svgio visitor, add draw commands and create the from svg

Adds a visitor for svgio for visiting svg nodes and create something
useful from them.

Basic draw commands - a tree of draw commands (with sub-pixel
precision support) just to store a simple definition for drawing.

Adds a svg draw visitor and create draw commands from the svg
structure and expose the commands through UNO API.

Change-Id: I073e891a2cffdd76d4e3b838590e3a19c998e9bf
Reviewed-on: https://gerrit.libreoffice.org/68770
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

2 files changed, 53 insertions, 0 deletions

diff --git a/svgio/inc/svgnode.hxx b/svgio/inc/svgnode.hxx
index 22df883b22b3..c10179bf236a 100644
--- a/svgio/inc/svgnode.hxx
+++ b/svgio/inc/svgnode.hxx
@@ -80,6 +80,8 @@ namespace svgio
         // which members should be initialized
         Display getDisplayFromContent(const OUString& aContent);
 
+      class Visitor;
+
         class SvgNode : public InfoProvider
         {
         private:
@@ -137,6 +139,8 @@ namespace svgio
             SvgNode(const SvgNode&) = delete;
             SvgNode& operator=(const SvgNode&) = delete;
 
+            void accept(Visitor& rVisitor);
+
             /// scan helper to read and interpret a local CssStyle to mpLocalCssStyle
             void readLocalCssStyle(const OUString& aContent);
 
@@ -182,6 +186,14 @@ namespace svgio
             /// alternative parent
             void setAlternativeParent(const SvgNode* pAlternativeParent = nullptr) { mpAlternativeParent = pAlternativeParent; }
         };
+
+      class Visitor
+      {
+      public:
+            virtual ~Visitor() = default;
+            virtual void visit(SvgNode const & pNode) = 0;
+      };
+
     } // end of namespace svgreader
 } // end of namespace svgio
 
diff --git a/svgio/inc/svgvisitor.hxx b/svgio/inc/svgvisitor.hxx
new file mode 100644
index 000000000000..ea56e4cd189a
--- /dev/null
+++ b/svgio/inc/svgvisitor.hxx
@@ -0,0 +1,41 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ */
+
+#ifndef INCLUDED_SVGIO_INC_SVGVISITOR_HXX
+#define INCLUDED_SVGIO_INC_SVGVISITOR_HXX
+
+#include <basegfx/DrawCommands.hxx>
+#include <memory>
+#include "svgnode.hxx"
+
+namespace svgio
+{
+namespace svgreader
+{
+class SvgDrawVisitor : public Visitor
+{
+private:
+    std::shared_ptr<DrawRoot> mpDrawRoot;
+    std::shared_ptr<DrawBase> mpCurrent;
+
+public:
+    SvgDrawVisitor();
+
+    void visit(svgio::svgreader::SvgNode const& rNode) override;
+    void goToChildren(svgio::svgreader::SvgNode const& rNode);
+
+    std::shared_ptr<DrawRoot> const& getDrawRoot() { return mpDrawRoot; }
+};
+}
+}
+
+#endif // INCLUDED_SVGIO_INC_SVGVISITOR_HXX
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */