A short slur mid-thickness doesn't match tie mid-thickness.

• Sep 24, 2014 - 11:52
S4 - Minor

There's a strange behavior where slur mid-thickness seem to be thinner when the slur is short. This doesn't happen organically or smoothly but in a sort of snappy, one-or-the-other way. Also, it is at odds with tie thickness, which seems to have a different behavior.

See this screenshot...


MuseScore file attached.

This is 2.0 beta and seems to affect all platforms.

More here: http://musescore.org/en/node/34176 , with animated gifs and additional screenshots.

Attachment Size
slur-thickness-vs-tie.mscz 1.87 KB
slur-thickness-vs-tie.png 161.76 KB


Just looking at that picture, I see it's not totally obvious, depending on your screen quality/resolution, so please click for full size.

Basically, though...
bar 1 seems good... the slur and tie complement eachother, in terms of thickness.
bar 2 the shorter slur is too thin
bar 3 the first slur is nice and thick, the second slur is unacceptably thin, and then the last tie (despite being shortest), is nice and thick again.

As discussed in the forum thread, the relevant code is here:


This is where the thinning happens. On the surface without actually understanding the math, dividing by spatium and then comparing spatium seems strange to me. We're basically comapring something against spatium squared. If I remove the division by spatium, then the thinning only occurs for extremely short slurs, which I think may have been the intent.

Not sure if there is a reason this is done only for slurs and not for ties.

Do you think this might be tested out for general use in one of the nightlies? I've been trying to compile something myself, but I'm a complete beginner when it comes to Git and compiling/building.

I could push my branch, but you'd still still need to build it yourself, and that's actually harder than building your own. you don't actually need to understand a thing about Git in order to build the code yourself - you just need to follow the step by step instructions in the Git Workflow document. It's the compilation phase that is harder, if you are on Windows anyhow (it's a snap on Linux, not sure about Mac). But again, there is documentation - the Compilation Instructions document. Just follow them step by step.

Thanks for taking a look at this... really appreciated. As soon as I have tied up a couple of other projects, I'm going to start using Git and hopefully I can also make a few helpful contributions.

@douglas81 if you want to avoid having to build MuseScore yourself, you can simply use a nightly build available from the Download page. For each commit in the MuseScore github rep, a new build is created and offered for download.