office-gobmx/svgio/source/svgreader/svgclippathnode.cxx
Xisco Fauli 242b7d0162 svgio: simplify code
Change-Id: I100256b63fadeb4a0e4b8e4cbb67e58d2a1ce433
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/137096
Tested-by: Jenkins
Reviewed-by: Xisco Fauli <xiscofauli@libreoffice.org>
2022-07-15 10:38:08 +02:00

260 lines
10 KiB
C++

/* -*- 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/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#include <svgclippathnode.hxx>
#include <drawinglayer/primitive2d/transformprimitive2d.hxx>
#include <drawinglayer/primitive2d/maskprimitive2d.hxx>
#include <basegfx/matrix/b2dhommatrixtools.hxx>
#include <drawinglayer/geometry/viewinformation2d.hxx>
#include <drawinglayer/processor2d/contourextractor2d.hxx>
#include <basegfx/polygon/b2dpolypolygoncutter.hxx>
#include <basegfx/polygon/b2dpolygontools.hxx>
#include <o3tl/string_view.hxx>
namespace svgio::svgreader
{
SvgClipPathNode::SvgClipPathNode(
SvgDocument& rDocument,
SvgNode* pParent)
: SvgNode(SVGToken::ClipPathNode, rDocument, pParent),
maSvgStyleAttributes(*this),
maClipPathUnits(SvgUnits::userSpaceOnUse)
{
}
SvgClipPathNode::~SvgClipPathNode()
{
}
const SvgStyleAttributes* SvgClipPathNode::getSvgStyleAttributes() const
{
return &maSvgStyleAttributes;
}
void SvgClipPathNode::parseAttribute(const OUString& rTokenName, SVGToken aSVGToken, const OUString& aContent)
{
// call parent
SvgNode::parseAttribute(rTokenName, aSVGToken, aContent);
// read style attributes
maSvgStyleAttributes.parseStyleAttribute(aSVGToken, aContent);
// parse own
switch(aSVGToken)
{
case SVGToken::Style:
{
readLocalCssStyle(aContent);
break;
}
case SVGToken::Transform:
{
const basegfx::B2DHomMatrix aMatrix(readTransform(aContent, *this));
if(!aMatrix.isIdentity())
{
setTransform(aMatrix);
}
break;
}
case SVGToken::ClipPathUnits:
{
if(!aContent.isEmpty())
{
if(o3tl::equalsIgnoreAsciiCase(o3tl::trim(aContent), commonStrings::aStrUserSpaceOnUse))
{
setClipPathUnits(SvgUnits::userSpaceOnUse);
}
else if(o3tl::equalsIgnoreAsciiCase(o3tl::trim(aContent), commonStrings::aStrObjectBoundingBox))
{
setClipPathUnits(SvgUnits::objectBoundingBox);
}
}
break;
}
default:
{
break;
}
}
}
void SvgClipPathNode::decomposeSvgNode(drawinglayer::primitive2d::Primitive2DContainer& rTarget, bool bReferenced) const
{
drawinglayer::primitive2d::Primitive2DContainer aNewTarget;
// decompose children
SvgNode::decomposeSvgNode(aNewTarget, bReferenced);
if(aNewTarget.empty())
return;
if(getTransform())
{
// create embedding group element with transformation
const drawinglayer::primitive2d::Primitive2DReference xRef(
new drawinglayer::primitive2d::TransformPrimitive2D(
*getTransform(),
std::move(aNewTarget)));
rTarget.push_back(xRef);
}
else
{
// append to current target
rTarget.append(aNewTarget);
}
}
void SvgClipPathNode::apply(
drawinglayer::primitive2d::Primitive2DContainer& rContent,
const std::optional<basegfx::B2DHomMatrix>& pTransform) const
{
if (rContent.empty() || Display::None == getDisplay())
return;
const drawinglayer::geometry::ViewInformation2D aViewInformation2D;
drawinglayer::primitive2d::Primitive2DContainer aClipTarget;
basegfx::B2DPolyPolygon aClipPolyPolygon;
// get clipPath definition as primitives
decomposeSvgNode(aClipTarget, true);
if(!aClipTarget.empty())
{
// extract filled polygons as base for a mask PolyPolygon
