Antialiasing on Paintbrush calculates always with black

[Martin Naewe]

Tested on master branch:

When using a white (ore any other color) paintbrush with size > 1, antialiasing pixels comes up in a mix of the used color and black, resulting in grey pixels.

It looks like a dark wrapper around the line instead of a fading.

[Cameron White (cameronwhite91)]

It looks OK to me - what operating system, GTK# version, etc are you using?

[Martin Naewe (martin-naewe)]

I checked again. It happends when using a second layer.
Just make a second layer, use a big white brush and draw in that transparent layer.

I have here a VM with Ubuntu 12.04 64bit, just installed Mono from Software Center (2.8.6.3+dfsg-2)

[Martin Naewe (martin-naewe)]

Possibly, the blur effects are affected as well.

[fredrik lundin (flurick)]

This seems to be because transparent layers are set to color 0,0,0,0 (rgba) fading from any color to that will make it go trough grey, because 0,0,0 (rgb) is black. One possible workaround is to fill the transparent layer with a zero alpha white 255,255,255,0 (rgba), note that painting dark colors would then make them "glow" instead.

Maybe cairo can handle all that with the CAIRO_ANTIALIAS_BEST ?
http://www.cairographics.org/manual/cairo-cairo-t.html#cairo-antialias-t

[Cameron White (cameronwhite91)]

This seems to have been fixed by https://github.com/PintaProject/Pinta/pull/98