function jzMakeAdvancedTerrain(mediadir as string, heightmap as string, ...
                               texture as string, detail as string, ...
                               skybox as string)
    savedir as string
    skyboxobj as integer

    if mediadir <> NULLSTR
        savedir = get dir$()
        cd mediadir
    else
       savedir = NULLSTR
    endif
    if image exist(1) = 1 then delete image 1
    if image exist(2) = 1 then delete image 2
    load image texture, 1
    load image detail, 2
    make object terrain 1
    set terrain heightmap 1, heightmap
    set terrain scale 1, 4, 0.5, 4
    set terrain tiling 1, 4
    set terrain split 1, 8
    set terrain light 1, 0.0, -64.0, 0.0, 1.0, 0.75, 0.75, 0.5
    set terrain texture 1, 1, 2
    build terrain 1
    skyboxobj = jzGetNextAvailableObjectID(1)
    load object skybox, skyboxobj
    set object light skyboxobj, 0
    set object texture skyboxobj, 1, 1
    position object skyboxobj, 0, 0, 0
    scale object skyboxobj, 5000, 5000, 5000
    if savedir <> NULLSTR
        cd savedir
    endif
endfunction