warzone2100/lib/framework/trig.h

/*
	This file is part of Warzone 2100.
	Copyright (C) 1999-2004  Eidos Interactive
	Copyright (C) 2005-2009  Warzone Resurrection Project

	Warzone 2100 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.

	Warzone 2100 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 Warzone 2100; if not, write to the Free Software
	Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/** 
 * @file
 *
 * Interface to trig lookup tables.
 */

#ifndef _trig_h
#define _trig_h

#include "frame.h"
#include "math_ext.h"

#ifdef __cplusplus
extern "C"
{
#endif //__cplusplus

/* The number of units around a full circle */
#define TRIG_DEGREES	360

/* Initialise the Trig tables */
extern BOOL trigInitialise(void);

/* Shutdown the trig tables */
extern void trigShutDown(void);

/* Lookup trig functions */
// These can be assumed const, since they only rely on memory setup on startup
extern float trigSin(int angle) WZ_DECL_CONST;
extern float trigCos(int angle) WZ_DECL_CONST;
extern float trigInvSin(float val) WZ_DECL_CONST;
extern float trigInvCos(float val) WZ_DECL_CONST;

/* Supposedly fast lookup sqrt - unfortunately it's probably slower than the FPU sqrt :-( */
extern float trigIntSqrt(unsigned int val);

#ifdef __cplusplus
}
#endif //__cplusplus

#endif