/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

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#include <drawinglayer/primitive2d/drawinglayer_primitivetypes2d.hxx>

#include <drawinglayer/primitive2d/softedgeprimitive2d.hxx>

#include <drawinglayer/primitive2d/transformprimitive2d.hxx>

#include <drawinglayer/primitive2d/bitmapprimitive2d.hxx>

#include <basegfx/matrix/b2dhommatrixtools.hxx>

#include <drawinglayer/converters.hxx>

#include "GlowSoftEgdeShadowTools.hxx"

#ifdef DBG_UTIL

#include <o3tl/environment.hxx>

#include <tools/stream.hxx>

#include <vcl/filter/PngImageWriter.hxx>

#endif

namespace drawinglayer::primitive2d

{

SoftEdgePrimitive2D::SoftEdgePrimitive2D(double fRadius, Primitive2DContainer&& aChildren)

    : BufferedDecompositionGroupPrimitive2D(std::move(aChildren))

    , mfRadius(fRadius)

    , mfLastDiscreteSoftRadius(0.0)

    , maLastClippedRange()

{

    // activate callback to flush buffered decomposition content

    activateFlushOnTimer();

}

bool SoftEdgePrimitive2D::operator==(const BasePrimitive2D& rPrimitive) const

{

    if (BufferedDecompositionGroupPrimitive2D::operator==(rPrimitive))

    {

        auto& rCompare = static_cast<const SoftEdgePrimitive2D&>(rPrimitive);

        return getRadius() == rCompare.getRadius();

    }

    return false;

}

bool SoftEdgePrimitive2D::prepareValuesAndcheckValidity(

    basegfx::B2DRange& rSoftRange, basegfx::B2DRange& rClippedRange,

    basegfx::B2DVector& rDiscreteSoftSize, double& rfDiscreteSoftRadius,

    const geometry::ViewInformation2D& rViewInformation) const

{

    // no SoftRadius defined, done

    if (getRadius() <= 0.0)

        return false;

    // no geometry, done

    if (getChildren().empty())

        return false;

    // no pixel target, done

    if (rViewInformation.getObjectToViewTransformation().isIdentity())

        return false;

    // get geometry range that defines area that needs to be pixelated

    rSoftRange = getChildren().getB2DRange(rViewInformation);

    // no range of geometry, done

    if (rSoftRange.isEmpty())

        return false;

    // initialize ClippedRange to full SoftRange -> all is visible

    rClippedRange = rSoftRange;

    // get Viewport and check if used. If empty, all is visible (see

    // ViewInformation2D definition in viewinformation2d.hxx)

    if (!rViewInformation.getViewport().isEmpty())

    {

        // if used, extend by SoftRadius to ensure needed parts are included

        // that are not visible, but influence the visible parts

        basegfx::B2DRange aVisibleArea(rViewInformation.getViewport());

        aVisibleArea.grow(getRadius() * 2);

        // To do this correctly, it needs to be done in discrete coordinates.

        // The object may be transformed relative to the original#

        // ObjectTransformation, e.g. when re-used in shadow

        aVisibleArea.transform(rViewInformation.getViewTransformation());

        rClippedRange.transform(rViewInformation.getObjectToViewTransformation());

        // calculate ClippedRange

        rClippedRange.intersect(aVisibleArea);

        // if SoftRange is completely outside of VisibleArea, ClippedRange

        // will be empty and we are done

        if (rClippedRange.isEmpty())

            return false;

        // convert result back to object coordinates

        rClippedRange.transform(rViewInformation.getInverseObjectToViewTransformation());

    }

    // calculate discrete pixel size of SoftRange. If it's too small to visualize, we are done

    rDiscreteSoftSize = rViewInformation.getObjectToViewTransformation() * rSoftRange.getRange();

    if (ceil(rDiscreteSoftSize.getX()) < 2.0 || ceil(rDiscreteSoftSize.getY()) < 2.0)

        return false;

    // calculate discrete pixel size of SoftRadius. If it's too small to visualize, we are done

    rfDiscreteSoftRadius = ceil(

        (rViewInformation.getObjectToViewTransformation() * basegfx::B2DVector(getRadius(), 0))

            .getLength());

    if (rfDiscreteSoftRadius < 1.0)

        return false;

    return true;

}

void SoftEdgePrimitive2D::create2DDecomposition(

    Primitive2DContainer& rContainer, const geometry::ViewInformation2D& rViewInformation) const

{

    // Use endless while-loop-and-break mechanism due to having multiple

    // exit scenarios that all have to do the same thing when exiting

    while (true)

    {

        basegfx::B2DRange aSoftRange;

        basegfx::B2DRange aClippedRange;

        basegfx::B2DVector aDiscreteSoftSize;

        double fDiscreteSoftRadius(0.0);

        // Check various validity details and calculate/prepare values. If false, we are done

        if (!prepareValuesAndcheckValidity(aSoftRange, aClippedRange, aDiscreteSoftSize,

                                           fDiscreteSoftRadius, rViewInformation))

            break;

