weld FontNameBox

with custom row rendering

Change-Id: Ia909b5b9ad56b6ea4611e9ea0a1e2cb0064a8cd4
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/91841
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>

2 files changed, 307 insertions, 202 deletions

diff --git a/svtools/inc/pch/precompiled_svt.hxx b/svtools/inc/pch/precompiled_svt.hxx
index 2797de08da3a..40cfe76421db 100644
--- a/svtools/inc/pch/precompiled_svt.hxx
+++ b/svtools/inc/pch/precompiled_svt.hxx
@@ -13,7 +13,7 @@
  manual changes will be rewritten by the next run of update_pch.sh (which presumably
  also fixes all possible problems, so it's usually better to use it).
 
- Generated on 2020-02-19 12:45:36 using:
+ Generated on 2020-04-07 17:26:37 using:
  ./bin/update_pch svtools svt --cutoff=4 --exclude:system --include:module --exclude:local
 
  If after updating build fails, use the following command to locate conflicting headers:
@@ -37,6 +37,7 @@
 #include <math.h>
 #include <memory>
 #include <new>
+#include <optional>
 #include <ostream>
 #include <set>
 #include <stddef.h>
@@ -102,7 +103,6 @@
 #include <vcl/builder.hxx>
 #include <vcl/button.hxx>
 #include <vcl/checksum.hxx>
-#include <vcl/combobox.hxx>
 #include <vcl/commandevent.hxx>
 #include <vcl/ctrl.hxx>
 #include <vcl/dllapi.h>
@@ -162,6 +162,7 @@
 #include <basegfx/tuple/b2dtuple.hxx>
 #include <basegfx/tuple/b2ituple.hxx>
 #include <basegfx/tuple/b3dtuple.hxx>
+#include <basegfx/utils/common.hxx>
 #include <basegfx/vector/b2dsize.hxx>
 #include <basegfx/vector/b2dvector.hxx>
 #include <basegfx/vector/b2enums.hxx>
@@ -314,7 +315,6 @@
 #include <i18nutil/transliteration.hxx>
 #include <o3tl/cow_wrapper.hxx>
 #include <o3tl/deleter.hxx>
-#include <optional>
 #include <o3tl/safeint.hxx>
 #include <o3tl/strong_int.hxx>
 #include <o3tl/typed_flags_set.hxx>
diff --git a/svtools/source/control/ctrlbox.cxx b/svtools/source/control/ctrlbox.cxx
index 51895051551f..d1b9943dfd2c 100644
--- a/svtools/source/control/ctrlbox.cxx
+++ b/svtools/source/control/ctrlbox.cxx
@@ -61,7 +61,6 @@
 #define IMGOUTERTEXTSPACE 5
 #define EXTRAFONTSIZE 5
 #define GAPTOEXTRAPREVIEW 10
-#define MAXPREVIEWWIDTH 120
 #define MINGAPWIDTH 2
 
 #define FONTNAMEBOXMRUENTRIESFILE "/user/config/fontnameboxmruentries"
@@ -329,31 +328,43 @@ void DrawLine( OutputDevice& rDev, const basegfx::B2DPoint& rP1, const basegfx::
 
 }
 
-FontNameBox::FontNameBox( vcl::Window* pParent, WinBits nWinStyle ) :
-    ComboBox( pParent, nWinStyle )
+static Size gUserItemSz;
+static int gFontNameBoxes;
+static size_t gPreviewsPerDevice;
+static std::vector<VclPtr<VirtualDevice>> gFontPreviewVirDevs;
+static std::vector<OUString> gRenderedFontNames;
+
+FontNameBox::FontNameBox(std::unique_ptr<weld::ComboBox> p)
+    : m_xComboBox(std::move(p))
+    , mnPreviewProgress(0)
+    , mbWYSIWYG(false)
+    , maUpdateIdle("FontNameBox Preview Update")
 {
-    mbWYSIWYG = false;
+    ++gFontNameBoxes;
     InitFontMRUEntriesFile();
-}
 
-FontNameBox::~FontNameBox()
-{
-    disposeOnce();
+    maUpdateIdle.SetPriority(TaskPriority::LOWEST);
+    maUpdateIdle.SetInvokeHandler(LINK(this, FontNameBox, UpdateHdl));
 }
 
