Copy/Merge a selection of PatternClips into a single new pattern

[regulus79]

This PR allows the user to select a group of PatternClips on the same track, rightclick, and select the option to "Copy to New Pattern Track", which will merge the selected clips into one new clip on a new PattenTrack.

Currently, this is only implemented for MidiClips, due to the limitation of PatternClips that they cannot store more than one AutomationClip or SampleClip in a row.

[bratpeki]

So this is just a shortcut for the following:

1. Clone track
2. Clear track
3. Copy relative patterns to new track
4. Merge patterns

Am I getting it right?

[regulus79]

Afaik it is not possible to merge pattern clips which have different start offsets; this pr enables that for at least the midi clips inside patterns

[asmrtfm]

this is a total game changer for me.

great work @regulus79 !

[bratpeki]

I'm not getting it, sadly. Would a short video demonstration be alright?

[regulus79]

Basically instead of having to manually copy/split and rearrange each midi clip, you can just rightclick and select "Copy to New Pattern Track" and however the notes in the selection of PatternClips are arranged, they will be copied and merged into a new pattern.

In your original comment, you implied that this is a shortcut for cloning and clearing a pattern track, and then copying and merging the pattern clips. In a sense this is true, but the fourth step is not currently possible in lmms. Merging pattern clips is not supported due to the way pattern clips only know what pattern index they belong to, along with their start offsets. If two clips were to be merged but they had been resized and rearranged, they would have to be represented by a whole new pattern, since they are no longer a simple integer repetition of the original pattern.

To be honest I only coded this feature because someone on the discord really wanted it. I myself don't use patterns for melodies, but I guess some people do and find a tool like this useful.

2024-10-21.14-56-41.mp4