Cairo: Update font after restore

Update font after restore (Q operator) if font has changed.
This is important when entering text into forms if there
are characters shown by default font after characters
which needed new font.

New method getRef() where added to CairoFont class to
be able to easily compare fonts.

3 files changed, 11 insertions, 1 deletions

diff --git a/poppler/CairoFontEngine.h b/poppler/CairoFontEngine.h
index 56cc8825..c97e0ea4 100644
--- a/poppler/CairoFontEngine.h
+++ b/poppler/CairoFontEngine.h
@@ -22,6 +22,7 @@
 // Copyright (C) 2013 Thomas Freitag <Thomas.Freitag@alfa.de>
 // Copyright (C) 2018 Adam Reichold <adam.reichold@t-online.de>
 // Copyright (C) 2022 Oliver Sander <oliver.sander@tu-dresden.de>
+// Copyright (C) 2022 Marek Kasik <mkasik@redhat.com>
 //
 // To see a description of the changes please see the Changelog file that
 // came with your tarball or type make ChangeLog if you are building from git
@@ -59,6 +60,8 @@ public:
 
     bool isSubstitute() { return substitute; }
 
+    Ref getRef() { return ref; }
+
 protected:
     Ref ref;
     cairo_font_face_t *cairo_font_face;
diff --git a/poppler/CairoOutputDev.cc b/poppler/CairoOutputDev.cc
index b402cc8b..a72c218a 100644
--- a/poppler/CairoOutputDev.cc
+++ b/poppler/CairoOutputDev.cc
@@ -31,7 +31,7 @@
 // Copyright (C) 2015 Suzuki Toshiya <mpsuzuki@hiroshima-u.ac.jp>
 // Copyright (C) 2018 Klarälvdalens Datakonsult AB, a KDAB Group company, <info@kdab.com>. Work sponsored by the LiMux project of the city of Munich
 // Copyright (C) 2018, 2020 Adam Reichold <adam.reichold@t-online.de>
-// Copyright (C) 2019, 2020 Marek Kasik <mkasik@redhat.com>
+// Copyright (C) 2019, 2020, 2022 Marek Kasik <mkasik@redhat.com>
 // Copyright (C) 2020 Michal <sudolskym@gmail.com>
 // Copyright (C) 2020, 2022 Oliver Sander <oliver.sander@tu-dresden.de>
 // Copyright (C) 2021 Uli Schlachter <psychon@znc.in>
@@ -357,6 +357,7 @@ void CairoOutputDev::saveState(GfxState *state)
     elem.stroke_opacity = stroke_opacity;
     elem.mask = mask ? cairo_pattern_reference(mask) : nullptr;
     elem.mask_matrix = mask_matrix;
+    elem.fontRef = currentFont ? currentFont->getRef() : Ref::INVALID();
     saveStateStack.push_back(elem);
 
     if (strokePathClip) {
@@ -384,6 +385,10 @@ void CairoOutputDev::restoreState(GfxState *state)
     stroke_color = {};
     stroke_opacity = saveStateStack.back().stroke_opacity;
 
+    if (saveStateStack.back().fontRef != (currentFont ? currentFont->getRef() : Ref::INVALID())) {
+        needFontUpdate = true;
+    }
+
     /* This isn't restored by cairo_restore() since we keep it in the
      * output device. */
     updateBlendMode(state);
diff --git a/poppler/CairoOutputDev.h b/poppler/CairoOutputDev.h
index c287bf5c..5ce877d2 100644
--- a/poppler/CairoOutputDev.h
+++ b/poppler/CairoOutputDev.h
@@ -27,6 +27,7 @@
 // Copyright (C) 2018 Klarälvdalens Datakonsult AB, a KDAB Group company, <info@kdab.com>. Work sponsored by the LiMux project of the city of Munich
 // Copyright (C) 2020 Michal <sudolskym@gmail.com>
 // Copyright (C) 2021 Christian Persch <chpe@src.gnome.org>
+// Copyright (C) 2022 Marek Kasik <mkasik@redhat.com>
 //
 // To see a description of the changes please see the Changelog file that
 // came with your tarball or type make ChangeLog if you are building from git
@@ -381,6 +382,7 @@ protected:
         double stroke_opacity;
         cairo_pattern_t *mask; // can be null
         cairo_matrix_t mask_matrix;
+        Ref fontRef;
     };
     std::vector<SaveStateElement> saveStateStack;
 };