        // Create embedding transformation from object to top-left zero-aligned

        // target pixel geometry (discrete form of ClippedRange)

        // First, move to top-left of SoftRange

        const sal_uInt32 nDiscreteSoftWidth(ceil(aDiscreteSoftSize.getX()));

        const sal_uInt32 nDiscreteSoftHeight(ceil(aDiscreteSoftSize.getY()));

        basegfx::B2DHomMatrix aEmbedding(basegfx::utils::createTranslateB2DHomMatrix(

            -aClippedRange.getMinX(), -aClippedRange.getMinY()));

        // Second, scale to discrete bitmap size

        // Even when using the offset from ClippedRange, we need to use the

        // scaling from the full representation, thus from SoftRange

        aEmbedding.scale(nDiscreteSoftWidth / aSoftRange.getWidth(),

                         nDiscreteSoftHeight / aSoftRange.getHeight());

        // Embed content graphics to TransformPrimitive2D

        const primitive2d::Primitive2DReference xEmbedRef(

            new primitive2d::TransformPrimitive2D(aEmbedding, Primitive2DContainer(getChildren())));

        primitive2d::Primitive2DContainer xEmbedSeq{ xEmbedRef };

        // Create Bitmap using drawinglayer tooling, including a MaximumQuadraticPixel

        // limitation to be safe and not go runtime/memory havoc. Use a pretty small

        // limit due to this is softEdge functionality and will look good with bitmap scaling

        // anyways. The value of 250.000 square pixels below maybe adapted as needed.

        const basegfx::B2DVector aDiscreteClippedSize(

            rViewInformation.getObjectToViewTransformation() * aClippedRange.getRange());

        const sal_uInt32 nDiscreteClippedWidth(ceil(aDiscreteClippedSize.getX()));

        const sal_uInt32 nDiscreteClippedHeight(ceil(aDiscreteClippedSize.getY()));

        const geometry::ViewInformation2D aViewInformation2D;

        const sal_uInt32 nMaximumQuadraticPixels(250000);

        // tdf#156808 force an alpha mask to be created even if it has no alpha

        // We need an alpha mask, even if it is totally opaque, so that

        // drawinglayer::primitive2d::ProcessAndBlurAlphaMask() can be called.

        // Otherwise, blurring of edges will fail in cases like running in a

        // slideshow or exporting to PDF.

        const Bitmap aBitmap(::drawinglayer::convertToBitmap(

            std::move(xEmbedSeq), aViewInformation2D, nDiscreteClippedWidth, nDiscreteClippedHeight,

            nMaximumQuadraticPixels, true));

        if (aBitmap.IsEmpty())

            break;

        // Get Bitmap and check size. If no content, we are done

        const Size aBitmapSizePixel(aBitmap.GetSizePixel());

        if (!(aBitmapSizePixel.Width() > 0 && aBitmapSizePixel.Height() > 0))

            break;

        // We may have to take a corrective scaling into account when the

        // MaximumQuadraticPixel limit was used/triggered

        double fScale(1.0);

        if (static_cast<sal_uInt32>(aBitmapSizePixel.Width()) != nDiscreteClippedWidth

            || static_cast<sal_uInt32>(aBitmapSizePixel.Height()) != nDiscreteClippedHeight)

        {

            // scale in X and Y should be the same (see fReduceFactor in convertToBitmapEx),

            // so adapt numerically to a single scale value, they are integer rounded values

            const double fScaleX(static_cast<double>(aBitmapSizePixel.Width())

                                 / static_cast<double>(nDiscreteClippedWidth));

            const double fScaleY(static_cast<double>(aBitmapSizePixel.Height())

                                 / static_cast<double>(nDiscreteClippedHeight));

            fScale = (fScaleX + fScaleY) * 0.5;

        }

        // Get the Alpha and use as base to blur and apply the effect

        AlphaMask aMask(aBitmap.CreateAlphaMask());

        if (aMask.IsEmpty()) // There is no mask, fully opaque

            break;

        AlphaMask blurMask(drawinglayer::primitive2d::ProcessAndBlurAlphaMask(

            aMask, -fDiscreteSoftRadius * fScale, fDiscreteSoftRadius * fScale, 0));

        aMask.BlendWith(blurMask);

        // The end result is the original bitmap with blurred 8-bit alpha mask

        Bitmap result(aBitmap.CreateColorBitmap(), aMask);

#ifdef DBG_UTIL

        static bool bDoSaveForVisualControl(false); // loplugin:constvars:ignore

        if (bDoSaveForVisualControl)

        {

            // VCL_DUMP_BMP_PATH should be like C:/path/ or ~/path/

            static const OUString sDumpPath(o3tl::getEnvironment(u"VCL_DUMP_BMP_PATH"_ustr));

            if (!sDumpPath.isEmpty())

            {

                SvFileStream aNew(sDumpPath + "test_softedge.png",

                                  StreamMode::WRITE | StreamMode::TRUNC);

                vcl::PngImageWriter aPNGWriter(aNew);

                aPNGWriter.write(result);

