[gdal-dev] Usage of styles in C API

[Even Rouault]

Le dimanche 03 août 2014 12:53:00, Chaitanya kumar CH a écrit :
> I'll add these checks to the method that reads the ofs file. Ticket #5602

You mean a check to reject those lines or to accept them and ignore the 
leading spaces ?

Make sure to extend autotest/ogr/ogr_style.py that I had initiated when 
mapping the OGR_STBL_ methods to SWIG.

> 
> On 3 Aug 2014 16:15, "Even Rouault" <even.rouault at mines-paris.org> wrote:
> > Le dimanche 03 août 2014 12:41:56, Nik Sands a écrit :
> > > Sorry, my mistake... I had my logging in the wrong place.  styleChars
> > > is
> > > 
> > > actually of the form (including the leading space):
> > >       ' PEN(c:#A08080,w:2pt); LABEL(c:#000000,s:18pt,t:{title})'
> > 
> > The issue must be the leading space before PEN, and potentially LABEL
> > too.
> > 
> > > On 3 Aug 2014, at 8:35 pm, Nik Sands <nixanz at nixanz.com> wrote:
> > > > On one of the iterations through this code, styleChars is:
> > > >     'vegetation_low: BRUSH(fc:#A0F0A0);
> > 
> > LABEL(c:#004000,s:18pt,t:{title})'
> > 
> > > > So perhaps the inclusion of the style name is the problem?
> > > > 
> > > > This was read into a style table from a text file using
> > > > 'OGR_STBL_LoadStyleTable()'.  I had assumed that a similar format to
> > > > .ofs was suitable.  If this is not the case, how should I read a
> > > > style table from a text file in such a way that I can distinguish
> > > > the various styles by name?
> > > > 
> > > > In guess my more general question is:  What is the correct way to
> > > > read styles from an arbitrary text file into a style table, and then
> > > > use a style manager to get the various parts/tools?
> > > > 
> > > > On 3 Aug 2014, at 8:26 pm, Even Rouault
> > > > <even.rouault at mines-paris.org>
> > 
> > wrote:
> > > >> Le dimanche 03 août 2014 12:11:42, Nik Sands a écrit :
> > > >>> I'm just starting out using the styles features of OGR (using the C
> > > >>> API) but at struggling with a few elements of it.
> > > >>> 
> > > >>> My code (copied below) fails to get any OGRStyleToolH.  Ie, the "if
> > > >>> ( tool )" block never gets run, because 'tool' is always NULL at
> > > >>> the point indicated by the comment.  But the execution does reach
> > > >>> that point in the code which indicates that the OGRStyleMrgH does
> > > >>> in fact include at least one part (tool).
> > > >>> 
> > > >>> I'd be grateful if somebody could point out what I'm doing wrong.
> > > >> 
> > > >> Nothing strikes me as wrong. A potential explanation is that
> > 
> > styleChars
> > 
> > > >> doesn't contain a valid OGR Feature Style string.
> > > >> GetPartCount() counts the number of ";" separating style parts, but
> > > >> it doens't check that each style part actually begins by a
> > > >> recognized
> > 
> > tool
> > 
> > > >> name (PEN, BRUSH, SYMBOL, LABEL). OGR_SM_GetPart() does this check
> > > >> however and if it cannot recognize it it returns a NULL tool.
> > > >> 
> > > >>> Thanks,
> > > >>> Nik.
> > > >>> 
> > > >>> 
> > > >>> -------------------------------------------
> > > >>> 
> > > >>>   const char *styleChars = OGR_STBL_GetNextStyle(table) ) )
> > > >>>   NSString *styleName = [NSString
> > > >>> 
> > > >>> stringWithUTF8String:OGR_STBL_GetLastStyleName(table)];
> > > >>> OGRStyleMgrH styleMgr = OGR_SM_Create(NULL);
> > > >>> 
> > > >>>   OGR_SM_InitStyleString(styleMgr, styleChars);
> > > >>>   
> > > >>>   
> > > >>>   for ( int i = 0; i < OGR_SM_GetPartCount(styleMgr, NULL); i++ )
> > > >>>   {
> > > >>>   
> > > >>>           OGRStyleToolH tool = OGR_SM_GetPart(styleMgr, i, NULL);
> > > >>>           
> > > >>>           if ( tool )  //  'tool' always NULL here
> > > >>>           {
> > > >>>           
> > > >>>                   switch ( OGR_ST_GetType(tool) )
> > > >>>                   {
> > > >>>                   
> > > >>>                           case OGRSTCPen:
> > > >>>                                   self.pen = tool;
> > > >>>                                   break;
> > > >>>                           
> > > >>>                           case OGRSTCBrush:
> > > >>>                                   self.brush = tool;
> > > >>>                                   break;
> > > >>>                           
> > > >>>                           case OGRSTCSymbol:
> > > >>>                                   self.symbol = tool;
> > > >>>                                   break;
> > > >>>                           
> > > >>>                           case OGRSTCLabel:
> > > >>>                                   self.label = tool;
> > > >>>                                   break;
> > > >>>                           
> > > >>>                           default:
> > > >>>                                   NSLog(@"Unknown style tool
> > > >>>                                   type!"); break;
> > > >>>                   
> > > >>>                   }
> > > >>>           
> > > >>>           }
> > > >>>   
> > > >>>   }
> > > >>> 
> > > >>> -------------------------------------------
> > > >>> 
> > > >>> 
> > > >>> _______________________________________________
> > > >>> gdal-dev mailing list
> > > >>> gdal-dev at lists.osgeo.org
> > > >>> http://lists.osgeo.org/mailman/listinfo/gdal-dev
> > > > 
> > > > _______________________________________________
> > > > gdal-dev mailing list
> > > > gdal-dev at lists.osgeo.org
> > > > http://lists.osgeo.org/mailman/listinfo/gdal-dev
> > 
> > --
> > Geospatial professional services
> > http://even.rouault.free.fr/services.html
> > _______________________________________________
> > gdal-dev mailing list
> > gdal-dev at lists.osgeo.org
> > http://lists.osgeo.org/mailman/listinfo/gdal-dev

-- 
Geospatial professional services
http://even.rouault.free.fr/services.html