Replace SVGFilter using SVGIO

Next step is to put more logic into the decision
if Draw or Impress should be loaded - if we have a
self-exported Impress, import as Impress, else
(including all not-self-created SVG Graphics) import
to Draw.
To do this it is necessary to be able to import to
different document formats at all. To do this, add
an internal filter type to the filter mechanism
(types/registration/...) and decide in the SVG
XExtendedFilterDetection::detect from SVGFilter
which one to use.
Added tooling for SVG detection and more, see
SVGFileInfo. This allows to detect for SVG, but
also if the creator was LO and if it was Draw or
Impress. The document format/filter is choosen
accordingly.
Corrected the error with <g visibility="hidden">
Slides inisde <g class="SlideGroup"> for import
of self-exported Impress documents. No idea why
this was written that way, but needs to be fixed
to get a visible content at all.
Also adapted the final mapping from pt to 100thmm
in SvgSvgNode::decomposeSvgNode. Unfortunately
(and also for unknown reasons) the self-exported
Impress does not write svg:width/height values,
thus the adaption from assumed svg-units (px) to
100thmm has to be skipped.
Have identified the place in svgio where I can
embed Pages/Slides to a helper-Primitive to later
be able to 'break' such GraphicObjects to multiple
Pages/Slides. I have added a Primitive called
PageHierarchyPrimitive2D for this purpose.

Change-Id: I38bfef6e7b16479a025fc754e38b4e21a006ad38
Reviewed-on: https://gerrit.libreoffice.org/55434
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Armin Le Grand <Armin.Le.Grand@cib.de>

2 files changed, 104 insertions, 17 deletions

diff --git a/svgio/source/svgreader/svgstyleattributes.cxx b/svgio/source/svgreader/svgstyleattributes.cxx
index f1bc7c737aae..2d96cfb9d022 100644
--- a/svgio/source/svgreader/svgstyleattributes.cxx
+++ b/svgio/source/svgreader/svgstyleattributes.cxx
@@ -38,6 +38,7 @@
 #include <drawinglayer/primitive2d/patternfillprimitive2d.hxx>
 #include <basegfx/polygon/b2dpolygontools.hxx>
 #include <drawinglayer/primitive2d/maskprimitive2d.hxx>
+#include <drawinglayer/primitive2d/pagehierarchyprimitive2d.hxx>
 
 namespace svgio
 {
@@ -1196,13 +1197,48 @@ namespace svgio
                         // #i124852# transform may be needed when userSpaceOnUse
                         pMask->apply(aSource, pTransform);
                     }
+                }
+
+                // This is part of the SVG import of self-written SVGs from
+                // Draw/Impress containing multiple Slides/Pages. To be able
+                // to later 'break' these to multiple Pages if wanted, embed
+                // each Page-Content in a identifiable Primitive Grouping
+                // Object.
+                // This is the case when the current Node is a GroupNode, has
+                // class="Page" set, has a parent that also is a GroupNode
+                // at which class="Slide" is set.
+                // Multiple Slides/Pages are possible for Draw and Impress.
+                if(SVGTokenG == mrOwner.getType() && mrOwner.getClass())
+                {
+                    const OUString aOwnerClass(*mrOwner.getClass());
 
-                    if(!aSource.empty()) // test again, applied mask may have lead to empty geometry
+                    if("Page" == aOwnerClass)
                     {
-                        // append to current target
-                        rTarget.append(aSource);
+                        const SvgNode* pParent(mrOwner.getParent());
+
+                        if(nullptr != pParent && SVGTokenG == pParent->getType() && pParent->getClass())
+                        {
+                            const OUString aParentClass(*pParent->getClass());
+
+                            if("Slide" == aParentClass)
+                            {
+                                // embed to grouping primitive to identify the
+                                // Slide/Page information
+                                const drawinglayer::primitive2d::Primitive2DReference xRef(
+                                    new drawinglayer::primitive2d::PageHierarchyPrimitive2D(
+                                        aSource));
+
+                                aSource = drawinglayer::primitive2d::Primitive2DContainer { xRef };
+                            }
+                        }
                     }
                 }
+
+                if(!aSource.empty()) // test again, applied mask may have lead to empty geometry
+                {
+                    // append to current target
+                    rTarget.append(aSource);
+                }
             }
         }
 
@@ -2216,6 +2252,36 @@ namespace svgio
                 return Visibility_visible;
             }
 
