Designing Visualizations
The Visual tab controls how the data is drawn. A visualization is made of one or more units — each unit is a single chart with a mark type and a set of visual encodings.
Mark
Each unit draws the data with one mark type: point, line, bar, or area. For the stocks example, the default is line; switching it to point turns the multi-series line chart into a scatterplot of the same encodings.
Encodings
A unit's encodings list which fields map to which visual properties. Umwelt supports:
| Property | Meaning |
|---|---|
x, y | Position |
color | Hue (typically for categories) |
shape | Point shape |
size | Mark size |
opacity | Mark opacity |
order | Drawing order |
facet | Split into small multiples by category |
Encodings are usually assigned from the Fields tab, but each encoding also appears here with its own controls: change which field it uses, remove it, or override the field's transforms for this encoding only. The transform dropdowns offer Inherit (use whatever the field definition says), None (explicitly no transform, even if the field has one), or a specific value.
Multiple units and composition
Press Add visual unit to create additional charts. With more than one unit, each gets a name (which you can edit — names are how encodings refer to units) and a Composition control appears:
- layer — draw the units on top of each other in one view.
- concat — place the units side by side as separate views.
A common pattern is concatenating two units that show different fields of the same data — the shared key keeps selections coordinated across them.
Next
- Designing Sonifications — the audio counterpart to this tab.
- Exploring the Viewer — how the rendered chart interacts with the other views.