-void FontNameBox::dispose()
+FontNameBox::~FontNameBox()
 {
     if (mpFontList)
     {
         SaveMRUEntries (maFontMRUEntriesFile);
         ImplDestroyFontList();
     }
-    ComboBox::dispose();
+    --gFontNameBoxes;
+    if (!gFontNameBoxes)
+    {
+        gFontPreviewVirDevs.clear();
+        gRenderedFontNames.clear();
+    }
 }
 
-void FontNameBox::SaveMRUEntries( const OUString& aFontMRUEntriesFile ) const
+void FontNameBox::SaveMRUEntries(const OUString& aFontMRUEntriesFile) const
 {
-    OString aEntries(OUStringToOString(GetMRUEntries(),
+    OString aEntries(OUStringToOString(m_xComboBox->get_mru_entries(),
         RTL_TEXTENCODING_UTF8));
 
     if (aEntries.isEmpty() || aFontMRUEntriesFile.isEmpty())
@@ -392,7 +403,7 @@ void FontNameBox::LoadMRUEntries( const OUString& aFontMRUEntriesFile )
     aStream.ReadLine( aLine );
     OUString aEntries = OStringToOUString(aLine,
         RTL_TEXTENCODING_UTF8);
-    SetMRUEntries( aEntries );
+    m_xComboBox->set_mru_entries(aEntries);
 }
 
 void FontNameBox::InitFontMRUEntriesFile()
@@ -415,61 +426,71 @@ void FontNameBox::ImplDestroyFontList()
 void FontNameBox::Fill( const FontList* pList )
 {
     // store old text and clear box
-    OUString aOldText = GetText();
-    OUString rEntries = GetMRUEntries();
+    OUString aOldText = m_xComboBox->get_active_text();
+    OUString rEntries = m_xComboBox->get_mru_entries();
     bool bLoadFromFile = rEntries.isEmpty();
-    Clear();
+    m_xComboBox->freeze();
+    m_xComboBox->clear();
 
     ImplDestroyFontList();
     mpFontList.reset(new ImplFontList);
 
     // insert fonts
-    sal_uInt16 nFontCount = pList->GetFontNameCount();
-    for ( sal_uInt16 i = 0; i < nFontCount; i++ )
+    size_t nFontCount = pList->GetFontNameCount();
+    for (size_t i = 0; i < nFontCount; ++i)
     {
-        const FontMetric& rFontMetric = pList->GetFontName( i );
-        sal_Int32 nIndex = InsertEntry( rFontMetric.GetFamilyName() );
-        if ( nIndex < static_cast<sal_Int32>(mpFontList->size()) ) {
-            ImplFontList::iterator it = mpFontList->begin();
-            ::std::advance( it, nIndex );
-            mpFontList->insert( it, rFontMetric );
-        } else {
-            mpFontList->push_back( rFontMetric );
-        }
+        const FontMetric& rFontMetric = pList->GetFontName(i);
+        m_xComboBox->append(OUString::number(i), rFontMetric.GetFamilyName());
+        mpFontList->push_back(rFontMetric);
     }
 
-    if ( bLoadFromFile )
-        LoadMRUEntries (maFontMRUEntriesFile);
+    if (bLoadFromFile)
+        LoadMRUEntries(maFontMRUEntriesFile);
     else
-        SetMRUEntries( rEntries );
+        m_xComboBox->set_mru_entries(rEntries);
 
-    ImplCalcUserItemSize();
+    m_xComboBox->thaw();
+
+    if (mbWYSIWYG)
+    {
+        mnPreviewProgress = 0;
+        maUpdateIdle.Start();
+    }
 
     // restore text
     if (!aOldText.isEmpty())
-        SetText( aOldText );
+        set_active_or_entry_text(aOldText);
 }
 
-void FontNameBox::EnableWYSIWYG( bool bEnable )
+void FontNameBox::EnableWYSIWYG()
 {
-    if ( bEnable != mbWYSIWYG )
+    if (mbWYSIWYG)
+        return;
+    mbWYSIWYG = true;
+
+    static bool bGlobalsInited;
+    if (!bGlobalsInited)
     {
-        mbWYSIWYG = bEnable;
-        EnableUserDraw( mbWYSIWYG );
-        ImplCalcUserItemSize();
+        gUserItemSz = Size(m_xComboBox->get_approximate_digit_width() * 52, m_xComboBox->get_text_height());
+        gUserItemSz.setHeight(gUserItemSz.Height() * 16);
+        gUserItemSz.setHeight(gUserItemSz.Height() / 10);
+
+        size_t nMaxDeviceHeight = SAL_MAX_INT16 / 2; // see limitXCreatePixmap
+        gPreviewsPerDevice = nMaxDeviceHeight / gUserItemSz.Height();
+
+        bGlobalsInited = true;
     }
+
+    m_xComboBox->connect_custom_get_size(LINK(this, FontNameBox, CustomGetSizeHdl));
+    m_xComboBox->connect_custom_render(LINK(this, FontNameBox, CustomRenderHdl));
+    m_xComboBox->set_custom_renderer();
+
+    mbWYSIWYG = true;
 }
 
