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Rethinking revision 12471
by mathog 28 Aug '13

28 Aug '13

I recently became aware of revision 12471, and overall, I am afraid that the way in which it was implemented is detrimental to the readability and future maintenance of the Inkscape code. Presumably the underlying function it implements is to allow changes in the ratio PX/IN, and other units of measurement, and I have no issue with that goal. However, prior to 12471 all of the unit relationships were neatly set up in a set of defines in src/unit-constants.h which defined things like PX_PER_IN which were used elsewhere in the code. These evaluated to static values, and the new ones do not, but that does not negate the usefulness of the define. 12471 removes all of these defines and makes substitutions throughout the code where PX_PER_IN is replaced by Inkscape::Util::Quantity::convert(1, "in", "px") My first criticism is that the new quantity is at first glance, indeterminate. Is it converting IN to PX or vice versa, what does "1" do? My second criticism is that eliminating the defines results in hundreds of substitutions in 12471 that are entirely unnecessary. All that was required was to change the defines in src/unit-constants.h, for instance from #define PX_PER_IN (PT_PER_IN / PT_PER_PX) to #define PX_PER_IN Inkscape::Util::Quantity::convert(1, "in", "px") after which virtually no changes elsewhere in the code are required. By doing that, the existing and relatively clear code, like: p0[X] = (p0[X] * IN_PER_PX * dwDPI); need not become the obfuscated (to my mind) form: p0[X] = (p0[X] * Inkscape::Util::Quantity::convert(1, "px", "in") * dwDPI); Before 12471 PX_PER_IN already evaluated to a complex expression, and the whole point of the define was to let the compiler handle that mess and only present to the programmer a short easily understood term. 12471 is a step backwards in this regard. Regards, David Mathog mathog@...1176... Manager, Sequence Analysis Facility, Biology Division, Caltech

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Fwd: Modifications to RecolorWheelPrivate
by Krzysztof Kosiński 28 Aug '13

28 Aug '13

2013/8/27 Arshdeep Singh <moduli16@...400...>: > I added: > new (&(priv->nodes)) std::map<std::string,RecolorWheelNode>(); > to recolor_wheel_init (RecolorWheel *wheel) . > > Honestly I have never seen this style of code, so I really don't understand > what it does. The good news is it does get to run the dialog box of 'Recolor > Artwork' i.e. no error while the dialog is loaded, but the moment I draw a > shape (active selection) the application crashes. This 'style of code' is known as 'placement new' and it calls the constructor of an object with an explicit 'this' pointer. It needs to be used when memory for an object is allocated from a different source than operator new. In normal C++, placement new is rarely used, because objects are typically allocated and constructed at the same time with operator new. However, if you allocate memory from a different source (in this case from GObject), you need to call the constructor yourself. http://en.wikipedia.org/wiki/Placement_syntax > Also my init function looks like this (for a quick browse, if needed): > > static void > recolor_wheel_init (RecolorWheel *wheel) > { > > RecolorWheelPrivate *priv; > > priv = G_TYPE_INSTANCE_GET_PRIVATE (wheel, RECOLOR_TYPE_COLOR_WHEEL, > RecolorWheelPrivate); > > wheel->priv = (RecolorWheelPrivate*)priv; > priv = (RecolorWheelPrivate*)wheel->priv ; What is the point of the last line? Why the casts? They are unnecessary. > What I don't undersytnd is how to initilaize a static object. > RecolorWheelPrivate has other static members like : What exactly do you mean by "static members"? The structure you provided does not define any static members. > gdouble h,s,v don't need explicit initializers. Why so ? Is it that the only > map object requires an explicit initilization. If so, why ? 'gdouble' is a primitive type (a typedef of 'double') which doesn't have any constructors. GObject zeroes memory by default, so if you don't assign to h, s, v they are left as all zeroes, which corresponds to the double value of 0.0. Regards, Krzysztof

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XDG Templates
by Martin Owens 28 Aug '13

28 Aug '13

I was reviewing the templates work by Jan Darowski and it got me thinking about the FreeDesktop.org XDG spec; it has a provision for a templates directory that we should be using instead of (or as well as) ~/.config/inkscape/ which is hidden from the user. This only applies to FreeDesktops/XDG complient desktops. But it would be useful. http://freedesktop.org/wiki/Software/xdg-user-dirs/ Example: XDG_TEMPLATES_DIR="$HOME/Templates" Thoughts?

