Resolves: fdo#46923/fdo#46750 take mnSubStringMin into account

vcl/win/source/gdi/winlayout.cxx

@@ -1861,6 +1861,8 @@ int UniscribeLayout::GetNextGlyphs( int nLen, sal_GlyphId* pGlyphs, Point& rPos,
             //position so that iterating over glyph slots one at a time for
             //glyph fallback can keep context as to what characters are the
             //inputs that caused a missing glyph in a given font.
+            //
+            //See: fdo#46923/fdo#46750 for extra complexities
             {
                 int dir = 1;
                 int out = rVI.mnMinCharPos;
@@ -1871,7 +1873,7 @@ int UniscribeLayout::GetNextGlyphs( int nLen, sal_GlyphId* pGlyphs, Point& rPos,
                 }
                 for(c = rVI.mnMinCharPos; c < rVI.mnEndCharPos; ++c)
                 {
-                    int i = out;
+                    int i = out - mnSubStringMin;
                     mpGlyphs2Chars[i] = c;
                     out += dir;
                 }