stripifier.java

JAVA3D矩陈的相关类

			swap = seq[len - 3];

			// find the neighboring strip
			int m = EMPTY;
			if (verts[0].index == swap.index) m = 0;
			else if (verts[1].index == swap.index) m = 1;
			else if (verts[2].index == swap.index) m = 2;
			if (m == EMPTY) {
			    if (DEBUG) System.out.println("problem finding neighbor strip");
			}
			int j = face.getNeighbor(m);
			if (j == EMPTY) id1 = j;
			else id1 = faceTable[j];
			if ((id1 != EMPTY) &&
			    (((Istream)strips.get(id1)).fan !=
			     strm.fan)) {
			    id1 = EMPTY;
			}

			if ((id1 != EMPTY) && (id1 != id)) {
			    strm1 = (Istream)strips.get(id1);
			    len1 = strm1.length;

			    // if the shared face isn't the head, invert
			    // the stream
			    if (j != strm1.head) {
				strm1.invert();
				// set the sync var if the length is odd
				if ((len1 % 2) != 0) sync1 = true;
			    }
			    seq1 = strm1.istream;

			    // append a singleton strip
			    if (len1 == 3) {
				//   				System.out.println("reduce2");
				m = faces[j].findSharedEdge(i);
				strm.append(faces[j].verts[m]);
				strm1.length = 0;
				strm1.istream = null;
				strm.tail = j;
				faceTable[i] = EMPTY;
				faceTable[j] = id;
			    }

			    // append a non-singleton strip
			    else {
				if ((len1 == 4) &&
				    (seq[len-2].index == seq1[0].index) &&
				    (seq[len-1].index == seq1[2].index)) {

				    // swap seq1[1] and seq1[2] so that
				    // seq[len-2] == seq1[0] and
				    // seq[len-1] == seq1[1]
				    swap = seq1[1];
				    seq1[1] = seq1[2];
				    seq1[2] = swap;
				}

				// see if we can append the strip
				if ((seq[len-2].index == seq1[0].index) &&
				    (seq[len-1].index == seq1[1].index)) {
				    //   				    System.out.println("reduce2");
				    strm.addStream(strm1);
				    faceTable[i] = EMPTY;
				    faceTable[strm.tail] = id;
				    faceTable[j] = EMPTY;
				}
				else if (sync1) strm1.invert();
			    }
			}
		    }
		}
	    }
	}
    }

    /**
     * find all links that reduce cost by 1
     */
    void reduceCostByOne(ArrayList strips, Face[] faces, int[] faceTable) {
	//  	System.out.println("reduceCostByOne");
	// number of faces in the face array
	int numFaces = faces.length;
	// possible adjacent strips
	int id, id1, id2;
	// Istreams
	Istream strm, strm1;
	// the length of the Istream
	int len, len1;
	// vertex sequences for tristrips
	Vertex[] seq, seq1;
	// a face
	Face face;
	// the list of vertices for the face
	Vertex[] verts;
	// used to synchronize the orientation
	boolean sync, sync1;
	// a swap variable
	Vertex swap;

	for (int i = 0; i < numFaces; i++) {
	    id = faceTable[i];
	    if ((id != EMPTY) && !((Istream)strips.get(id)).fan) {
		sync = false;
		strm = (Istream)strips.get(id);
		seq = strm.istream;
		face = faces[i];
		verts = face.verts;
		len = strm.length;

		// a singleton strip
		if (len == 3) {

		    // consider the three neighboring triangles
		    for (int j = 0; j < 3; j++) {
			int k = face.getNeighbor(j);
			if ((k != EMPTY) &&
			    ((id1 = faceTable[k]) != EMPTY) &&
			    (id1 != id) &&
			    (!((Istream)strips.get(id1)).fan)) {

			    // reassign the sequence
			    seq[0] = verts[j];
			    seq[1] = verts[(j+1)%3];
			    seq[2] = verts[(j+2)%3];

