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[BUG]: When using scattergl and zooming in significantly, the lines and dots fail to align

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#7,955 4 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
55/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
javascript
Domain
data-visualization

Research direction

Start with the provided JavaScript reproduction using Plotly.react and the scattergl trace in lines+markers mode; repeatedly zoom in to observe when the lines and dots diverge. Trace the scattergl rendering and zoom behavior until the coordinate handling is clear, then verify that the lines and markers remain aligned at extreme zoom levels.

Written by the indexing model from the issue text.

Description

bug P3 size: 1
Description

When using scattergl, I found that if I zoom in too much, the lines and dots do not align properly.

Screenshots/Video

Video

Steps to reproduce

Click the "zoom" function in the toolbox and continuously zoom in on the points until the points and lines are misaligned.

JavaScript

<html>
  <head>
    <!-- Plotly.js -->
    <meta charset="UTF-8" />
    <script
      src="https://cdn.plot.ly/plotly-3.3.0.min.js"
      charset="utf-8"
    ></script>

    <style>
      html,
      body {
        width: 100%;
        height: 100%;
        margin: 0;
        padding: 0;
        overflow: hidden;
      }

      #graphDiv {
        width: 100%;
        height: 100%;
      }
    </style>
  </head>
  <body>
    <div id="graphDiv"></div>
    <script>
      const rand = () => Math.random()
      var x = [1, 5, 10]
      var data = [
        {
          type: 'scattergl',
          mode: 'lines+markers',
          line: { color: '#b55400' },
          y: [0.000014, 0.000015, 0.000012],
          hoverinfo: 'skip',
        },
        {
          type: 'scattergl',
          mode: 'lines+markers',
        },
      ]

      var layout = {
        dragmode: 'pan',
        title: { text: '' },
        uirevision: 'true',
        xaxis: { zeroline: false, tickformat: ',d' },
        yaxis: { zeroline: false, tickformat: '.6f', automargin: true },
        responsive: true,
      }

      const graphDiv = document.getElementById('graphDiv')

      Plotly.react(graphDiv, data, layout, {
        displayModeBar: true,
        responsive: true,
      })
    </script>
  </body>
</html>
Dominant language
JavaScript
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Merged PRs (30d)
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