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

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 * This file incorporates work covered by the following license notice:

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#include <drawinglayer/primitive2d/shadowprimitive2d.hxx>

#include <basegfx/color/bcolormodifier.hxx>

#include <drawinglayer/primitive2d/modifiedcolorprimitive2d.hxx>

#include <drawinglayer/primitive2d/transformprimitive2d.hxx>

#include <drawinglayer/primitive2d/drawinglayer_primitivetypes2d.hxx>

#include <basegfx/matrix/b2dhommatrixtools.hxx>

#include <drawinglayer/primitive2d/bitmapprimitive2d.hxx>

#include <toolkit/helper/vclunohelper.hxx>

#include <drawinglayer/converters.hxx>

#include "GlowSoftEgdeShadowTools.hxx"

#ifdef DBG_UTIL

#include <tools/stream.hxx>

#include <vcl/filter/PngImageWriter.hxx>

#endif

#include <memory>

#include <utility>

using namespace com::sun::star;

namespace drawinglayer::primitive2d

{

ShadowPrimitive2D::ShadowPrimitive2D(basegfx::B2DHomMatrix aShadowTransform,

                                     const basegfx::BColor& rShadowColor, double fShadowBlur,

                                     Primitive2DContainer&& aChildren)

    : BufferedDecompositionGroupPrimitive2D(std::move(aChildren))

    , maShadowTransform(std::move(aShadowTransform))

    , maShadowColor(rShadowColor)

    , mfShadowBlur(fShadowBlur)

    , mfLastDiscreteBlurRadius(0.0)

    , maLastClippedRange()

{

    // activate callback to flush buffered decomposition content

    activateFlushOnTimer();

}

bool ShadowPrimitive2D::operator==(const BasePrimitive2D& rPrimitive) const

{

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

    {

        const ShadowPrimitive2D& rCompare = static_cast<const ShadowPrimitive2D&>(rPrimitive);

        return (getShadowTransform() == rCompare.getShadowTransform()

                && getShadowColor() == rCompare.getShadowColor()

                && getShadowBlur() == rCompare.getShadowBlur());

    }

    return false;

}

// Helper to get the to-be-shadowed geometry completely embedded to

// a ModifiedColorPrimitive2D (change to ShadowColor) and TransformPrimitive2D

// (direction/offset/transformation of shadow). Since this is used pretty

// often, pack into a helper

void ShadowPrimitive2D::getFullyEmbeddedShadowPrimitives(Primitive2DContainer& rContainer) const

{

    if (getChildren().empty())

        return;

    // create a modifiedColorPrimitive containing the shadow color and the content

    const basegfx::BColorModifierSharedPtr aBColorModifier

        = std::make_shared<basegfx::BColorModifier_replace>(getShadowColor());

    const Primitive2DReference xRefA(

        new ModifiedColorPrimitive2D(Primitive2DContainer(getChildren()), aBColorModifier));

    Primitive2DContainer aSequenceB{ xRefA };

    // build transformed primitiveVector with shadow offset and add to target

    rContainer.visit(new TransformPrimitive2D(getShadowTransform(), std::move(aSequenceB)));

}

bool ShadowPrimitive2D::prepareValuesAndcheckValidity(

    basegfx::B2DRange& rBlurRange, basegfx::B2DRange& rClippedRange,

    basegfx::B2DVector& rDiscreteBlurSize, double& rfDiscreteBlurRadius,

    const geometry::ViewInformation2D& rViewInformation) const

{

    // no BlurRadius defined, done

    if (getShadowBlur() <= 0.0)

        return false;

    // no geometry, done

    if (getChildren().empty())

        return false;

    // no pixel target, done

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

        return false;

    // get fully embedded ShadowPrimitive

    Primitive2DContainer aEmbedded;

    getFullyEmbeddedShadowPrimitives(aEmbedded);

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

    rBlurRange = aEmbedded.getB2DRange(rViewInformation);

