Similar to google maps zoom/pan, etc. but here the server-side data would be a massive SVG file (converted to SVG from a GDS representing chip layout).
One option I'm considering is taking existing compiled C or Java tools that are native client programs for viewing GDS files and using their source code but redesigning them to split the UI between browser-Ajax and server-side rendering.
IMHO: I feel certain server-side Java, at a low-level can render graphics into a (Swing) Canvas, which becomes raster image to be sent to the client thru AJAX or whatever. But to get a fast solution, I'd still need Java library/package that can render SVG into the Canvas object