Re: [Gimp-developer] Feature suggestion: Gimp aspect ration based on golden rule

[Ofnuts <ofnuts gmx com>]

On 16/06/15 23:14, Tim wrote:
> Hi folks,
>
> first of all i would like to thank you undiscribable much for that grate
> image manipulating tool which was so good that a whole user environment
> was build onto its toolkit...
>
> I just have a some feature suggestion that i would consider as nice to have.
>
> In gimp it is possible to select a rectangle area fixed to an aspect
> ration of the users choice. Here in Germany we have got some paper
> formats after the so called "DIN A" norm (DIN A4 is the most popular
> one)[01] which aspect ration is based on the golden rule (1 to the
> square root of 2).
>
> It would be nice if there would be a feature for that, like as i
> discribed in the attached screenshot.
>
> I refer fo comments bout this with this...

The "Golden Rule" isn't about sqrt(2). The golden rule us about 
(sqrt(5)+1)/2 (~=1.618034, aka "Phi") which has the nice property that 
1/Phi==Phi-1. Sqrt(2) is just the form factor that remains constant when 
you fold/cut a rectangle in half across the longest side which is why it 
has been chosen for paper formats.

Besides 1.618:1 and 1.4142:1, there are plenty of notable aspect ratios: 
photographers use 3:2 (DSLRs) or 4:3 (compact cameras) as well as 
various wide-screen formats (16:10, 16:9), there is also obviously a 
case for 1:1...

In practice if you have a fetish for some specific ratio, set it in the 
tool (Rectangle Select or Crop), and use the small diskette icon at the 
bottom of the Tool options to save it as a preset (you can even give it 
an icon). Then in one click on the load preset icon you can restore the 
aspect ratio, the "Keep aspect ratio" checkbox, and any other mundane 
setting (origin, centering, etc...).