tdf#108037 Reduce time and memory consumed exporting to PDF

by avoiding making multiple copies of the Primitive2D container
that we pass to TransformPrimitive2D.
Instead, make TransformPrimitive2D store its children using a
GroupPrimitive2D, which means we can share the GroupPrimitive2D
among all the TransformPrimitive2D instances we create.

Change-Id: I8a4398f9db6a6ab013ee24ad53836975fba6f3df
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/162951
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

1 files changed, 6 insertions, 1 deletions

diff --git a/include/drawinglayer/primitive2d/transformprimitive2d.hxx b/include/drawinglayer/primitive2d/transformprimitive2d.hxx
index 73e589b8c2e8..8c3c22cc5b90 100644
--- a/include/drawinglayer/primitive2d/transformprimitive2d.hxx
+++ b/include/drawinglayer/primitive2d/transformprimitive2d.hxx
@@ -46,19 +46,24 @@ namespace drawinglayer::primitive2d
             different, transformed states without the need to create those
             thousand primitive contents.
          */
-        class DRAWINGLAYER_DLLPUBLIC TransformPrimitive2D final : public GroupPrimitive2D
+        class DRAWINGLAYER_DLLPUBLIC TransformPrimitive2D final : public BasePrimitive2D
         {
         private:
             // the transformation to apply to the child geometry
             basegfx::B2DHomMatrix                   maTransformation;
+            rtl::Reference<GroupPrimitive2D>        mxChildren;
 
         public:
             /// constructor
             TransformPrimitive2D(
                 basegfx::B2DHomMatrix aTransformation,
                 Primitive2DContainer&& rChildren);
+            TransformPrimitive2D(
+                basegfx::B2DHomMatrix aTransformation,
+                GroupPrimitive2D& rChildren);
 
             /// data read access
+            const Primitive2DContainer& getChildren() const { return mxChildren->getChildren(); }
             const basegfx::B2DHomMatrix& getTransformation() const { return maTransformation; }
 
             /// compare operator