Re: [UMN_MAPSERVER-USERS] Mapscript Re-Projection on-the-fly

[Stefan Schwarzer]

Jacob & Nicol, thanks for your feedback. But I am still struggling. Just to clarify: I wonna reproject not individual layers, but my whole map. Jacob, does "For this, it is required that your layer has a projection object with the native projection of that layer." that mean that for each single layer I have to specify the original projection? (Geographic in my case) As Nicol stated I need to "recalculate" the extent, at least when using different units (going from DD to Meters).  But then, I found that piece of code (slightly changed): $newproj=ms_newprojectionObj("proj=robin,lon_0=0,x_0=0,y_0=0"); $latlon=ms_newprojectionObj("proj=longlat,ellps=WGS84,datum=WGS84,no_defs"); $oldext=ms_newRectObj(); $oldext->setextent(-180,-90,180,90);  //this is the extent of my map in geographic $oldext->project($latlon,$newproj);  //reproject to Robinson $map->setextent($oldext->minx,$oldext->miny,$oldext->maxx,$oldext->maxy);  //set the new map extent And another one going like this: $projInObj = ms_newProjectionObj( "+proj=tmerc ".   "+lat_0=49 ".   "+lon_0=-2 ".   "+k=0.999601 ".   "+x_0=400000 ".   "+y_0=-100000 ".   "+ellps=airy ".   "+towgs84=375,-111,431,0,0,0,0"); with this info in the mapscript documentation...  int setProjection(string proj_params, boolean bSetUnitsAndExtents)         Set map projection and coordinate system.  Parameters are given as          a single string of comma-delimited PROJ.4 parameters.         The argument : bSetUnitsAndExtents is used to automatically update         the map units and extents based on the new projection. Possible          values are MS_TRUE and MS_FALSE. By defualt it is set at MS_FALSE So, what should I use? And where is coming the  $map -> setProjection into play? Thanks for any clarification. Stefan On Aug 24, 2006, at 7:59 AM, Delfos, Jacob wrote: Stefan,   Your question is not entirely clear. You can not re-project an individual layer on-the-fly, because php_mapscript does not re-write the dataset (hence its projection will always be the same); you CAN however change the projection of the map (using setProjection, as you did), which means all layers in the map get re-projected (the dataset remains unchanged, though). For this, it is required that your layer has a projection object with the native projection of that layer. This will cause the layer to be reprojected along with the map. Is this what you are trying to do?    You *may* have to save your mapfile, or your session, in order for it to take effect, depending on your setup.   regards,   Jacob   From: UMN MapServer Users List [mailto:MAPSERVER-USERS@LISTS.UMN.EDU] On Behalf Of Stefan Schwarzer Sent: 24 August 2006 13:45 To: MAPSERVER-USERS@LISTS.UMN.EDU Subject: Re: [UMN_MAPSERVER-USERS] Mapscript Re-Projection on-the-fly Hey, I can't imagine that such a question stays unanswered in the mapserver community... I meanwhile added a: $map -> setProjection("init=epsg:26711"); to my code, but nothing happens - meaning: no error message but no reprojection either. Can anyone help me out? Thanks in advance. Stefan On Aug 22, 2006, at 10:47 AM, Stefan Schwarzer wrote: Gush, I couldn't find any precise information about how to re-project layers on-the-fly via PHP Mapscript. Here and there (via MailingList and Google) bits and pieces, but altogether it didn't help me a lot. Though I would have said that this is a basic question. But perhaps too basic, so everbody finds out by himself? So, can anyone let me know - giving a coding example - how to re-project a mapfile on-the-fly from for example Lat/Long (global view) to Lambert or Robin?  Thanks a lot for your help!