Re: spurious lines in gs with antialiasing

[Theo H. <th...@ph...>]

Hans-Bernhard Broeker wrote:
> Petr Mikulik wrote:
> 
>> Well, it looks to me that it must be a bug in ghostscript -- some 
>> rounding of positions or whatever. Below is a simplest postscript code 
>> that demonstrates spurious lines in a pm3d-like image:
> 
> 
> I don't fully agree that those lines are "spurious".  Since you only
> fill-ed the paths, but didn't stroke them, there are technically
> gaps of zero pixel width between adjacent tiles.  And just like lines of 
> width zero are not exactly the same thing as no lines at all, gaps of 
> width zero are not the same as no gap at all.  For this to be a 
> meaningful test, the paths could have to be both filled and stroked.

I just tried this. Fill-ing and stroke-ing gives much better results: 
the lines occur less frequently, and with less intensity. It seems to me 
that if filled polygons were stroke-d with a line width just slightly 
over the nominal value, the anti-aliasing problem with Ghostscript could 
be worked around. Unfortunately, I don't know enough Postscript to be 
able to test this.

THeo