Critical Rendering Bug in PencilKit on iPad with "More Space" Display Mode & Apple Pencil Hover Interaction

There is a significant rendering issue in PencilKit when using an iPad set to "More Space" display mode, combined with an Apple Pencil that supports hover functionality (e.g., Apple Pencil 2). This problem affects all applications that use PencilKit, including Apple's own Notes and Quick Note. The issue results in flickering black borders and subtle jittering while drawing, which is especially noticeable during tasks requiring precise handwriting, such as writing mathematical expressions. Due to the short strokes and frequent lifts and drops of the pencil, the jitter is much more pronounced, leading to visual discomfort and even dizziness after extended use.


Steps to Reproduce:

  1. Open Settings on your iPad.
  2. Navigate to Display & Brightness > Display Zoom > More Space.
  3. Switch to the More Space display mode.
  4. Open the Notes app or trigger Quick Note from any application by swiping from the bottom-right corner.
  5. Start drawing or writing using the Apple Pencil (with hover functionality) in the writing area.
  6. Observe the display anomalies as you hover and write:
    • Flickering black borders appear intermittently around the writing area.
    • The strokes show subtle jittering whenever you lift and lower the pencil. This is particularly disruptive when writing short, precise strokes, such as those in mathematical expressions, where the frequent up-and-down motion makes the jitter more apparent.

Expected Results:
Smooth and stable drawing experience with no visual artifacts or jittering during interactions with the Apple Pencil, regardless of the display zoom settings.

Actual Results:

  • Flickering black borders intermittently appear during drawing.
  • Jittering of strokes is noticeable, particularly when lifting and lowering the Apple Pencil for short strokes. This disrupts precise writing tasks, especially in cases like mathematical notation, where frequent pen lifts and short strokes make the jitter much more apparent. This can lead to discomfort (e.g., dizziness) after extended use.

System-Wide Impact:
This issue affects all apps that utilize PencilKit, including third-party apps such as Doodle Draw (link). Since PencilKit is a core framework, the rendering bug significantly degrades the user experience across multiple productivity and note-taking applications.


Similar Reports:
There are numerous discussions about this issue online, indicating that many users are experiencing the same problem.

  • Reddit Discussion: https://www.reddit.com/r/ipad/comments/1f042ol/comment/ljvilv6/
  • Apple Support Thread

Additionally, a feedback report (ID: FB15166022) related to this issue with Notes has been previously filed, but the bug remains unresolved.


This bug severely impacts the usability of PencilKit-enabled apps, especially during tasks that involve frequent, precise pencil strokes, such as writing mathematical expressions. We kindly request the development team investigate this issue promptly to ensure a smooth, stable experience with the iPad's "More Space" display mode and Apple Pencil hover interaction.

In addition to my original post, I would like to highlight that the Reddit Discussion linked above contains a short video that visually demonstrates the rendering issue with PencilKit. The video clearly shows the flickering and display problems when interacting with the Apple Pencil in "More Space" mode. This should help illustrate the issue for anyone experiencing it, as well as for the development team investigating the bug.

Here’s the link again for reference:

  • https://www.reddit.com/r/ipad/comments/1f042ol/comment/ljvilv6/
Critical Rendering Bug in PencilKit on iPad with "More Space" Display Mode & Apple Pencil Hover Interaction
 
 
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