Victory 2298 Tooltip Bug Fix

[ryansrofe]

Description

The problem occurs in voronoi-helpers.ts when calculating points for tooltips with y0 values. The issue is in the getDatasets method where the voronoi points are calculated. Currently, it calculates the voronoi point position as the midpoint between x and x0 for X coordinates, and y and y0 for Y coordinates.

// ... existing code ...
const { x, y, y0, x0 } = Helpers.getPoint(datum);
const voronoiX = (Number(x) + Number(x0)) / 2;
const voronoiY = (Number(y) + Number(y0)) / 2;
// ... existing code ...

This is problematic because for area charts using y0, the tooltip should activate based on the top line of the area (the y value), not the midpoint between y and y0. The current implementation causes tooltips to activate at points that are visually far from where users would expect them to be. This fix uses only the primary coordinates for voronoi calculations, ignoring the baseline coordinates.

// ... existing code ...
const { x, y } = Helpers.getPoint(datum);
const voronoiX = Number(x);
const voronoiY = Number(y);
// ... existing code ...

This would make the tooltips activate based on proximity to the actual data points rather than the midpoint between the top and bottom of areas, which is what users are expecting.

Fixes #2298

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• This change required a documentation update (StoryBook)

How Has This Been Tested?

I added the reporting user's code that includes the bug to Storybook and tested it in Storybook. Without this change the code produces the bug as described, with this change the bug is no longer present.

Checklist

• I have included a changeset if this change will require a version change to one of the packages.
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (Storybook)
• I have run all builds, tests, and linting and all checks pass

[changeset-bot]

🦋 Changeset detected

Latest commit: 9a50fc5

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 30 packages

Name	Type
victory-voronoi-container	Minor
victory-create-container	Minor
victory	Minor
victory-area	Minor
victory-axis	Minor
victory-bar	Minor
victory-box-plot	Minor
victory-brush-container	Minor
victory-brush-line	Minor
victory-candlestick	Minor
victory-canvas	Minor
victory-chart	Minor
victory-core	Minor
victory-cursor-container	Minor
victory-errorbar	Minor
victory-group	Minor
victory-histogram	Minor
victory-legend	Minor
victory-line	Minor
victory-native	Minor
victory-pie	Minor
victory-polar-axis	Minor
victory-scatter	Minor
victory-selection-container	Minor
victory-shared-events	Minor
victory-stack	Minor
victory-tooltip	Minor
victory-vendor	Minor
victory-voronoi	Minor
victory-zoom-container	Minor

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Name	Status	Preview	Updated (UTC)
victory	✅ Ready (Inspect)	Visit Preview	Jan 9, 2025 5:26pm

[github-actions]

Folder/File	Previous size	New size	Difference
/packages/victory/dist/victory.min.js	386.05KB	386.01KB	-0.04KB (-0.01%)
TOTAL			-0.04KB