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Re: [Inkscape-devel] Modifications to RecolorWheelPrivate
by Arshdeep Singh 28 Aug '13

28 Aug '13

Hi, Recap: I made a separate container for RecolorWheel. Initially there was an initialization error that crashed the application. As pointed out by Krzysztof, the std::map<std::string, RecolorWheelNode> had to be explicitly initialized which made the crash go away. The Recolor Dialog box renders perfectly. Invoking the DialogBox in Inkscape was causing a crash (before the explicit initialization of map) . Unfortunately, the application still crashes when I draw a new object on the canvas. Basically the crash happens when I select an object on the canvas. I was debugging the errors in gdb using g_message but here is the tricky part: When I run the inkscape.exe without gdb the application crashes only when the RecolorArtwork Dialog is active and an object on the canvas is selected. But, in gdb the application starts constantly giving the warning: " HEAP: Free heap block a90b8f6 modified at a90b8f6 after it was freed. " As a result the application doesn't get to the point where I can invoke RecolorArtwork and debug it. My latest branch can be found at: https://code.launchpad.net/~moduli16/inkscape/recolor . Regards, Arshdeep On Wed, Aug 28, 2013 at 2:38 AM, Arshdeep Singh <moduli16@...400...> wrote: > By static I meant 'non pointer' variables. Okay so this doesn't seem to be > the problem causing the crash. Gdb ends up showing the same heap error I > started this thread with. Can you spot an error as to why that keeps > happening ? > On Aug 28, 2013 2:25 AM, "Krzysztof Kosiński" <tweenk.pl@...400...> wrote: > >> 2013/8/27 Arshdeep Singh <moduli16@...400...>: >> > I added: >> > new (&(priv->nodes)) std::map<std::string,RecolorWheelNode>(); >> > to recolor_wheel_init (RecolorWheel *wheel) . >> > >> > Honestly I have never seen this style of code, so I really don't >> understand >> > what it does. The good news is it does get to run the dialog box of >> 'Recolor >> > Artwork' i.e. no error while the dialog is loaded, but the moment I >> draw a >> > shape (active selection) the application crashes. >> >> This 'style of code' is known as 'placement new' and it calls the >> constructor of an object with an explicit 'this' pointer. It needs to >> be used when memory for an object is allocated from a different source >> than operator new. >> >> In normal C++, placement new is rarely used, because objects are >> typically allocated and constructed at the same time with operator >> new. However, if you allocate memory from a different source (in this >> case from GObject), you need to call the constructor yourself. >> >> http://en.wikipedia.org/wiki/Placement_syntax >> >> > Also my init function looks like this (for a quick browse, if needed): >> > >> > static void >> > recolor_wheel_init (RecolorWheel *wheel) >> > { >> > >> > RecolorWheelPrivate *priv; >> > >> > priv = G_TYPE_INSTANCE_GET_PRIVATE (wheel, RECOLOR_TYPE_COLOR_WHEEL, >> > RecolorWheelPrivate); >> > >> > wheel->priv = (RecolorWheelPrivate*)priv; >> > priv = (RecolorWheelPrivate*)wheel->priv ; >> >> What is the point of the last line? Why the casts? They are unnecessary. >> >> > What I don't undersytnd is how to initilaize a static object. >> > RecolorWheelPrivate has other static members like : >> >> What exactly do you mean by "static members"? The structure you >> provided does not define any static members. >> >> > gdouble h,s,v don't need explicit initializers. Why so ? Is it that the >> only >> > map object requires an explicit initilization. If so, why ? >> >> 'gdouble' is a primitive type (a typedef of 'double') which doesn't >> have any constructors. GObject zeroes memory by default, so if you >> don't assign to h, s, v they are left as all zeroes, which corresponds >> to the double value of 0.0. >> >> Regards, Krzysztof >> > -- Arshdeep Singh Third Year, Computer Engineering Delhi Technological University Ph: +91-9654115614 https://sites.google.com/site/adsingh1729/home

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OpenMP support for Clang
by Samuel Chase 27 Aug '13

27 Aug '13

Hello Inkscape Developers, I just came across this: http://clang-omp.github.io/ . I guess once this makes it into Clang, we'll be able to create fully featured (i.e. OpenMP support enabled) Inkscape builds with clang++. Haven't tested anything so far, but this is still an interesting development... Samuel

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Fix for #771957: interleaved text and graphics in pdf+latex output
by David R. Bild 27 Aug '13

27 Aug '13

The current implementation of pdf+latex renders all text objects (LaTeX) above all graphical objects (PDF). I needed to export a figure with text interleaved with graphics---essentially bug #771957---so I implemented a simple fix for it. I'd like to see this (or, more likely, a modified version) merged for 0.49, but I'm not sure who maintains the pdf+latex renderer. Please let me know how to help. The code is at https://code.launchpad.net/~drbild/inkscape/multilayer-pdf-latex-output -- David -- David R. Bild Graduate Student EECS Department University of Michigan 1301 Beal Ave. Ann Arbor, MI 48109

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Fwd: Modifications to RecolorWheelPrivate
by Arshdeep Singh 26 Aug '13

