The reason for this is that while we keep a list of selected keyframes to move and paint on the timeline, a keyframe also has its own "isSelected" state. This state is backed up through undo/redo operations while the layer::getSelectedFrames is not.
We use the isSelected state to ignore selected frames in the TimeLineCells::paintFrames while we use Layer::getSelectedFrames() to paint the selected frames.
This means that we can get into a situation where the frame is neither painted as selected nor non selected because of the two different sources of truth.
The solution is to remove one of the sources. As such, I went ahead and removed isSelected from Keyframe, so there's only one truth. By doing so, said frames can no longer be put in a selected state through undo/redo operations, which I personally think is good. I've inspected a few other applications which does also not keep selections as undo/redo'able state.
To that end my conclusion is that we shouldn't have to do that either.
The reason for this is that while we keep a list of selected keyframes to move and paint on the timeline, a keyframe also has its own "isSelected" state. This state is backed up through undo/redo operations while the layer::getSelectedFrames is not. We use the isSelected state to ignore selected frames in the TimeLineCells::paintFrames while we use Layer::getSelectedFrames() to paint the selected frames.
This means that we can get into a situation where the frame is neither painted as selected nor non selected because of the two different sources of truth.
The solution is to remove one of the sources. As such, I went ahead and removed isSelected from Keyframe, so there's only one truth. By doing so, said frames can no longer be put in a selected state through undo/redo operations, which I personally think is good. I've inspected a few other applications which does also not keep selections as undo/redo'able state.
To that end my conclusion is that we shouldn't have to do that either.
fixes #1873