Rendering problems with thin borders

["John C. Turnbull" <oz...@ozemail.com.au>]

I have a number of SVGs which feature graphics with thin borders.  The
problem is that with Batik when it renders those SVGs at smaller sizes, it
tends to not display all or parts of the border at all.

 

How difficult would it be to modify Batik so that it never fails to render
something because it becomes "too thin" but rather renders it with a higher
alpha value instead to give the illusion of thinness at smaller scales?

 

Thanks,

 

John

RE: Rendering problems with thin borders

["John C. Turnbull" <oz...@ozemail.com.au>]

Hi Thomas,

 

I am finding that for some of the SVGs I am working with it is sufficient to
modify the stroke as you suggested but for many of them they are rendering
obscure shapes and the stroke painter is not invoked.

 

I take it that when you say "writing a new rasterizer" we are not talking
about a trivial task?  Well, it would be so nice if I could somehow do that
as I really want to be able to zoom out on these SVGs without their borders
disappearing at smaller scales.  Can it be done?  I am willing to put in the
effort if it's really feasible.

 

Thanks,

 

John

 

From: thomas.deweese@kodak.com [mailto:thomas.deweese@kodak.com] 
Sent: Sunday, 4 January 2009 01:29
To: batik-users@xmlgraphics.apache.org
Cc: batik-users@xmlgraphics.apache.org
Subject: Re: Rendering problems with thin borders

 


Hi John,

"John C. Turnbull" <oz...@ozemail.com.au> wrote on 12/31/2008 10:33:46 PM:

> I have a number of SVGs which feature graphics with thin borders.  
> The problem is that with Batik when it renders those SVGs at smaller
> sizes, it tends to not display all or parts of the border at all. 
>   
> How difficult would it be to modify Batik so that it never fails to 
> render something because it becomes "too thin" but rather renders it
> with a higher alpha value instead to give the illusion of thinness 
> at smaller scales? 

   As long as we are talking about true SVG strokes it might be 
possible by adjusting batik.gvt.StrokingShapePainter so that it 
checks the screen stroke width in it's paint method and then 
replace the 'real' stroke with a wider stroke to maintain some 
minimal stroke width (say .5 screen pixel or something). 

   If the SVG content actually draws the thin lines as shapes 
then detecting/fixing these would effectively require writing 
a new rasterizer. 

Re: Rendering problems with thin borders

[th...@kodak.com]

Hi John,

"John C. Turnbull" <oz...@ozemail.com.au> wrote on 12/31/2008 10:33:46 
PM:

> I have a number of SVGs which feature graphics with thin borders. 
> The problem is that with Batik when it renders those SVGs at smaller
> sizes, it tends to not display all or parts of the border at all.
> 
> How difficult would it be to modify Batik so that it never fails to 
> render something because it becomes ?too thin? but rather renders it
> with a higher alpha value instead to give the illusion of thinness 
> at smaller scales?

   As long as we are talking about true SVG strokes it might be
possible by adjusting batik.gvt.StrokingShapePainter so that it
checks the screen stroke width in it's paint method and then
replace the 'real' stroke with a wider stroke to maintain some
minimal stroke width (say .5 screen pixel or something).

   If the SVG content actually draws the thin lines as shapes
then detecting/fixing these would effectively require writing 
a new rasterizer.