LibWeb/CSS: Implement the font-kerning property

This sets whether the kerning information stored on the current font is used.
Author: https://github.com/tcl3 Commit: 9b6da84fff Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/5168 Reviewed-by: https://github.com/AtkinsSJ ✅
2025-07-28 19:59:17 +00:00 · 2025-06-22 18:59:42 +01:00 · 2025-06-22 18:59:42 +01:00 · 9b6da84fff · 2025-06-23 12:28:02 +00:00
commit 9b6da84fff
parent 80ea865b19
17 changed files with 108 additions and 20 deletions
--- a/Libraries/LibWeb/Layout/InlineLevelIterator.cpp
+++ b/Libraries/LibWeb/Layout/InlineLevelIterator.cpp
@ -417,6 +417,20 @@ HashMap<StringView, u8> InlineLevelIterator::shape_features_map() const
        }
    }

+    // FIXME: vkrn should be enabled for vertical text.
+    switch (computed_values.font_kerning()) {
+    case CSS::FontKerning::Auto:
+        // FIXME: Use a heuristic to determine whether to enable kerning.
+    case CSS::FontKerning::Normal:
+        features.set("kern"sv, 1);
+        break;
+    case CSS::FontKerning::None:
+        features.set("kern"sv, 0);
+        break;
+    default:
+        break;
+    }
+
    return features;
 }