vcl: support pre-computed glyph items in OutputDevice::ImplLayout()

This allows using the SalLayoutGlyphs obtained from
GenericSalLayout::GetGlyphs() to return early in
GenericSalLayout::LayoutText().

Change-Id: If3a004f983f3578915786668bfcada00227d2eeb
Reviewed-on: https://gerrit.libreoffice.org/59169
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins

7 files changed, 22 insertions, 10 deletions

diff --git a/include/vcl/outdev.hxx b/include/vcl/outdev.hxx
index fe9af36994b8..6a91fd2527e8 100644
--- a/include/vcl/outdev.hxx
+++ b/include/vcl/outdev.hxx
@@ -150,6 +150,8 @@ namespace o3tl
 }
 
 typedef std::vector< tools::Rectangle > MetricVector;
+struct GlyphItem;
+typedef std::vector<GlyphItem> SalLayoutGlyphs;
 
 // OutputDevice-Types
 
@@ -1328,7 +1330,8 @@ public:
                                 ImplLayout( const OUString&, sal_Int32 nIndex, sal_Int32 nLen,
                                             const Point& rLogicPos = Point(0,0), long nLogicWidth=0,
                                             const long* pLogicDXArray=nullptr, SalLayoutFlags flags = SalLayoutFlags::NONE,
-                                            vcl::TextLayoutCache const* = nullptr) const;
+                                            vcl::TextLayoutCache const* = nullptr,
+                                            const SalLayoutGlyphs* pGlyphs = nullptr) const;
     SAL_DLLPRIVATE ImplLayoutArgs ImplPrepareLayoutArgs( OUString&, const sal_Int32 nIndex, const sal_Int32 nLen,
                                                          DeviceCoordinate nPixelWidth, const DeviceCoordinate* pPixelDXArray,
                                                          SalLayoutFlags flags = SalLayoutFlags::NONE,
diff --git a/include/vcl/vcllayout.hxx b/include/vcl/vcllayout.hxx
index ac61892fb415..735dc4cf748f 100644
--- a/include/vcl/vcllayout.hxx
+++ b/include/vcl/vcllayout.hxx
@@ -131,7 +131,7 @@ public:
     const Point&    DrawOffset() const                      { return maDrawOffset; }
     Point           GetDrawPosition( const Point& rRelative = Point(0,0) ) const;
 
-    virtual bool    LayoutText( ImplLayoutArgs& ) = 0;  // first step of layouting
+    virtual bool    LayoutText( ImplLayoutArgs&, const SalLayoutGlyphs* ) = 0;  // first step of layouting
     virtual void    AdjustLayout( ImplLayoutArgs& );    // adjusting after fallback etc.
     virtual void    InitFont() const {}
     virtual void    DrawText( SalGraphics& ) const = 0;
diff --git a/vcl/inc/sallayout.hxx b/vcl/inc/sallayout.hxx
index 2aa650a1c75a..a8b9e233f450 100644
--- a/vcl/inc/sallayout.hxx
+++ b/vcl/inc/sallayout.hxx
@@ -139,7 +139,7 @@ public:
     explicit        MultiSalLayout( std::unique_ptr<SalLayout> pBaseLayout );
     void            AddFallback( std::unique_ptr<SalLayout> pFallbackLayout,
                                  ImplLayoutRuns const &, const PhysicalFontFace* pFallbackFont );
-    bool            LayoutText(ImplLayoutArgs&) override;
+    bool            LayoutText(ImplLayoutArgs&, const SalLayoutGlyphs*) override;
     void            AdjustLayout(ImplLayoutArgs&) override;
     void            InitFont() const override;
 
@@ -172,7 +172,7 @@ public:
                     ~GenericSalLayout() override;
 
     void            AdjustLayout(ImplLayoutArgs&) final override;
-    bool            LayoutText(ImplLayoutArgs&) final override;
+    bool            LayoutText(ImplLayoutArgs&, const SalLayoutGlyphs*) final override;
     void            DrawText(SalGraphics&) const final override;
     std::shared_ptr<vcl::TextLayoutCache> CreateTextLayoutCache(OUString const&) const final override;
     SalLayoutGlyphs GetGlyphs() const final override;
diff --git a/vcl/source/gdi/CommonSalLayout.cxx b/vcl/source/gdi/CommonSalLayout.cxx
index 32d8e572156a..fc38b33437e1 100644
--- a/vcl/source/gdi/CommonSalLayout.cxx
+++ b/vcl/source/gdi/CommonSalLayout.cxx
@@ -263,12 +263,19 @@ bool GenericSalLayout::HasVerticalAlternate(sal_UCS4 aChar, sal_UCS4 aVariationS
     return hb_set_has(mpVertGlyphs, nGlyphIndex) != 0;
 }
 