drawinglayer::processor2d::ContourExtractor2D aExtractor(aViewInformation2D, true);
aExtractor.process(aClipTarget);
const basegfx::B2DPolyPolygonVector& rResult(aExtractor.getExtractedContour());
const sal_uInt32 nSize(rResult.size());
if(nSize > 1)
{
// merge to single clipPolyPolygon
aClipPolyPolygon = basegfx::utils::mergeToSinglePolyPolygon(rResult);
}
else
{
aClipPolyPolygon = rResult[0];
}
}
if(aClipPolyPolygon.count())
{
if (SvgUnits::objectBoundingBox == getClipPathUnits())
{
// clip is object-relative, transform using content transformation
const basegfx::B2DRange aContentRange(rContent.getB2DRange(aViewInformation2D));
aClipPolyPolygon.transform(
basegfx::utils::createScaleTranslateB2DHomMatrix(
aContentRange.getRange(),
aContentRange.getMinimum()));
}
else // userSpaceOnUse
{
// #i124852#
if(pTransform)
{
aClipPolyPolygon.transform(*pTransform);
}
}
// #i124313# try to avoid creating an embedding to a MaskPrimitive2D if
// possible; MaskPrimitive2D processing is potentially expensive
bool bCreateEmbedding(true);
bool bAddContent(true);
if(basegfx::utils::isRectangle(aClipPolyPolygon))
{
// ClipRegion is a rectangle, thus it is not expensive to tell
// if the content is completely inside or outside of it; get ranges
const basegfx::B2DRange aClipRange(aClipPolyPolygon.getB2DRange());
const basegfx::B2DRange aContentRange(
rContent.getB2DRange(
aViewInformation2D));
if(aClipRange.isInside(aContentRange))
{
// completely contained, no need to clip at all, so no need for embedding
bCreateEmbedding = false;
}
else if(aClipRange.overlaps(aContentRange))
{
// overlap; embedding needed. ClipRegion can be minimized by using
// the intersection of the ClipRange and the ContentRange. Minimizing
// the ClipRegion potentially enhances further processing since
// usually clip operations are expensive.
basegfx::B2DRange aCommonRange(aContentRange);
aCommonRange.intersect(aClipRange);
aClipPolyPolygon = basegfx::B2DPolyPolygon(basegfx::utils::createPolygonFromRect(aCommonRange));
}
else
{
// not inside and no overlap -> completely outside
// no need for embedding, no need for content at all
bCreateEmbedding = false;
bAddContent = false;
}
}
else
{
// ClipRegion is not a simple rectangle, it would be possible but expensive to
// tell if the content needs clipping or not. It is also dependent of
// the content's decomposition. To do this, a processor would be needed that
// is capable if processing the given sequence of primitives and decide
// if all is inside or all is outside. Such a ClipProcessor could be written,
// but for now just create the embedding
}
if(bCreateEmbedding)
{
// redefine target. Use MaskPrimitive2D with created clip
// geometry. Using the automatically set mbIsClipPathContent at
// SvgStyleAttributes the clip definition is without fill, stroke,
// and strokeWidth and forced to black
drawinglayer::primitive2d::Primitive2DReference xEmbedTransparence(
new drawinglayer::primitive2d::MaskPrimitive2D(
std::move(aClipPolyPolygon),
std::move(rContent)));
rContent = drawinglayer::primitive2d::Primitive2DContainer { xEmbedTransparence };
}
else
{
if(!bAddContent)
{
rContent.clear();
}
}
}
else
{
// An empty clipping path will completely clip away the element that had
// the clip-path property applied. (Svg spec)
rContent.clear();
}
}
} // end of namespace svgio::svgreader
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */