Re: How can I efficiently store GPS vectors for graphical map?
- Posted by Spock May 13, 2011
- 1843 views
Hi, you need an optimized algorithm that will present on the screen vector drawing ... you manage to present it? Viewing the code to optimize it could look ...
Hi Javier,
Thanks for replying. I am now approaching the completion of the project. The optimization I need relates to how to efficiently store the vectors at a higher level. The line drawing part is close to as fast as it will be (I´m using Bbresenham´s integer line drawing routine algo writing directly to a Dibsection in RAM) but a compiled version should just fly along. Eventually (soon), I´ll post the code, For now I was hoping for ideas about how to store each vector (GPS) string. I sort the vectors in descending order of longitude to improve locality (ie, the vector culling inevitably required is able to focus on a subset of the entire database, improving performance) but even so there is a lot of culling required - these are the roads for an entire country, admittedly not a very big country by world standards, still...
kind regards, Spock
I´ve changed my mind on this about releasing the source since the code is not fully compatible with 4.0. Besides, there´s not likely to be much demand for a custom road map of NZ in this forum. However, if anyone is genuinely interested they can contact me directly (vulcan AT_SYMBOL win POINT co PERIOD nz) to discuss the idea.
Spock
