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#include "qquickmaskextruder_p.h"
#include <QImage>
#include <QDebug>
QT_BEGIN_NAMESPACE
/*!
    \qmlclass MaskShape QQuickMaskExtruder
    \inqmlmodule QtQuick.Particles 2
    \inherits Shape
    \brief The MaskShape element allows you to represent an image as a shape to affectors and emitters.

*/
/*!
    \qmlproperty url QtQuick.Particles2::MaskShape::source

    The image to use as the mask. Areas with non-zero opacity
    will be considered inside the shape.
*/


QQuickMaskExtruder::QQuickMaskExtruder(QObject *parent) :
    QQuickParticleExtruder(parent)
  , m_lastWidth(-1)
  , m_lastHeight(-1)
{
}

QPointF QQuickMaskExtruder::extrude(const QRectF &r)
{
    ensureInitialized(r);
    if (!m_mask.count() || m_img.isNull())
        return r.topLeft();
    const QPointF p = m_mask[rand() % m_mask.count()];
    //### Should random sub-pixel positioning be added?
    return p + r.topLeft();
}

bool QQuickMaskExtruder::contains(const QRectF &bounds, const QPointF &point)
{
    ensureInitialized(bounds);//###Current usage patterns WILL lead to different bounds/r calls. Separate list?
    if (m_img.isNull())
        return false;
    QPoint p = point.toPoint() - bounds.topLeft().toPoint();
    return m_img.rect().contains(p) && (bool)m_img.pixelIndex(p);
}

void QQuickMaskExtruder::ensureInitialized(const QRectF &r)
{
    if (m_lastWidth == r.width() && m_lastHeight == r.height())
        return;//Same as before
    m_lastWidth = r.width();
    m_lastHeight = r.height();

    m_img = QImage();
    m_mask.clear();
    if (m_source.isEmpty())
        return;
    m_img = QImage(m_source.toLocalFile());
    if (m_img.isNull()){
        qWarning() << "MaskShape: Cannot load" << qPrintable(m_source.toLocalFile());
        return;
    }
    m_img = m_img.createAlphaMask();
    m_img = m_img.convertToFormat(QImage::Format_Mono);//Else LSB, but I think that's easier
    m_img = m_img.scaled(r.size().toSize());//TODO: Do they need aspect ratio stuff? Or tiling?
    for (int i=0; i<r.width(); i++){
        for (int j=0; j<r.height(); j++){
            if (m_img.pixelIndex(i,j))//Direct bit manipulation is presumably more efficient
                m_mask << QPointF(i,j);
        }
    }
}
QT_END_NAMESPACE