glowprimitive2d.cxx

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#include <drawinglayer/primitive2d/glowprimitive2d.hxx>
#include <drawinglayer/primitive2d/transformprimitive2d.hxx>
#include <drawinglayer/primitive2d/drawinglayer_primitivetypes2d.hxx>
#include <drawinglayer/primitive2d/bitmapprimitive2d.hxx>
#include <basegfx/matrix/b2dhommatrixtools.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
 
using namespace com::sun::star;
 
namespace drawinglayer::primitive2d
{
GlowPrimitive2D::GlowPrimitive2D(const Color& rGlowColor, double fRadius,
                                 Primitive2DContainer&& rChildren)
    : BufferedDecompositionGroupPrimitive2D(std::move(rChildren))
    , maGlowColor(rGlowColor)
    , mfGlowRadius(fRadius)
    , mfLastDiscreteGlowRadius(0.0)
    , maLastClippedRange()
{
}
 
bool GlowPrimitive2D::operator==(const BasePrimitive2D& rPrimitive) const
{
    if (BufferedDecompositionGroupPrimitive2D::operator==(rPrimitive))
    {
        const GlowPrimitive2D& rCompare = static_cast<const GlowPrimitive2D&>(rPrimitive);
 
        return (getGlowRadius() == rCompare.getGlowRadius()
                && getGlowColor() == rCompare.getGlowColor());
    }
 
    return false;
}
 
bool GlowPrimitive2D::prepareValuesAndcheckValidity(
    basegfx::B2DRange& rGlowRange, basegfx::B2DRange& rClippedRange,
    basegfx::B2DVector& rDiscreteGlowSize, double& rfDiscreteGlowRadius,
    const geometry::ViewInformation2D& rViewInformation) const
{
    // no GlowRadius defined, done
    if (getGlowRadius() <= 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
    rGlowRange = getChildren().getB2DRange(rViewInformation);
 
    // no range of geometry, done
    if (rGlowRange.isEmpty())
        return false;
 
    // extend range by GlowRadius in all directions
    rGlowRange.grow(getGlowRadius());
 
    // initialize ClippedRange to full GlowRange -> all is visible
    rClippedRange = rGlowRange;
 
    // 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 GlowRadius to ensure needed parts are included
        basegfx::B2DRange aVisibleArea(rViewInformation.getViewport());
        aVisibleArea.grow(getGlowRadius());
 
        // 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 GlowRange 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 GlowRange. If it's too small to visualize, we are done
    rDiscreteGlowSize = rViewInformation.getObjectToViewTransformation() * rGlowRange.getRange();
    if (ceil(rDiscreteGlowSize.getX()) < 2.0 || ceil(rDiscreteGlowSize.getY()) < 2.0)
        return false;
 
    // calculate discrete pixel size of GlowRadius. If it's too small to visualize, we are done
    rfDiscreteGlowRadius = ceil(
        (rViewInformation.getObjectToViewTransformation() * basegfx::B2DVector(getGlowRadius(), 0))
            .getLength());
    if (rfDiscreteGlowRadius < 1.0)
        return false;
 
    return true;
}
 
void GlowPrimitive2D::create2DDecomposition(
    Primitive2DContainer& rContainer, const geometry::ViewInformation2D& rViewInformation) const
{
    basegfx::B2DRange aGlowRange;
    basegfx::B2DRange aClippedRange;
    basegfx::B2DVector aDiscreteGlowSize;
    double fDiscreteGlowRadius(0.0);
 
    // Check various validity details and calculate/prepare values. If false, we are done
    if (!prepareValuesAndcheckValidity(aGlowRange, aClippedRange, aDiscreteGlowSize,
                                       fDiscreteGlowRadius, 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 GlowRange
    const sal_uInt32 nDiscreteGlowWidth(ceil(aDiscreteGlowSize.getX()));
    const sal_uInt32 nDiscreteGlowHeight(ceil(aDiscreteGlowSize.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 GlowRange
    aEmbedding.scale(nDiscreteGlowWidth / aGlowRange.getWidth(),
                     nDiscreteGlowHeight / aGlowRange.getHeight());
 
    // Embed content graphics to TransformPrimitive2D
    const primitive2d::Primitive2DReference xEmbedRef(
        new primitive2d::TransformPrimitive2D(aEmbedding, Primitive2DContainer(getChildren())));
    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 glow 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 (!aAlpha.IsEmpty())
    {
        const Size& rBitmapExSizePixel(aAlpha.GetSizePixel());
 
        if (rBitmapExSizePixel.Width() > 0 && rBitmapExSizePixel.Height() > 0)
        {
            // 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>(rBitmapExSizePixel.Width()) != nDiscreteClippedWidth
                || static_cast<sal_uInt32>(rBitmapExSizePixel.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>(rBitmapExSizePixel.Width())
                                     / static_cast<double>(nDiscreteClippedWidth));
                const double fScaleY(static_cast<double>(rBitmapExSizePixel.Height())
                                     / static_cast<double>(nDiscreteClippedHeight));
 
                fScale = (fScaleX + fScaleY) * 0.5;
            }
 
            // fDiscreteGlowRadius is the size of the halo from each side of the object. The halo is the
            // border of glow color that fades from glow transparency level to fully transparent
            // When blurring a sharp boundary (our case), it gets 50% of original intensity, and
            // fades to both sides by the blur radius; thus blur radius is half of glow radius.
            // Consider glow transparency (initial transparency near the object edge)
            const AlphaMask mask(ProcessAndBlurAlphaMask(aAlpha, fDiscreteGlowRadius * fScale / 2.0,
                                                         fDiscreteGlowRadius * fScale / 2.0,
                                                         255 - getGlowColor().GetAlpha()));
 
