cos(delta);
		vz = r*Math.sin(delta);
		gbuf.normal3d( vx*sign, h*sign, vz*sign );
		gbuf.texCoord2d(0.75 - delta/(2*Math.PI), t);
		gbuf.vertex3d( vx*radius, h*radius, vz*radius);
	    } else {
		delta =  endDelta;
		// Build triangle strips from right to left
		for (j=i; j > 0; j--) {
		    vx = r*Math.cos(delta);
		    vz = r*Math.sin(delta);
		    
		    gbuf.normal3d( vx*sign, h*sign, vz*sign );
		    // Convert texture coordinate back to one
		    // set in previous version 
		    gbuf.texCoord2d(0.75 - delta/(2*Math.PI), t);
		    gbuf.vertex3d( vx*radius, h*radius, vz*radius );
		    if (i > 1) {
			// get previous vertex from buffer
			index = gbuf.currVertCnt - i2;
			pt = gbuf.pts[index];
			norm = gbuf.normals[index];
			texCoord = gbuf.tcoords[index];
			gbuf.normal3d(norm.x, norm.y, norm.z);
			gbuf.texCoord2d(texCoord.x, texCoord.y);
			gbuf.vertex3d(pt.x, pt.y, pt.z);
		    } else {
			gbuf.normal3d(0, sign*starth, 0);
			if (sign > 0) {
			    gbuf.texCoord2d(0.75 - (startDelta + endDelta)/(4*Math.PI), 
					    1.0 - (theta - dt)/Math.PI);
			} else {
			    gbuf.texCoord2d(0.75 - (startDelta + endDelta)/(4*Math.PI), 
					    (theta - dt)/Math.PI);			    
			}
                        gbuf.vertex3d( 0, starth*radius, 0);      

		    }
		    delta -= ds;
		}

		// Put the last vertex in that row,
		// for numerical accuracy we don't use delta
		// compute from above. 
		delta = startDelta;
		vx = r*Math.cos(delta);
		vz = r*Math.sin(delta);
		gbuf.normal3d( vx*sign, h*sign, vz*sign );
		gbuf.texCoord2d(0.75 - delta/(2*Math.PI), t);
		gbuf.vertex3d( vx*radius, h*radius, vz*radius );	    

	    } 

	    gbuf.end();

	    if (i < nstep) {
		theta += dt;
	    } else { // take care of numerical imprecision
		theta = Math.PI/2;
	    }
	}

    }
}