[GRASS-dev] things to do before the 6.3.0 release

Glynn Clements glynn at gclements.plus.com
Wed Dec 19 18:28:51 EST 2007

Hamish wrote:

> > > next problem- r,d inverse fill a small bay upon zoom in.
> > > Also, "l" in XDRIVER fill is badly broken. "g" is correct in all
> > > cases. (the vector map for that section of coastline available upon
> > > request)
> > > http://bambi.otago.ac.nz/hamish/grass/bugs/d.vect/dec2008/dvect_render_fill_Xdriver.png
> > > http://bambi.otago.ac.nz/hamish/grass/bugs/d.vect/dec2008/dvect_render_fill_PNGdriver.png
> > 
> > Please specify the region, so that I can attempt to reproduce this.
> Ok, I'll have to crop out that bit of my coastline map for you.
> (cropping made the problem go away, I'll send you the full map off-list)

Duh; I spent about two hours looking over the culling algorithm before
noticing that the problem with "l" is due to overflowing X's
16-coordinate range (16-bit signed short: -32768 to 32767).

That issue effectively rules out using "l" so long as XDRIVER exists. 
I'll leave the code there for 7.x.

I can't reproduce the inversion with r/d and the PNG driver (using r/d
with XDRIVER kills Cygwin's X server), but it might be sensitive to
the region. Can you provide a region where this occurs?

> > > > g should only be used if none of the others can be made to work.
> > > 
> > > currently 'g' is still the only one that works properly in all cases
> > > for both XDRIVER and PNG driver.
> ..
> > > Do you have any objections to using "g" as the default for the 6.3.0
> > > release? (and leaving as-is [a work in progress] in 6.3.cvs)
> > 
> > Yes, as it only works with the raster drivers (and may not work right
> > with the cairo driver if using anti-aliasing).
> how about 'c' as the default for the 6.3.0 release then?
> (if PNG driver boundary/fill line-up problem can be fixed)

It looks like it's going to have to be "c". r, d and l all risk
passing out-of-range coordinates to XDRIVER, which will produce
complete garbage and may even kill the X server.

Glynn Clements <glynn at gclements.plus.com>

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