-void FontNameBox::ImplCalcUserItemSize()
+IMPL_STATIC_LINK_NOARG(FontNameBox, CustomGetSizeHdl, weld::ComboBox::get_size_args, Size)
 {
-    Size aUserItemSz;
-    if ( mbWYSIWYG && mpFontList )
-    {
-        aUserItemSz = Size(MAXPREVIEWWIDTH, GetTextHeight() );
-        aUserItemSz.setHeight( aUserItemSz.Height() * 16 );
-        aUserItemSz.setHeight( aUserItemSz.Height() / 10 );
-    }
-    SetUserItemSize( aUserItemSz );
+    return gUserItemSz;
 }
 
 namespace
@@ -500,192 +521,275 @@ namespace
     }
 }
 
-void FontNameBox::UserDraw( const UserDrawEvent& rUDEvt )
+IMPL_LINK_NOARG(FontNameBox, UpdateHdl, Timer*, void)
 {
-    assert( mpFontList );
+    CachePreview(mnPreviewProgress++, nullptr);
+    if (mnPreviewProgress < mpFontList->size())
+        maUpdateIdle.Start();
+}
 
-    FontMetric& rFontMetric = (*mpFontList)[ rUDEvt.GetItemId() ];
-    Point aTopLeft = rUDEvt.GetRect().TopLeft();
-    long nX = aTopLeft.X();
-    long nH = rUDEvt.GetRect().GetHeight();
+static void DrawPreview(const FontMetric& rFontMetric, const Point& rTopLeft, OutputDevice& rDevice, bool bSelected)
+{
+    rDevice.Push(PushFlags::TEXTCOLOR);
 
-    if ( mbWYSIWYG )
-    {
-        nX += IMGOUTERTEXTSPACE;
+    const StyleSettings& rStyleSettings = Application::GetSettings().GetStyleSettings();
+    if (bSelected)
+        rDevice.SetTextColor(rStyleSettings.GetHighlightTextColor());
+    else
+        rDevice.SetTextColor(rStyleSettings.GetDialogTextColor());
 
-        const bool bSymbolFont = isSymbolFont(rFontMetric);
-        vcl::RenderContext* pRenderContext = rUDEvt.GetRenderContext();
+    long nX = rTopLeft.X();
+    long nH = gUserItemSz.Height();
 
-        Color aTextColor = pRenderContext->GetTextColor();
-        vcl::Font aOldFont(pRenderContext->GetFont());
-        Size aSize( aOldFont.GetFontSize() );
-        aSize.AdjustHeight(EXTRAFONTSIZE );
-        vcl::Font aFont( rFontMetric );
-        aFont.SetFontSize( aSize );
-        pRenderContext->SetFont(aFont);
-        pRenderContext->SetTextColor(aTextColor);
+    nX += IMGOUTERTEXTSPACE;
 
-        bool bUsingCorrectFont = true;
-        tools::Rectangle aTextRect;
+    const bool bSymbolFont = isSymbolFont(rFontMetric);
 
-        // Preview the font name
-        const OUString& sFontName = rFontMetric.GetFamilyName();
+    vcl::Font aOldFont(rDevice.GetFont());
+    Size aSize( aOldFont.GetFontSize() );
+    aSize.AdjustHeight(EXTRAFONTSIZE );
+    vcl::Font aFont( rFontMetric );
+    aFont.SetFontSize( aSize );
+    rDevice.SetFont(aFont);
 
-        //If it shouldn't or can't draw its own name because it doesn't have the glyphs
-        if (!canRenderNameOfSelectedFont(*pRenderContext))
-            bUsingCorrectFont = false;
-        else
-        {
-            //Make sure it fits in the available height, shrinking the font if necessary
-            bUsingCorrectFont = shrinkFontToFit(sFontName, nH, aFont, *pRenderContext, aTextRect) != 0;
-        }
+    bool bUsingCorrectFont = true;
+    tools::Rectangle aTextRect;
 
