Indeed, this is a wish for many of us. You can fake it in the meantime with 3rd party applications that overlay rulers on the screen. This is, of course, never as svelte as an in-built solution.
On mac I’ve used one called “Red Lines Tool” but it hasn’t been updated in 2 years and is a little finicky at times. There’s another that is similar (but newer) that I’ve just downloaded to test called “SmartGuide - Screen Guide”.
EDIT: as a follow up, I really like “Smart Guide”. It’s very simple to use, and the lines you can place on screen are selectable when you are in other programs. (This can be a pro or a con. I just know in my “red lines” tool they were totally inert unless you changed back to that program, whereas with smart guide you can click on it, and drag it (although you then have to make Dorico the program in “focus” after that. But it’s very svelte and simple, and it only costs $2.99.
A nice Shareware tool for Windows is PicPick, which besides the Ruler also includes Screen Capture, Color picker, Magnifier, Protactor, Crosshair and other useful things.
I’ve being using Free Ruler, an app which I downloaded from the Mac App Store about a year ago. If I remember right, someone recommended it on here! I’ve also found it useful in other programs.
I couldn’t live without XScope, but I never use its rulers feature with Dorico! As a tool for people working on the development of graphical user interfaces, however, it’s invaluable. Probably overkill for this particular use case, though.
Thanks for all the recommendations of 3rd party apps. I’m fully submerged in the Apple eco system, but I still appreciate the suggestions for Windows applications.
For me, rulers are essential in a music notation program. Not only for ‘melodramas’ (see example), but also to quickly check graphical elements more efficiently.
Is it possible to hope for rulers in Dorico at some point? In Finale, I valued and frequently used this feature, especially with the snapping function