Is there a way to integrate a shape (e.g. a <rect>) in an SVG text as if it were a character?
It should look something like this (with a simple rectangle in this example, but possibly arbitrary other graphics in the actual application):
In other words, essentially like the common functionality found in text editors (such as MS Word or OpenOffice Writer) to anchor an image in the text flow rather than at an absolute position.
Ideally, the markup should be as straightforard as this (pseudo-code):
<text><tspan>Hello, </tspan><rect width="10px" height="10px" fill="blue"/><tspan>World!</tspan></text>
However, according to the specification, it is not possible to add shape elements directly as children of either <text> or <tspan>. <altGlyph> sounds like it might be a solution, but I failed to find out how to use it, and examples for that element are extremely sparse.
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I would like to generate some diagram style graphics using SVG and use text in the diagrams. My problem is, how to know the size of the text in advance to be able to adjust the rest of the layout accordingly. To make this explicit: I'm not talking about SVG in a browser. I would like to work with fixed units and generate PDF for printing for example. So if I use a 12pt font, it should also be printed as 12pt font.
To have a more concrete example: Lets assume I have the three strings "bla", "blablub" and "blubblablub". I would like to print them in a given 12pt font, determine the string size and enclosing boxes and draw the biggest sized box around all of them. The idea is to have equally sized boxed around all, based on the longest text.
Could somebody give me a hint how to do that or why it is not possible? Searching for this topic, I only get some JavaScript tricks in the browser, which usually involves rendering the text and then re-rendering everything again.
Using HitTestTextPosition style API from IDWriteTextLayout I did not managed to handle properly text positions inside "ti", "ffi" or other ligatures with fonts like Calibri. It always returns position after or before ligature not inside like t|i or f|f|i.
What is the recommended way to do a caret movement inside ligatures with DirectWrite API?
There... is no "inside" position if you have GSUB replacements turned on?
Opentype GSUB ligatures are single glyph replacements for codepoint sequences, rather than being "several glyphs, smushed together". They are literally distinct, single glyphs, with single bounding boxes, and a single left and right side bearing for cursor placement/alignment. If you have the text A + E and the font has a ligature replacement that turns it into Ӕ then with ligatures enabled there really are only two cursor positions in that code sequence: |Ӕ and Ӕ|. You can't place the cursor "in the middle", because there is no "middle"; it's a single, atomic, indivisible element.
The same goes for f. ligatures like ff, fi, fl, ffi, ffl, or ſt: these are single glyphs once shaped with GSUB turned on. This is in fact what's supposed to happen: having GSUB ligatures enabled means you expressly want text to be presented—for all intents and purposes—as having atomic glyphs for many-to-one substitutions, like turning the full phrase "صلى الله عليه وعلى آله وسلم", as well as variations of that, into the single glyph ﷺ.
If you want to work with the base codepoint sequences (so that if you have a text with f + f + i it doesn't turn that into ffi) you will need to load the font with the liga OpenType feature disabled.
The text editors I know of use the simple hack of (1) dividing the width of the glyph cluster by the number of code points within the cluster (excluding any zero width combining marks), rather than use the GDEF caret positioning information. This includes even Word, which you can tell if you look closely enough below. It's not precise, but since it's simple and close enough at ordinary reading sizes, it's what many do:
(2) I've heard that some may (but don't know which) also use the original glyph advances of the unshaped characters (pre-ligation) and scale them proportionally to the ligature cluster width.
(3) Some text editors may use the GDEF table, but I never knew of any for sure (possibly Adobe In-Design?).
The most challenging aspect of using methods 2 or 3 with IDWriteTextLayout is that accessing the corresponding IDWriteFontFace in that run requires quite the indirection because the specific IDWriteFontFace used (after resolving font family name+WWS+variable font axes) is stored in the layout but not publicly accessible via any "getter" API. The only way you can extract them is by "drawing" the glyph runs via IDWriteTextLayout::Draw into a user-defined IDWriteTextRenderer interface to record all the DWRITE_GLYPH_RUN::fontFace's. Then you could call IDWriteFontFace::GetDesignGlyphAdvances on the code points or IDWriteFontFace::TryGetFontTable to read the OpenType GDEF table (which is complex to read). It's a lot of work, and that's because...