-        if (!bUsingCorrectFont)
-        {
-            pRenderContext->SetFont(aOldFont);
-            pRenderContext->GetTextBoundRect(aTextRect, sFontName);
-        }
+    // Preview the font name
+    const OUString& sFontName = rFontMetric.GetFamilyName();
 
-        long nTextHeight = aTextRect.GetHeight();
-        long nDesiredGap = (nH-nTextHeight)/2;
-        long nVertAdjust = nDesiredGap - aTextRect.Top();
-        Point aPos( nX, aTopLeft.Y() + nVertAdjust );
-        pRenderContext->DrawText(aPos, sFontName);
-        long nTextX = aPos.X() + aTextRect.GetWidth() + GAPTOEXTRAPREVIEW;
+    //If it shouldn't or can't draw its own name because it doesn't have the glyphs
+    if (!canRenderNameOfSelectedFont(rDevice))
+        bUsingCorrectFont = false;
+    else
+    {
+        //Make sure it fits in the available height, shrinking the font if necessary
+        bUsingCorrectFont = shrinkFontToFit(sFontName, nH, aFont, rDevice, aTextRect) != 0;
+    }
 
-        if (!bUsingCorrectFont)
-            pRenderContext->SetFont(aFont);
+    if (!bUsingCorrectFont)
+    {
+        rDevice.SetFont(aOldFont);
+        rDevice.GetTextBoundRect(aTextRect, sFontName);
+    }
 
-        OUString sSampleText;
+    long nTextHeight = aTextRect.GetHeight();
+    long nDesiredGap = (nH-nTextHeight)/2;
+    long nVertAdjust = nDesiredGap - aTextRect.Top();
+    Point aPos( nX, rTopLeft.Y() + nVertAdjust );
+    rDevice.DrawText(aPos, sFontName);
+    long nTextX = aPos.X() + aTextRect.GetWidth() + GAPTOEXTRAPREVIEW;
 
-        if (!bSymbolFont)
-        {
-            const bool bNameBeginsWithLatinText = rFontMetric.GetFamilyName()[0] <= 'z';
+    if (!bUsingCorrectFont)
+        rDevice.SetFont(aFont);
 
-            if (bNameBeginsWithLatinText || !bUsingCorrectFont)
-                sSampleText = makeShortRepresentativeTextForSelectedFont(*pRenderContext);
-        }
+    OUString sSampleText;
+
+    if (!bSymbolFont)
+    {
+        const bool bNameBeginsWithLatinText = rFontMetric.GetFamilyName()[0] <= 'z';
 
