(08-21-2021, 04:35 AM)PixLab Wrote: Here is the brush, there is no other colors, than white, red, green.



Load it as an image in GIMP
Ctrl + A then Ctrl + C
Create new doc then Select that brush (Clipboard Image, first in the brush list)
Spacing 1
Force 70


Make a square....
do you got some black stripes?

Even worse...
Try Dynamics / Untitled >  Edit dynamics check "angle with Fade"


Fade length ~100
Repeat > Sawtooth wave (or any repeat will do)


Make a square...
Is it only me getting those black things?



So I tried to save it as a brush.gbr and put it in the brushes folder => same things happening
I tried also to select without feather =0 > shrink 3 pixels
same thing is happening but sharper....
And if you change the size of the brush (like smaller) it's even worse than above

Patterns that I saw (it's more obvious with dynamics):
drawing right to left is better (less black)
drawing bottom to top is better (less black)
drawing left to right is the worst
drawing top to bottom is the worst as well
reducing Force below 30 have a better effect, (less black parasites) but the candy alike is not sharp enough anymore > and goes on the blur side...

I'm getting out of ideas...
buntu 20.04, GIMP 2.10.24/25 PPA/appimage
did try also on my kid computer > MX Linux 19.4 GIMP from the original repo (Debian) 2.10.24, same problem

(08-21-2021, 12:56 PM)programmer_ceds Wrote: Not quite as dramatic as you describe but the dithered pixels around the edge of the circle are causing streaks of colours that are not the pure white, green and red of the png file when I draw with it as the brush. Could these pixels be connected with the problem?

(08-22-2021, 03:08 AM)PixLab Wrote:

(08-21-2021, 12:56 PM)programmer_ceds Wrote: Not quite as dramatic as you describe but the dithered pixels around the edge of the circle are causing streaks of colours that are not the pure white, green and red of the png file when I draw with it as the brush. Could these pixels be connected with the problem?

Thanks to had a look at it.
Did you got the same on Windows? If so, do you think it's a bug?

(08-22-2021, 07:48 AM)programmer_ceds Wrote: What I was seeing was caused, I think, by the pixels that were not solid colour. You could use a 1 pixel hard brush with the pencil to make these pixels either solid white, green or red and then see what happens.

(08-21-2021, 04:35 AM)PixLab Wrote: I tried also to select without feather =0 > shrink 3 pixels
same thing is happening but sharper...

(08-23-2021, 03:02 PM)rich2005 Wrote: I think it is this bug: https://gitlab.gnome.org/GNOME/gimp/-/issues/5509

Rotating the brush introduces (semi-)transparent pixels, which show black especially over the white quarters.

I tried all ways, hard edge brush, anti-aliased brush, all the precisions, all the modes, without success.