Hey Ahuimanu,In order to do vector plots of Lat/Long type data, you basically need a projection system to convert from Lat/Long into pixels based on various other map view parameters (things like center location, zoom level, etc). There are a whole bunch of different ways to do map projections (do a google search on map projections and I bet you find a bunch :->).There are probably some freeware/shareware modules out there that will do this sort of thing, but I don't know of any off the top of my head (check out http://www.gotdotnet.com and/or http://www.codeproject.com as a couple of good starting points to search for modules that might relate to what you want to do).I've done some similar type stuff in C#/.Net/GDI+ to display data from the US Census TigerLINE dataset, and most of my performance problems have to do with handling the database itself, swapping new stuff into memory as the map location moves and dumping the old stuff, the drawing code seems to be fast enough :->.Tim

Hi Beatle,Well, I understand projections in terms of Lambert Conformal, Mercator, etc. but I think you are suggesting that I perhaps make my own? I suppose you mean that I have to determine what area a pixel represents. I'll explore the repositories you suggest. There is also http://www.sharpgis.net, but I suppose I was after trying to learn the concepts myself.Thanks for the feedback... :-)

>>> Can you point me in the right direction? I know that there are method calls to do all of this in System.Drawing, but I am not sure how to use them correctly...Hey there... I will try to get back to you on this (been caught up at work this week). I do not use the built in transforms anymore because they produce some unwanted side effects for maps. However, it is still important to understand 2D Transformation theory and matrix algebra. This is the critical math of map rendering. Here is a good starting point:http://www.willamette.edu/~gorr/classes/Ge...ransforms2d.htmAlso Google "2D Transformations".The transforms should make more sense after reading about this stuff.

thanks...reading.