/* * Copyright © 2014 Keith Packard * * 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; version 2 of the License. * * 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. */ package org.altusmetrum.altoslib_8; public class AltosRotation { private AltosQuaternion rotation; public double tilt() { double rotz = rotation.z * rotation.z - rotation.y * rotation.y - rotation.x * rotation.x + rotation.r * rotation.r; double tilt = Math.acos(rotz) * 180.0 / Math.PI; return tilt; } public void rotate(double dt, double x, double y, double z) { AltosQuaternion rot = AltosQuaternion.half_euler(x * dt, y * dt, z * dt); rotation = rot.multiply(rotation).normalize(); } /* Clone an existing rotation value */ public AltosRotation (AltosRotation old) { this.rotation = new AltosQuaternion(old.rotation); } /* Create a new rotation value given an acceleration vector pointing down */ public AltosRotation(double x, double y, double z, int pad_orientation) { AltosQuaternion orient = AltosQuaternion.vector(x, y, z).normalize(); double sky = pad_orientation == 0 ? 1 : -1; AltosQuaternion up = new AltosQuaternion(0, 0, 0, sky); rotation = up.vectors_to_rotation(orient); } }