AJAX - The Complete Reference

398 Part II: Developing an Ajax Library^

NNOT EOTE If you really want to make this pattern work well, a sophisticated implementation would

likely increase or decrease the fetch size based upon scroll velocity and the user’s connection rate.

A final idea of progressive loading is a zoomable image (http://ajaxref.com/ch8/

zoomify.html). Such ideas look quite complex, but they really are quite simple. The user is

presented a base image and, as they click it, a new image of the same dimensions is fetched

but in a higher resolution that is centered upon where they clicked. Depending on how high

FIGURE 8-17 Scroll to fetch data