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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Graham,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>At a glance looks good and I love the diagrams.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>The doc doesn’t seem to mention how to use the API, more conceptual stuff. I assume that will come once your API is more fleshed out. Would be interesting to see the code. Probably easier to see major mistakes misunderstandings that way.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>So which language are you creating this wrapper in? I am assuming C since you mentioned in your document<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>“</span>With these two constraints, there appeared to be nothing available that would offer the functionality I wanted in a pure C package. Or so I thought, until I discovered a feature of LibGEOS that I had overlooked in my original research. LibGEOS is written in C++, but - unlike many other C++ packages which are accessible from C only through complex interfacing methods (writing in C but compiling with a C++ compiler, or performing nasty name-mangling tricks at link time, or writing cross-calling interface procedures that can't access all the C++ procedures) - this package came with a plain C interface already built. It was accessible through a Unix header file and accompanying library that could be accessed from standard C with no C++ involvement at all other than building the initial library with the supplied make files, and for most target systems LibGEOS could in fact be installed with a simple 1-line command using the system's package manager.”<span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>With that said, might be helpful to look at some other projects that use the C-API like “PostGIS”, or maybe you have already (all the files in that folder with geos in the name are wrappers around GEOS api:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><a href="https://git.osgeo.org/gitea/postgis/postgis/src/branch/master/liblwgeom">https://git.osgeo.org/gitea/postgis/postgis/src/branch/master/liblwgeom</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>and shapely comes to mind too<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><a href="https://github.com/shapely/shapely/blob/main/src/geos.c">https://github.com/shapely/shapely/blob/main/src/geos.c</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Sad yes GEOS doesn’t handle curves, and GIS people seem to not care.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>We need CAD folks. </span><span style='font-size:11.0pt;font-family:Wingdings;color:#1F497D'>J</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Funny you mention CNC machines, brought back some fond memories. In my high school we had a huge CNC machine<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>and it was my first reallish use of applying geometry lessons. The CNC machine was the only thing I liked about that Woodworking and Machine Shop class we were all required to take.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Hope that helps,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Regina<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> geos-devel [mailto:geos-devel-bounces@lists.osgeo.org] <b>On Behalf Of </b>Graham Toal<br><b>Sent:</b> Saturday, January 28, 2023 6:41 PM<br><b>To:</b> geos-devel@lists.osgeo.org<br><b>Subject:</b> [geos-devel] Writing a wrapper around LibGEOS<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>I'm writing an interface library to wrap around LibGEOS which I hope will simplify its use a little in other domains besides GIS. (Mainly for myself but I'm documenting it in case it's useful to anyone else.)<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Rather than look at the (currently somewhat fluid) API, I was hoping one or two people familiar with the GEOS package would have a quick look over the first (incomplete) draft of the document that I'm writing for it, and pass on any major criticisms if I have got anything seriously wrong so far.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> <a href="http://gtoal.com/src/polygon/Manual.html">http://gtoal.com/src/polygon/Manual.html</a><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I haven't documented the API yet as it's not finalised; I'm making changes as I document everything. The 'TO DO' section at the end is not part of the document - those are just notes to myself.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Follow up by email (<a href="mailto:gtoal@gtoal.com">gtoal@gtoal.com</a>) or reply here, whichever you think is more appropriate. Thanks,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Graham<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></body></html>