vcl: less text layout calls in Menu

Number of GenericSalLayout::LayoutText() calls for each & every menu
item till a Writer document is opened: 3 (before) -> 1 (after).

Change-Id: I08a3d174bf15bafbcbce612712f2ab773cd5e085
Reviewed-on: https://gerrit.libreoffice.org/60045
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins

1 files changed, 23 insertions, 0 deletions

diff --git a/vcl/source/window/menuitemlist.cxx b/vcl/source/window/menuitemlist.cxx
index 1d63118af096..7be1f22f917e 100644
--- a/vcl/source/window/menuitemlist.cxx
+++ b/vcl/source/window/menuitemlist.cxx
@@ -38,6 +38,29 @@ MenuItemData::~MenuItemData()
     pSubMenu.disposeAndClear();
 }
 
+SalLayoutGlyphs* MenuItemData::GetTextGlyphs(OutputDevice* pOutputDevice)
+{
+    if (!aTextGlyphs.empty())
+        // Use pre-calculated result.
+        return &aTextGlyphs;
+
+    OUString aNonMnemonicString = OutputDevice::GetNonMnemonicString(aText);
+    std::unique_ptr<SalLayout> pLayout
+        = pOutputDevice->ImplLayout(aNonMnemonicString, 0, aNonMnemonicString.getLength(),
+                                    Point(0, 0), 0, nullptr, SalLayoutFlags::GlyphItemsOnly);
+    if (!pLayout)
+        return nullptr;
+
+    const SalLayoutGlyphs* pGlyphs = pLayout->GetGlyphs();
+    if (!pGlyphs)
+        return nullptr;
+
+    // Remember the calculation result.
+    aTextGlyphs = *pGlyphs;
+
+    return &aTextGlyphs;
+}
+
 MenuItemList::~MenuItemList()
 {
 }