			    // the neighboring stream
			    strm1 = (Istream)strips.get(id1);
			    len1 = strm1.length;
			    if (k != strm1.head) {
				strm1.invert();
				if ((len1 % 2) != 0) sync = true;
			    }
			    seq1 = strm1.istream;

			    // see if we can join the strips

			    if ((len1 == 4) &&
				(((seq[1].index == seq1[2].index) &&
				  (seq[2].index == seq1[0].index)) ||
				 ((seq[1].index == seq1[0].index) &&
				  (seq[2].index == seq1[2].index)))) {
				swap = seq1[1];
				seq1[1] = seq1[2];
				seq1[2] = swap;
			    }

			    if ((seq[1].index == seq1[0].index) &&
				(seq[2].index == seq1[1].index)) {
				//  				System.out.println("reduce1");
				strm.addStream(strm1);
				faceTable[k] = EMPTY;
				faceTable[strm.tail] = id;
				i--;
				break;
			    }

			    if ((seq[1].index == seq1[1].index) &&
				(seq[2].index == seq1[0].index)) {
				//   				System.out.println("reduce1");
				strm.append(seq1[1]);
				strm.addStream(strm1);
				faceTable[k] = EMPTY;
				faceTable[strm.tail] = id;
				i--;
				break;
			    }

			    if ((seq[1].index == seq1[0].index) &&
				(seq[2].index == seq1[2].index)) {
				//   				System.out.println("reduce1");
				seq1[0] = seq1[2];
				strm.append(seq1[1]);
				strm.addStream(strm1);
				faceTable[k] = EMPTY;
				faceTable[strm.tail] = id;
				i--;
				break;
			    }

			    if (sync) {
				strm1.invert();
				sync = false;
			    }
			}
		    }
		}

		// non-singleton strip
		else if ((i == strm.tail) || ((len % 2) == 0)) {

		    // make sure the face i ends the id-th strip
		    if (i != strm.tail) {
			strm.invert();
			seq = strm.istream;
		    }

		    swap = seq[len-3];

		    // find the neighboring strip
		    int m = EMPTY;
		    if (verts[0].index == swap.index) m = 0;
		    else if (verts[1].index == swap.index) m = 1;
		    else if (verts[2].index == swap.index) m = 2;
		    if (m == EMPTY) {
			if (DEBUG) System.out.println("problem finding neighbor strip");
		    }
		    int j = face.getNeighbor(m);
		    if (j == EMPTY) id1 = j;
		    else id1 = faceTable[j];
		    if ((id1 != EMPTY) &&
			(((Istream)strips.get(id1)).fan != strm.fan)) {
			id1 = EMPTY;
		    }

		    // find another neighboring strip
		    swap = seq[len-2];
		    m = EMPTY;
		    if (verts[0].index == swap.index) m = 0;
		    else if (verts[1].index == swap.index) m = 1;
		    else if (verts[2].index == swap.index) m = 2;
		    if (m == EMPTY) {
			if (DEBUG) System.out.println("problem finding neighbor strip.");
		    }
		    int k = face.getNeighbor(m);
		    if (k == EMPTY) id2 = k;
		    else id2 = faceTable[k];
		    if ((id2 != EMPTY) &&
			(((Istream)strips.get(id2)).fan != strm.fan)) {
			id2 = EMPTY;
		    }

		    // consider strip id1
		    boolean success = false;
		    if ((id1 != EMPTY) && (id1 != id)) {
			strm1 = (Istream)strips.get(id1);
			len1 = strm1.length;
			if (j != strm1.head) {
			    strm1.invert();
			    if ((len1 % 2) != 0) sync = true;
			}
			seq1 = strm1.istream;

			if ((len1 == 4) &&
			    (((seq[len-2].index == seq1[2].index) &&
			      (seq[len-1].index == seq1[0].index)) ||
			     (seq[len-2].index == seq1[0].index) &&
			     (seq[len-1].index == seq1[2].index))) {
			    swap = seq1[1];
			    seq1[1] = seq1[2];
			    seq1[2] = swap;
			}

