SEHI L'YI

Actually, we can provide color consistency between heatmap and bar chart by separating color to hue and saturation as mentioned in #35. However, this feature is still worth providing.

Lessen the spec level for the readability. ``` consistency: { color: { type: "shared", secondary_target: { element: "axis-label", property: "background" } } ```

THIS PART SHOULD BE MORE THOROUGHLY DETERMINED!

Ultimately, remove the data parameter!

- axis and other chart elements should be on the same level for this.

Is it possible to remove layouts and only control with consistency? - e.g., x-space and y-space consistency for superimposition

> Is it possible to remove layouts and only control with consistency? > > * e.g., x-space and y-space consistency for superimposition Added new issue for this in #53

Should add simple highlighting method for comparison targets > A possible implication of this result is that if visualization users must make unaligned bar comparisons in a stacked bar charts,...

What if I want to use multiple visual elements' distinct color like mark fill as well as mark stroke?

We need to plan whether we implement the separate explicit encoding (i.e., one of layout type), but the explicit encoding overlay is prior things to implement since it seems to...