Improve The Third Person View with Zoom

Add this code to GAME.CON, after include USER.CON.

gamevar cameraonwall 0 1
gamevar camzoomcontrol 65536 1

onevent EVENT_LOOKUP
    setvar RETURN -1
    addvar camzoomcontrol -8192 // cam zoom in speed
    ifvarl camzoomcontrol 0
        setvar camzoomcontrol 0 // cam max zoom in
endevent

onevent EVENT_LOOKDOWN
    setvar RETURN -1
    addvar camzoomcontrol 8192 // cam zoom out speed
    ifvarg camzoomcontrol 1048576
        setvar camzoomcontrol 1048576 // cam max zoom out
endevent

onevent EVENT_DISPLAYROOMS
    setvar cameradist 0
    updatesectorz camerax cameray cameraz cameraonwall
    ifvarn cameraonwall -1
        addvarvar cameradist camzoomcontrol
    else
    {
        addvar camzoomcontrol -8192
        addvarvar cameradist camzoomcontrol
    }
endevent