how its done, when you enter to site http://www.calpoly.edu/~mghanson/flash/spacegrid.html pre-loader loading the content of site
and when you re-enter to site you see the
pre-loader once again and pre-loader loading from 1 to 100 fast
what script cause this effect ?
That’s simply how preloaders work, there’s no script that causes it to happen. What basically happens it this: when you first enter the site, the content isn’t in the cache of the user yet. So the content is downloaded, and the preloader displays this progress.
When you reload the site after it has finished loading, the content will already be downloaded to the user’s cache, and therefore the content doesn’t need to be downloaded again. This is why the preloader displays 100 immediately, because the content is already downloaded; it’s already 100% downloaded from the very first second you view the site, because it is in the cache of the user.