Codechange: [Win32] Pass a native GDI font description around when we…

… have one, instead of repeatedly guessing the font.

src/fontcache.cpp

@@ -737,6 +737,7 @@ class Win32FontCache : public TrueTypeFontCache {
 	virtual GlyphID MapCharToGlyph(WChar key);
 	virtual const char *GetFontName() { return WIDE_TO_MB(this->logfont.lfFaceName); }
 	virtual bool IsBuiltInFont() { return false; }
+	virtual void *GetOSHandle() { return &this->logfont; }
 };
 
 
@@ -960,13 +961,16 @@ static void LoadWin32Font(FontSize fs)
 
 	LOGFONT logfont;
 	MemSetT(&logfont, 0);
-
-	logfont.lfWeight = strcasestr(settings->font, " bold") != nullptr ? FW_BOLD : FW_NORMAL; // Poor man's way to allow selecting bold fonts.
-	logfont.lfPitchAndFamily = fs == FS_MONO ? FIXED_PITCH : VARIABLE_PITCH;
-	logfont.lfCharSet = DEFAULT_CHARSET;
-	logfont.lfOutPrecision = OUT_OUTLINE_PRECIS;
-	logfont.lfClipPrecision = CLIP_DEFAULT_PRECIS;
-	convert_to_fs(settings->font, logfont.lfFaceName, lengthof(logfont.lfFaceName), false);
+	if (settings->os_handle != nullptr) logfont = *(const LOGFONT *)settings->os_handle;
+
+	if (logfont.lfFaceName[0] == 0) {
+		logfont.lfWeight = strcasestr(settings->font, " bold") != nullptr ? FW_BOLD : FW_NORMAL; // Poor man's way to allow selecting bold fonts.
+		logfont.lfPitchAndFamily = fs == FS_MONO ? FIXED_PITCH : VARIABLE_PITCH;
+		logfont.lfCharSet = DEFAULT_CHARSET;
+		logfont.lfOutPrecision = OUT_OUTLINE_PRECIS;
+		logfont.lfClipPrecision = CLIP_DEFAULT_PRECIS;
+		convert_to_fs(settings->font, logfont.lfFaceName, lengthof(logfont.lfFaceName), false);
+	}
 
 	HFONT font = CreateFontIndirect(&logfont);
 	if (font == nullptr) {

src/fontcache.h

@@ -125,6 +125,15 @@ class FontCache {
 	 */
 	virtual const void *GetFontTable(uint32 tag, size_t &length) = 0;
 
+	/**
+	 * Get the native OS font handle, if there is one.
+	 * @return Opaque OS font handle.
+	 */
+	virtual void *GetOSHandle()
+	{
+		return nullptr;
+	}
+
 	/**
 	 * Get the name of this font.
 	 * @return The name of the font.
@@ -209,6 +218,8 @@ struct FreeTypeSubSetting {
 	char font[MAX_PATH]; ///< The name of the font, or path to the font.
 	uint size;           ///< The (requested) size of the font.
 	bool aa;             ///< Whether to do anti aliasing or not.
+
+	const void *os_handle = nullptr; ///< Optional native OS font info.
 };
 
 /** Settings for the freetype fonts. */

src/fontdetection.cpp

@@ -346,7 +346,9 @@ static int CALLBACK EnumFontCallback(const ENUMLOGFONTEX *logfont, const NEWTEXT
 	const char *english_name = font_name;
 #endif /* WITH_FREETYPE */
 
