Reframe tissue curves on hover, enriching expression comparison

[eweitz]

This helps compare gene expression in the focused tissue to that in other tissues, via an animated change in perspective.

Reframe_gene-tissue_expression_distirbution_curves_on_hover__Ideogram_2024-01-14.mov

Previously (#365) a given gene's expression in almost all top-expressed tissues often couldn't be usefully compared. That's because, in many cases, one of the ten tissues has a maximum expression drastically higher than all the others. The most expressed tissue would cause the distribution curves for all other tissues to be quite small and narrow. The distribution in other tissues was often indiscernible, beyond looking "very low".

Now, expression in those non-dominant tissues -- which is often biologically relevant -- can be compared in detail.

The focused tissue becomes the new coordinate reference for all tissues. The reference tissue gets scaled and translated to occupy the full width available to mini-curves. Other mini-curves get transformed to be viewed from the perspective of the focused tissue. To clarify what's happening, the coordinate reframing is animated. The expression distribution curves change form in a brief, smooth transition rather than a discontinuous snap from start to end state. This makes the novel scientific visualization technique more engaging and intuitive.

Other aspects of distribution curves, and protein feature colors, were also refined.