After an evaluation, GNOME has moved from Bugzilla to GitLab. Learn more about GitLab.
No new issues can be reported in GNOME Bugzilla anymore.
To report an issue in a GNOME project, go to GNOME GitLab.
Do not go to GNOME Gitlab for: Bluefish, Doxygen, GnuCash, GStreamer, java-gnome, LDTP, NetworkManager, Tomboy.
Bug 768118 - Spacing on Paint Dynamics is not working correctly
Spacing on Paint Dynamics is not working correctly
Status: RESOLVED OBSOLETE
Product: GIMP
Classification: Other
Component: General
git master
Other All
: Normal blocker
: 2.10
Assigned To: GIMP Bugs
GIMP Bugs
Depends on:
Blocks:
 
 
Reported: 2016-06-28 00:31 UTC by jose americo gobbo
Modified: 2018-05-24 16:30 UTC
See Also:
GNOME target: ---
GNOME version: ---


Attachments
Drawing Lines with Ctrl+Shift on Paint Tool using spacing of paint dynamics. (101.43 KB, image/jpeg)
2017-04-01 03:19 UTC, jose americo gobbo
Details
Spacing parameter issue drawing freely with a paint tool with spacing tool options > 100% (129.95 KB, image/jpeg)
2017-04-01 03:24 UTC, jose americo gobbo
Details
Drawing Lines with Ctrl+Shift on Paint Tool using spacing of paint dynamics - Tool Options < 100% (114.08 KB, image/jpeg)
2017-04-01 03:25 UTC, jose americo gobbo
Details
Velocity x Spacing Behavior - Paint dynamics (34.02 KB, image/png)
2017-06-02 23:03 UTC, jose americo gobbo
Details
Other Inputs, except velocity that has a different and inverse behavior in relation of others. (33.06 KB, image/png)
2017-06-02 23:12 UTC, jose americo gobbo
Details

Description jose americo gobbo 2016-06-28 00:31:09 UTC
I have made a test with a simple round vbr brush... with only spacing parameter enabled. When the curve is touching the max (top) the spacing is decreasing.

---
Steps:
# Round brush;
# Paint Dynamics with only spacing enabled (is better to use velocity, is more easy to see the behavior);
# Make a constant curve and drop it in the max top: the behavior is as spacing equal to 1.
# Drop the curve to bottom: the behavior is as spacing equal 300 circa.
---
Comment 1 jose americo gobbo 2016-06-28 00:38:36 UTC
(In reply to jose americo gobbo from comment #0)
> I have made a test with a simple round vbr brush... with only spacing
> parameter enabled. When the curve is touching the max (top) the spacing is
> decreasing.
> 
> ---
> Steps:
> # Round brush;
> # Paint Dynamics with only spacing enabled (is better to use velocity, is
> more easy to see the behavior);
> # Make a constant curve and drop it in the max top: the behavior is as
> spacing equal to 1.
> # Drop the curve to bottom: the behavior is as spacing equal 300 circa.
> ---

Identical behavior happens on GIMP 2.8.16.
Comment 2 jose americo gobbo 2016-06-28 00:51:36 UTC
On the GIMP 2.9.4, the Spacing Parameter on Tool Options is not used on Paint Dynamics. 

The idea is that the parameter value of tool options would be the max value on the graph... and the curve would operate between the minimum spacing (1) and max registered in the Tool Options Spacing slider.

The curve on Paint Dynamics works independently, in inverted way and do not is using the Spacing parameter of Tool Options.
Comment 3 Michael Schumacher 2016-07-01 11:18:54 UTC
Confirming.

Changing the velocity/spacing curves to return constant min or max spacing and comparing the actual to the expected results is the most obvious problem.
Comment 4 Michael Natterer 2016-10-30 22:45:42 UTC
Well, when I look at the spacing code in gimp_brush_core_interpolate(),
my brain gets lobotomized instantly. What is this? I have no clue what
it is supposed to do...

We should really fix this for 2.10.
Comment 5 jose americo gobbo 2017-04-01 03:19:24 UTC
Created attachment 349098 [details]
Drawing Lines with Ctrl+Shift on Paint Tool using spacing of paint dynamics.

When we use Ctrl+Shift to draw a line the paint dynamic curve is not applied.
Comment 6 jose americo gobbo 2017-04-01 03:24:10 UTC
Created attachment 349099 [details]
Spacing parameter issue drawing freely with a paint tool with spacing tool options > 100%

When we paint freely with spacing>100% the curves are applied slowly, because the range of spacing is more large.
I think that spacing with spacing more great that 100% no has an effective usage. The current range of spacing on Tool Options is from 0 to 5000%. Is difficult to imagine a case where is necessary spacing so big.
Comment 7 jose americo gobbo 2017-04-01 03:25:54 UTC
Created attachment 349100 [details]
Drawing Lines with Ctrl+Shift on Paint Tool using spacing of paint dynamics - Tool Options < 100%

Fade x Spacing with spacing < 100% is more easy to see the variations and understand the effective usage.
Comment 8 jose americo gobbo 2017-04-01 03:28:36 UTC
T
Comment 9 jose americo gobbo 2017-06-02 23:03:49 UTC
Created attachment 353100 [details]
Velocity x Spacing Behavior - Paint dynamics

I have remade the figures... now is more clear and correct the explanations.
The Velocity is inverted on the curve, this is the minor issue, the range is calculated in a strange way... the MAX is always the double of spacing you chooses on tool options, and the value on tool options is the MIN.
I think what would be correct in these cases is showing in *What I Am Waiting*.
Comment 10 jose americo gobbo 2017-06-02 23:12:00 UTC
Created attachment 353101 [details]
Other Inputs, except velocity that has a different and inverse behavior in relation of others.

The inputs: Pressure, Direction, Tilt, Random and Fade (I don't have conditions to test Wheel), have the same behavior.
The range of the Spacing is positioned of the right-side of MIN value (value choose on tool options), the MAX value is the double of MIN value.
The correct approach, for me, is showed in *What I Am Waiting*.
Comment 11 Jehan 2017-12-04 23:18:41 UTC
Setting to blocker for the release.
Comment 12 GNOME Infrastructure Team 2018-05-24 16:30:09 UTC
-- GitLab Migration Automatic Message --

This bug has been migrated to GNOME's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.gnome.org/GNOME/gimp/issues/923.