Bullet Graph
Source: Data Visualisation Catalogue - Bullet Graph
Why This Belongs In The Compiler Gallery
Bullet graphs are compact interval charts. They use ordinary rects and marker lines, but the compiler needs to derive qualitative ranges, actual measure bars, and target markers from one raw metric row.
Data Contract
Each raw row represents one metric with ordered thresholds, an actual value, and a target.
| Field | Type | Purpose |
|---|---|---|
metric | categorical | Metric label. |
poor, satisfactory, good | quantitative | Ordered qualitative thresholds. |
actual | quantitative | Current metric value. |
target | quantitative | Target marker value. |
start, end | quantitative, derived | Range or measure bounds on the x scale. |
y, height, centerY | quantitative, derived | Bullet row geometry. |
Expected Visual
The faithful catalogue version shows background performance bands, one dark actual-value bar, and a target marker per metric. The x-axis reads the common quantitative measure.
Compiler Mapping
| Compiler part | Mapping |
|---|---|
| Data source | raw-bullets and derived bullet-ranges, bullet-measures, and bullet-targets. |
| Transform | layout with bulletRanges, bulletMeasure, and bulletTarget layout kinds. |
| Scales | Shared x: linear and ordinal range fill. |
| Guides | Generated x grid and x axis. |
| Layers | Rect qualitative bands, rect actual bars, line target markers, and text labels. |
Faithfulness Notes
The core bullet anatomy is compiler-owned. Remaining polish is label density, richer target/benchmark policies, and optional comparative small multiples.