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</o:shapelayout></xml><![endif]--></head><body lang=EN-NZ link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Thanks Dave<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>I was not clear enough, -Head can have values; both, all, begin, end, whereas Q can be 0, 1, 2, 3, so some go-between is required.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>I finally looked and found part of it in source file thline.h<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>// tags pre arrow<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'> TT_LINE_TAG_HEAD_BEGIN = 1,<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'> TT_LINE_TAG_HEAD_END = 2,<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Presumably somewhere else NONE is set to or implied as zero and BOTH is set to BEGIN + END.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>That would complete the mapping from the data type that -Head takes as input in a th2 file, to the 0, 1, 2 or 3 that ‘line arrow’ requires for variable Q.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>I rather suspect I don’t have the requisite knowledge for this, but sometimes I feel the need to push the boundaries anyway!<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>:)<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Bruce<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US>From:</span></b><span lang=EN-US> Therion <therion-bounces@speleo.sk> <b>On Behalf Of </b>Dave Clucas via Therion<br><b>Sent:</b> Saturday, 31 March 2018 2:28 PM<br><b>To:</b> therion@speleo.sk<br><b>Cc:</b> Dave Clucas <dave.clucas@icloud.com><br><b>Subject:</b> Re: [Therion] scaling line ornamentation - metapost (Bruce Mutton)<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>I’m not sure about this but I suspect that it doesn’t involve parsing. It’s likely that the metapost expects a parameter or parameters to be passed to it which it then assigns to the variable Q in its own procedure. It won’t care what the calling program calls it. I think the arrowhead is probably defined within an arrow class (arrow.h perhaps).<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p><div><div><div><div><div><div><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p></div></div></div></div></div></div><div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>On 30 Mar 2018, at 18:00, <a href="mailto:therion-request@speleo.sk">therion-request@speleo.sk</a> wrote:<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica",sans-serif'>I notice line arrow takes the special argument -head [both | none | begin].<br>Somewhere between the th2 file and the metapost arrow definition, the<br>argument -head gets changed to the variable Q that is parsed to the metapost<br>code, that controls which ends of the arrow line get arrow heads. I have<br>copied the code below. Whereabouts is the code that tells Therion that<br>-head is parsed to the metapost definition as Q?<br style='font-variant-caps: normal;text-align:start;-webkit-text-stroke-width: 0px;word-spacing:0px'><br></span><o:p></o:p></p></div></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></div><p class=MsoNormal style='margin-bottom:12.0pt'><o:p> </o:p></p><div id=AppleMailSignature><div><div><div><div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='color:black'>Dave Clucas<br><a href="mailto:daveclucas@icloud.com"><span style='font-family:"Helvetica",sans-serif'>dave.clucas@icloud.com</span></a><br><br></span><b><span style='font-size:10.5pt;color:black'>Exploring the World</span></b><span style='font-family:"Helvetica",sans-serif;color:black'> - One cave at a time</span><span style='color:black'><o:p></o:p></span></p></div></div></div></div></div></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>