/* 
   * PROJECT: FLARToolKit
   * --------------------------------------------------------------------------------
   * This work is based on the NyARToolKit developed by
   *   R.Iizuka (nyatla)
   * http://nyatla.jp/nyatoolkit/
   *
   * The FLARToolKit is ActionScript 3.0 version ARToolkit class library.
   * Copyright (C)2008 Saqoosha
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version 2
   * of the License, or (at your option) any later version.
   * 
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   * 
   * You should have received a copy of the GNU General Public License
   * along with this framework; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   * 
   * For further information please contact.
   *        http://www.libspark.org/wiki/saqoosha/FLARToolKit
   *        <saq(at)saqoosha.net>
   * 
   */
  
  package org.libspark.flartoolkit.pv3d {
          
          import org.libspark.flartoolkit.core.FLARMat;
          import org.libspark.flartoolkit.core.param.FLARParam;
          import org.libspark.flartoolkit.core.types.FLARIntSize;
          import org.libspark.flartoolkit.utils.ArrayUtil;
          import org.papervision3d.cameras.Camera3D;
          import org.papervision3d.core.math.Matrix3D;
  
          public class @ax-student-ar-org-libspark-flartoolkit-pv3d-FLARCamera3D extends Camera3D {
                  
                  private static const NEAR_CLIP:Number = 10;
                  private static const FAR_CLIP:Number = 10000;
                  
                  public function @ax-student-ar-org-libspark-flartoolkit-pv3d-FLARCamera3D(param:FLARParam) {
                          super();
                          this.z = 0;
                          
                          var m_projection:Array = new Array(16);
                          var trans_mat:FLARMat = new FLARMat(3,4);
                          var icpara_mat:FLARMat = new FLARMat(3,4);
                          var p:Array = ArrayUtil.createJaggedArray(3, 3);
                          var q:Array = ArrayUtil.createJaggedArray(4, 4);
                          var i:int;
                          var j:int;
                          const size:FLARIntSize = param.getScreenSize();
                          const width:int  = size.w;
                          const height:int = size.h;
                          
                          param.getPerspectiveProjectionMatrix().decompMat(icpara_mat, trans_mat);
                          
                          var icpara:Array = icpara_mat.getArray();
                          var trans:Array = trans_mat.getArray();
                          for (i = 0; i < 4; i++) {
                                  icpara[1][i] = (height - 1) * (icpara[2][i]) - icpara[1][i];
                          }
                          
                          for(i = 0; i < 3; i++) {
                                  for(j = 0; j < 3; j++) {
                                          p[i][j] = icpara[i][j] / icpara[2][2];
                                  }
                          }
                          q[0][0] = (2.0 * p[0][0] / (width - 1));
                          q[0][1] = (2.0 * p[0][1] / (width - 1));
                          q[0][2] = -((2.0 * p[0][2] / (width - 1))  - 1.0);
                          q[0][3] = 0.0;
                          
                          q[1][0] = 0.0;
                          q[1][1] = -(2.0 * p[1][1] / (height - 1));
                          q[1][2] = -((2.0 * p[1][2] / (height - 1)) - 1.0);
                          q[1][3] = 0.0;
                          
                          q[2][0] = 0.0;
                          q[2][1] = 0.0;
                          q[2][2] = -(FAR_CLIP + NEAR_CLIP) / (NEAR_CLIP - FAR_CLIP);
                          q[2][3] = 2.0 * FAR_CLIP * NEAR_CLIP / (NEAR_CLIP - FAR_CLIP);
                          
                          q[3][0] = 0.0;
                          q[3][1] = 0.0;
                          q[3][2] = 1.0;
                          q[3][3] = 0.0;
                          
                          for (i = 0; i < 4; i++) { // Row.
                                  // First 3 columns of the current row.
                                  for (j = 0; j < 3; j++) { // Column.
                                          m_projection[i*4 + j] =
                                                  q[i][0] * trans[0][j] +
                                                  q[i][1] * trans[1][j] +
                                                  q[i][2] * trans[2][j];
                                  }
                                  // Fourth column of the current row.
                                  m_projection[i*4 + 3]=
                                          q[i][0] * trans[0][3] +
                                          q[i][1] * trans[1][3] +
                                          q[i][2] * trans[2][3] +
                                          q[i][3];
                          }
                          
                          this.useProjectionMatrix = true;
                          // 巣の GreatWhite のままだと _projection が Camera3D の private プロパティなのでエラる。
                          // ので protected とかにしてください。無理やり。害はない。つーかまーそれ以外に方法がない。
                          this._projection = new Matrix3D(m_projection);
                  }
                  protected var _projection:*;
                  override public function transformView(transform:Matrix3D=null):void {
                          // Camera3D の transformView はいらんことしやがるので super.transformView() しない。
                          // ただし CameraObject3D の transformView は必要なのでそこでやってる処理をここに移植。
                          this.eye.calculateMultiply(this.transform, _flipY);
                          this.eye.invert(); 
                          this.eye.calculateMultiply4x4(this._projection, this.eye);
                  }
                  
                  // これも Camera3D の private になってるのでここにコピー。Camera3D のんを protected とかに変更でもいいけど。
                  static private var _flipY :Matrix3D = Matrix3D.scaleMatrix( 1, -1, 1 );
          }
          
  }