ADDITIONAL SYSTEM INFORMATION :
Not reproducible on MS Windows. Reproduced on:
- zulu17.48.15-ca-jdk17.0.0-macosx_aarch64 with `-Dsun.java2d.metal=true`
- temurin17.0.13+11 aarch64 (aka OpenJDK17U-jdk_aarch64_mac_hotspot_17.0.13_11) `with -Dsun.java2d.metal=true`
- zulu19.0.45-ea-jdk19.0.0-ea.18-macosx_aarch64 and zulu21.38.21-ca-jdk21.0.5-macosx_aarch64 without additional system properties

A DESCRIPTION OF THE PROBLEM :
Some TrueType fonts are rendered by method `java.awt.Graphics2D#drawString` incorrectly in VolatileImage in the Metal rendering pipeline on macOS. The resulting image has diagonal artifacts.

The root cause was found to be JDK-8284378 by bisecting on JDK versions, which landed me on zulu19.0.43-ea-jdk19.0.0-ea.17-macosx_aarch64 as the last good version and zulu19.0.45-ea-jdk19.0.0-ea.18-macosx_aarch64 as the first bad version. Then I looked at this range of versions in the JDK 19 updates repository:

  $ git log jdk-19+17..jdk-19+18 --oneline -- '*macosx*'
  f4edb59a6e4 8284567: Collapse identical catch branches in java.base
  3a0ddeba52b 8284378: Make Metal the default Java 2D rendering pipeline for macOS
  192886546bf 8284166: [macos] Replace deprecated alternateSelectedControlColor with selectedContentBackgroundColor

Workaround
Disable the Metal rendering pipeline by passing a system property -Dsun.java2d.metal=false or -Dsun.java2d.opengl=true to the JVM.

REGRESSION : Last worked in version 18

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Prerequisites
Requirements for the bug reproduction:
1) macOS aarch64
2) Metal rendering pipeline is used. See JDK-8284378 "Make Metal the default Java 2D rendering pipeline for macOS" for details.
3) VolatileImage is used
4) Default desktop rendering hints (from "awt.font.desktophints") are added
5) A TrueType font is used. In this reproducer, the file OpenSans-Regular.ttf downloaded from Google Fonts is used.
6) Font size is less than 51.

Steps to reproduce
1) Launch class swing.MetalFontRenderingBug (attached), with swing/OpenSans-Regular.ttf in resources
2) Observe the text in the demo's window

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The text in the window ("Font: Open Sans Regular, size: 50") is readable.
ACTUAL -
The text in the window is unreadable with some kind of diagonal artifacts.