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

Steve Lime steve.lime at DNR.STATE.MN.US
Mon Jan 2 23:16:51 EST 2006

Paul (et al.): I've played around with these a ton recently. I did change the brush creation algorithm to more closely approximate Photoshop or Gimp and the brushes look quite nice. The stair steps still persist at some angles. I'm convinced it is a problem in GD. Brushes w/alpha transparency seem to suffer from aggregation effects of repeated alpha blending. For example, you can create a  circular brush with alpha=64 (50% transparent) and if you draw with it the resulting line is *much* darker than you would expect. This has an unfuzzing effect. As as result the "jaggies" you see in unantialiased lines persist. Off to poke around in GD now.

A work in progress...


>>> Paul Spencer <pspencer at DMSOLUTIONS.CA> 12/22/05 6:54 AM >>>

I have a question about fuzzy brushes.  Your test case looks really  
good.  We tried this on our tiger map file in ka-Map and the results  
are less impressive.  It seems to work well for lines that are close  
to 45 degrees, but for lines that are closer to the vertical or  
horizontal, there is still a noticeable stairstep effect.  Did you  
try other angles on the line?  From what you said, my understanding  
is that this could be affected by the default hardness that you have  



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  
> good to go? Did you still have work to do on the fuzzy brushes Steve?
> Daniel
> -- 
> ------------------------------------------------------------
>  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/|

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