    // no range of geometry, done

    if (rBlurRange.isEmpty())

        return false;

    // extend range by BlurRadius in all directions

    rBlurRange.grow(getShadowBlur());

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

    rClippedRange = rBlurRange;

    // 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 BlurRadius to ensure needed parts are included

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

        aVisibleArea.grow(getShadowBlur());

        // calculate ClippedRange

        rClippedRange.intersect(aVisibleArea);

        // if BlurRange is completely outside of VisibleArea, ClippedRange

        // will be empty and we are done

        if (rClippedRange.isEmpty())

            return false;

    }

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

    rDiscreteBlurSize = rViewInformation.getObjectToViewTransformation() * rBlurRange.getRange();

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

        return false;

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

    rfDiscreteBlurRadius = ceil(

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

            .getLength());

    if (rfDiscreteBlurRadius < 1.0)

        return false;

    return true;

}

void ShadowPrimitive2D::create2DDecomposition(

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

{

    if (getShadowBlur() <= 0.0)

    {

        // Normal (non-blurred) shadow is already completely

        // handled by get2DDecomposition and not buffered. It

        // does not need to be since it's a simple embedding

        // to a ModifiedColorPrimitive2D and TransformPrimitive2D

        return;

    }

    // from here on we process a blurred shadow

    basegfx::B2DRange aBlurRange;

    basegfx::B2DRange aClippedRange;

    basegfx::B2DVector aDiscreteBlurSize;

    double fDiscreteBlurRadius(0.0);

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

    if (!prepareValuesAndcheckValidity(aBlurRange, aClippedRange, aDiscreteBlurSize,

                                       fDiscreteBlurRadius, rViewInformation))

        return;

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

    // target pixel geometry (discrete form of ClippedRange)

    // First, move to top-left of BlurRange

    const sal_uInt32 nDiscreteBlurWidth(ceil(aDiscreteBlurSize.getX()));

    const sal_uInt32 nDiscreteBlurHeight(ceil(aDiscreteBlurSize.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 BlurRange

    aEmbedding.scale(nDiscreteBlurWidth / aBlurRange.getWidth(),

                     nDiscreteBlurHeight / aBlurRange.getHeight());

    // Get fully embedded ShadowPrimitives. This will also embed to

    // ModifiedColorPrimitive2D (what is not urgently needed) to create

    // the alpha channel, but a paint with all colors set to a single

    // one (like shadowColor here) is often less expensive due to possible

    // simplifications painting the primitives (e.g. gradient)

    Primitive2DContainer aEmbedded;

    getFullyEmbeddedShadowPrimitives(aEmbedded);

    // Embed content graphics to TransformPrimitive2D

    const primitive2d::Primitive2DReference xEmbedRef(

        new primitive2d::TransformPrimitive2D(aEmbedding, std::move(aEmbedded)));

    primitive2d::Primitive2DContainer xEmbedSeq{ xEmbedRef };

    // Create BitmapEx 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 Blurred Shadow 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);

    // I have now added a helper that just creates the mask without having

    // to render the content, use it, it's faster

    const AlphaMask aAlpha(::drawinglayer::createAlphaMask(

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

        nMaximumQuadraticPixels));

    // if we have no shadow, we are done

    if (aAlpha.IsEmpty())

        return;

    const Size aBitmapExSizePixel(aAlpha.GetSizePixel());

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

        return;

    // 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>(aBitmapExSizePixel.Width()) != nDiscreteClippedWidth

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

    {

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

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

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

                             / static_cast<double>(nDiscreteClippedWidth));

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

                             / static_cast<double>(nDiscreteClippedHeight));

        fScale = (fScaleX + fScaleY) * 0.5;

    }

    // Use the Alpha as base to blur and apply the effect

    const AlphaMask mask(drawinglayer::primitive2d::ProcessAndBlurAlphaMask(

        aAlpha, 0, fDiscreteBlurRadius * fScale, 0, false));

