[jdk25u] Integrated: 8361381: GlyphLayout behavior differs on JDK 11+ compared to JDK 8

[Vishal Chand]

On Thu, 13 Nov 2025 23:10:47 GMT, Vishal Chand <duke at openjdk.org> wrote:

> Backporting:
> 
> 8361381: GlyphLayout behavior differs on JDK 11+ compared to JDK 8
> 
> Summary of the change:
> * Fixes a regression in HarfBuzz-based text layout in JDK 9+ where GlyphLayout incorrectly clustered characters in complex scripts (e.g., Khmer) due to faulty “each glyph maps to one character” assumptions.
> * Adjusts the clustering algorithm in `ExtendedTextSourceLabel::createCharinfo()` by removing the needless `clusterExtraGlyphs` logic so line-breaking and wrapping behave consistently with JDK 8.
> 
> Testing:
> * tests in `test/jdk/java/awt/font/` are passing locally on Amazon Linux 2.
> 
> Applies cleanly, low risk.

This pull request has now been integrated.

Changeset: 2ed77bee
Author:    Vishal Chand <vishalvc at amazon.com>
Committer: Volker Simonis <simonis at openjdk.org>
URL:       https://git.openjdk.org/jdk25u/commit/2ed77bee88c4f17f58e01d80237472dd14613494
Stats:     141 lines in 3 files changed: 133 ins; 5 del; 3 mod

8361381: GlyphLayout behavior differs on JDK 11+ compared to JDK 8

Reviewed-by: simonis
Backport-of: bcff857ba09028cc43e856726b5c839cc6b1b0d9

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PR: https://git.openjdk.org/jdk25u/pull/379