GUI: rethink layout and controls of PeakViewWidget
User experience suggests that many of the controls in PeakViewWidget
are unintuitive, poorly explained, and interact with other controls in unexpected ways, e.g.
- Nobody seems to understand the meaning of "preview integration regions"
- When the integration region type is changed, the units of peak end/background begin/background end change, leading to some very confusing images
- Some of the controls (e.g. peak and background colours) are poorly labelled.