The official PadWrite example has the same issue
IDWriteTextLayout was designed for displaying text rather than editing it. It has some functionality for hit-testing which is useful if you want to display an underlined link in a paragraph and test for it being clicked (in which case the ligature would be whole anyway within a word), or if you want to draw some decorations around some text, but it wasn't really intended for the full editing experience, which includes caret navigation. It was always intended that actual text editing engines (e.g. those used in Word, PowerPoint, OpenOffice, ...) would call the lower level API's, which they do.
The PadWrite sample I wrote is a little misleading because although it supports basic editing, that was just so you can play around with the formatting and see how things worked. It had a long way to go before it could really be an interactive editor. For one (the big one), it completely recreated the IDWriteTextLayout each edit, which is why the sample only presented a few paragraphs of text, because a full editor with several pages of text would want to incrementally update the text. I don't work on that team anymore, but I've thought of creating a DWrite helper library on GitHub to fill in some hindsight gaps, and if I ever did, I'd probably just ... use method 1 :b.
is it possible to create a stroke with a dynamic width with SVG? I want to achieve a Calligraphy look like here, here or here.
Is this even possible? It seems customization of strokes in SVG is fairly limited. Even gradients in strokes seem to be non-trivial (see here).
There is a proposal to add into SVG standard a mechanism, that does exactly what you want:
http://www.w3.org/Graphics/SVG/WG/wiki/Proposals/Variable_width_stroke
http://lists.w3.org/Archives/Public/www-svg/2013May/0041.html
There's even an example implementation available here:
https://rawgit.com/birtles/curvy/master/index.html
It is, however, by no means official and we cannot be even sure it'll ever be.
Until then you'll need to stick to Bezier curves and object filling:
You can also use calligraphic fonts, for example - Tangerine available on Google CDN:
This approach requires less work since you don't need to draw everything from scratch, but then again, using third party fonts leaves you with little control over the final result.
You can't dynamically adjust the stroke of a path element. However you could draw a path, use a fill color on it instead of stroke, then double back upon the letters at a slight distance away from the original line.
Also, if you are using the SVG on the web then you can use css fonts on text elements. There are some pretty good cursive fonts that you can use for free... just check google web fonts.
I've setup a drawing utility with Raphael.js. The user can draw shapes, paths and enter text. Once a user adds text -> Paper.text() to the svg the svg goes into a selectable state. Meaning, if I add text and switch to the pen tool, moving the pen around the svg will cause adjacent dom elements to go into their ::selection state.
So I'd like to convert the text to a path to prevent this from happening. I don't see anything like this in the documentation.
if you use print() instead of text() for text printing, then the text will be a raphael path object. (print() use a cufon javascript font that renders to a raphael path).
Try tweaking the pointer-events property on the text elements with .attr(). none might fit your needs. There are some good background info links on MDN.
.attr({pointer-events: none})
I'm interested how to construct certain kinds of layout in RTF documents, ideally using techniques that do not depend only on the most recent RTF standards, and that are "native", i.e., they do not involve embedding other representations, like picture files. In particular:
In Postscript and DVI, I can specify a coordinate at any time that the next text will be printed at: can this be done with RTF?
Can RTF compose characters through overstriking?
Can lines, outline boxes and filled boxes be drawn, with their geometry specified either absolutely, or relative to text?
You can use the \pvpg \phpg \posx123 \posy123 construct after
you start a paragraph with \pard to position it relative to the top left of the page. See: http://biblioscape.com/rtf15_spec.htm#Heading39
Yes, but it's rather involved, and I think it was only introduced in RTF 1.5. See the drawing objects section of the spec. Here is a basic example of drawing a box (I'm not sure it's entirely valid but it should give you an idea of how to work with drawing objects):
{\rtf1\ansi\deff0
{\pard {\*\do
\dobxcolumn \dobypara
\dprect \dpx0 \dpy0 \dpxsize1000 \dpysize1000 \dplinew25
}\par}
}
If you're doing any work with RTF it's worth picking up O'Reilly's RTF Pocket Guide.
I don't believe this is possible. You'd need to use tabs and newlines to get the text where you want it.
Not really, unless \strike and \strikedl count.
http://www.biblioscape.com/rtf15_spec.htm#Heading52 says drawing objects are an option, and so is inserting images, but neither are really "native", both being absent in the first RTF specs. (And the latter is a bad choice for i.e. just a line.)