xmlgraphics-batik-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From kototama kototama <kotot...@gmail.com>
Subject Re: getBBox values not consistent with Chrome
Date Wed, 20 Nov 2013 10:19:19 GMT
I'm modifying the DOM on the server (with Clojure) to serve it on a web
client. The DOM is exported to a stream and served.

I suppose SVGGraphics2D do not work in this context?

Exporting texts to paths is maybe not a solution for us as we would loose
the ability to search the text (with Ctrl-f for the user) in the browser.

Doing the manipulation in JavaScript is also problematic since resizing a
rectangle (node) on the client means adapting the coordinate of the edges
connecting two rectangles (we wrote layout algorithms on the server for
graphs).




On Tue, Nov 19, 2013 at 10:33 PM, Andrew Rowlands <a.rowlands@uq.edu.au>wrote:

> I would go with Robert’s text to shape suggestion for this.  Converting
> text to paths is the only reliable way to ensure the text will render as
> you expect across platforms.  This also applies for certain functions that
> are not supported by some versions of browsers, e.g. text on path.
>  Anything else will almost certainly not get the results you are after.
>
> Another way to do this (entirely depending on your application of course)
> is to do the manipulation in javascript - BUT - this obviously requires
> that the end user is running a nice latest-version browser with decent SVG
> support ;)
>
>
> On 20 Nov 2013, at 5:22 am, Robert Marcano <robert@marcanoonline.com>
> wrote:
>
> > On 11/19/2013 01:34 PM, kototama kototama wrote:
> >> Yes I'm calculating before the creation of the SVG.
> >>
> >> For solution 1), is there a standard function to do that?
> >
> > Are you drawing to a Batik SVGGraphics2D? if true, use the Java2D APIs
> to do that:
> >
> > TextLayout layout = new TextLayout("This is a string", font, frc);
> > Shape shape = layout.getOutline(null); // null if no transformation is
> > needed
> > g.draw(shape);
> >
> > SVGGraphics2D should probably have an API for enabling that, but I
> didn't find one
> >
> > If you are using Batik GVT, I don't remember much about it but I
> remember that you can get Java2D shapes from elements
> >
> >>
> >> For solution 2), isn't Helvetica a browser font?
> >
> > Browsers generally don't provide fonts (on Android some do because they
> need to embed them because the OS only provides basic UI fonts), they do
> some mapping to the OS available fonts. Someone that names a font Helvetica
> should try to provide the same metrics, on common Linux distributions
> Helvetica is mapped to Nimbus Sans L, that apparently tries to do that.
> >
> > Trying to draw pixel perfect fonts with SVG on browsers is like trying
> to draw pixel perfect HTML text. There are many issues that can make your
> drawing not look the same, for example differences in how the text layout
> code of the browser paint each glyph, if ligatures are supported, etc.
> >
> > But assuming the browser is using the exact same font you are using on
> Java (same computer both tests), you can try using the viewbox attribute
> http://www.w3.org/TR/SVG/coords.html#ViewBoxAttribute . Everytime I get
> an SVG file that mixes pixel units and relative units like pt, in, cm, etc.
> Everything looks distorted on other viewers/User Agents that use different
> base DPI values
> >
> >>
> >> Also why the same fonts can have different metrics in different
> browsers?
> >>
> >>
> >> On Tue, Nov 19, 2013 at 6:35 PM, Robert Marcano
> >> <robert@marcanoonline.com <mailto:robert@marcanoonline.com>> wrote:
> >>
> >>    On 11/19/2013 12:44 PM, kototama kototama wrote:
> >>
> >>        Hello,
> >>
> >>        I'm calculating the bbox value of a group containing a rectangle
> to
> >>        adapt its dimension to the text it contained.
> >>
> >>
> >>    If the calculation is not dynamic, but done on Java before dumping
> >>    the SVG XML, the problem may be related to the real font used. There
> >>    is no guarantee that the UA displaying the SVG has the font, or the
> >>    font has exactly the same metric that the one you used to calculate
> >>    the sizes
> >>
> >>    In an ideal world were everyone comply with the latest standard, you
> >>    have a few options:
> >>
> >>    1- Transform the text to shapes
> >>
> >>       The infallible solution
> >>
> >>    2- Make the font available to the browser using a browser supported
> >>    font format
> >>
> >>       Never tried this, but it could work for no complex western
> >>    languages where laying out text hasn't complex rules
> >>
> >>    2- Transform the font to a SVG Font
> >>
> >>       Not all UA/browsers have support for SVG Fonts (Firefox hasn't,
> >>    not sure about Chrome)
> >>
> >>    3- User SVG flow elements
> >>
> >>       Batik has some extensions for this, no standard, SVG 1.2 has
> >>    proposal for that but there isn't any 1.2 compliant browser, and
> >>    Batik isn't 1.2 compliant either
> >>
> >>
> >>        The generated SVG looks like this:
> >>
> >>        <g xmlns="http://www.w3.org/2000/__svg
> >>        <http://www.w3.org/2000/svg>" class="rectangle-node" id="node3"
> >>        transform="translate(200, 225)">
> >>        <rect style=" fill: white;  stroke: black; " width="100.0"
> >>        height="40.0"/>
> >>        <text x="50" font-size="12px" y="20" style=" dominant-baseline:
> >>        central;
> >>        " font-family="helvetica" text-anchor="middle">Stuff</__text>
> >>        </g>
> >>
> >>        As you can see on the attached image this works well with Batik
> >>        (on the
> >>        right of the image) but the same SVG displayed in Chrome (on the
> >>        left)
> >>        is not correct. The text flows out of the rectangle.
> >>
> >>        Why does this calculation is not renderer independent given the
> font
> >>        size and font are specified?
> >>
> >>        What kind of solution can I implement to solve this problem?
> >>
> >>
> >>
> >>
>  ------------------------------__------------------------------__---------
> >>        To unsubscribe, e-mail:
> >>        batik-users-unsubscribe@__xmlgraphics.apache.org
> >>        <mailto:batik-users-unsubscribe@xmlgraphics.apache.org>
> >>        For additional commands, e-mail:
> >>        batik-users-help@xmlgraphics.__apache.org
> >>        <mailto:batik-users-help@xmlgraphics.apache.org>
> >>
> >>
> >>
> >>
>  ------------------------------__------------------------------__---------
> >>    To unsubscribe, e-mail:
> >>    batik-users-unsubscribe@__xmlgraphics.apache.org
> >>    <mailto:batik-users-unsubscribe@xmlgraphics.apache.org>
> >>    For additional commands, e-mail:
> >>    batik-users-help@xmlgraphics.__apache.org
> >>    <mailto:batik-users-help@xmlgraphics.apache.org>
> >>
> >>
> >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: batik-users-unsubscribe@xmlgraphics.apache.org
> > For additional commands, e-mail: batik-users-help@xmlgraphics.apache.org
> >
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: batik-users-unsubscribe@xmlgraphics.apache.org
> For additional commands, e-mail: batik-users-help@xmlgraphics.apache.org
>
>

Mime
View raw message