            }

        }

#endif

        // Independent from discrete sizes of soft alpha creation, always

        // map and project soft result to geometry range extended by soft

        // radius, but to the eventually clipped instance (ClippedRange)

        const primitive2d::Primitive2DReference xEmbedRefBitmap(

            new BitmapPrimitive2D(result, basegfx::utils::createScaleTranslateB2DHomMatrix(

                                              aClippedRange.getWidth(), aClippedRange.getHeight(),

                                              aClippedRange.getMinX(), aClippedRange.getMinY())));

        rContainer = primitive2d::Primitive2DContainer{ xEmbedRefBitmap };

        // we made it, return

        return;

    }

    // creation failed for some of many possible reasons, use original

    // content, so the unmodified original geometry will be the result,

    // just without any softEdge effect

    rContainer = getChildren();

}

void SoftEdgePrimitive2D::get2DDecomposition(

    Primitive2DDecompositionVisitor& rVisitor,

    const geometry::ViewInformation2D& rViewInformation) const

{

    // Use endless while-loop-and-break mechanism due to having multiple

    // exit scenarios that all have to do the same thing when exiting

    while (true)

    {

        basegfx::B2DRange aSoftRange;

        basegfx::B2DRange aClippedRange;

        basegfx::B2DVector aDiscreteSoftSize;

        double fDiscreteSoftRadius(0.0);

        // Check various validity details and calculate/prepare values. If false, we are done

        if (!prepareValuesAndcheckValidity(aSoftRange, aClippedRange, aDiscreteSoftSize,

                                           fDiscreteSoftRadius, rViewInformation))

            break;

        if (hasBuffered2DDecomposition())

        {

            // First check is to detect if the last created decompose is capable

            // to represent the now requested visualization (see similar

            // implementation at GlowPrimitive2D).

            if (!maLastClippedRange.isEmpty() && !maLastClippedRange.isInside(aClippedRange))

            {

                basegfx::B2DRange aLastClippedRangeAndHairline(maLastClippedRange);

                if (!rViewInformation.getObjectToViewTransformation().isIdentity())

                {

                    // Grow by view-dependent size of 1/2 pixel

                    const double fHalfPixel((rViewInformation.getInverseObjectToViewTransformation()

                                             * basegfx::B2DVector(0.5, 0))

                                                .getLength());

                    aLastClippedRangeAndHairline.grow(fHalfPixel);

                }

                if (!aLastClippedRangeAndHairline.isInside(aClippedRange))

                {

                    // Conditions of last local decomposition have changed, delete

                    const_cast<SoftEdgePrimitive2D*>(this)->setBuffered2DDecomposition(

                        Primitive2DContainer());

                }

            }

        }

        if (hasBuffered2DDecomposition())

        {

            // Second check is to react on changes of the DiscreteSoftRadius when

            // zooming in/out (see similar implementation at GlowPrimitive2D).

            bool bFree(mfLastDiscreteSoftRadius <= 0.0 || fDiscreteSoftRadius <= 0.0);

            if (!bFree)

            {

                const double fDiff(fabs(mfLastDiscreteSoftRadius - fDiscreteSoftRadius));

                const double fLen(fabs(mfLastDiscreteSoftRadius) + fabs(fDiscreteSoftRadius));

                const double fRelativeChange(fDiff / fLen);

                // Use a lower value here, soft edge keeps it's content so avoid that it gets too

                // unsharp in the pixel visualization

                // Value is in the range of ]0.0 .. 1.0]

                bFree = fRelativeChange >= 0.075;

            }

            if (bFree)

            {

                // Conditions of last local decomposition have changed, delete

                const_cast<SoftEdgePrimitive2D*>(this)->setBuffered2DDecomposition(

                    Primitive2DContainer());

            }

        }

        if (!hasBuffered2DDecomposition())

        {

            // refresh last used DiscreteSoftRadius and ClippedRange to new remembered values

            const_cast<SoftEdgePrimitive2D*>(this)->mfLastDiscreteSoftRadius = fDiscreteSoftRadius;

            const_cast<SoftEdgePrimitive2D*>(this)->maLastClippedRange = aClippedRange;

        }

        // call parent, that will check for empty, call create2DDecomposition and

        // set as decomposition

        BufferedDecompositionGroupPrimitive2D::get2DDecomposition(rVisitor, rViewInformation);

        // we made it, return

        return;

    }

    // No soft edge needed for some of many possible reasons, use original content

    rVisitor.visit(getChildren());

}

basegfx::B2DRange

SoftEdgePrimitive2D::getB2DRange(const geometry::ViewInformation2D& rViewInformation) const

{

    // Hint: Do *not* use GroupPrimitive2D::getB2DRange, that will (unnecessarily)

    // use the decompose - what works, but is not needed here.

    // We know the to-be-visualized geometry and the radius it needs to be extended,

    // so simply calculate the exact needed range.

    return getChildren().getB2DRange(rViewInformation);

}

sal_uInt32 SoftEdgePrimitive2D::getPrimitive2DID() const

{

    return PRIMITIVE2D_ID_SOFTEDGEPRIMITIVE2D;

}

} // end of namespace

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