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Re: [Inkscape-devel] Why is the position of this line of code so touchy?
by Krzysztof Kosiński 24 Jan '14

24 Jan '14

2014/1/24 mathog <mathog@...1176...>: >> This line is completely equivalent to replacing it with a call to >> cairo_save and adding a call to cairo_restore at the very end of the >> containing scope. >> >> You cannot move this line into a different function, because then the >> destructor (and hence cairo_restore) gets called when decorateItem() >> returns. > > Except my code ONLY works if it is moved into another function! That's what > is driving me nuts. I will have to trace this code thoroughly, as there > must be a dangling transformation or an extra cairo_restore or cairo_save > somewhere. Please post a more complete listing of the good and the malfunctioning version of your code. I'm sure we'll find the problem then. The "call, line1, line2" etc. descriptions in your initial e-mail are a little insufficient to figure out what is going on. > I guess. I am not a fan of implicit side effects unless there is absolutely > no way around it. Here > > dc.save() > blah > dc.restore() > > would have worked, and it would have been immediately apparent to a > maintenance programmer what was going on. Or is the ::Save stuff in there > to clean up in case there is an exception and the code jumps to a handler, > without ever returning from these functions? You can add an early return and forget about adding the cleanup code, there can be an exception, or you can simply forget about adding he restore(). The ::Save object ensures proper cleanup in all of those possibilities. Regards, Krzysztof

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C++ explanation please
by mathog 24 Jan '14

24 Jan '14

Sometimes it is hard to shake off decades of C programming, so please bear with. In src/display/drawing-context.h near the top one finds: class DrawingContext : boost::noncopyable { public: class Save { public: Save(); Save(DrawingContext &ct); ~Save(); void save(DrawingContext &ct); private: DrawingContext *_ct; }; and in drawing-context.cpp those methods all use ct and _ct for the variable names. Which is all fine and would be no issue at all, except that below the lines just cited in drawing-context.h every place one finds a reference to ct or _ct it is a cairo_t or a cairo_t*, not a DrawingContext. Can somebody please explain why it is considered helpful in C++ to use "ct" to mean two different things like this in the one header file? The disadvantage of doing it the way it is now is that when somebody like me encounters _ct elsewhere in src/display, and looks for it like this: grep '[\* ]_ct[; {]' src/display/*.h it finds two definitions: DrawingContext *_ct; and cairo_t *_ct; with the end result that one must read the file to figure out what is actually going on. Had the first set used "DC"/"_DC", for instance, there would have been no confusion, and the second step would have been eliminated. Thanks, David Mathog mathog@...1176... Manager, Sequence Analysis Facility, Biology Division, Caltech

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forward declarations janitorial task
by Guiu Rocafort 23 Jan '14

23 Jan '14

hi list. I'm taking a look at the janitorial task, specially to the forward declaration in the wiki[1]. But there is something i'm not sure about. You can use the forward declaration only if you're using the class as a pointer and without using any of its functions/attributes ? or is it just when using the class as a pointer ? for example, in attribute-rel-util.h, i can get rid of the xml/node.h include, but sp-css-attr.h doesn't seem to work. Am I missing something ? [1] http://wiki.inkscape.org/wiki/index.php/Janitorial_tasks#Improving_headers_… -- Please avoid sending me Word or PowerPoint attachments. See http://www.gnu.org/philosophy/no-word-attachments.html

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Fwd: Re: C++ explanation please
by mathog 23 Jan '14

