Date: Tue, 18 Sep 2012 21:02:56 +0200 From: scl.gplus@gmail.com
To: gimp-user-list@gnome.org
Subject: [Gimp-user] How to draw with pressure dependend brush size

BTW is there a need to ship these Paint dynamics settings with GIMP?

Kind regards,

Sven

[1] https://bugzilla.gnome.org/show_bug.cgi?id=682351 [2]
https://mail.gnome.org/archives/gimp-user-list/2012-September/msg00212.html _______________________________________________ gimp-user-list mailing list
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I thought a straight size-pressure mapping was one of the defaults shipped with GIMP? (Apparently it's not!)

Size/opacity and hardness/opacity are two of THE simplest, most basic tablet mappings you can have; they should seriously be part of the default package. Why we should have one for inverted size/pressure but not straight size/pressure ... that's snafu to me.

-- Stratadrake strata_ranger@hotmail.com
--------------------
Numbers may not lie, but neither do they tell the whole truth.

I thought a straight size-pressure mapping was one of the defaults shipped with GIMP? (Apparently it's not!)

Size/opacity and hardness/opacity are two of THE simplest, most basic tablet mappings you can have; they should seriously be part of the default package. Why we should have one for inverted size/pressure but not straight size/pressure ... that's snafu to me.

Basic Paint Dynamics maps pressure with opacity and size with velocity, which is quite natural.

Hi,

On Wed, Sep 19, 2012 at 4:02 AM, scl wrote:

Hi,

there was a question in Bugzilla [1] that is better discussed here.

Problem: A user wants to draw with the pencil or the ink tool using a tablet. The brush size should increase with the pressure: low pressure should result in a small brush size, high pressure result in a bigger brush size.

Solution:
1. Make sure GIMP recognizes tablet pressure. You find some useful information in the thread [2] a few days ago, especially the posting of Jehan Pagès (thanks Jehan ;-) ).

No prob. I know this is quite a typical problem that a lot of people encounters (cf. all the forums, blog posts, etc. where people encoutered this ). I even think that this configuration of tablet should be a default (then power-users may change the settings later, but at least one-time users have a good experience with a suitable tablet pressure).

I am actually not a graphist myself, rather a developer, but I am currently working with one, and we are trying to get to a full free-software stack. I will probably make a blog post later to details all the process and all the tricks I learned from various people. :-)

2. in the Windows menu select 'Dockable Dialogs', then 'Paint Dynamics'. The 'Paint dynamics' dockable will open. 3. In the 'Paint dynamics' dockable list select 'Negative size pressure'. Right click on it, select 'Duplicate dynamics'. A copy of this dynamics will be created and opened in the 'Paint Dynamics Editor' dockable. 4. In the 'Paint Dynamics Editor' there's a textbox for the name of the Dynamics at the top. Enter a meaningful name, like 'Positive size pressure'. 5. Below that textbox is a listbox at the top. Choose 'Size'. This will show a diagram, showing the effect of the pressure on the brush size. Drag the ends of the descending red line to match the ascending gray line.

I don't really understand here. Seems like very close to "Pencil Generic" which is the default dynamics, isn't it? I mean, "Pencil Generic" has a slightly different curve (not straight proportional), but opacity also increases with pressure, as well as size.

I don't say this new dynamics is worst or better. I guess only a graphist having to use it daily could say which one feels nicer/more realistic/comfortable. I simply don't understand why you seem to say that this is *completely* different from the current default:

The brush size should increase with the pressure: low pressure should result in a small brush size, high pressure result in a bigger brush size.

For me this is exactly what I got by defaults with "Pencil Generic". Maybe there is something I did not understand in your new dynamics?

6. Save the settings for this Paint Dynamics. 7. In the Paint tool (Pencil, Paintbrush, Airbrush, etc). choose your new Paint Dynamics and start painting.

About this, I have a comment. I think graphists don't see it because they (you?) do everything with their tablet. But as I was using the mouse to change the pen features, then trying to draw with the pen, I had a hard time figuring out why my settings were never applied to my drawing.
Then I understood that Gimp actually records separate features for each pen/tablet/mouse. So if you choose a tool, a brush, and customize it with your mouse, then choose another tool, brush, other customization with your tablet pen, you can use both of them by just switching mouse and pen without touching the menu. Even better: if you plug 2 tablets, you can use different tools on each (actually tested and working!). What I would love to test is 2 pens for the same tablet: will Gimp make the difference and record different settings for each pen (we have 2 tablets, but unfortunately pens on each are not compatible, so I can't test)? That would be awesome.

I know you can easily switch tools with shortcuts and save and load tool settings (though I have not found if there was a way to assign shortcuts to a specific settings, let's say one you often switch to. If someone has a hint...), so maybe it is not that helpful. But maybe being able to replace these by switching pens physically, more like a common non-digital workflow, may be interesting as well for some people (I guess).

Thanks!

Jehan

I hope this helps.
BTW is there a need to ship these Paint dynamics settings with GIMP?

Kind regards,

Sven

[1] https://bugzilla.gnome.org/show_bug.cgi?id=682351 [2]
https://mail.gnome.org/archives/gimp-user-list/2012-September/msg00212.html _______________________________________________ gimp-user-list mailing list
gimp-user-list@gnome.org
https://mail.gnome.org/mailman/listinfo/gimp-user-list

I think I screwed up my phrasing back there. Sure, there's "Basic Dynamics" (pressure/opacity with fade-in, velocity/hardness) and "Basic Simple" (pressure/opacity and ... how exactly does this one differ from "Pressure Opacity"?), but I meant to say that there are no basic pressure/size and pressure/hardness dynamics in the default package, when there should be.

(BTW, the "Basic Simple" and "Pressure Opacity" dynamics files, possibly others, seem to have a lot of redundant points in their curve definitions. I also find it ironic that the "Basic Dynamics" file, which has slightly more mappings, doesn't use any curve definitions at all.)

-- Stratadrake strata_ranger@hotmail.com
--------------------
Numbers may not lie, but neither do they tell the whole truth.

From: olecarme@gmail.com Date: Wed, 19 Sep 2012 19:38:00 +0200 Subject: Re: [Gimp-user] How to draw with pressure dependend brush size To: strata_ranger@hotmail.com
CC: scl.gplus@gmail.com; gimp-user-list@gnome.org

I thought a straight size-pressure mapping was one of the defaults shipped with GIMP? (Apparently it's not!)

Size/opacity and hardness/opacity are two of THE simplest, most basic tablet mappings you can have; they should seriously be part of the default package. Why we should have one for inverted size/pressure but not straight size/pressure ... that's snafu to me.

Basic Paint Dynamics maps pressure with opacity and size with velocity, which is quite natural.

Olivier Lecarme