Often during the layout process Dorico will, for some reason, not fill out a page, even though there’s plenty of room for another system and the vertical layout settings are such that the next system should indeed be included in the frame. I have to fill out the page manually, meaning sometimes that I might have to continue doing this for several pages after which, suddenly, Dorico starts filling out the pages predictably again. This is even though there are no frame or system breaks. What bothers me is that I can’t see any pattern to this behaviour. There’s no point in posting a document here, as this happens with pretty much all documents, regardless of my layout settings. What am I missing?
You might not be missing anything. Sometimes this happens to me as well. It’s easily resolved by adding frame breaks and setting “wait for next frame break.”
Do you have rehearsal marks or text items in the systems in question? I know there’s been discussion about certain items above the staff that seem to require too much vertical space.
Have you checked your ideal inter-system gap? That can sometimes be the culprit.
Have a look at the distance values in Engrave Mode > Staff Spacing, to see if anything looks suspicious.
For a ‘thick’ layout, I tend to reduce the Vertical gap settings to very small values, safe in the knowledge that Dorico won’t crash things together.
This is the flip side of the issue described here. Just as sometimes Dorico cannot determine whether a frame will be too full, sometimes it cannot determine whether the frame will be too empty.