GraphiteEditor/Graphite

Bug: Offset while using brush tool on iPad

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#3,286 opened on Oct 14, 2025

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 (11 comments) (0 reactions) (0 assignees)Rust (1,176 forks)batch import
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Description

Description

  • Large offset while using the web version on iPad.
  • Using the apple pencil to draw with the brush tool on the iPad surface, there is a large noticable offset of the ink appearing from the tip of the pencil touching the screen.
  • The brush ink also flows outside of the artboard (although I suspect this might be by desgin)

Video Demonstration

https://drive.google.com/file/d/1buYIvX035Be9K-pn0Rn7eCGvYZ4jJTX1/view?usp=sharing

Other details

  • Safari version: 26
  • iOS version: iPadOS 26.0
  • iPad model: iPad Pro 13 inch, 2024

Preliminary thoughts

Contributor guide

Research direction
Investigate the handling of touch coordinates in the brush tool to correct the offset between Apple Pencil tip and rendered ink. Specifically, check the conversion between CSS pixels and device pixels in the event handling pipeline, starting from the referenced brush tool.rs file.
Tech stack
rust
Domain
frontendbackend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
GitRust
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
75