Hi there Brian, I do just this type of stuff all the time. We use this type of "workflow" for web-based decision support tools, with Mapserver on the front end and GRASS on the back end. I can talk to you more about this offline if you want, but the basic idea is to create an "on the fly" GRASS work area in a sessions temp directory and run grass from a scripting language based on user input from Mapserver. I use PHP and have developed a little PHP object structure that emulates the "batch GRASS" type structure to allow for doing raster manipulation via r.mapcalc. All in all it is fast and pretty straight forward once you have done it a couple of times. We have done raster display directly from GRASS, but tend to output to other formats for display in Mapserver for many reasons. Again, there are probably others out there doing similar or other unique things to get the job done, but I am more than happy to talk to you more about how I go about implementing a web-based real time stack via Mapserver and GRASS.
Hope this helps to get you going! Aaron +----------------------------------------+ | Aaron Racicot | [EMAIL PROTECTED] | | GIS Programmer | 503.467.0759 | +----------------------------------------+ | e c o t r u s t | | Jean Vollum Natural Capital Center | | 721 NW Ninth Avenue | | Suite 200 | | Portland, OR 97209 | | www.ecotrust.org | +----------------------------------------+ -----Original Message----- From: UMN MapServer Users List [mailto:[EMAIL PROTECTED] On Behalf Of Fischer, Brian Sent: Monday, December 19, 2005 3:38 PM To: [email protected] Subject: [UMN_MAPSERVER-USERS] Raster Analysis and MapServer MapServer users, I have a project that I would like to generate raster data on the fly and use MapServer to display the results. I am curious if anyone else has tried this. If so what tools did you use to do the raster analysis and how did it work? Let me explain more about the process. 1. Someone would go to a web page and click a button to start the process. 2. Some tool would create raster1 from a line vector file (contours) (need a contour to raster algorithm) 3. Some tool would do a raster calculation (raster1 minus raster2) to produce a final raster 4. MapServer would display the final raster. I need all of this process to happen over the web. I think I can use GRASS to do the raster analysis, but I am curious if anyone else has done this sort of thing. My other option is to go to ESRI's ArcGISServer (which I don't want to do, if I don't have to). Are there any other tools available to do raster analysis (spatial analysis) on the web? Any insight would be helpful. Thanks, Brian Brian Fischer, GIS Specialist/Programmer Houston Engineering, Inc. | Leave Nothing to ChanceTM 10900 73rd AVE N, Suite 106 Maple Grove, MN 55369 Phone: 763.493.4522 / Fax: 763.493.5572 Email: [EMAIL PROTECTED] Website: www.houstonengineeringinc.com
