Styling chart content

Chart styling controls how marks and plots appear after Swift Charts has placed their values. Color, fill, symbol, size, and stroke can encode additional data, distinguish related series, or establish emphasis without changing the scale positions that define the composition.

Some styles are derived from data through categorical or continuous style scales, while others are applied directly to resolved chart content. This difference affects generated legends, gradient alignment, and whether a visual property carries a value or only changes presentation. Patterns, symbol shapes, and stroke variations provide additional channels beyond color, allowing the chart to preserve distinctions as it adapts to accessibility settings for color differentiation, contrast, text size, and transparency.

When several related series or metrics share a chart, individual styles also need to work as a system. Related colors can preserve group structure, while variations in contrast, weight, and spacing establish hierarchy and keep dense content readable. By understanding how each treatment communicates data, grouping, or emphasis, we can style chart content without obscuring the comparison or accessible meaning it needs to preserve.