+            // Visibility correction/exception for self-exported SVGs:
+            // When Impress exports single or multi-page SVGs, it puts the
+            // single slides into <g visibility="hidden">. Not sure why
+            // whis happens, but this leads (correctly) to empty imported
+            // Graphics.
+            // Thus, if Visibility_hidden is active and owner is a SVGTokenG
+            // and it's parent is also a SVGTokenG and it has a Class 'SlideGroup'
+            // set, check if we are an Impress export.
+            // We are an Impress export if an SVG-Node titled 'ooo:meta_slides'
+            // exists.
+            // All togehter gives:
+            if(Visibility_hidden == maVisibility
+                && SVGTokenG == mrOwner.getType()
+                && nullptr != mrOwner.getDocument().findSvgNodeById("ooo:meta_slides"))
+            {
+                const SvgNode* pParent(mrOwner.getParent());
+
+                if(nullptr != pParent && SVGTokenG == pParent->getType() && pParent->getClass())
+                {
+                    const OUString aClass(*pParent->getClass());
+
+                    if("SlideGroup" == aClass)
+                    {
+                        // if we detect this exception,
+                        // ovverride Visibility_hidden -> Visibility_visible
+                        return Visibility_visible;
+                    }
+                }
+            }
+
             return maVisibility;
         }
 
diff --git a/svgio/source/svgreader/svgsvgnode.cxx b/svgio/source/svgreader/svgsvgnode.cxx
index 40dfaca1a402..524e6d360030 100644
--- a/svgio/source/svgreader/svgsvgnode.cxx
+++ b/svgio/source/svgreader/svgsvgnode.cxx
@@ -26,6 +26,7 @@
 #include <basegfx/matrix/b2dhommatrixtools.hxx>
 #include <drawinglayer/primitive2d/polygonprimitive2d.hxx>
 #include <drawinglayer/primitive2d/hiddengeometryprimitive2d.hxx>
+#include <svgdocument.hxx>
 
 namespace svgio
 {
@@ -670,21 +671,41 @@ namespace svgio
 
                         if(!aSequence.empty())
                         {
-                            // embed in transform primitive to scale to 1/100th mm
-                            // where 1 inch == 25.4 mm to get from Svg coordinates (px) to
-                            // drawinglayer coordinates
-                            const double fScaleTo100thmm(25.4 * 100.0 / F_SVG_PIXEL_PER_INCH);
-                            const basegfx::B2DHomMatrix aTransform(
-                                basegfx::utils::createScaleB2DHomMatrix(
-                                    fScaleTo100thmm,
-                                    fScaleTo100thmm));
-
-                            const drawinglayer::primitive2d::Primitive2DReference xTransform(
-                                new drawinglayer::primitive2d::TransformPrimitive2D(
-                                    aTransform,
-                                    aSequence));
+                            // Another correction:
+                            // If no Width/Height is set (usually done in
+                            // <svg ... width="215.9mm" height="279.4mm" >) which
+                            // is the case for own-Impress-exports, assume that
+                            // the Units are alrteady 100ThMM.
+                            // Maybe only for own-Impress-exports, thus may need to be
+                            // &&ed with getDocument().findSvgNodeById("ooo:meta_slides"),
+                            // but does not need to be.
+                            bool bEmbedInFinalTransformPxTo100ThMM(true);
+
+                            if(getDocument().findSvgNodeById("ooo:meta_slides")
+                                && !getWidth().isSet()
+                                && !getHeight().isSet())
+                            {
+                                bEmbedInFinalTransformPxTo100ThMM = false;
+                            }
+
+                            if(bEmbedInFinalTransformPxTo100ThMM)
+                            {
+                                // embed in transform primitive to scale to 1/100th mm
+                                // where 1 inch == 25.4 mm to get from Svg coordinates (px) to
+                                // drawinglayer coordinates
+                                const double fScaleTo100thmm(25.4 * 100.0 / F_SVG_PIXEL_PER_INCH);
+                                const basegfx::B2DHomMatrix aTransform(
+                                    basegfx::utils::createScaleB2DHomMatrix(
+                                        fScaleTo100thmm,
+                                        fScaleTo100thmm));
+
+                                const drawinglayer::primitive2d::Primitive2DReference xTransform(
+                                    new drawinglayer::primitive2d::TransformPrimitive2D(
+                                        aTransform,
+                                        aSequence));
 
-                            aSequence = drawinglayer::primitive2d::Primitive2DContainer { xTransform };
+                                aSequence = drawinglayer::primitive2d::Primitive2DContainer { xTransform };
+                            }
 
                             // append to result
                             rTarget.append(aSequence);