[PATCH v3 3/3] gdi32/uniscribe: Update font fallback mechanism.

[समीर सिंह Sameer Singh]

From: समीर सिंह Sameer Singh <[e-mail]>

The previous fallback only consulted the Uniscribe\Fallback registry
key and a hardcoded Windows compatible font name. If the hardcoded
font was not installed, rendering would fail entirely.

The fallback order is now:
1. Uniscribe\Fallback registry key.
2. Hardcoded Windows compatible font name, if installed.
3. Uniscribe\SystemFallback registry key.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=27641
---
 dlls/gdi32/uniscribe/usp10.c | 48 ++++++++++++++++++++++++++++++++----
 1 file changed, 43 insertions(+), 5 deletions(-)

diff --git a/dlls/gdi32/uniscribe/usp10.c b/dlls/gdi32/uniscribe/usp10.c
index 43afbaac125..c42327205fb 100644
--- a/dlls/gdi32/uniscribe/usp10.c
+++ b/dlls/gdi32/uniscribe/usp10.c
@@ -1869,7 +1869,22 @@ static BOOL requires_fallback(HDC hdc, SCRIPT_CACHE *psc, SCRIPT_ANALYSIS *psa,
     return FALSE;
 }
 
-static void find_fallback_font(enum usp10_script scriptid, WCHAR *FaceName)
+static INT CALLBACK is_font_installed_proc(const LOGFONTW *elf, const TEXTMETRICW *ntm, DWORD type, LPARAM lParam)
+{
+    return 0;
+}
+
+static BOOL is_font_installed(HDC hdc, const WCHAR *name)
+{
+    BOOL ret = FALSE;
+
+    if(!EnumFontFamiliesW(hdc, name, is_font_installed_proc, 0))
+        ret = TRUE;
+
+    return ret;
+}
+
+static void find_fallback_font(HDC hdc, enum usp10_script scriptid, WCHAR *FaceName)
 {
     HKEY hkey;
 
@@ -1880,12 +1895,35 @@ static void find_fallback_font(enum usp10_script scriptid, WCHAR *FaceName)
         DWORD type;
 
         swprintf(value, ARRAY_SIZE(value), L"%x", scriptInformation[scriptid].scriptTag);
-        if (RegQueryValueExW(hkey, value, 0, &type, (BYTE *)FaceName, &count))
-            lstrcpyW(FaceName,scriptInformation[scriptid].fallbackFont);
+        if (!RegQueryValueExW(hkey, value, 0, &type, (BYTE *)FaceName, &count))
+        {
+            RegCloseKey(hkey);
+            return;
+        }
         RegCloseKey(hkey);
     }
-    else
+
+    if (scriptInformation[scriptid].fallbackFont[0] &&
+        is_font_installed(hdc, scriptInformation[scriptid].fallbackFont))
+    {
         lstrcpyW(FaceName,scriptInformation[scriptid].fallbackFont);
+        return;
+    }
+
+    if (!RegOpenKeyA(HKEY_CURRENT_USER, "Software\\Wine\\Uniscribe\\SystemFallback", &hkey))
+    {
+        WCHAR value[10];
+        DWORD count = LF_FACESIZE * sizeof(WCHAR);
+        DWORD type;
+
+        swprintf(value, ARRAY_SIZE(value), L"%x", scriptInformation[scriptid].scriptTag);
+        if (!RegQueryValueExW(hkey, value, 0, &type, (BYTE *)FaceName, &count))
+        {
+            RegCloseKey(hkey);
+            return;
+        }
+        RegCloseKey(hkey);
+    }
 }
 
 /***********************************************************************
@@ -2025,7 +2063,7 @@ HRESULT WINAPI ScriptStringAnalyse(HDC hdc, const void *pString, int cString,
                 GetObjectW(GetCurrentObject(hdc, OBJ_FONT), sizeof(lf), & lf);
                 lf.lfCharSet = scriptInformation[analysis->pItem[i].a.eScript].props.bCharSet;
                 lf.lfFaceName[0] = 0;
-                find_fallback_font(analysis->pItem[i].a.eScript, lf.lfFaceName);
+                find_fallback_font(hdc, analysis->pItem[i].a.eScript, lf.lfFaceName);
                 if (lf.lfFaceName[0])
                 {
                     analysis->glyphs[i].fallbackFont = CreateFontIndirectW(&lf);
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/10672