Re: Limitation of recording surface

Adrian Johnson <[email protected]>
Newsgroups gmane.comp.lib.cairo
Message-ID <[email protected]>
On 04/02/15 20:05, Bernhard R. Fischer wrote:
> Hi!
> 
> I'm developing Smrender which is a chart renderer for OSM data and I use 
> cairographics for it. Those charts are highly complex and contain a huge 
> amount of vector data.
> 
> Internally, everything is rendered to a recording surface which is finally 
> "painted" to a PDF surface (or other formats).
> 
> 
> I found out that with some amount of input data the PDF is degraded to a 
> raster image instead of vector image.
> 
> Is there any known limit in the recording surface or in the PDF surface which 
> causes this behavior? Is there any possibility to change this or do you have 
> any suggestions what I can do to avoid this?

No. As long you do not use operators unsupported by PDF it should not be
rasterized. If you are only using CAIRO_OPERATOR_OVER and seeing
rasterization in pdf it is likely a bug.


> 
> Examples:
> The following two charts are rendered on the same system, same software, same 
> version...
> The only difference is that for the 2nd (raster) PDF more input data (contour 
> lines) is used. You can clearly see (if you zoom in) that the first one is a 
> vector image and the second is a raster image. The first also has embedded 
> fonts which the 2nd does not have.
> 
> http://www.abenteuerland.at/download/eagle/murter_vector.pdf
> http://www.abenteuerland.at/download/eagle/murter_raster.pdf
> 
> 
> Best regards,
> Bernhard
> 
> 
> 

-- 
cairo mailing list
[email protected]
http://lists.cairographics.org/mailman/listinfo/cairo
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.