-        //If we're not a symbol font, but could neither render our own name and
-        //we can't determine what script it would like to render, then try a
-        //few well known scripts
-        if (sSampleText.isEmpty() && !bUsingCorrectFont)
+        if (bNameBeginsWithLatinText || !bUsingCorrectFont)
+            sSampleText = makeShortRepresentativeTextForSelectedFont(rDevice);
+    }
+
+    //If we're not a symbol font, but could neither render our own name and
+    //we can't determine what script it would like to render, then try a
+    //few well known scripts
+    if (sSampleText.isEmpty() && !bUsingCorrectFont)
+    {
+        static const UScriptCode aScripts[] =
         {
-            static const UScriptCode aScripts[] =
-            {
-                USCRIPT_ARABIC,
-                USCRIPT_HEBREW,
-
-                USCRIPT_BENGALI,
-                USCRIPT_GURMUKHI,
-                USCRIPT_GUJARATI,
-                USCRIPT_ORIYA,
-                USCRIPT_TAMIL,
-                USCRIPT_TELUGU,
-                USCRIPT_KANNADA,
-                USCRIPT_MALAYALAM,
-                USCRIPT_SINHALA,
-                USCRIPT_DEVANAGARI,
-
-                USCRIPT_THAI,
-                USCRIPT_LAO,
-                USCRIPT_GEORGIAN,
-                USCRIPT_TIBETAN,
-                USCRIPT_SYRIAC,
-                USCRIPT_MYANMAR,
-                USCRIPT_ETHIOPIC,
-                USCRIPT_KHMER,
-                USCRIPT_MONGOLIAN,
-
-                USCRIPT_KOREAN,
-                USCRIPT_JAPANESE,
-                USCRIPT_HAN,
-                USCRIPT_SIMPLIFIED_HAN,
-                USCRIPT_TRADITIONAL_HAN,
-
-                USCRIPT_GREEK
-            };
-
-            for (const UScriptCode& rScript : aScripts)
+            USCRIPT_ARABIC,
+            USCRIPT_HEBREW,
+
+            USCRIPT_BENGALI,
+            USCRIPT_GURMUKHI,
+            USCRIPT_GUJARATI,
+            USCRIPT_ORIYA,
+            USCRIPT_TAMIL,
+            USCRIPT_TELUGU,
+            USCRIPT_KANNADA,
+            USCRIPT_MALAYALAM,
+            USCRIPT_SINHALA,
+            USCRIPT_DEVANAGARI,
+
+            USCRIPT_THAI,
+            USCRIPT_LAO,
+            USCRIPT_GEORGIAN,
+            USCRIPT_TIBETAN,
+            USCRIPT_SYRIAC,
+            USCRIPT_MYANMAR,
+            USCRIPT_ETHIOPIC,
+            USCRIPT_KHMER,
+            USCRIPT_MONGOLIAN,
+
+            USCRIPT_KOREAN,
+            USCRIPT_JAPANESE,
+            USCRIPT_HAN,
+            USCRIPT_SIMPLIFIED_HAN,
+            USCRIPT_TRADITIONAL_HAN,
+
+            USCRIPT_GREEK
+        };
+
+        for (const UScriptCode& rScript : aScripts)
+        {
+            OUString sText = makeShortRepresentativeTextForScript(rScript);
+            if (!sText.isEmpty())
             {
-                OUString sText = makeShortRepresentativeTextForScript(rScript);
-                if (!sText.isEmpty())
+                bool bHasSampleTextGlyphs = (-1 == rDevice.HasGlyphs(aFont, sText));
+                if (bHasSampleTextGlyphs)
                 {
-                    bool bHasSampleTextGlyphs = (-1 == pRenderContext->HasGlyphs(aFont, sText));
-                    if (bHasSampleTextGlyphs)
-                    {
-                        sSampleText = sText;
-                        break;
-                    }
+                    sSampleText = sText;
+                    break;
                 }
             }
+        }
 
-            static const UScriptCode aMinimalScripts[] =
-            {
-                USCRIPT_HEBREW, //e.g. biblical hebrew
-                USCRIPT_GREEK
-            };
+        static const UScriptCode aMinimalScripts[] =
+        {
+            USCRIPT_HEBREW, //e.g. biblical hebrew
+            USCRIPT_GREEK
+        };
 
-            for (const UScriptCode& rMinimalScript : aMinimalScripts)
+        for (const UScriptCode& rMinimalScript : aMinimalScripts)
+        {
+            OUString sText = makeShortMinimalTextForScript(rMinimalScript);
+            if (!sText.isEmpty())
             {
-                OUString sText = makeShortMinimalTextForScript(rMinimalScript);
-                if (!sText.isEmpty())
+                bool bHasSampleTextGlyphs = (-1 == rDevice.HasGlyphs(aFont, sText));
+                if (bHasSampleTextGlyphs)
                 {
-                    bool bHasSampleTextGlyphs = (-1 == pRenderContext->HasGlyphs(aFont, sText));
-                    if (bHasSampleTextGlyphs)
-                    {
-                        sSampleText = sText;
-                        break;
-                    }
+                    sSampleText = sText;
+                    break;
                 }
             }
         }
+    }
 
-        //If we're a symbol font, or for some reason the font still couldn't
-        //render something representative of what it would like to render then
-        //make up some semi-random text that it *can* display
-        if (bSymbolFont || (!bUsingCorrectFont && sSampleText.isEmpty()))
-            sSampleText = makeShortRepresentativeSymbolTextForSelectedFont(*pRenderContext);
+    //If we're a symbol font, or for some reason the font still couldn't
+    //render something representative of what it would like to render then
+    //make up some semi-random text that it *can* display
+    if (bSymbolFont || (!bUsingCorrectFont && sSampleText.isEmpty()))
+        sSampleText = makeShortRepresentativeSymbolTextForSelectedFont(rDevice);
 