26 Aug '13

---------- Forwarded message ---------- From: Arshdeep Singh <moduli16@...400...> Date: Mon, Aug 26, 2013 at 1:22 PM Subject: Modifications to RecolorWheelPrivate To: Ted Gould <ted@...11...>, Krzysztof Kosiński <tweenk.pl@...400...> Hi, I added a map object by the name 'nodes' to RecolorWheelPrivate: std::map<std::string,RecolorWheelNode> nodes; I then added this snippet for painting recolor nodes from the map: for (std::map<std::string,RecolorWheelNode>::iterator iter = priv->nodes.begin(); iter != priv->nodes.end(); ++iter) { dist = (*iter).second._color[1] * outer ; xx = center_x + cos ((*iter).second._color[0] * 2.0 * G_PI) * dist; yy = center_y - sin ((*iter).second._color[0] * 2.0 * G_PI) * dist; (*iter).second.x = (gfloat)xx; (*iter).second.y = (gfloat)yy; r = (*iter).second._color[0]; g = (*iter).second._color[1]; b = (*iter).second._color[2]; hsv_to_rgb (&r, &g, &b); } I added this snippet to performUpdate() in the recolor-artwork-widget.cpp : void RecolorArtworkWidget::performUpdate() { if ( update || !desktop ) { return; } if ( dragId ) { // local change; do nothing, but reset the flag g_source_remove(dragId); dragId = 0; return; } update = true; Inkscape::Selection *selection = sp_desktop_selection(desktop); GSList const *items = NULL; //int selObj = 0; if ( selection ) { items = selection->itemList(); //selObj = g_slist_length (const_cast<GSList*>(items)); RecolorWheel* wheel = (RecolorWheel*) (((RecolorWheelSelector*)(rsel))->getWheel()) ; RecolorWheelNode temp; for (GSList const *i = items; i != NULL; i = i->next) { SPObject *obj=reinterpret_cast<SPObject *>(i->data); Inkscape::XML::Node* obj_repr = obj->getRepr(); SPCSSAttr* obj_css = sp_repr_css_attr( obj_repr , "style" ); guint32 rgb32 = sp_svg_read_color( sp_repr_css_property( obj_css, "fill", "#ababab") , 0xF0F8FF ); SPColor color = SPColor (rgb32); float rgb[3] , hsv[3]; sp_color_get_rgb_floatv (&color, rgb); sp_color_rgb_to_hsv_floatv (hsv , temp._color[0] , temp._color[1] , temp._color[2] ); add_node_to_recolor_wheel (wheel, obj->getId() , temp ); } } update = false; } There seems to be some runtime error. Opening the RecolorArtwork Dialogbox crashes inkscape. Running gdb shows the warning that "HEAP: Free heap block a90b8f6 modified at a90b8f6 after it was freed" . Can't figure out whats making the application to crash. I have uploaded this branch too. It is the latest revision. -- Arshdeep Singh Third Year, Computer Engineering Delhi Technological University Ph: +91-9654115614 https://sites.google.com/site/adsingh1729/home -- Arshdeep Singh Third Year, Computer Engineering Delhi Technological University Ph: +91-9654115614 https://sites.google.com/site/adsingh1729/home

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[Units] Analysis of SVG Units
by Matthew Petroff 25 Aug '13

25 Aug '13

Sorry for my recent lack of updates. I was out of the country without a computer for a little over a week, was further delayed by a flight cancellation, and just got back. I had meant to post this update prior to leaving but didn't quite finish writing it in time. I have carefully read the SVG specification with regards to units, coming up with examples and a plan for implementation of real world units. http://www.mpetroff.net/archives/2013/08/24/analysis-of-svg-units/ -Matthew

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[Recolor] Progress Report
by Arshdeep Singh 24 Aug '13

24 Aug '13

Hello all, First of all apologies for being out of touch for so long. There was a placement drive in my college (which took place in October every year but was pre-poned to August this year) and hence I was busy studying. I resumed work on the project from 17th August. In a previous discussion with Ted and Krzysztof , it was concluded that making an all-together separate ColorSelector class for RecolorWheel would be better and much more convenient to code. I was busy doing that this week. Now what remains is to hookup the signals for the recolor wheel. The class nesting of Paint-Selector, GimpWheel etc has me caught a bit right now. I'll figure those out soon. Thanks. -- Arshdeep Singh Third Year, Computer Engineering Delhi Technological University Ph: +91-9654115614 https://sites.google.com/site/adsingh1729/home

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Image question
by mathog 23 Aug '13

23 Aug '13

On import of a 10 x 10 color 3 color bitmap from EMF (intrinsically "sharp") it is converted to the following SVG (sorry about the wrap): <image y="374.99722" x="404.997" xlink:href="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAoAAAAKCAIAAAACUFjqAAAAUElEQVQYlW2OwQ3AMAgDrxJjwP6DAXO0j1QJQfiFMGfzvBBKKG7DIAGgjIrfni4SQPwsrHJLmy4ZZdVsyKulhm/utBT6ytHbzv74uhDvXJV9Tw0bLHsWOIMAAAAASUVORK5CYII=" height="14.999889" width="14.999889" transform="matrix(1,0,0,1,0,0)" id="image4597" /> When viewed in Inkscape on either Linux or Windows there is what looks like a compression artifact, 1 pixel wide, all the way around the square. However, when viewed in Seamonkey, Firefox, or Opera it is sharp, with the colors just as expected from the original bitmap. (Opera is best for this, because it can zoom in further than the other two browsers.) What accounts for this? Is there some switch one can throw in Inkscape to disable whatever it is doing (anti-aliasing, maybe?) to cause this effect? Thanks, David Mathog mathog@...1176... Manager, Sequence Analysis Facility, Biology Division, Caltech

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