			// find matches
			if ((seq[len-2].index == seq1[0].index) &&
			    (seq[len-1].index == seq1[1].index)) {
			    //   			    System.out.println("reduce1");
			    strm.addStream(strm1);
			    faceTable[i] = EMPTY;
			    faceTable[strm.tail] = id;
			    faceTable[j] = EMPTY;
			    success = true;
			}

			else if ((seq[len-2].index == seq1[1].index) &&
				 (seq[len-1].index == seq1[0].index)) {
			    //   			    System.out.println("reduce1");
			    strm.append(seq1[1]);
			    strm.addStream(strm1);
			    faceTable[i] = EMPTY;
			    faceTable[strm.tail] = id;
			    faceTable[j] = EMPTY;
			    success = true;
			}

			else if ((seq[len-2].index == seq1[0].index) &&
				 (seq[len-1].index == seq1[2].index)) {
			    //   			    System.out.println("reduce1");
			    seq1[0] = seq1[2];
			    strm.append(seq1[1]);
			    strm.addStream(strm1);
			    faceTable[i] = EMPTY;
			    faceTable[strm.tail] = id;
			    faceTable[j] = EMPTY;
			    success = true;
			}
			else if (sync) {
			    strm1.invert();
			    sync = false;
			}
		    }

		    // now consider strip id2
		    if (!success &&
			(id2 != EMPTY) && (id2 != id)) {
			strm1 = (Istream)strips.get(id2);
			len1 = strm1.length;
			if (k != strm1.head) {
			    strm1.invert();
			    if ((len1 % 2) != 0) sync = true;
			}
			seq1 = strm1.istream;

			if ((len1 == 4) &&
			    (seq[len-3].index == seq1[0].index) &&
			    (seq[len-1].index == seq1[2].index)) {
			    swap = seq1[1];
			    seq1[1] = seq1[2];
			    seq1[2] = swap;
			}

			// find matches

			if ((seq[len-3].index == seq1[0].index) &&
			    (seq[len-1].index == seq1[1].index)) {
			    //   			    System.out.println("reduce1");
			    strm.swapEnd();
			    strm.addStream(strm1);
			    faceTable[i] = EMPTY;
			    faceTable[strm.tail] = id;
			    faceTable[k] = EMPTY;
			    success = true;
			}
			if (!success && sync) strm1.invert();
		    }
		}
	    }
	}
    }

    /**
     * find all the links that reduce the cost by 0
     */
    void reduceCostByZero(ArrayList strips, Face[] faces, int[] faceTable) {
	//  	System.out.println("reduceCostByZero");
	// number of faces in the face array
	int numFaces = faces.length;
	// possible adjacent strips
	int id, id1, id2;
	// Istreams
	Istream strm, strm1;
	// the length of the Istream
	int len, len1;
	// vertex sequences for tristrips
	Vertex[] seq, seq1;
	// a face
	Face face;
	// the list of vertices for the face
	Vertex[] verts;
	// used to synchronize the orientation
	boolean sync, sync1;
	// a swap variable
	Vertex swap;

	for (int i = 0; i < numFaces; i++) {
	    id = faceTable[i];
	    if ((id != EMPTY) && !((Istream)strips.get(id)).fan) {
		sync = false;
		strm = (Istream)strips.get(id);
		seq = strm.istream;
		len = strm.length;
		face = faces[i];
		verts = face.verts;

		if (len == 3) {
		    for (int j = 0; j < 3; j++) {
			int k = face.getNeighbor(j);
			if ((k != EMPTY) && ((id1 = faceTable[k]) != EMPTY) &&
			    (id1 != id) &&
			    !((Istream)strips.get(id1)).fan) {
			    // reassign the sequence
			    seq[0] = verts[j];
			    seq[1] = verts[(j+1)%3];
			    seq[2] = verts[(j+2)%3];

