Re: [Gimp-developer] Bug 719435

[Ofnuts <ofnuts laposte net>]

On 12/02/2013 01:10 AM, Rick C. Hodgin wrote:
> On 12/01/2013 12:15 PM, Ofnuts wrote:
> > On 11/30/2013 10:53 PM, Hodgin, Rick C. wrote:
> > > I was asked by Michael Natterer to discuss this enhancement on the 
> > > GIMP developer list.
> > > https://bugzilla.gnome.org/show_bug.cgi?id=719435
> > >
> > > Basically, I'd like to see the line cue for the Pen tool colorized 
> > > when either of the two X,Y axis offsets are 0, or when their 
> > > absolute values are equal (or have it match the existing angles used 
> > > for snapping, though I personally only use the 45 degree angle 
> > > setting often).
> > >
> > > This colorization cue would be visible without activating snapping, 
> > > and would simply change the line color when those conditions are met.
> > >
> > > I have no other reason for wanting it except that I think it is 
> > > difficult to see when the line is at exactly 45 degrees since it 
> > > uses such a smooth anti-aliasing algorithm, and that it would 
> > > provide added value, be a nice helpful feature, and something that 
> > > I've wanted in GIMP for quite some time. :-)
> >
> > How would that be better than the current "constrained angles"?
>
> It would cue automatically without constraining.  As the cursor moves 
> around, the colors would indicate alignments.  It could be used to 
> examine existing image content, or to help align new.

First,  unless we introduce some error margin the cue could be rather 
elusive because you would have to be on the right pixel (and stay there).

Second, I don't see the logic of checking if you are at 45° and not draw 
the line in a paint tool. If you want to check alignments, the right 
tool would be the Measure tool. Having display changes (color or else, 
there are color-blind users) on some angles (and perhaps distances) 
could be useful there (one more Tool option, and with the caveat about 
elusiveness). And as a reminder, the Measure tool also has constrained 
angles (so you can move the second measure point along an accurate 
vertical/horizontal/diagonal), and will let you to position H/V/H+V 
guides where the cursor is. So using both capabilities together you can 
easily define some point at 45° from an existing point(*)

(*) Note to the devs: Currently using the constrained angles disables 
snapping to guides and path.  Having both together would be useful: draw 
the perpendicular to a line through a given point, etc...