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    <blockquote> <p>At any given time, Given the original real part, the original imaginary part, and the max number of iterations, I'd like to be able to get a result set with the final real and imaginary parts.</p> </blockquote> <p>It is not clear from your question why you need this? Why do you need to re-compute at the same point?</p> <p>In case you are experimenting with different max_iterations settings, you can just save the actual_iterations taken at a per-pixel level in a binary-file, text-file or image or whatever you find convenient to load/store, e.g. a relational database.</p> <p>If you are doing real-time rendering and you are using some processing which requires re-calculating the recurrence equation (at the same original point and with the same max iterations), then I would imagine you could speed this up by having a look-up table.</p> <p>Obviously, your look-up table must be faster than doing the computation. You need a look-up table for which the below operations in total take less than doing the computation again.</p> <ul> <li>calculate index (given origo_real,origo_imag,max_iter) </li> <li>load the cached computation (final_real, final_imag, actual_iter) </li> <li>one initial store</li> </ul> <p>Depending on how you will re-compute / re-access at the same points, you could divide your problem in such a way that it is highly likely that the index is in the look-up table and the look-up table is small enough to be stored in a L1 or L2 cache. </p> <p>Those are some ideas.. but you should clarify what your real problem is.</p> <p>In case you just need a lot of this data for further analysis and real-time is not the requirement, then well... clarify what your real issue is :)</p> <p><strong>answer for the update</strong></p> <p>It seems similar to using a map service (zoom in/out, move around), that is, you are essentially delivering an image for a given area and zoom.</p> <p>However in this case, since any zoom-level may be queried, whatever you cache for one user, may not be re-used for the next user. I am not sure why it would make sense to do it this way rather than writing a client software in which the user can zoom real-time (which has been done).</p> <p>In any case. If your main problem is bandwidth but you have plenty of computation power, then you could store images of a calculated patch in a highly compressed file, with a bit lower quality and cache these images. You may then need to stitch patches of these together to deliver the exact area the user wanted.. the trick would be to query the minimal set of patches given the zoom and area. </p> <p>I fear that most queries would be asking for patches which does not exist (since any zoom-level is possible). Perhaps some info on how e.g. Google Maps / GIS systems work could give you some ideas. If your main problem is CPU, then maybe you could do this differently and let the user do the computation in an Applet (and possibly send back the result) </p> <p>If you are doing this to learn how to cache/compute over client-server, you might want to consider a different challenge, as this one can be solved on client side by any decent computer.</p>
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    1. POWhat might be the best method of storing Mandelbrot values in a database?
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    1. POWhat might be the best method of storing Mandelbrot values in a database?
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    1. COThanks for the answer, julienaubert! I've added a huge new chunk of information that will (hopefully) let you conceptualize a bit better what I'm trying to achieve. I'll keep writing until my words run off to infinity (so to speak) if it helps you!
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    2. CO@julienaubert Thanks again, julienaubert. I suppose you're right about the impracticality of this initial plan. I suppose what I really plan to do is to allow users run through pre-rendered zooms only to give people a good idea of what the canvas element can do in terms of rendering. I'll possibly also do this through a persistent Web Sockets connection for maximum transfer rates. I've already given you the points for this answer, but if you have any more thoughts, I'd love to hear them. Thanks again!
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    3. COwhy don't you let them paint in the canvas, and collaborate :)
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