-        if (!sSampleText.isEmpty())
-        {
-            const Size &rItemSize = rUDEvt.GetWindow()->GetOutputSize();
+    if (!sSampleText.isEmpty())
+    {
+        const Size &rItemSize = gUserItemSz;
 
-            //leave a little border at the edge
-            long nSpace = rItemSize.Width() - nTextX - IMGOUTERTEXTSPACE;
-            if (nSpace >= 0)
+        //leave a little border at the edge
+        long nSpace = rItemSize.Width() - nTextX - IMGOUTERTEXTSPACE;
+        if (nSpace >= 0)
+        {
+            //Make sure it fits in the available height, and get how wide that would be
+            long nWidth = shrinkFontToFit(sSampleText, nH, aFont, rDevice, aTextRect);
+            //Chop letters off until it fits in the available width
+            while (nWidth > nSpace || nWidth > gUserItemSz.Width())
             {
-                //Make sure it fits in the available height, and get how wide that would be
-                long nWidth = shrinkFontToFit(sSampleText, nH, aFont, *pRenderContext, aTextRect);
-                //Chop letters off until it fits in the available width
-                while (nWidth > nSpace || nWidth > MAXPREVIEWWIDTH)
-                {
-                    sSampleText = sSampleText.copy(0, sSampleText.getLength()-1);
-                    nWidth = pRenderContext->GetTextBoundRect(aTextRect, sSampleText) ?
-                             aTextRect.GetWidth() : 0;
-                }
+                sSampleText = sSampleText.copy(0, sSampleText.getLength()-1);
+                nWidth = rDevice.GetTextBoundRect(aTextRect, sSampleText) ?
+                         aTextRect.GetWidth() : 0;
+            }
 
-                //center the text on the line
-                if (!sSampleText.isEmpty() && nWidth)
-                {
-                    nTextHeight = aTextRect.GetHeight();
-                    nDesiredGap = (nH-nTextHeight)/2;
-                    nVertAdjust = nDesiredGap - aTextRect.Top();
-                    aPos = Point(nTextX + nSpace - nWidth, aTopLeft.Y() + nVertAdjust);
-                    pRenderContext->DrawText(aPos, sSampleText);
-                }
+            //center the text on the line
+            if (!sSampleText.isEmpty() && nWidth)
+            {
+                nTextHeight = aTextRect.GetHeight();
+                nDesiredGap = (nH-nTextHeight)/2;
+                nVertAdjust = nDesiredGap - aTextRect.Top();
+                aPos = Point(nTextX + nSpace - nWidth, rTopLeft.Y() + nVertAdjust);
+                rDevice.DrawText(aPos, sSampleText);
             }
         }
+    }
+
+    rDevice.SetFont(aOldFont);
+    rDevice.Pop();
+}
+
+OutputDevice& FontNameBox::CachePreview(size_t nIndex, Point* pTopLeft)
+{
+    SolarMutexGuard aGuard;
+    const FontMetric& rFontMetric = (*mpFontList)[nIndex];
+    const OUString& rFontName = rFontMetric.GetFamilyName();
+
+    size_t nPreviewIndex;
+    auto xFind = std::find(gRenderedFontNames.begin(), gRenderedFontNames.end(), rFontName);
+    bool bPreviewAvailable = xFind != gRenderedFontNames.end();
+    if (!bPreviewAvailable)
+    {
+        nPreviewIndex = gRenderedFontNames.size();
+        gRenderedFontNames.push_back(rFontName);
+    }
+    else
+        nPreviewIndex = std::distance(gRenderedFontNames.begin(), xFind);
+
+    size_t nPage = nPreviewIndex / gPreviewsPerDevice;
+    size_t nIndexInPage = nPreviewIndex - (nPage * gPreviewsPerDevice);
+
+    Point aTopLeft(0, gUserItemSz.Height() * nIndexInPage);
+
+    if (!bPreviewAvailable)
+    {
+        if (nPage >= gFontPreviewVirDevs.size())
+        {
+            gFontPreviewVirDevs.emplace_back(m_xComboBox->create_render_virtual_device());
+            VirtualDevice& rDevice = *gFontPreviewVirDevs.back();
+            rDevice.SetOutputSizePixel(Size(gUserItemSz.Width(), gUserItemSz.Height() * gPreviewsPerDevice));
+            if (vcl::Window* pDefaultDevice = dynamic_cast<vcl::Window*>(Application::GetDefaultDevice()))
+                pDefaultDevice->SetPointFont(rDevice, m_xComboBox->get_font());
+            assert(gFontPreviewVirDevs.size() == nPage + 1);
+        }
+
+        DrawPreview(rFontMetric, aTopLeft, *gFontPreviewVirDevs.back(), false);
+    }
+
+    if (pTopLeft)
+        *pTopLeft = aTopLeft;
+
+    return *gFontPreviewVirDevs[nPage];
+}
+
+IMPL_LINK(FontNameBox, CustomRenderHdl, weld::ComboBox::render_args, aPayload, void)
+{
+    vcl::RenderContext& rRenderContext = std::get<0>(aPayload);
+    const ::tools::Rectangle& rRect = std::get<1>(aPayload);
+    bool bSelected = std::get<2>(aPayload);
+    const OUString& rId = std::get<3>(aPayload);
+
+    sal_uInt32 nIndex = rId.toUInt32();
+
+    Point aDestPoint(rRect.TopLeft());
+    auto nMargin = (rRect.GetHeight() - gUserItemSz.Height()) / 2;
+    aDestPoint.AdjustY(nMargin);
 
