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

Glynn Clements glynn at gclements.plus.com
Mon Dec 3 04:12:30 EST 2007

Glynn Clements wrote:

> > next problem- in the PNG driver for all rendering methods but "g" the
> > boundaries and fills don't line up. It's obvious if you look with xmag.
> >  http://bambi.otago.ac.nz/hamish/grass/bugs/d.vect/dec2008/dvect_render_C_and_all_but_G_xmag_PNGdriver.png
> >  http://bambi.otago.ac.nz/hamish/grass/bugs/d.vect/dec2008/dvect_render_fill_PNGdriver.png
> Okay, I think I know about this. Points and line vertices need to use
> floor(), while polygon vertices need round().


> > and finally- "c" still has 1 pixel of white at the top and bottom of the
> > display:
> >  http://bambi.otago.ac.nz/hamish/grass/bugs/d.vect/
> I'll look into this later.

This was caused by adding a clip margin so that thick lines didn't
extend outside of the clip region.

In retrospect, this was a mistake. That kind of clipping should be
left to the driver's clipping.

I have removed the clip margin.

> > > To get rid of the problem with render=l drawing beyond the edge of the
> > > region, d.vect needs to set the raster clip window (R_set_window()) to
> > > match the region (D_setup() sets it to match the frame), but it needs
> > > to be set back afterwards (D_setup(0) should suffice).
> > 
> > Should we wait to know if "l" will be the default before adding that?
> I would recommend using l as the default, as it should be the fastest.
> [Actually, I also need to add code to remove 0-length segments. When
> zooming in, there could be a lot of these.]

I have added code to remove zero-length segments.

Glynn Clements <glynn at gclements.plus.com>

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