            // The end result is the bitmap filled with glow color and blurred 8-bit alpha mask
            Bitmap bmp(aAlpha.GetSizePixel(), vcl::PixelFormat::N24_BPP);
            bmp.Erase(getGlowColor());
            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_glow.png",
                                      StreamMode::WRITE | StreamMode::TRUNC);
                    vcl::PngImageWriter aPNGWriter(aNew);
                    aPNGWriter.write(result);
                }
            }
#endif
 
            // Independent from discrete sizes of glow alpha creation, always
            // map and project glow result to geometry range extended by glow
            // 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 };
        }
    }
}
 
// Using tooling class BufferedDecompositionGroupPrimitive2D now, so
// no more need to locally do the buffered get2DDecomposition here,
// see BufferedDecompositionGroupPrimitive2D::get2DDecomposition
void GlowPrimitive2D::get2DDecomposition(Primitive2DDecompositionVisitor& rVisitor,
                                         const geometry::ViewInformation2D& rViewInformation) const
{
    basegfx::B2DRange aGlowRange;
    basegfx::B2DRange aClippedRange;
    basegfx::B2DVector aDiscreteGlowSize;
    double fDiscreteGlowRadius(0.0);
 
    // Check various validity details and calculate/prepare values. If false, we are done
    if (!prepareValuesAndcheckValidity(aGlowRange, aClippedRange, aDiscreteGlowSize,
                                       fDiscreteGlowRadius, rViewInformation))
        return;
 
    if (!getBuffered2DDecomposition().empty())
    {
        // First check is to detect if the last created decompose is capable
        // to represent the now requested visualization.
        // ClippedRange is the needed visualizationArea for the current glow
        // effect, LastClippedRange is the one from the existing/last rendering.
        // Check if last created area is sufficient and can be re-used
        if (!maLastClippedRange.isEmpty() && !maLastClippedRange.isInside(aClippedRange))
        {
            // To avoid unnecessary invalidations due to being *very* correct
            // with HairLines (which are view-dependent and thus change the
            // result(s) here slightly when changing zoom), add a slight unsharp
            // component if we have a ViewTransform. The derivation is inside
            // the range of half a pixel (due to one pixel hairline)
            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<GlowPrimitive2D*>(this)->setBuffered2DDecomposition(
                    Primitive2DContainer());
            }
        }
    }
 
    if (!getBuffered2DDecomposition().empty())
    {
        // Second check is to react on changes of the DiscreteGlowRadius when
        // zooming in/out.
        // Use the known last and current DiscreteGlowRadius to decide
        // if the visualization can be re-used. Be a little 'creative' here
        // and make it dependent on a *relative* change - it is not necessary
        // to re-create everytime if the exact value is missed since zooming
        // pixel-based glow effect is pretty good due to it's smooth nature
        bool bFree(mfLastDiscreteGlowRadius <= 0.0 || fDiscreteGlowRadius <= 0.0);
 
        if (!bFree)
        {
            const double fDiff(fabs(mfLastDiscreteGlowRadius - fDiscreteGlowRadius));
            const double fLen(fabs(mfLastDiscreteGlowRadius) + fabs(fDiscreteGlowRadius));
            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<GlowPrimitive2D*>(this)->setBuffered2DDecomposition(Primitive2DContainer());
        }
    }
 
    if (getBuffered2DDecomposition().empty())
    {
        // refresh last used DiscreteGlowRadius and ClippedRange to new remembered values
        const_cast<GlowPrimitive2D*>(this)->mfLastDiscreteGlowRadius = fDiscreteGlowRadius;
        const_cast<GlowPrimitive2D*>(this)->maLastClippedRange = aClippedRange;
    }
 
    // call parent, that will check for empty, call create2DDecomposition and
    // set as decomposition
    BufferedDecompositionGroupPrimitive2D::get2DDecomposition(rVisitor, rViewInformation);
}
 
basegfx::B2DRange
GlowPrimitive2D::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));
 
    // We need additional space for the glow from all sides
    aRetval.grow(getGlowRadius());
 
    return aRetval;
}
 
// provide unique ID
sal_uInt32 GlowPrimitive2D::getPrimitive2DID() const { return PRIMITIVE2D_ID_GLOWPRIMITIVE2D; }
 
} // end of namespace
 
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