no. 25 - Is player entity aiming in rect

/*
-----------------------------------------
* Game hacking QTS ( Quickie Tip Series )
* no. 25 - Is player entity aiming in rect
-----------------------------------------
* Author: SEGnosis  - GHAnon.net
* Thanks to:
* bitterbanana      - No known site
* Drunken Cheetah   - No known site
* fatboy88      - No known site
* Geek4Ever         - No known site
* learn_more        - www.uc-forum.com
* Novocaine         - http://ilsken.net/blog/?page_id=64
* Philly0494        - No known site
* Roverturbo        - www.uc-forum.com
* SilentKarma       - www.halocoders.com - offline
* Strife        - www.uc-forum.com
* Wieter20      - No known site
*/

bool C_Entity_Manager::IsPlayerEntityAimingInRect( C_Player_Entity* pEntity, FVect3 vA, float fWidth )
{
    FTrigFunc vTrig;

    vTrig.cosine    = cosf( pEntity->m_vView.yaw );
    vTrig.sine  = sinf( pEntity->m_vView.yaw );

    FVect3 vDistance;

    vA.y -= PMH_CROUCH;

    PointDifference( pEntity->m_vPos, vA, vDistance );

    double fDistance = PointProduct( vDistance );
    float fHeight = fWidth * 2.5f;

    FVect3 vPoint = { pEntity->m_vPos.x + ( vTrig.sine * fDistance ), pEntity->m_vPos.y + ( -pEntity->m_vView.pitch * fDistance ), pEntity->m_vPos.z + ( vTrig.cosine * fDistance ) };

    if( vPoint.x >= vA.x-fWidth && vPoint.x <= vA.x+fWidth &&
        vPoint.z >= vA.z-fWidth && vPoint.z <= vA.z+fWidth &&
        vPoint.y >= vA.y        && vPoint.y <= vA.y+fHeight )
        return true;

    return false;
}