xref: /aoo42x/main/drawinglayer/source/primitive2d/unifiedtransparenceprimitive2d.cxx (revision 4bfbcde8)

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// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_drawinglayer.hxx"

#include <drawinglayer/primitive2d/unifiedtransparenceprimitive2d.hxx>
#include <basegfx/polygon/b2dpolygon.hxx>
#include <basegfx/polygon/b2dpolygontools.hxx>
#include <basegfx/color/bcolor.hxx>
#include <drawinglayer/primitive2d/polypolygonprimitive2d.hxx>
#include <drawinglayer/primitive2d/transparenceprimitive2d.hxx>
#include <drawinglayer/primitive2d/drawinglayer_primitivetypes2d.hxx>
#include <drawinglayer/primitive2d/polygonprimitive2d.hxx>

//////////////////////////////////////////////////////////////////////////////

using namespace com::sun::star;

//////////////////////////////////////////////////////////////////////////////

namespace drawinglayer
{
	namespace primitive2d
	{
		UnifiedTransparencePrimitive2D::UnifiedTransparencePrimitive2D(
			const Primitive2DSequence& rChildren,
			double fTransparence)
		:	GroupPrimitive2D(rChildren),
			mfTransparence(fTransparence)
		{
		}

		bool UnifiedTransparencePrimitive2D::operator==(const BasePrimitive2D& rPrimitive) const
		{
			if(GroupPrimitive2D::operator==(rPrimitive))
			{
				const UnifiedTransparencePrimitive2D& rCompare = (UnifiedTransparencePrimitive2D&)rPrimitive;

				return (getTransparence() == rCompare.getTransparence());
			}

			return false;
		}

		basegfx::B2DRange UnifiedTransparencePrimitive2D::getB2DRange(const geometry::ViewInformation2D& rViewInformation) const
        {
            // do not use the fallback to decomposition here since for a correct BoundRect we also
            // need invisible (1.0 == getTransparence()) geometry; these would be deleted in the decomposition
			return getB2DRangeFromPrimitive2DSequence(getChildren(), rViewInformation);
        }

		Primitive2DSequence UnifiedTransparencePrimitive2D::get2DDecomposition(const geometry::ViewInformation2D& rViewInformation) const
		{
			if(0.0 == getTransparence())
			{
				// no transparence used, so just use the content
				return getChildren();
			}
			else if(getTransparence() > 0.0 && getTransparence() < 1.0)
			{
                // The idea is to create a TransparencePrimitive2D with transparent content using a fill color
                // corresponding to the transparence value. Problem is that in most systems, the right
                // and bottom pixel array is not filled when filling polygons, thus this would not
                // always produce a complete transparent bitmap. There are some solutions:
                //
                // - Grow the used polygon range by one discrete unit in X and Y. This
                // will make the decomposition view-dependent.
                //
                // - For all filled polygon renderings, dra wthe polygon outline extra. This
                // would lead to unwanted side effects when using concatenated polygons.
                //
                // - At this decomposition, add a filled polygon and a hairline polygon. This
                // solution stays view-independent.
                //
                // I will take the last one here. The small overhead of two primitives will only be
                // used when UnifiedTransparencePrimitive2D is not handled directly.
				const basegfx::B2DRange aPolygonRange(getB2DRangeFromPrimitive2DSequence(getChildren(), rViewInformation));
				const basegfx::B2DPolygon aPolygon(basegfx::tools::createPolygonFromRect(aPolygonRange));
				const basegfx::BColor aGray(getTransparence(), getTransparence(), getTransparence());
				Primitive2DSequence aTransparenceContent(2);

                aTransparenceContent[0] = Primitive2DReference(new PolyPolygonColorPrimitive2D(basegfx::B2DPolyPolygon(aPolygon), aGray));
                aTransparenceContent[1] = Primitive2DReference(new PolygonHairlinePrimitive2D(aPolygon, aGray));

				// create sub-transparence group with a gray-colored rectangular fill polygon
				const Primitive2DReference xRefB(new TransparencePrimitive2D(getChildren(), aTransparenceContent));
				return Primitive2DSequence(&xRefB, 1L);
			}
			else
			{
				// completely transparent or invalid definition, add nothing
				return Primitive2DSequence();
			}
		}

		// provide unique ID
		ImplPrimitrive2DIDBlock(UnifiedTransparencePrimitive2D, PRIMITIVE2D_ID_UNIFIEDTRANSPARENCEPRIMITIVE2D)

	} // end of namespace primitive2d
} // end of namespace drawinglayer

//////////////////////////////////////////////////////////////////////////////
// eof