/**
 * @(#) $RCSfile: MouseEngineLoopStrip.as,v $ $Revision: 1.1 $ $Date: 2003/02/13 21:23:47 $
 *
 * Copyright 2003 Orgdot AS. All Rights Reserved.
 * http://dev.swfit.com
 *
 * 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 program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

/**
 * Generates several mouse xy values with delays and bounce. See MouseEngineInit
 * for further information.
 *
 * @author      Olaf Havnes
 * @version     $Revision: 1.1 $ $Date: 2003/02/13 21:23:47 $
 * @since       SWFIT1.0
 */

/**
 * Get the mouse x position.
 */
// The real mouse x position
old_x = x;
x = _x;

// The clipped mouse x position
if (x < /:x_min) cl_x = /:x_min;
else if (x > /:x_max) cl_x = /:x_max;
else cl_x = x;

// The delayed mouse x position
dc_x = (dc_x * /:delay + cl_x) / (/:delay + 1);

/**
 * Repeat for y.
 */
// The real mouse y position
old_y = y;
y = _y;

// The clipped mouse y position
if (y < /:y_min) cl_y = /:y_min;
else if (y > /:y_max) cl_y = /:y_max;
else cl_y = y;

// The delayed mouse y position
dc_y = (dc_y * /:delay + cl_y) / (/:delay + 1);


/**
 * The camera model uses the delayed-clipped mouse values, producing values between 
 * - 1 and 1 for camera-position, reversing the sign for the y-values (+ is now up).
 */
cam_x =   dc_x / /:cw_2 + /:xwa;
cam_y = - dc_y / /:ch_2 + /:ywa;

// Pre-compute
cam_x2 = cam_x * cam_x;
cam_y2 = cam_y * cam_y;
cam_z2 = cam_len_sq - cam_x2 - cam_y2;

// Iterate just once through Newton's method. I doubt anybody is able to move the
// mouse quick enough to produce a significant error on this value, especially since 
// the camera uses the delayed mouse values.
cam_z = (cam_z + cam_z2 / cam_z) / 2;

// Store in _level0.
/:camera_x = cam_x;
/:camera_y = cam_y;
/:camera_z = cam_z;