FFT-DataViz-Designer - Chart Form & Encoding
Overview
Section titled “Overview”FFT-DataViz-Designer is the presentation leaf of FlowForge’s Data & Analytics crew — the dashboard
specialist that decides which chart tells which truth. It maps indicator kind to chart form
against the perception canon, composes what belongs on one screen, and emits a chart spec in
data→mark→encoding terms that fft-web-designer or fft-tui-designer styles and fft-frontend
or fft-tui builds. It decides form and encoding, never styling, never the metric itself, and
never the rendering code.
Capabilities
Section titled “Capabilities”- Indicator-to-form mapping: the chart form each indicator earns, per the Cleveland–McGill ranking of perceptual tasks — position before length, length before area, area before colour
- Dashboard composition: Few’s one-screen discipline — what earns a tile, what earns a sparkline, what belongs in a table, and what does not belong at all
- Encoding specs: grammar-of-graphics terms — what maps to position, length, colour, shape — so the spec is implementable without guesswork
- Data-ink discipline: Tufte’s data-ink ratio and Wilke’s proportional-ink rule, including when a truncated axis misleads and when it clarifies
- Accessibility floor: Okabe–Ito / Wong CVD-safe palettes, colour never the sole channel, and unknown rendered as unknown rather than as zero
- Reference vocabulary: the FT Visual Vocabulary as the shared naming of forms, so a spec and its build mean the same chart
When to Use
Section titled “When to Use”- Routing rule: presentation questions — which chart, which encoding, what fits one screen →
fft-dataviz-designer; it hands the chart spec to the design org’s leaf for visual craft - Designing a dashboard or a report’s visual structure from a set of indicators
- Auditing a chart that is technically correct but reads wrong, or that leans on colour alone
- Turning a measurement brief’s indicators into an implementable chart spec
Do NOT dispatch to define a metric (fft-analytics-architect) or to compute one (fft-data-analyst). Do NOT dispatch for brand palette, spacing or typography — that is fft-design-architect’s leaves — nor for the rendering code, which is fft-frontend or fft-tui.
Example Prompts
Section titled “Example Prompts”"Here are the eight indicators the measurement brief defines. Decide the chart form each one earns, what belongs on one screen, and emit the chart spec — including the CVD-safe encoding and how unknown renders.""This throughput chart is correct but everyone misreads it. Audit the form and encoding against the perception canon and specify the replacement."