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

[Stefan Schwarzer]

Jacob, Nicol, Ahhhh.... bit irritating these different coding possibilities... Ok, I met the original definition to all layers AND the map file: PROJECTION 'init=epsg:4326' END and when using  $newproj="proj=robin,lon_0=0,x_0=0,y_0=0"; // projection string of your new projection $map->setProjection($newproj,MS_TRUE); it indeed works! Great, thanks a lot guys for that help!!! Best regards, Stef On Aug 24, 2006, at 10:05 AM, Delfos, Jacob wrote: Hi Stefan,   Yes, you do have to specify which projection each layer is in, otherwise when they are reprojected you will run into trouble (if it doesn't know where to reproject FROM, it won't be able to do i). It's not too hard, though.   You should not have to recalculate the extent; it should be automatic. Definitely don't try to change the numbers (coordinates) without changing the projection (that would be bad).   Try this:   $newproj="proj=robin,lon_0=0,x_0=0,y_0=0"; // projection string of your new projection $map->setProjection($newproj,MS_TRUE);   I think that ought to be all.  The MS_TRUE makes it pick the best fit to the current extent in the new projection. Make sure your projection string is valid.   regards,   Jacob     From: UMN MapServer Users List [mailto:MAPSERVER-USERS@LISTS.UMN.EDU] On Behalf Of Stefan Schwarzer Sent: 24 August 2006 15:35 To: MAPSERVER-USERS@LISTS.UMN.EDU Subject: Re: [UMN_MAPSERVER-USERS] Mapscript Re-Projection on-the-fly 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!