Fix: Calculate em unit based on font size rather than line height#242
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Fix: Calculate em unit based on font size rather than line height#242chenjt2001 wants to merge 1 commit into
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Pull request overview
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Updates how GetEmHeight() computes the “em” height for layout calculations in the CSS box model.
Changes:
- Changed
GetEmHeight()from usingActualFont.Heightto aSize * 96/72conversion formula.
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| return ActualFont.Size * 96d / 72d; | ||
| } |
Comment on lines
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| return ActualFont.Size * 96d / 72d; | ||
| } |
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Description
This PR fixes an issue where the
emunit was incorrectly calculated using the font's line height (ActualFont.Height) instead of the font size.Motivation
I discovered this bug when applying
text-indent: 2em;to a<p>tag. The resulting indentation was noticeably larger than the expected width of two full-width characters.The root cause was in
CssBoxProperties.GetEmHeight(), which returned the line height. By updating the calculation toActualFont.Size * 96d / 72d(converting points to pixels), theemunit now matches the actual font size.Before Fix:
After Fix:
