Fuzzy brushes (was "Ready for 4.8.0-rc1?")

[Sean Gillies]

Steve,

I just checked again with one of my mapfiles. I have a graticule  
shapefile as a line type layer, ANTIALIASING TRUE and symbol 0 in the  
style, but no sign of antialiasing happening. Is there more to it  
than that?

Sean

On Jan 3, 2006, at 8:21 AM, Steve Lime wrote:

> Try it now. I had a small problem with the trivial (1 pixel wide)  
> case and =
> antialiasing. My test cases run fine now. This should be enough to  
> get =
> single pixel aa lines:
>
> STYLE
>   COLOR r g b
>   ANTIALIAS TRUE
> END
>
> Steve
>
>>>> Sean Gillies <sgillies at FRII.COM> 01/02/06 11:35 PM >>>
> Steve,
>
> What about 1-pixel wide antialiases lines? I was trying that out  
> last =20
> night, but didn't see any effect. Do we have to have width > 2 to  
> get =20
> antialiasing?
>
> Sean
>
> On Jan 2, 2006, at 9:16 PM, Steve Lime wrote:
>
>> Paul (et al.): I've played around with these a ton recently. I did  
>> =20
>> change =3D
>> the brush creation algorithm to more closely approximate Photoshop  
>> =20
>> or Gimp =3D
>> and the brushes look quite nice. The stair steps still persist at =20
>> some =3D
>> angles. I'm convinced it is a problem in GD. Brushes w/alpha =20
>> transparency =3D
>> seem to suffer from aggregation effects of repeated alpha  
>> blending. =20
>> For =3D
>> example, you can create a  circular brush with alpha=3D3D64 (50% =20
>> transparent)=3D
>>  and if you draw with it the resulting line is *much* darker than =20
>> you =3D
>> would expect. This has an unfuzzing effect. As as result the =20
>> "jaggies" you =3D
>> see in unantialiased lines persist. Off to poke around in GD now.
>>
>> A work in progress...
>>
>> Steve
>>
>>>>> Paul Spencer <pspencer at DMSOLUTIONS.CA> 12/22/05 6:54 AM >>>
>> Steve,
>>
>> I have a question about fuzzy brushes.  Your test case looks  
>> really =20
>> =3D20
>> good.  We tried this on our tiger map file in ka-Map and the =20
>> results =3D20
>> are less impressive.  It seems to work well for lines that are =20
>> close =3D20
>> to 45 degrees, but for lines that are closer to the vertical or =3D20
>> horizontal, there is still a noticeable stairstep effect.  Did you  
>> =3D20
>> try other angles on the line?  From what you said, my  
>> understanding =20
>> =3D20
>> is that this could be affected by the default hardness that you =20
>> have =3D20
>> chosen?
>>
>> Cheers
>>
>> Paul
>>
>> On 22-Dec-05, at 12:08 AM, Daniel Morissette wrote:
>>
>>> Our planned date for 4.8.0rc1 is today (Thursday Dec 22nd). Are  
>>> we =20
>>> =3D20
>>> good to go? Did you still have work to do on the fuzzy brushes  
>>> Steve?
>>>
>>> Daniel
>>> --=3D20
>>> ------------------------------------------------------------
>>>  Daniel Morissette               dmorissette at dmsolutions.ca
>>>  DM Solutions Group              http://www.dmsolutions.ca/
>>> ------------------------------------------------------------
>>>
>>
>> +-----------------------------------------------------------------+
>> |Paul Spencer                           pspencer at dmsolutions.ca   |
>> +-----------------------------------------------------------------+
>> |Applications & Software Development                              |
>> |DM Solutions Group Inc                 http://www.dmsolutions.ca/|
>> +-----------------------------------------------------------------+
>
> ---
> Sean Gillies
> sgillies at frii dot com
> http://zcologia.com/news