-        pRenderContext->SetFont(aOldFont);
-        DrawEntry( rUDEvt, false, false);   // draw separator
+    if (bSelected)
+    {
+        const FontMetric& rFontMetric = (*mpFontList)[nIndex];
+        DrawPreview(rFontMetric, aDestPoint, rRenderContext, true);
     }
     else
     {
-        DrawEntry( rUDEvt, true, true );
+        // use cache of unselected entries
+        Point aTopLeft;
+        OutputDevice& rDevice = CachePreview(nIndex, &aTopLeft);
+
+        rRenderContext.DrawOutDev(aDestPoint, gUserItemSz,
+                                  aTopLeft, gUserItemSz,
+                                  rDevice);
     }
 }
 
+void FontNameBox::set_active_or_entry_text(const OUString& rText)
+{
+    const int nFound = m_xComboBox->find_text(rText);
+    if (nFound != -1)
+        m_xComboBox->set_active(nFound);
+    else
+        m_xComboBox->set_entry_text(rText);
+}
+
 FontStyleBox::FontStyleBox(std::unique_ptr<weld::ComboBox> p)
     : m_xComboBox(std::move(p))
 {
@@ -866,9 +970,13 @@ FontSizeBox::FontSizeBox(std::unique_ptr<weld::ComboBox> p)
     m_xComboBox->connect_changed(LINK(this, FontSizeBox, ModifyHdl));
 }
 
-void FontSizeBox::set_entry_text(const OUString& rText)
+void FontSizeBox::set_active_or_entry_text(const OUString& rText)
 {
-    m_xComboBox->set_entry_text(rText);
+    const int nFound = m_xComboBox->find_text(rText);
+    if (nFound != -1)
+        m_xComboBox->set_active(nFound);
+    else
+        m_xComboBox->set_entry_text(rText);
 }
 
 IMPL_LINK(FontSizeBox, ReformatHdl, weld::Widget&, rWidget, void)
@@ -1020,7 +1128,7 @@ void FontSizeBox::Fill( const FontMetric* pFontMetric, const FontList* pList )
         ++pTempAry;
     }
 
-    m_xComboBox->set_entry_text(aStr);
+    set_active_or_entry_text(aStr);
     m_xComboBox->select_entry_region(nSelectionStart, nSelectionEnd);
     m_xComboBox->thaw();
 }
@@ -1105,7 +1213,7 @@ void FontSizeBox::SetRelative( bool bNewRelative )
             Fill( &aFontMetric, pFontList );
     }
 
-    m_xComboBox->set_entry_text(aStr);
+    set_active_or_entry_text(aStr);
     m_xComboBox->select_entry_region(nSelectionStart, nSelectionEnd);
 }
 
@@ -1157,10 +1265,7 @@ void FontSizeBox::SetValue(int nNewValue, FieldUnit eInUnit)
         }
     }
     OUString aResult = format_number(nTempValue);
-    const int nFound = m_xComboBox->find_text(aResult);
-    if (nFound != -1)
-        m_xComboBox->set_active(nFound);
-    m_xComboBox->set_entry_text(aResult);
+    set_active_or_entry_text(aResult);
 }
 
 void FontSizeBox::set_value(int nNewValue)