Add a font matcher for text fonts (#2118)

novelwriter/common.py

@@ -38,7 +38,7 @@ from urllib.parse import urljoin
 from urllib.request import pathname2url
 
 from PyQt5.QtCore import QCoreApplication, QMimeData, QUrl
-from PyQt5.QtGui import QColor, QDesktopServices, QFont, QFontInfo
+from PyQt5.QtGui import QColor, QDesktopServices, QFont, QFontDatabase, QFontInfo
 
 from novelwriter.constants import nwConst, nwLabels, nwUnicode, trConst
 from novelwriter.enum import nwItemClass, nwItemLayout, nwItemType
@@ -434,6 +434,27 @@ def describeFont(font: QFont) -> str:
     return "Error"
 
 
+def fontMatcher(font: QFont) -> QFont:
+    """Make sure the font is the correct family, if possible. This
+    ensures that Qt doesn't use the GUI or document font instead.
+    """
+    info = QFontInfo(font)
+    if (famRequest := font.family()) != (famActual := info.family()):
+        logger.warning("Font mismatch: %s != %s", famRequest, famActual)
+        db = QFontDatabase()
+        if famRequest in db.families():
+            styleRequest, sizeRequest = font.styleName(), font.pointSize()
+            logger.info("Lookup: %s, %s, %d pt", famRequest, styleRequest, sizeRequest)
+            temp = db.font(famRequest, styleRequest, sizeRequest)
+            famFound, styleFound, sizeFound = temp.family(), temp.styleName(), temp.pointSize()
+            if famFound == famRequest:
+                logger.info("Found: %s, %s, %d pt", famFound, styleFound, sizeFound)
+                return temp
+        logger.warning("Could not find a font match")
+        logger.warning("You may need to restart the application")
+    return font
+
+
 def qtLambda(func: Callable, *args: Any, **kwargs: Any) -> Callable:
     """A replacement for Python lambdas that works for Qt slots."""
     def wrapper(*a_: Any) -> None:

novelwriter/formats/tokenizer.py

@@ -35,7 +35,7 @@ from PyQt5.QtCore import QLocale
 from PyQt5.QtGui import QColor, QFont
 
 from novelwriter import CONFIG
-from novelwriter.common import checkInt, numberToRoman
+from novelwriter.common import checkInt, fontMatcher, numberToRoman
 from novelwriter.constants import (
     nwHeadFmt, nwKeyWords, nwLabels, nwShortcode, nwStats, nwStyles, nwUnicode,
     trConst
@@ -304,7 +304,7 @@ class Tokenizer(ABC):
 
     def setTextFont(self, font: QFont) -> None:
         """Set the build font."""
-        self._textFont = font
+        self._textFont = fontMatcher(font)
         return
 
     def setLineHeight(self, height: float) -> None:

novelwriter/gui/doceditor.py

@@ -53,7 +53,7 @@ from PyQt5.QtWidgets import (
 )
 
 from novelwriter import CONFIG, SHARED
-from novelwriter.common import decodeMimeHandles, minmax, qtLambda, transferCase
+from novelwriter.common import decodeMimeHandles, fontMatcher, minmax, qtLambda, transferCase
 from novelwriter.constants import nwConst, nwKeyWords, nwShortcode, nwUnicode
 from novelwriter.core.document import NWDocument
 from novelwriter.enum import (
@@ -348,8 +348,9 @@ class GuiDocEditor(QPlainTextEdit):
         SHARED.updateSpellCheckLanguage()
 
         # Set the font. See issues #1862 and #1875.
-        self.setFont(CONFIG.textFont)
+        font = fontMatcher(CONFIG.textFont)
-        self._qDocument.setDefaultFont(CONFIG.textFont)
+        self.setFont(font)
+        self._qDocument.setDefaultFont(font)
         self.docHeader.updateFont()
         self.docFooter.updateFont()
         self.docSearch.updateFont()