size some stringbuffer to prevent re-alloc

I started with 32 and kept doubling the size until the site
did not need re-alloc, but clamped it at 512 (e.g. in emfio/).

Change-Id: Ib7caf35a1b7e42b0e4ed8aa812493449e3eefc8f
Reviewed-on: https://gerrit.libreoffice.org/81540
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

1 files changed, 8 insertions, 1 deletions

diff --git a/basegfx/source/polygon/b2dsvgpolypolygon.cxx b/basegfx/source/polygon/b2dsvgpolypolygon.cxx
index 991e50bf60f0..2fdacad3653f 100644
--- a/basegfx/source/polygon/b2dsvgpolypolygon.cxx
+++ b/basegfx/source/polygon/b2dsvgpolypolygon.cxx
@@ -722,7 +722,14 @@ namespace basegfx
             bool bOOXMLMotionPath)
         {
             const sal_uInt32 nCount(rPolyPolygon.count());
-            OUStringBuffer aResult;
+            sal_uInt32 nCombinedPointCount = 0;
+            for(sal_uInt32 i(0); i < nCount; i++)
+            {
+                const B2DPolygon& aPolygon(rPolyPolygon.getB2DPolygon(i));
+                nCombinedPointCount += aPolygon.count();
+            }
+
+            OUStringBuffer aResult(std::max<int>(nCombinedPointCount * 32,512));
             B2DPoint aCurrentSVGPosition(0.0, 0.0); // SVG assumes (0,0) as the initial current point
 
             for(sal_uInt32 i(0); i < nCount; i++)