23 Jan '14

On 22-Jan-2014 13:39, Johan Engelen wrote: > You have to trace the scope hierarchy > manually (e.g. function body -> class declaration -> base class > declaration(s)) This is probably a rant... Never mind tracing the variables, tracing execution to see which parts are actually used can be tedious too. I spent too much of the last day doing just that. Experimental text decoration display is currently in trunk, along with a patch (in Launchpad) that modifies the Text and Font dialog to allow crude editing of those properties. Now one might think that since Cairo is used for the display, and Cairo is used to render to PDF (and others), that implementing a type of draw for display would automatically show up in render. Nope, none of the text decorations render to a file. As far as I can tell the display and render functions are both intertwined, and separate. This is what happens when Inkscape saves to a PDF (just the highlights, obviously a lot of other stuff goes on too). Starting at (A) src/extension/internal/cairo_render_pdf_out.cpp (A) pdf_render_to_document_file() (C) (->B) (H) (->I) (T) DONE! src/sp_item.cpp (B) invoke_show (->D) (G) (return ->H) src/libnrtype/Layout-TNG-Output.cpp (D) Layout::show (->E) (F) (return ->G) (L) showGlyphs (->M) (P) (return ->Q) src/display/drawing_text.cpp (E) addcomponent (add a glyph to a list, copy some parts of style into _nrstyle) (return ->F) (Z) _renderItem (draws glyphs for cairo for DISPLAY of text) src/extension/internal/cairo_renderer.cpp (I) renderItem (->J) (S) (return ->T) (J) sp_item_invoke_rendering (->K) (R) (return ->S) (K) sp_text_render (->M) (Q) (return ->R) src/extension/internal/cairo_render_context.cpp (M) renderGlyphText (->N) (O) (return ->P) (N) showGlyphs (draws glyphs for cairo for RENDER of text) (->O) When text is displayed (on the drawing surface) it also follows a call to addcomponent (E) and (if there are changes(?)) Layout::Show (D), but goes through _renderItem (Z) in src/display/drawing_text.cpp, which is never called in the trace above. Text display doesn't touch the rest of the trace shown above. In _renderItem it deals with an object DrawingContext, whereas in the trace above it carries around an object CairoRenderContext. In terms of activity both of these objects are just wrappers around Cairo - but exceedingly different wrappers. _renderItem is fairly similar to renderGlyphText (M) [but ironically, not to renderItem(I)], so renderGlyphText (M) is one logical place to patch in text decorations for render. However, when I implemented text_decoration display, which is called from _renderItem (Z) the code naturally used DrawingContext and _nrstyle (E), and neither of those is available in renderGlyphText (M), which greatly complicates implementing text decoration for render. Maybe text draw and text render were designed to be this different, but it feels an awful lot like an instance of divergent evolution. Regards, David Mathog mathog@...1176... Manager, Sequence Analysis Facility, Biology Division, Caltech

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Href sub-document model (Martin Owens)
by Jelle Mulder 22 Jan '14

22 Jan '14

Hi Martin, Let me start with telling that I'm thrilled that you're doing work on external <use> links and have some working code. I hope it will find its way into the 0.91 version as it will make my life so much easier. However, while you're at it. Three questions arise. - Can this mechanism be used to add external CSS as well? I know Bruno Wick is working on that as well, but it seems you're on a roll here and would be the missing link (pun intended). - Would it be possible to create a save option where such external files are concatenated into one big whopper of a file? Or even better, send it all to a single root file of users choice (oh joy!)? With some nice check marks to add or not CSS, external <USE> objects, etc? It would solve a problem for all those browsers that do not support external linking or have bugs*. *(like webkit that supported external links till Chrome version 19 and then Blink had this nice regression that yet has to get solved. Opera works fine till version 12.5 and then they went Blink, Firefox can only handle links one directory level deep these days, sigh. I foresee a brighter future though) - And the very whopper question that probably stretches your patience.. How about kicking all <use> objects to external files and style info to external CSS? <script> to external files? Again with switches for each type of export. I gather this to be a whole other ball game and probably not ready for 0.91, but what power would that give to Inkscape as authoring tool for web projects! Ehm,.. sorry if this abuses the dev list as it sounds very much like something I should throw at the bugtracker wish list, but 95% of my request get timed out due to latency I experience in Chongqing, China, so I never manage to send something there. On the other hand, I think it is on topic. Jubilant cheers, Jelle Mulder > Message: 1 > Date: Tue, 21 Jan 2014 11:09:58 -0500 > From: Martin Owens <doctormo@...400...> > Subject: [Inkscape-devel] Href sub-document model > To: Inkscape Devel List <inkscape-devel(a)lists.sourceforge.net> > Message-ID: <1390320598.10117.59.camel@...2056...> > Content-Type: text/plain; charset="UTF-8" > > Hey developers, > > This is the model I'm going to implement for documents to reference > other documents: > > SPDocument { > GSList *child_documents; > SPDocument *parent_document; > > // Parent of parents until parent == NULL; > SPDocument *getRootDocument(); > } > > Then in uri-reference, check paths of existing child_documents, load the > referenced document and add to child_documents. Set parent_document. > > That should keep things consistant. > > The idea here is that we'll use this to track documents referenced in > <use tags> as well as <image tags> and attributes like 'marker-*: > url(...);' but not for non-vector graphics used in the image tag. > > Thoughts? Advice? > > Best Regards, Martin Owens

