6562639: Wrong pixel bounds from TextLayout with white font

[gredler]

One of the possible code paths for TextLayout.getPixelBounds(...) actually draws the text on a Graphics2D and checks the image pixels afterwards. The text is drawn over a white background, so if the user sets the font's foreground color to white then the text pixels cannot be detected (white on white).

This PR fixes the issue by removing the code that sets the background to white, leaving the background as the default ARGB color (0 = transparent black). This does not cause a new problem for users who might set their font foreground color to transparent black, because transparent font foreground colors always return an empty bounds anyway (by virtue of being transparent).

The updated code should also be slightly faster since it's doing less work, though I haven't run any performance tests.

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-6562639: Wrong pixel bounds from TextLayout with white font (Bug - P4)

Reviewers

• Phil Race (@prrace - Reviewer) Review applies to ad0ff83a
• Sergey Bylokhov (@mrserb - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/28809/head:pull/28809
$ git checkout pull/28809

Update a local copy of the PR:
$ git checkout pull/28809
$ git pull https://git.openjdk.org/jdk.git pull/28809/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 28809

View PR using the GUI difftool:
$ git pr show -t 28809

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/28809.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back dgredler! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@gredler This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

6562639: Wrong pixel bounds from TextLayout with white font

Reviewed-by: serb, prr

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 175 new commits pushed to the master branch:

• efb79dc: 8374444: Fix simple -Wzero-as-null-pointer-constant warnings
• 05d2f7f: 8373847: Test javax/swing/JMenuItem/MenuItemTest/bug6197830.java failed because The test case automatically fails when clicking any items in the “Nothing” menu in all four windows (Left-to-right)-Menu Item Test and (Right-to-left)-Menu Item Test
• 2ea3c00: 4337898: Serializing DefaultTableCellRenderer changes colors
• ... and 172 more: https://git.openjdk.org/jdk/compare/d854a04231a437a6af36ae65780961f40f336343...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[openjdk]

@gredler The following label will be automatically applied to this pull request:

• client

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing list. If you would like to change these labels, use the /label pull request command.

[mlbridge]

Webrevs

• 01: Full - Incremental (dbac4944)
• 00: Full (ad0ff83a)

[prrace]

all our existing normal tests passed, as well as the new one.

[gredler]

Does anyone have time to provide a second review on this PR before the end of the year? Phil has already verified that all tests pass. Thanks!

[mrserb]

Seems the year in the header should be bumped =(

[gredler]

/integrate

[openjdk]

Going to push as commit 62181b6.
Since your change was applied there have been 201 commits pushed to the master branch:

• 3f65215: 8374340: FontRenderContext instance variables should be final
• 136ac0d: 8374433: java/util/Locale/PreserveTagCase.java does not run any tests
• c611da2: 8374483: Eliminate :serviceability_ttf_virtual group and mark svc non-virtual tests with requires
• ... and 198 more: https://git.openjdk.org/jdk/compare/d854a04231a437a6af36ae65780961f40f336343...master

Your commit was automatically rebased without conflicts.

[openjdk]

@gredler Pushed as commit 62181b6.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.