-	info->callback->SetFontNames(info->settings, font_name);
+	PLOGFONT os_data = MallocT<LOGFONT>(1);
+	*os_data = logfont->elfLogFont;
+	info->callback->SetFontNames(info->settings, font_name, os_data);
 	if (info->callback->FindMissingGlyphs(nullptr)) return 1;
 	DEBUG(freetype, 1, "Fallback font: %s (%s)", font_name, english_name);
 	return 0; // stop enumerating

src/os/windows/string_uniscribe.cpp

@@ -148,6 +148,8 @@ void UniscribeResetScriptCache(FontSize size)
 /** Load the matching native Windows font. */
 static HFONT HFontFromFont(Font *font)
 {
+	if (font->fc->GetOSHandle() != nullptr) return CreateFontIndirect((PLOGFONT)font->fc->GetOSHandle());
+
 	LOGFONT logfont;
 	ZeroMemory(&logfont, sizeof(LOGFONT));
 	logfont.lfHeight = font->fc->GetHeight();

src/strings.cpp

@@ -2068,13 +2068,18 @@ class LanguagePackGlyphSearcher : public MissingGlyphSearcher {
 		return false;
 	}
 
-	void SetFontNames(FreeTypeSettings *settings, const char *font_name) override
+	void SetFontNames(FreeTypeSettings *settings, const char *font_name, const void *os_data) override
 	{
 #if defined(WITH_FREETYPE) || defined(_WIN32)
 		strecpy(settings->small.font,  font_name, lastof(settings->small.font));
 		strecpy(settings->medium.font, font_name, lastof(settings->medium.font));
 		strecpy(settings->large.font,  font_name, lastof(settings->large.font));
-#endif /* WITH_FREETYPE */
+
+		free(settings->medium.os_handle); // Only free one, they are all the same pointer.
+		settings->small.os_handle = os_data;
+		settings->medium.os_handle = os_data;
+		settings->large.os_handle = os_data;
+#endif
 	}
 };
 
@@ -2103,8 +2108,14 @@ void CheckForMissingGlyphs(bool base_font, MissingGlyphSearcher *searcher)
 		FreeTypeSettings backup;
 		memcpy(&backup, &_freetype, sizeof(backup));
 
+		_freetype.mono.os_handle = nullptr;
+		_freetype.medium.os_handle = nullptr;
+
 		bad_font = !SetFallbackFont(&_freetype, _langpack->isocode, _langpack->winlangid, searcher);
 
+		free(_freetype.mono.os_handle);
+		free(_freetype.medium.os_handle);
+
 		memcpy(&_freetype, &backup, sizeof(backup));
 
 		if (bad_font && base_font) {

src/strings_func.h

@@ -275,8 +275,9 @@ class MissingGlyphSearcher {
 	 * Set the right font names.
 	 * @param settings  The settings to modify.
 	 * @param font_name The new font name.
+	 * @param os_data Opaque pointer to OS-specific data.
 	 */
-	virtual void SetFontNames(struct FreeTypeSettings *settings, const char *font_name) = 0;
+	virtual void SetFontNames(struct FreeTypeSettings *settings, const char *font_name, const void *os_data = nullptr) = 0;
 
 	bool FindMissingGlyphs(const char **str);
 };

src/textfile_gui.cpp

@@ -194,11 +194,13 @@ void TextfileWindow::SetupScrollbars()
 	return true;
 }
 
-/* virtual */ void TextfileWindow::SetFontNames(FreeTypeSettings *settings, const char *font_name)
+/* virtual */ void TextfileWindow::SetFontNames(FreeTypeSettings *settings, const char *font_name, const void *os_data)
 {
 #if defined(WITH_FREETYPE) || defined(_WIN32)
 	strecpy(settings->mono.font, font_name, lastof(settings->mono.font));
-#endif /* WITH_FREETYPE */
+	free(settings->mono.os_handle);
+	settings->mono.os_handle = os_data;
+#endif
 }
 
 #if defined(WITH_ZLIB)

src/textfile_gui.h

@@ -43,7 +43,7 @@ struct TextfileWindow : public Window, MissingGlyphSearcher {
 	FontSize DefaultSize() override;
 	const char *NextString() override;
 	bool Monospace() override;
-	void SetFontNames(FreeTypeSettings *settings, const char *font_name) override;
+	void SetFontNames(FreeTypeSettings *settings, const char *font_name, const void *os_data) override;
 
 	virtual void LoadTextfile(const char *textfile, Subdirectory dir);