make SalLayoutGlyphs work with MultiSalLayout

Code that needs to lay out texts repeatedly can cache the result
of SalLayout::GetGlyphs() can reuse it. But GetGlyphs() returns
nullptr for MultiSalLayout, so caching for it doesn't work. Worse
still, it actually increases the number of layout calls, because
there's the initial layout for caching and then each call
will need to do the layout again because of the nullptr that's
not cached.

This commit changes SalLayoutGlyphs to possibly include multiple
SalLayoutGlyphsImpl objects, one for each SalLayout handled
by MultiSalLayout. Changes include making GenericSalLayout
work directly with the Impl class, which avoids an indirection
and simplifies code.

Change-Id: Ic4b19934a8a06d4955b51527fe3777c5e91107b2
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/112590
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>

1 files changed, 1 insertions, 5 deletions

diff --git a/svtools/source/control/ruler.cxx b/svtools/source/control/ruler.cxx
index 1f4a5d4eafac..2551dc39581d 100644
--- a/svtools/source/control/ruler.cxx
+++ b/svtools/source/control/ruler.cxx
@@ -84,12 +84,8 @@ SalLayoutGlyphs* lcl_GetRulerTextGlyphs(const vcl::RenderContext& rRenderContext
     if (!pLayout)
         return nullptr;
 
-    const SalLayoutGlyphs* pGlyphs = pLayout->GetGlyphs();
-    if (!pGlyphs)
-        return nullptr;
-
     // Remember the calculation result.
-    rTextGlyphs = *pGlyphs;
+    rTextGlyphs = pLayout->GetGlyphs();
 
     return &rTextGlyphs;
 }