    // The end result is the bitmap filled with blur color and blurred 8-bit alpha mask

    Bitmap bmp(aAlpha.GetSizePixel(), vcl::PixelFormat::N24_BPP);

    bmp.Erase(Color(getShadowColor()));

    BitmapEx result(bmp, mask);

#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(

            OUString::createFromAscii(std::getenv("VCL_DUMP_BMP_PATH")));

        if (!sDumpPath.isEmpty())

        {

            SvFileStream aNew(sDumpPath + "test_shadowblur.png",

                              StreamMode::WRITE | StreamMode::TRUNC);

            vcl::PngImageWriter aPNGWriter(aNew);

            aPNGWriter.write(result);

        }

    }

#endif

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

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

    // 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 };

}

void ShadowPrimitive2D::get2DDecomposition(

    Primitive2DDecompositionVisitor& rVisitor,

    const geometry::ViewInformation2D& rViewInformation) const

{

    if (getShadowBlur() <= 0.0)

    {

        // normal (non-blurred) shadow

        if (getChildren().empty())

            return;

        // get fully embedded ShadowPrimitives

        Primitive2DContainer aEmbedded;

        getFullyEmbeddedShadowPrimitives(aEmbedded);

        rVisitor.visit(aEmbedded);

        return;

    }

    // here we have a blurred shadow, check conditions of last

    // buffered decompose and decide re-use or re-create by using

    // setBuffered2DDecomposition to reset local buffered version

    basegfx::B2DRange aBlurRange;

    basegfx::B2DRange aClippedRange;

    basegfx::B2DVector aDiscreteBlurSize;

    double fDiscreteBlurRadius(0.0);

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

    if (!prepareValuesAndcheckValidity(aBlurRange, aClippedRange, aDiscreteBlurSize,

                                       fDiscreteBlurRadius, rViewInformation))

        return;

    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<ShadowPrimitive2D*>(this)->setBuffered2DDecomposition(

                    Primitive2DContainer());

            }

        }

    }

    if (hasBuffered2DDecomposition())

    {

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

        // zooming in/out (see similar implementation at ShadowPrimitive2D).

        bool bFree(mfLastDiscreteBlurRadius <= 0.0 || fDiscreteBlurRadius <= 0.0);

        if (!bFree)

        {

            const double fDiff(fabs(mfLastDiscreteBlurRadius - fDiscreteBlurRadius));

            const double fLen(fabs(mfLastDiscreteBlurRadius) + fabs(fDiscreteBlurRadius));

            const double fRelativeChange(fDiff / fLen);

            // Use lower fixed values here to change more often, higher to change less often.

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

            bFree = fRelativeChange >= 0.15;

        }

        if (bFree)

        {

            // Conditions of last local decomposition have changed, delete

            const_cast<ShadowPrimitive2D*>(this)->setBuffered2DDecomposition(

                Primitive2DContainer());

        }

    }

    if (!hasBuffered2DDecomposition())

    {

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

        const_cast<ShadowPrimitive2D*>(this)->mfLastDiscreteBlurRadius = fDiscreteBlurRadius;

        const_cast<ShadowPrimitive2D*>(this)->maLastClippedRange = aClippedRange;

    }

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

    // set as decomposition

    BufferedDecompositionGroupPrimitive2D::get2DDecomposition(rVisitor, rViewInformation);

}

basegfx::B2DRange

ShadowPrimitive2D::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.

    basegfx::B2DRange aRetval(getChildren().getB2DRange(rViewInformation));

    if (getShadowBlur() > 0.0)

    {

        // blurred shadow, that extends the geometry

        aRetval.grow(getShadowBlur());

    }

    aRetval.transform(getShadowTransform());

    return aRetval;

}

// provide unique ID

sal_uInt32 ShadowPrimitive2D::getPrimitive2DID() const { return PRIMITIVE2D_ID_SHADOWPRIMITIVE2D; }

} // end of namespace

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