			    // the neighboring stream
			    strm1 = (Istream)strips.get(id1);
			    len1 = strm1.length;
			    if (k != strm1.head) {
				strm1.invert();
				if ((len1 % 2) != 0) sync = true;
			    }
			    seq1 = strm1.istream;

			    // see if we can join the strips
			    if ((seq[1].index == seq1[2].index) &&
				(seq[2].index == seq1[0].index)) {
				//   				System.out.println("reduce0");
				seq1[0] = seq1[2];
				strm.append(seq1[0]);
				strm.append(seq1[1]);
				strm.addStream(strm1);
				faceTable[k] = EMPTY;
				faceTable[strm.tail] = id;
				i--;
				break;
			    }
			    else if (sync) {
				strm1.invert();
				sync = false;
			    }
			}
		    }
		}
		else if ((i == strm.tail) || ((len % 2) == 0)) {
		    if (i != strm.tail) {
			strm.invert();
			seq = strm.istream;
		    }

		    swap = seq[len-3];

		    // find neighboring strip
		    int m = EMPTY;
		    if (verts[0].index == swap.index) m = 0;
		    else if (verts[1].index == swap.index) m = 1;
		    else if (verts[2].index == swap.index) m = 2;
		    if (m == EMPTY) {
			if (DEBUG) System.out.println("problem finding neighbor strip");
		    }
		    int j = face.getNeighbor(m);
		    if (j == EMPTY) id1 = j;
		    else id1 = faceTable[j];
		    if ((id1 != EMPTY) &&
			(((Istream)strips.get(id1)).fan != strm.fan)) {
			id1 = EMPTY;
		    }

		    // find another neighboring strip
		    swap = seq[len-2];
		    m = EMPTY;
		    if (verts[0].index == swap.index) m = 0;
		    else if (verts[1].index == swap.index) m = 1;
		    else if (verts[2].index == swap.index) m = 2;
		    if (m == EMPTY) {
			if (DEBUG) System.out.println("problem finding neighbor strip.");
		    }
		    int k = face.getNeighbor(m);
		    if (k == EMPTY) id2 = k;
		    else id2 = faceTable[k];
		    if ((id2 != EMPTY) &&
			(((Istream)strips.get(id2)).fan != strm.fan)) {
			id2 = EMPTY;
		    }

		    // consider strip id1
		    boolean success = false;
		    if ((id1 != EMPTY) && (id1 != id)) {
			strm1 = (Istream)strips.get(id1);
			len1 = strm1.length;
			if (j != strm1.head) {
			    strm1.invert();
			    if ((len1 % 2) != 0) sync = true;
			}
			seq1 = strm1.istream;

			// find matches
			if ((seq[len-2].index == seq1[2].index) &&
			    (seq[len-1].index == seq1[0].index)) {
			    //   			    System.out.println("reduce0");
			    seq1[0] = seq1[2];
			    strm.append(seq1[0]);
			    strm.append(seq1[1]);
			    strm.addStream(strm1);
			    faceTable[i] = EMPTY;
			    faceTable[strm.tail] = id;
			    faceTable[j] = EMPTY;
			    success = true;
			}
			else if (sync) {
			    strm1.invert();
			    sync = false;
			}
		    }

		    // consider strip id2
		    if (!success && (id2 != EMPTY) && (id2 != id)) {
			strm1 = (Istream)strips.get(id2);
			len1 = strm1.length;
			if (k != strm1.head) {
			    strm1.invert();
			    if ((len1 % 2) != 0) sync = true;
			}
			seq1 = strm1.istream;

			if ((len1 == 4) &&
			    (((seq[len-3].index == seq1[2].index) &&
			      (seq[len-1].index == seq1[0].index)) ||
			     ((seq[len-3].index == seq1[0].index) &&
			      (seq[len-1].index == seq1[2].index)))) {

			    swap = seq1[1];