Function draw_tiles 

pub fn draw_tiles<U>(
    looks: &Looks<'_>,
    buf: &mut GlyphBuffer,
    scene: &MapScene<U>,
    layout: &Layout,
)

Draws every tile in the plain style (GlyphStyle::draw_tiles): its terrain (tiles off the map are left as they are, blank); a tile whose terrain just changed flashes, its background tinted towards its glyph color, fading out; then its ranges tint it, the first laid on undermost; and a tile that would change is drawn as the terrain it would become instead.