[FreeType] Some character sequences with a variation selector are not rendered
https://bugs.webkit.org/show_bug.cgi?id=197838

Reviewed by Michael Catanzaro.

We get the invalid glyph instead. See http://mts.io/2015/04/21/unicode-symbol-render-text-emoji/. In the table at
the end the Emoji and Text columns are not correctly rendered. It happens also when copying an emoji from
GtkEmojiChooser and pasting in WebKit text field, because GTK appends U+FE0F to all emojis to force the emoji
style. We need to take into account the variation selector when checking if a font can render a combining
sequence, using FT_Face_GetCharVariantIndex to get the right glyph in case of variation character present.

* platform/graphics/Font.cpp:
(WebCore::Font::platformSupportsCodePoint const): Add optional variation parameter.
(WebCore::Font::canRenderCombiningCharacterSequence const): Take into account variation selector characters
* platform/graphics/Font.h:
* platform/graphics/cairo/FontCairoHarfbuzzNG.cpp:
(WebCore::FontCascade::fontForCombiningCharacterSequence const): Check variation selectors 0xFE0E and 0xFE0F to
decide whether to use the emoji or text style.
* platform/graphics/cocoa/FontCocoa.mm:
(WebCore::Font::platformSupportsCodePoint const): Return false when a variation character is passed so that
characters are checked individually.
* platform/graphics/freetype/SimpleFontDataFreeType.cpp:
(WebCore::Font::platformSupportsCodePoint const): Use FT_Face_GetCharVariantIndex when a variation character is
passed.
* platform/graphics/harfbuzz/ComplexTextControllerHarfBuzz.cpp:
(WebCore::harfBuzzFontFunctions): Do not return true when FT_Face_GetCharVariantIndex returns 0.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@245393 268f45cc-cd09-0410-ab3c-d52691b4dbfc
7 files changed
tree: 1d517178cf7922723de5ea9470ad1b3eee8c8cbb
  1. Examples/
  2. JSTests/
  3. LayoutTests/
  4. ManualTests/
  5. PerformanceTests/
  6. Source/
  7. Tools/
  8. WebDriverTests/
  9. WebKit.xcworkspace/
  10. WebKitLibraries/
  11. WebPlatformTests/
  12. Websites/
  13. .clang-format
  14. .dir-locals.el
  15. .gitattributes
  16. .gitignore
  17. ChangeLog
  18. ChangeLog-2012-05-22
  19. ChangeLog-2018-01-01
  20. CMakeLists.txt
  21. Makefile
  22. Makefile.shared
  23. ReadMe.md
ReadMe.md

WebKit

WebKit is a cross-platform web browser engine. On iOS and macOS, it powers Safari, Mail, iBooks, and many other applications.

Feature Status

Visit WebKit Feature Status page to see which Web API has been implemented, in development, or under consideration.

Trying the Latest

On macOS, download Safari Technology Preview to test the latest version of WebKit. On Linux, download Epiphany Technology Preview. On Windows, you'll have to build it yourself.

Reporting Bugs

  1. Search WebKit Bugzilla to see if there is an existing report for the bug you've encountered.
  2. Create a Bugzilla account to to report bugs (and to comment on them) if you haven't done so already.
  3. File a bug in accordance with our guidelines.

Once your bug is filed, you will receive email when it is updated at each stage in the bug life cycle. After the bug is considered fixed, you may be asked to download the latest nightly and confirm that the fix works for you.

Getting the Code

On Windows, follow the instructions on our website.

Cloning the Git SVN Repository

Run the following command to clone WebKit's Git SVN repository:

git clone git://git.webkit.org/WebKit.git WebKit

or

git clone https://git.webkit.org/git/WebKit.git WebKit

If you want to be able to commit changes to the repository, or just want to check out branches that aren’t contained in WebKit.git, you will need track WebKit's Subversion repository. You can run the following command to configure this and other options of the new Git clone for WebKit development.

Tools/Scripts/webkit-patch setup-git-clone

For information about this, and other aspects of using Git with WebKit, read the wiki page.

Checking out the Subversion Repository

If you don‘t want to use Git, run the following command to check out WebKit’s Subversion repository:

svn checkout https://svn.webkit.org/repository/webkit/trunk WebKit

Building WebKit

Building macOS Port

Install Xcode and its command line tools if you haven't done so already:

  1. Install Xcode Get Xcode from https://developer.apple.com/downloads. To build WebKit for OS X, Xcode 5.1.1 or later is required. To build WebKit for iOS Simulator, Xcode 7 or later is required.
  2. Install the Xcode Command Line Tools In Terminal, run the command: xcode-select --install

Run the following command to build a debug build with debugging symbols and assertions:

Tools/Scripts/build-webkit --debug

For performance testing, and other purposes, use --release instead.

Using Xcode

You can open WebKit.xcworkspace to build and debug WebKit within Xcode.

If you don't use a custom build location in Xcode preferences, you have to update the workspace settings to use WebKitBuild directory. In menu bar, choose File > Workspace Settings, then click the Advanced button, select “Custom”, “Relative to Workspace”, and enter WebKitBuild for both Products and Intermediates.

Building iOS Port

The first time after you install a new Xcode, you will need to run the following command to enable Xcode to build command line tools for iOS Simulator:

sudo Tools/Scripts/configure-xcode-for-ios-development

Without this step, you will see the error message: “target specifies product type ‘com.apple.product-type.tool’, but there’s no such product type for the ‘iphonesimulator’ platform.” when building target JSCLLIntOffsetsExtractor of project JavaScriptCore.

Run the following command to build a debug build with debugging symbols and assertions for iOS:

Tools/Scripts/build-webkit --debug --ios-simulator

Building the GTK+ Port

For production builds:

cmake -DPORT=GTK -DCMAKE_BUILD_TYPE=RelWithDebInfo -GNinja
ninja
sudo ninja install

For development builds:

Tools/gtk/install-dependencies
Tools/Scripts/update-webkitgtk-libs
Tools/Scripts/build-webkit --gtk --debug

For more information on building WebKitGTK+, see the wiki page.

Building the WPE Port

For production builds:

cmake -DPORT=WPE -DCMAKE_BUILD_TYPE=RelWithDebInfo -GNinja
ninja
sudo ninja install

For development builds:

Tools/wpe/install-dependencies
Tools/Scripts/update-webkitwpe-libs
Tools/Scripts/build-webkit --wpe --debug

Building Windows Port

For building WebKit on Windows, see the wiki page.

Running WebKit

With Safari and Other macOS Applications

Run the following command to launch Safari with your local build of WebKit:

Tools/Scripts/run-safari --debug

The run-safari script sets the DYLD_FRAMEWORK_PATH environment variable to point to your build products, and then launches /Applications/Safari.app. DYLD_FRAMEWORK_PATH tells the system loader to prefer your build products over the frameworks installed in /System/Library/Frameworks.

To run other applications with your local build of WebKit, run the following command:

Tools/Scripts/run-webkit-app <application-path>

iOS Simulator

Run the following command to launch iOS simulator with your local build of WebKit:

run-safari --debug --ios-simulator

In both cases, if you have built release builds instead, use --release instead of --debug.

Linux Ports

If you have a development build, you can use the run-minibrowser script, e.g.:

run-minibrowser --debug --wpe

Pass one of --gtk, --jsc-only, or --wpe to indicate the port to use.

Contribute

Congratulations! You’re up and running. Now you can begin coding in WebKit and contribute your fixes and new features to the project. For details on submitting your code to the project, read Contributing Code.