/**
 * @file llbbox.cpp
 * @brief General purpose bounding box class (Not axis aligned)
 *
 * $LicenseInfo:firstyear=2001&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#include "linden_common.h"

// self include
#include "llbbox.h"

// library includes
#include "m4math.h"

void LLBBox::addPointLocal(const LLVector3& p)
{
    if (mEmpty)
    {
        mMinLocal = p;
        mMaxLocal = p;
        mEmpty = false;
    }
    else
    {
        mMinLocal.mV[VX] = llmin( p.mV[VX], mMinLocal.mV[VX] );
        mMinLocal.mV[VY] = llmin( p.mV[VY], mMinLocal.mV[VY] );
        mMinLocal.mV[VZ] = llmin( p.mV[VZ], mMinLocal.mV[VZ] );
        mMaxLocal.mV[VX] = llmax( p.mV[VX], mMaxLocal.mV[VX] );
        mMaxLocal.mV[VY] = llmax( p.mV[VY], mMaxLocal.mV[VY] );
        mMaxLocal.mV[VZ] = llmax( p.mV[VZ], mMaxLocal.mV[VZ] );
    }
}

void LLBBox::addPointAgent( LLVector3 p)
{
    p -= mPosAgent;
    p.rotVec( ~mRotation );
    addPointLocal( p );
}


void LLBBox::addBBoxAgent(const LLBBox& b)
{
    if (mEmpty)
    {
        mPosAgent = b.mPosAgent;
        mRotation = b.mRotation;
        mMinLocal.clearVec();
        mMaxLocal.clearVec();
    }
    LLVector3 vertex[8];
    vertex[0].setVec( b.mMinLocal.mV[VX], b.mMinLocal.mV[VY], b.mMinLocal.mV[VZ] );
    vertex[1].setVec( b.mMinLocal.mV[VX], b.mMinLocal.mV[VY], b.mMaxLocal.mV[VZ] );
    vertex[2].setVec( b.mMinLocal.mV[VX], b.mMaxLocal.mV[VY], b.mMinLocal.mV[VZ] );
    vertex[3].setVec( b.mMinLocal.mV[VX], b.mMaxLocal.mV[VY], b.mMaxLocal.mV[VZ] );
    vertex[4].setVec( b.mMaxLocal.mV[VX], b.mMinLocal.mV[VY], b.mMinLocal.mV[VZ] );
    vertex[5].setVec( b.mMaxLocal.mV[VX], b.mMinLocal.mV[VY], b.mMaxLocal.mV[VZ] );
    vertex[6].setVec( b.mMaxLocal.mV[VX], b.mMaxLocal.mV[VY], b.mMinLocal.mV[VZ] );
    vertex[7].setVec( b.mMaxLocal.mV[VX], b.mMaxLocal.mV[VY], b.mMaxLocal.mV[VZ] );

    LLMatrix4 m( b.mRotation );
    m.translate( b.mPosAgent );
    m.translate( -mPosAgent );
    m.rotate( ~mRotation );

    for( S32 i=0; i<8; i++ )
    {
        addPointLocal( vertex[i] * m );
    }
}

LLBBox LLBBox::getAxisAligned() const
{
    // no rotation = axis aligned rotation
    LLBBox aligned(mPosAgent, LLQuaternion(), LLVector3(), LLVector3());

    // add the center point so that it's not empty
    aligned.addPointAgent(mPosAgent);

    // add our BBox
    aligned.addBBoxAgent(*this);

    return aligned;
}

void LLBBox::expand( F32 delta )
{
    mMinLocal.mV[VX] -= delta;
    mMinLocal.mV[VY] -= delta;
    mMinLocal.mV[VZ] -= delta;
    mMaxLocal.mV[VX] += delta;
    mMaxLocal.mV[VY] += delta;
    mMaxLocal.mV[VZ] += delta;
}

LLVector3 LLBBox::localToAgent(const LLVector3& v) const
{
    LLMatrix4 m( mRotation );
    m.translate( mPosAgent );
    return v * m;
}

LLVector3 LLBBox::agentToLocal(const LLVector3& v) const
{
    LLMatrix4 m;
    m.translate( -mPosAgent );
    m.rotate( ~mRotation );  // inverse rotation
    return v * m;
}

LLVector3 LLBBox::localToAgentBasis(const LLVector3& v) const
{
    LLMatrix4 m( mRotation );
    return v * m;
}

LLVector3 LLBBox::agentToLocalBasis(const LLVector3& v) const
{
    LLMatrix4 m( ~mRotation );  // inverse rotation
    return v * m;
}

bool LLBBox::containsPointLocal(const LLVector3& p) const
{
    if (  (p.mV[VX] < mMinLocal.mV[VX])
        ||(p.mV[VX] > mMaxLocal.mV[VX])
        ||(p.mV[VY] < mMinLocal.mV[VY])
        ||(p.mV[VY] > mMaxLocal.mV[VY])
        ||(p.mV[VZ] < mMinLocal.mV[VZ])
        ||(p.mV[VZ] > mMaxLocal.mV[VZ]))
    {
        return false;
    }
    return true;
}

bool LLBBox::containsPointAgent(const LLVector3& p) const
{
    LLVector3 point_local = agentToLocal(p);
    return containsPointLocal(point_local);
}

LLVector3 LLBBox::getMinAgent() const
{
    return localToAgent(mMinLocal);
}

LLVector3 LLBBox::getMaxAgent() const
{
    return localToAgent(mMaxLocal);
}

/*
LLBBox operator*(const LLBBox &a, const LLMatrix4 &b)
{
    return LLBBox( a.mMin * b, a.mMax * b );
}
*/