Display individual spectra in multi-spectral SPE files #19
Description
speview supports reading of multi-spectral SPE files (e.g. images or time-series), however, it displays all lines in the same color on top of each other. If there are 256 spectra in the file, you just cannot distinguish between them!
Proposal
We modify and extend class DataItem. New functionality: if a multi-spectral file is opened, we display it as a set of individual lines with the same color, but one of them is opaque, and other are semi-transparent. The transparency depends on the distance to the so-called "active line". The active line is selected by rotating the mouse wheel. This allows us to easily visualize a particular data line from the multi-spectral SPE file. In the legend we display the number of an active line. The active line remains selected until we exit the application, even if we go to another file.