caching tile images in isolated storage

Jul 4, 2008 at 1:03 AM
We are diving deep into this Deep Earth SL map, Thank you Guys for the wonderful start.
Question :
We are trying to cache the tiles [along with pins] in the iso store, so re-visit is instant. As i see VETileSource always
uses url and the MultiScaleImage.Source needs a Url.

Is there a way i can use local iso store as url for this MSI ?


Jul 5, 2008 at 12:14 AM
Interesting idea, I'd love to hear what you find out about this.
The tiles themselves in the case of VE are only allowed to cached for 7 days and this is typically done by your normal browser cache since the header on the tiles have all ready been set.

So Question 1, Are the tiles when used in Silverlight being cached by the browser already?
Q2, On subsequent requests are the tiles being served from this cache as expected?

My understanding is the local isolated storage for a silverlight app is pretty small, 100KB, but you can prompt the user to allow the app to use more space.
I always thought this as a great place to store user preferences, perfect place to store their last view so when they return to the map it is where they left off. So for example if they refresh the page its like they never left. I'm ging to add a work item for this now. Note, it seems many people are using the JSON serialisation for objects to keep the size down when storing locally.

Back to storing the tiles, there is potentially so much data here, are you looking for a way to store the inital view so for faster loading times? or you looking for some option to allow for a dissconnected experience?

Jul 6, 2008 at 2:26 AM
1. I'm pre-setting browser header cache to no-cache! because any new changes in .xap file is not reflecting on client browser [on refresh, though i can see the .xap is gettting downloaded], i have to clear internet browser cache manually and then re-fresh browser to get new changes [Just on Push pins only, other non-pushpin controls works fine on refresh!]

2. FYI: In Beta 2 default ISO size is 1 MB [and max, i guess limited to hard disk space available?] , that is reason we started experimenting ISO Store.

3. For out App, each push pin is a info box with atleast 20 work items, which takes lots of time to calculate, but hardly changes. If user closes the browser at German level, we need to store
all Push pins information on ISO and when user comes back just display last used.

All the above points just explains my situation, now coming back to my original requirements, i'm not looking for VE map tile caching, the German level map can be loaded each time, but inside our info box we have MultiScaleImages(!) which is loaded using url. When user quits at a level we store all info [including images] in ISO.

Here's where i need some help to figure how to load back the image [from ISO] to the MultiScaleImage inside the push pins.

Hope i made myself clear!