// Stock By: DarkGL | http://forums.alliedmods.net/showthread.php?t=176424
 
#include <amxmodx>
#include <amxmisc>
#include <fakemeta>
#include <xs>
 
#define PLUGIN	"Granat Trail"
#define AUTHOR	"DarkGL"
#define VERSION	"1.0"
 
new laser;
 
public plugin_init()
{
	register_plugin(PLUGIN, VERSION, AUTHOR)
}
 
public plugin_precache(){
			laser   =       precache_model("sprites/laserbeam.spr")
}
 
public client_PreThink( id ){
        if( is_user_alive( id ) ){
                new iWeapon     =       get_user_weapon( id );
 
                if( iWeapon == CSW_HEGRENADE || iWeapon == CSW_SMOKEGRENADE || iWeapon == CSW_FLASHBANG){
                        showGrenadeWay( id , iWeapon );
                }
        }
}
 
stock showGrenadeWay ( id , weapon ){
    new Float:fGrenadeGrav = 1.0;
 
    switch( weapon) {
    case CSW_HEGRENADE:
        fGrenadeGrav    =                 0.55;
    case CSW_FLASHBANG:
        fGrenadeGrav    =                 0.5;
    case CSW_SMOKEGRENADE:
        fGrenadeGrav    =                 0.5;
    }
    static pGrav;
 
    if( !pGrav )    pGrav   =          get_cvar_pointer( "sv_gravity" );
 
    new Float:fStartPos[ 3 ] , Float: fViewOfs[ 3 ] , Float: fVector[ 3 ] , Float: fVeloc [ 3 ] , Float: fAngles [ 3 ] , Float: fEndPos [ 3 ] , Float: fTmpVector [ 3 ] , pTr , Float: fFraction , Float: fNormal [ 3 ] , iCollision = 0 , Float: fVel;
    new Float:fGrav =                 get_pcvar_float( pGrav ) , pHit = 0;
 
    const            maxCollsion                =            30;
    const Float:    fConstAliveTime            =            2.0;
    const Float:    fConstLoops                =            20.0;
    new Float:        fAliveTime                =            0.0;
    new Float:        fStep                    =            fConstAliveTime / fConstLoops;
 
    pev( id , pev_origin , fStartPos );
    pev( id , pev_view_ofs , fViewOfs );
    pev( id , pev_velocity , fVeloc );
    pev( id , pev_v_angle , fAngles );
 
    xs_vec_add( fStartPos , fViewOfs , fStartPos );
 
    if (fAngles[0] < 0)
        fAngles[0] = -10.0 + fAngles[0] * ((90.0 - 10.0) / 90.0);
    else
        fAngles[0] = -10.0 + fAngles[0] * ((90.0 + 10.0) / 90.0);
 
    fVel = (90.0 - fAngles[0]) * 6.0;
    if (fVel > 750.0)
        fVel = 750.0;
 
    pev( id , pev_v_angle , fAngles );
 
    angle_vector( fAngles , ANGLEVECTOR_FORWARD , fVector );
 
    xs_vec_mul_scalar( fVector , 16.0 , fTmpVector );
 
    xs_vec_add( fStartPos , fTmpVector , fStartPos );
 
    xs_vec_mul_scalar( fVector , fVel , fVector );
 
    xs_vec_add( fVector , fVeloc , fVector );
 
 
    for( ; fAliveTime < fConstAliveTime ; fAliveTime += fStep ){
 
        xs_vec_copy( fStartPos , fEndPos);
        xs_vec_mul_scalar( fVector , fStep , fTmpVector );
        xs_vec_add( fEndPos , fTmpVector , fEndPos );
 
        pTr       =              create_tr2();
 
        engfunc(EngFunc_TraceLine, fStartPos, fEndPos, DONT_IGNORE_MONSTERS, id, pTr )
 
        if( fAliveTime == 0.0 ){
            fStartPos [ 2 ] += 10.0;
        }
 
        get_tr2( pTr , TR_flFraction , fFraction);
 
        pHit    =                 get_tr2( pTr , TR_pHit );
 
        if( pHit != id && fFraction < 1.0 ){
            get_tr2( pTr , TR_vecEndPos , fEndPos );
 
            get_tr2( pTr , TR_vecPlaneNormal , fNormal )
 
            if( fNormal [ 2 ] > 0.9 && fVector [ 2 ] <= 0.0 && fVector [ 2 ] >= -fGrav / 0.20 ){
                return ;
            }
 
            new Float: fScalar = xs_vec_dot( fVector, fNormal ) * 1.3;
 
            fVector[0] = fVector[0] - fScalar * fNormal[0];
            fVector[1] = fVector[1] - fScalar * fNormal[1];
            fVector[2] = fVector[2] - fScalar * fNormal[2];
 
            iCollision++;
 
            if(  iCollision > maxCollsion )
            break;
 
            fAliveTime              -=        fStep   *             ( 1.0 - fFraction ) ;
        }
 
        new iR , iG , iB;
 
        switch( weapon ) {
        case CSW_HEGRENADE:{
                iR = 250;
                iG = 0;
                iB = 0;
            }
        case CSW_FLASHBANG:{
                iR = 0;
                iG = 0;
                iB = 250;
            }
        case CSW_SMOKEGRENADE:{
                iR = 0;
                iG = 250;
                iB = 0;
            }
        }
 
        message_begin( MSG_ONE_UNRELIABLE , SVC_TEMPENTITY , { 0 , 0 , 0 } , id )
        write_byte(0)
        engfunc( EngFunc_WriteCoord , fStartPos [ 0 ] )
        engfunc( EngFunc_WriteCoord , fStartPos [ 1 ] )
        engfunc( EngFunc_WriteCoord , fStartPos [ 2 ] )
        engfunc( EngFunc_WriteCoord , fEndPos [ 0 ] )
        engfunc( EngFunc_WriteCoord , fEndPos [ 1 ] )
        engfunc( EngFunc_WriteCoord , fEndPos [ 2 ] )
        write_short(laser)
        write_byte(1)
        write_byte(1)
        write_byte(1)
        write_byte(15)
        write_byte(0)
        write_byte( iR )
        write_byte( iG )
        write_byte( iB )
        write_byte(210)
        write_byte(0)
        message_end()
 
        xs_vec_copy( fEndPos , fStartPos );
 
        fVector[ 2 ]    -=              floatmul( floatmul( fGrenadeGrav , fGrav ) , floatmul( fFraction , fStep ) );
 
        free_tr2( pTr );
    }
}