//------------------------------------------------------------------------
//  EPI Bounding Boxes
//------------------------------------------------------------------------
// 
//  Copyright (c) 2003-2005  The EDGE Team.
// 
//  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.
//
//------------------------------------------------------------------------

#include "math_bbox.h"

#include <math.h>

namespace epi
{

int bbox3_c::IntersectPlane(vec3_c loc, vec3_c face) const
{
	// determine the two points of the bounding box that are
	// nearest and furthest away from the plane (via the plane's
	// normal).  We only need to test these two points.

	vec3_c L(face.x < 0 ? hi.x : lo.x,
	         face.y < 0 ? hi.y : lo.y,
	         face.z < 0 ? hi.z : lo.z);

	vec3_c H(face.x < 0 ? lo.x : hi.x,
	         face.y < 0 ? lo.y : hi.y,
	         face.z < 0 ? lo.z : hi.z);

	// check the distances
	float L_dist = (L - loc) * face;

	if (L_dist >= 0)
		return HIT_INSIDE;

	float H_dist = (H - loc) * face;

	if (H_dist <= 0)
		return HIT_OUTSIDE;

	return HIT_PARTIAL;
}

}