GNOME Bugzilla – Bug 748060
Force parameter on Tool Options is ignored when there is dynamics force
Last modified: 2016-11-27 16:34:21 UTC
Created attachment 301850 [details] Force Parameter and ranges with a simple paint dynamic I've some tests and it seems that the Force parameter on Tool Options is not working... I tested with a simple paint dynamic with opacity and force enabled (all linear curves)... with zero, 50 and 100 on Force parameter of the Tool Options... and the aspect of stroke is the same... for me is not possible see great differences.
The dynamic force takes precedence over the tool options force. This seems to be intended, but the UI doesn't suggest this in any way.
For example, in the current git master, the behaviour to Hardness on Tool Options is: Paint dynamic with 'Off' the parameter, the Tool Options hardness cursor works alone (over a linear curve, perhaps); Paint dynamic parameter 'On'... => imply a curve, the cursor of Hardness on Tool Options has an attenuation function over the paint dynamics Hardness curve. With Force parameter on Tool Options UI happens as follow: Paint dynamic parameter 'Off', the cursor don't make any transformation or gain in the brush; Paint dynamic parameter 'On', only the curve works... the cursor of Force on Tool Options, don't make anything too. Many parameters on Tool Options UI have an hybrid relationship with paint dynamics... Someone work alone, others alone and together, others only together with a dynamics. + The first case, only alone, are: Aspect Ratio, Spacing, Smooth stroke, Incremental (boolean, perhaps). + Second case(alone and together de paint dynamics), are : Opacity, Size, Angle, Hardness, Force (in theory ;) and Jitter. The third case [+]Dynamic Options on Tool Options UI: It depends of the tool but we can the max of two parameters, the Fade and the Color. In resume, for me, the Force, in the current status, don't make part of any of three cases.
> + The first case, only alone, are: Aspect Ratio, Spacing, Smooth stroke, > Incremental (boolean, perhaps). I intend 'alone' => always without dynamics.
> With Force parameter on Tool Options UI happens as follow: > Paint dynamic parameter 'Off', the cursor don't make any transformation or > gain in the brush; > Paint dynamic parameter 'On', only the curve works... the cursor of Force on > Tool Options, don't make anything too. I've supposed here that the Force parameter is a kind of gain factor to amplify any curve 'on' the dynamics, for example, if you've Opacity(pressure)... the parameter Force will amplifies my opacity with gain factor obtained on Force(pressure) curve.
(In reply to jose americo gobbo from comment #4) > > With Force parameter on Tool Options UI happens as follow: > > Paint dynamic parameter 'Off', the cursor don't make any transformation or > > gain in the brush; > > Paint dynamic parameter 'On', only the curve works... the cursor of Force on > > Tool Options, don't make anything too. > > I've supposed here that the Force parameter is a kind of gain factor to > amplify any curve 'on' the dynamics, for example, if you've > Opacity(pressure)... the parameter Force will amplifies my opacity with gain > factor obtained on Force(pressure) curve. I've a short video to illustrate this case in particular... the link: https://www.youtube.com/watch?v=qvS614DFR4k
*** Bug 741772 has been marked as a duplicate of this bug. ***
Yes, the relation between tool options values and dynamics is mostly unclear without reading the code, and even then it's not very obvious, this needs to be fixed/clarified.
The Hardness do not working too.
(In reply to jose americo gobbo from comment #8) > The Hardness do not working too. In the last GIT Master commit bb4f42f, the Hardness is working normally.
In the last GIT Master commit d51de65, the Force Parameter is working normally. Perhaps the fix on the https://bugzilla.gnome.org/show_bug.cgi?id=761880 > Paint Dynamics Editor's Mapping Matrix distorted by labels, has contribute to fix this bug too.
In the GIT Master commit 4df9a1d, the Force Parameter on Tool Options is working only together a paint dynamic curve on. I understand that Force slider must work also independently, if we have enabled a curve for this or not on paint dynamics editor.
(In reply to jose americo gobbo from comment #11) > In the GIT Master commit 4df9a1d, the Force Parameter on Tool Options is > working only together a paint dynamic curve on. I understand that Force > slider must work also independently, if we have enabled a curve for this or > not on paint dynamics editor. Using the paintbrush tool with brush 'Hardness 025', size 51, Dynamics Off and foreground color red. Strokes on a white layer with Force 5, 10, 15 are clearly different. Increasing more the force reaches soon the saturation. I think the effect of the force parameter is not much noticeable because in a 8bit world brushes are designed to be rather attenuated than amplified and so unless you use brushes with many low values you can't see its effect because it is capped. Probably this feature was designed to be used with floating point brush masks, painting on a floating point layer, so not limited by the max value representable (255), (pressurizing the mask now is done in 8 bit though).
I have made a test with GIMP Git Master commit 6fe900f. The bug is not present in this commit... apparently now is OK!
Created attachment 335468 [details] Force Parameter on Tool Options - test with off paint dynamic, 8bit and 16bit images