PassMap renders dots when destination coordinates are missing, never invents arrows
Passes with null / missing `endX` or `endY` render as a dot at the origin, not as an omitted pass and not as an inferred trajectory. Header counts include both arrows and dots so the completion denominator stays honest.
PassMap data-integrityvisual-encodingaccessibility
Context
Providers vary in destination completeness. StatsBomb is dense, Opta F24 has gaps, and adapters that derive pass destinations from the next-event frame can leave events with only origin coordinates. Two failure modes to avoid:
- Drop the pass entirely — header counts lie; “he made 48 passes” disagrees with the rendered 41.
- Invent a destination — picks a direction and draws a fake arrow, which reads as analysis but is a hallucination.
Decision
When a pass lacks valid endX / endY, render a dot marker at the origin
and keep it in the model. All header stats (attempted, completed, completion
percentage) run over the full pass set — dots and arrows both count.
Legend gains a “unknown destination” key when any dot renders.
Consequences
- Analysts reading the chart see at a glance which passes have full trajectory data and which don’t; no hand-audit required against the raw feed.
- Static SVG export must serialise both arrow and dot glyphs for the chart to remain interpretable offline.
- Dense pass maps with high missing-endpoint rates become dot-heavy but stay readable; filtering via recipe is always available for arrow-only views.
- The dot style is configurable via
PassMapProps.dots; the fallback itself is not opt-out — invented trajectories aren’t a supported mode.