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What is the intended purpose of this line of code?
by mathog 21 Jan '14

21 Jan '14

Hi all, While trying to find a place to patch in text-decoration writes so that they show up in cairo based file types (PDF and the like), I noticed that simple multicharacter tspans were being broken into single glyph writes by this line in TNG-Output.cpp: && (font_matrix * glyph_matrix.inverse()).isIdentity() because the test is always false. Here is the link to it in context (barring edits to that file in a revision after I send this) http://bazaar.launchpad.net/~inkscape.dev/inkscape/trunk/view/head:/src/lib… If that one line is commented out it lets something like <tspan>123456</tspan> pass through to renderGlyphtext() in one big chunk, but other than that, it doesn't seem to make any difference. Can somebody tell me why that test is there? It seems to be doing the wrong thing in all the test cases I have run through it, unnecessarily breaking up the writes, but that doesn't mean that it does not resolve a problem that arises in some case I have not yet considered. Thanks, David Mathog mathog@...1176... Manager, Sequence Analysis Facility, Biology Division, Caltech

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Compile Inkscape - Problem Link DLL and .lib file
by naim 21 Jan '14

21 Jan '14

Hi I got a DLL and its .lib file that expose some functions. I need to use those functions to customize Inkscape. My question is, how do I configure build.xml so that compiler will link the .lib file? Thanks, Naim

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External SVG Files via href
by Martin Owens 21 Jan '14

21 Jan '14

Hey Devs, I've been looking into this bug: https://bugs.launchpad.net/inkscape/+bug/1269880 And have forged a solution in uri-references.cpp by using the existing getPath property and GLib's build_filename. See the commit here: http://bazaar.launchpad.net/~inkscape.dev/inkscape/trunk/revision/12939 I really didn't expect this to work, I thought it'd be step one in a chain of items to fix. But it actually works and I'd like other dev's input to see if it's doing the right thing. I'd like to have a document based list of linked documents, so they could be tracked (and maybe ui'ed in the future). But I'm not sure if it's even needed. Thoughts? Best Regards, Martin Owens

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Text decorations, GUI
by mathog 21 Jan '14

21 Jan '14

Display of text decorations is in trunk and it can display things as shown in this example: https://launchpadlibrarian.net/140347078/text_decorations.png (Note install the last patch in https://bugs.launchpad.net/inkscape/+bug/1243401 to see these again, as a recent change to trunk broke them.) Text decoration control requires three GUI fields: Line: NONE, or any combination of: underline, overline, linethrough, blink Style: solid, double, dashed, wavy Color: From Text or (Color setting widget) I'm thinking about what the GUI should look like to access these. My first thought was to add them to the "A" (Create and edit text objects) part of the GUI, since text decoration does not make a lot of sense without text to decorate, and this sort of thing would be in a part of the GUI like that in a Word processor. But that part of the GUI is already packed with options, to the extent that on my computer I can only see all the options when Inkscape fills the entire screen. If text decoration was added there, it would never all fit. So my second thought was to maybe put these in "A (with a wavy line through it)" as (Create and edit text decorations). That would let it fit on screen better, at the cost of making the line of icons down the left side of the screen one longer. The third option is to add a second line of options to the existing "A". That would use up more vertical screen space, but it would have the advantage that all of the text and text decoration formatting options could be on screen at once. This is more of a departure for the GUI, since it seems not to happen anywhere else. Thoughts? (Note: "blink" line type is emulated with a type of double line style. I don't expect true blink display to be found in many SVG viewers, ever, so all Inkscape has to do is indicate that it is set.) Is there at present anything in the Inkscape GUI where a check box widget is exposed when one of the left side icons is selected? As far as I could tell all of the widgets exposed by selecting one of those icons are of the "select one" type. Regards, David Mathog mathog@...1176... Manager, Sequence Analysis Facility, Biology Division, Caltech

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wiki.inkscape.org down
by Guiu Rocafort 20 Jan '14

20 Jan '14

Hi ! I noticed that the wiki page wiki.inkscape.org is down ( at least for me and from this page[1] ) Guiu [1] http://downforeveryoneorjustme.com/wiki.inkscape.org -- Please avoid sending me Word or PowerPoint attachments. See http://www.gnu.org/philosophy/no-word-attachments.html

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