-bool GenericSalLayout::LayoutText(ImplLayoutArgs& rArgs)
+bool GenericSalLayout::LayoutText(ImplLayoutArgs& rArgs, const SalLayoutGlyphs* pGlyphs)
 {
     // No need to touch m_GlyphItems at all for an empty string.
     if (rArgs.mnEndCharPos - rArgs.mnMinCharPos <= 0)
         return true;
 
+    if (pGlyphs)
+    {
+        // Work with pre-computed glyph items.
+        m_GlyphItems = *pGlyphs;
+        return true;
+    }
+
     hb_font_t *pHbFont = mpFont->GetHbFont();
     hb_face_t* pHbFace = hb_font_get_face(pHbFont);
 
diff --git a/vcl/source/gdi/sallayout.cxx b/vcl/source/gdi/sallayout.cxx
index 74fbd98b1c08..09cf35d8fdfe 100644
--- a/vcl/source/gdi/sallayout.cxx
+++ b/vcl/source/gdi/sallayout.cxx
@@ -1017,7 +1017,7 @@ void MultiSalLayout::AddFallback( std::unique_ptr<SalLayout> pFallback,
     ++mnLevel;
 }
 
-bool MultiSalLayout::LayoutText( ImplLayoutArgs& rArgs )
+bool MultiSalLayout::LayoutText( ImplLayoutArgs& rArgs, const SalLayoutGlyphs* )
 {
     if( mnLevel <= 1 )
         return false;
diff --git a/vcl/source/outdev/font.cxx b/vcl/source/outdev/font.cxx
index de8fae5a578d..d41ba14a0414 100644
--- a/vcl/source/outdev/font.cxx
+++ b/vcl/source/outdev/font.cxx
@@ -1334,7 +1334,7 @@ std::unique_ptr<SalLayout> OutputDevice::getFallbackFont(
     if (!pFallback)
         return nullptr;
 
-    if (!pFallback->LayoutText(rLayoutArgs))
+    if (!pFallback->LayoutText(rLayoutArgs, nullptr))
     {
         // there is no need for a font that couldn't resolve anything
         return nullptr;
@@ -1418,7 +1418,7 @@ std::unique_ptr<SalLayout> OutputDevice::ImplGlyphFallbackLayout( std::unique_pt
             break;
     }
 
-    if( pMultiSalLayout && pMultiSalLayout->LayoutText( rLayoutArgs ) )
+    if( pMultiSalLayout && pMultiSalLayout->LayoutText( rLayoutArgs, nullptr ) )
         pSalLayout = std::move(pMultiSalLayout);
 
     // restore orig font settings
diff --git a/vcl/source/outdev/text.cxx b/vcl/source/outdev/text.cxx
index 2ac6bd470451..f1747895e947 100644
--- a/vcl/source/outdev/text.cxx
+++ b/vcl/source/outdev/text.cxx
@@ -1277,7 +1277,8 @@ std::unique_ptr<SalLayout> OutputDevice::ImplLayout(const OUString& rOrigStr,
                                     sal_Int32 nMinIndex, sal_Int32 nLen,
                                     const Point& rLogicalPos, long nLogicalWidth,
                                     const long* pDXArray, SalLayoutFlags flags,
-         vcl::TextLayoutCache const* pLayoutCache) const
+         vcl::TextLayoutCache const* pLayoutCache,
+         const SalLayoutGlyphs* pGlyphs) const
 {
     // we need a graphics
     if( !mpGraphics )
@@ -1307,6 +1308,7 @@ std::unique_ptr<SalLayout> OutputDevice::ImplLayout(const OUString& rOrigStr,
     if( mpFontInstance->mpConversion ) {
         mpFontInstance->mpConversion->RecodeString( aStr, 0, aStr.getLength() );
         pLayoutCache = nullptr; // don't use cache with modified string!
+        pGlyphs = nullptr;
     }
     DeviceCoordinate nPixelWidth = static_cast<DeviceCoordinate>(nLogicalWidth);
     std::unique_ptr<DeviceCoordinate[]> xDXPixelArray;
@@ -1352,7 +1354,7 @@ std::unique_ptr<SalLayout> OutputDevice::ImplLayout(const OUString& rOrigStr,
     std::unique_ptr<SalLayout> pSalLayout = mpGraphics->GetTextLayout( aLayoutArgs, 0 );
 
     // layout text
-    if( pSalLayout && !pSalLayout->LayoutText( aLayoutArgs ) )
+    if( pSalLayout && !pSalLayout->LayoutText( aLayoutArgs, pGlyphs ) )
     {
         pSalLayout.reset();
     }