[udig-devel] dpi issues

[Vince Darley]

At 15:55 26/03/2008, Jody Garnett wrote:
>I was not aware of that problem; I was generating a PDF myself - I 
>*did* preprocess my map and adjust all the Scales and Font sizes in 
>the GeoTools Style objects (since they are expressed in pixels it 
>needed to be done).
>
>There is a RescaleStyleVisitor documented here:
>- 
>http://docs.codehaus.org/display/GEOTDOC/08+StyleVisitor+use+with+DuplicatingStyleVisitor+and+RescaleStyleVisitor

Ah I'll take a look at that.

>I am not sure how "smart" we want ApplicationGIS.drawMap() to be? 
>Making getDPI available allowed the scalebar

My scalebar does _not_ adjust itself accordingly (recent rc14 nightly 
build).  It just gets progressively smaller and less legible, just 
the same as any other piece of text.

>and other map graphics to know what was going on and adjust 
>accordingly, the BasicFeatureRenderer still made use of the Style as 
>provided (I preprocessed the Style to make it show what I wanted).

Regarding how smart ApplicationGIS.drawMap() should be, I would have 
thought the natural, intuitive thing is for 'dpi' to function how we 
would expect it to function: to control the dpi of the image.  An 
image printed at dpi 144 and resampled to halve the number of pixels 
should look largely identical to an image printed at dpi 72.  That's 
what dpi means, after all.  Instead we have a situation where the 
labels, scale, etc, shrink.

cheers,

Vince.