warzone2100/lib/ivis_opengl/piematrix.h

/*
	This file is part of Warzone 2100.
	Copyright (C) 1999-2004  Eidos Interactive
	Copyright (C) 2005-2007  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
*/
/***************************************************************************/
/*
 * pieMatrix.h
 *
 * matrix functions for pumpkin image library.
 *
 */
/***************************************************************************/
#ifndef _pieMatrix_h
#define _pieMatrix_h

#include "lib/ivis_common/piedef.h"

/***************************************************************************/
/*
 *	Global Variables
 */
/***************************************************************************/

extern SDWORD aSinTable[];

//*************************************************************************

// FIXME DUPLICATE CODE! Already present in trig.c!
#define SIN(X) aSinTable[(Uint16)(X) >> 4]
#define COS(X) aSinTable[((Uint16)(X) >> 4) + 1024]


//*************************************************************************

/*!
 * Rotate and translate v with the worldmatrix. Store the result in s
 * \param[in] v Vector to translate
 * \param[out] s Resulting vector
 */
void pie_RotateTranslate3iv(const Vector3i *v, Vector3i *s);


/*!
 * Calculate surface normal
 * Eg. if a polygon (with n points in clockwise order) normal is required,
 * \c p1 = point 0, \c p2 = point 1, \c p3 = point n-1
 * \param p1,p2,p3 Points for forming 2 vector for cross product
 * \return Normal vector
 */
static inline WZ_DECL_CONST WZ_DECL_WARN_UNUSED_RESULT
		Vector3f pie_SurfaceNormal3fv(const Vector3f p1, const Vector3f p2, const Vector3f p3)
{
	Vector3f
		a = {
			p3.x - p1.x,
			p3.y - p1.y,
			p3.z - p1.z
		},
 		b = {
			p2.x - p1.x,
			p2.y - p1.y,
			p2.z - p1.z
		};

	a = Vector3f_Normalise(a);
	b = Vector3f_Normalise(b);

	{ // MSVC hack
		Vector3f
			v = {
				(a.y * b.z) - (a.z * b.y),
				(a.z * b.x) - (a.x * b.z),
				(a.x * b.y) - (a.y * b.x)
			};

		return Vector3f_Normalise(v);
	}
}

//*************************************************************************


extern void pie_MatInit(void);


//*************************************************************************

extern void pie_MatBegin(void);
extern void pie_MatEnd(void);
extern void pie_MATTRANS(int x, int y, int z);
extern void pie_TRANSLATE(int x, int y, int z);
extern void pie_MatScale( UDWORD percent );
extern void pie_MatRotX(int x);
extern void pie_MatRotY(int y);
extern void pie_MatRotZ(int z);
extern Sint32 pie_RotateProject(const Vector3i *src, Vector2i *dest);

//*************************************************************************

extern void pie_PerspectiveBegin(void);
extern void pie_PerspectiveEnd(void);

extern void pie_TranslateTextureBegin(Vector2f offset);
extern void pie_TranslateTextureEnd(void);

//*************************************************************************

extern void pie_VectorInverseRotate0(const Vector3i *v1, Vector3i *v2);
extern void pie_SetGeometricOffset(int x, int y);

extern void pie_Begin3DScene(void);
extern void pie_BeginInterface(void);

#endif