tor-browser

commit 08b764a4129fa4fb78ac7fe5bbe8c1106ac872ce
parent 3e61ddfa455283191db607ebf7983dd731fd0d94
Author: Jonathan Kew <jkew@mozilla.com>
Date:   Sat, 18 Oct 2025 07:26:08 +0000

Bug 1994197 - patch 1 - Use integer nscoord values rather than gfxFloat for gfxFont::Spacing fields. r=layout-reviewers,TYLin

Differential Revision: https://phabricator.services.mozilla.com/D268559

Diffstat:
M
gfx/thebes/gfxFont.h
 | 
8
+++-----
M
layout/generic/nsTextFrame.cpp
 | 
18
+++++++++---------
M
layout/generic/nsTextFrame.h
 | 
4
++--

3 files changed, 14 insertions(+), 16 deletions(-)
diff --git a/gfx/thebes/gfxFont.h b/gfx/thebes/gfxFont.h
@@ -1652,13 +1652,11 @@ class gfxFont {
    * We let layout specify spacing on either side of any
    * character. We need to specify both before and after
    * spacing so that substring measurement can do the right things.
-   * These values are in appunits. They're always an integral number of
-   * appunits, but we specify them in floats in case very large spacing
-   * values are required.
+   * These values are in appunits.
    */
   struct Spacing {
-    gfxFloat mBefore;
-    gfxFloat mAfter;
+    nscoord mBefore;
+    nscoord mAfter;
   };
   /**
    * Metrics for a particular string
diff --git a/layout/generic/nsTextFrame.cpp b/layout/generic/nsTextFrame.cpp
@@ -3879,8 +3879,8 @@ static gfxFloat ComputeTabWidthAppUnits(const nsIFrame* aFrame) {
   RefPtr font = fm->GetThebesFontGroup()->GetFirstValidFont(' ');
   auto metrics = font->GetMetrics(vertical ? nsFontMetrics::eVertical
                                            : nsFontMetrics::eHorizontal);
-  nscoord spaceWidth = nscoord(
-      NS_round(metrics.spaceWidth * cb->PresContext()->AppUnitsPerDevPixel()));
+  nscoord spaceWidth = NSToCoordRound(metrics.spaceWidth *
+                                      cb->PresContext()->AppUnitsPerDevPixel());
   return spaces *
          (spaceWidth + styleText->mLetterSpacing.Resolve(fm->EmHeight()) +
           styleText->mWordSpacing.Resolve(spaceWidth));
@@ -4091,24 +4091,24 @@ bool nsTextFrame::PropertyProvider::GetSpacingInternal(Range aRange,
     //   0 - Gecko legacy model, spacing added to trailing side of letter
     //   1 - WebKit/Blink-compatible, spacing added to right-hand side
     //   2 - Symmetrical spacing, half added to each side
-    gfxFloat before, after;
+    nscoord before, after;
     switch (StaticPrefs::layout_css_letter_spacing_model()) {
       default:  // use Gecko legacy behavior if pref value is unknown
       case 0:
-        before = 0.0;
+        before = 0;
         after = mLetterSpacing;
         break;
       case 1:
         if (mTextRun->IsRightToLeft()) {
           before = mLetterSpacing;
-          after = 0.0;
+          after = 0;
         } else {
-          before = 0.0;
+          before = 0;
           after = mLetterSpacing;
         }
         break;
       case 2:
-        before = mLetterSpacing / 2.0;
+        before = NSToCoordRound(mLetterSpacing * 0.5);
         after = mLetterSpacing - before;
         break;
     }
@@ -4170,12 +4170,12 @@ bool nsTextFrame::PropertyProvider::GetSpacingInternal(Range aRange,
       uint32_t runOffsetInSubstring = run.GetSkippedOffset() - aRange.start;
       gfxSkipCharsIterator iter = run.GetPos();
       for (int32_t i = 0; i < run.GetRunLength(); ++i) {
-        if (!atStart && before != 0.0 &&
+        if (!atStart && before != 0 &&
             CanAddSpacingBefore(mTextRun, run.GetSkippedOffset() + i,
                                 newlineIsSignificant)) {
           aSpacing[runOffsetInSubstring + i].mBefore += before;
         }
-        if (after != 0.0 &&
+        if (after != 0 &&
             CanAddSpacingAfter(mTextRun, run.GetSkippedOffset() + i,
                                newlineIsSignificant)) {
           // End of a cluster, not in a ligature: put letter-spacing after it
diff --git a/layout/generic/nsTextFrame.h b/layout/generic/nsTextFrame.h
@@ -259,10 +259,10 @@ class nsTextFrame : public nsIFrame {
     int32_t mLength;
 
     // space for each whitespace char
-    const gfxFloat mWordSpacing;
+    const nscoord mWordSpacing;
 
     // space for each letter
-    const gfxFloat mLetterSpacing;
+    const nscoord mLetterSpacing;
 
     // If TextAutospace exists, inter-script spacing applies.
     Maybe<mozilla::TextAutospace> mTextAutospace;