+// $Id$
+//
+// SuperTux
+// Copyright (C) 2004 Tobias Glaesser <tobi.web@gmx.de>
//
-// C++ Interface: physic
-//
-// Description:
-//
-//
-// Author: Tobias Glaesser <tobi.web@gmx.de>, (C) 2004
-//
-// Copyright: See COPYING file that comes with this distribution
-//
+// 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.
#ifndef SUPERTUX_PHYSIC_H
#define SUPERTUX_PHYSIC_H
-#include "timer.h"
+/** This is a very simplistic physics engine handling accelerated and constant
+ * movement along with gravity.
+ */
+class Physic
+{
+public:
+ Physic();
+ ~Physic();
-enum {
- PH_VT, /* Vertical throw.*/
-};
+ /** resets all velocities and accelerations to 0 */
+ void reset();
+
+ /** sets velocity to a fixed value */
+ void set_velocity(float vx, float vy);
+
+ void set_velocity_x(float vx);
+ void set_velocity_y(float vy);
-/* Physic type: */
-
-typedef struct physic_type
- {
- int state;
- float start_vy;
- unsigned int start_time;
- }
-physic_type;
-
-void physic_init(physic_type* pphysic);
-int physic_get_state(physic_type* pphysic);
-void physic_set_state(physic_type* pphysic, int nstate);
-void physic_set_start_vy(physic_type* pphysic, float start_vy);
-float physic_get_velocity(physic_type* pphysic);
-float physic_get_max_distance(physic_type* pphysic);
-unsigned int physic_get_max_time(physic_type* pphysic);
-unsigned int physic_get_time_gone(physic_type* pphysic);
+ /** velocities invertion */
+ void inverse_velocity_x();
+ void inverse_velocity_y();
+
+ float get_velocity_x();
+ float get_velocity_y();
+
+ /** sets acceleration applied to the object. (Note that gravity is
+ * eventually added to the vertical acceleration)
+ */
+ void set_acceleration(float ax, float ay);
+
+ void set_acceleration_x(float ax);
+ void set_acceleration_y(float ay);
+
+ float get_acceleration_x();
+ float get_acceleration_y();
+
+ /** enables or disables handling of gravity */
+ void enable_gravity(bool gravity_enabled);
+
+ /** applies the physical simulation to given x and y coordinates */
+ void apply(float frame_ratio, float &x, float &y);
+
+ /** applies the physical simulation to given x and y coordinates */
+ void apply(Vector& vector, float frame_ratio);
+
+private:
+ /// horizontal and vertical acceleration
+ float ax, ay;
+ /// horizontal and vertical velocity
+ float vx, vy;
+ /// should we respect gravity in out calculations?
+ bool gravity_enabled;
+};
#endif /*SUPERTUX_PHYSIC_H*/