Kdenlive UI: Advanced Editing Timeline Bar Buttons -- Odds and Ends

With the new timeline bar, Kdenlive now prominently shows its advanced timeline editing functions to make them more accessible. So what do these four (and slightly abstract) symbols do when clicked...?

Timeline Advanced Editing Functions

The advanced timeline editing functions for insert, overwrite, extract, and lift finally got their very own icons. This is important as the recently newly added timeline toolbar features the advanced editing functions now in a prominent place.

insert / overwrite / extract / lift advanced editing functions in timeline toolbar.

• insert ... a clip zone into the timeline, making room for it by shifting other clips out of the way. This is indicated by a small arrow head pointing to the right.
• overwrite ... a part of the timeline with a clip zone. Nothing moves in the timeline, you're just slapping on your clip.
• extract ... a timeline zone and close the gap by shifting all the later timeline stuff. Again, this is indicated by a small arrow head pointing to the left.
• lift ... a timeline zone so it leaves a gap in the timeline. Later timeline clips won't be shifted.

Of course, the corresponding menu items are now also using the same icons to ensure a consistent user experience.

When designing these four icons for the advanced editing functions, I started from the visual language already established and used for the editing modes normal, insert, and overwrite. Then I added established elements from the Breeze visual language: in particular, the icon blue color for insert operations, and the icon red color together with the remove/close cross shape in particular. See also Breeze Icon Design - Color of the KDE Human Interface Guidelines for more details on the Breeze style language.