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#include "qoutlinemapper_p.h"

#include "qbezier_p.h"

#include "qmath.h"

#include "qpainterpath_p.h"

#include "qscopedvaluerollback.h"

#include <stdlib.h>

QT_BEGIN_NAMESPACE

#define qreal_to_fixed_26_6(f) (qRound(f * 64))

static const QRectF boundingRect(const QPointF *points, int pointCount)

{

    const QPointF *e = points;

    const QPointF *last = points + pointCount;

    qreal minx, maxx, miny, maxy;

    minx = maxx = e->x();

    miny = maxy = e->y();

    while (++e < last) {

        if (e->x() < minx)

            minx = e->x();

        else if (e->x() > maxx)

            maxx = e->x();

        if (e->y() < miny)

            miny = e->y();

        else if (e->y() > maxy)

            maxy = e->y();

    }

    return QRectF(QPointF(minx, miny), QPointF(maxx, maxy));

}

void QOutlineMapper::curveTo(const QPointF &cp1, const QPointF &cp2, const QPointF &ep) {

#ifdef QT_DEBUG_CONVERT

    printf("QOutlineMapper::curveTo() (%f, %f)\n", ep.x(), ep.y());

#endif

    if (!m_elements.size())

        return;

    QBezier bezier = QBezier::fromPoints(m_elements.last(), cp1, cp2, ep);

    bool outsideClip = false;

    // Test one point first before doing a full intersection test.

    if (!QRectF(m_clip_rect).contains(m_transform.map(ep))) {

        QRectF potentialCurveArea = m_transform.mapRect(bezier.bounds());

        outsideClip = !potentialCurveArea.intersects(m_clip_rect);

    }

    if (outsideClip) {

        // The curve is entirely outside the clip rect, so just

        // approximate it with a line that closes the path.

        lineTo(ep);

    } else {

        bezier.addToPolygon(m_elements, m_curve_threshold);

        m_element_types.reserve(m_elements.size());

        for (int i = m_elements.size() - m_element_types.size(); i; --i)

            m_element_types << QPainterPath::LineToElement;

    }

    Q_ASSERT(m_elements.size() == m_element_types.size());

}

QT_FT_Outline *QOutlineMapper::convertPath(const QPainterPath &path)

{

    Q_ASSERT(!path.isEmpty());

    int elmCount = path.elementCount();

#ifdef QT_DEBUG_CONVERT

    printf("QOutlineMapper::convertPath(), size=%d\n", elmCount);

#endif

    beginOutline(path.fillRule());

    for (int index=0; index<elmCount; ++index) {

        const QPainterPath::Element &elm = path.elementAt(index);

        switch (elm.type) {

        case QPainterPath::MoveToElement:

            if (index == elmCount - 1)

                continue;

            moveTo(elm);

            break;

        case QPainterPath::LineToElement:

            lineTo(elm);

            break;

        case QPainterPath::CurveToElement:

            curveTo(elm, path.elementAt(index + 1), path.elementAt(index + 2));

            index += 2;

            break;

        default:

            break; // This will never hit..

        }

    }

    endOutline();

    return outline();

}

QT_FT_Outline *QOutlineMapper::convertPath(const QVectorPath &path)

{

    int count = path.elementCount();

#ifdef QT_DEBUG_CONVERT

    printf("QOutlineMapper::convertPath(VP), size=%d\n", count);

#endif

    beginOutline(path.hasWindingFill() ? Qt::WindingFill : Qt::OddEvenFill);

    if (path.elements()) {

        // TODO: if we do closing of subpaths in convertElements instead we

        // could avoid this loop

        const QPainterPath::ElementType *elements = path.elements();

        const QPointF *points = reinterpret_cast<const QPointF *>(path.points());

        for (int index = 0; index < count; ++index) {

            switch (elements[index]) {

                case QPainterPath::MoveToElement:

                    if (index == count - 1)

                        continue;

                    moveTo(points[index]);

                    break;

                case QPainterPath::LineToElement:

                    lineTo(points[index]);

                    break;

                case QPainterPath::CurveToElement:

                    curveTo(points[index], points[index+1], points[index+2]);

                    index += 2;

                    break;

                default:

                    break; // This will never hit..

            }

        }

    } else {

        // ### We can kill this copying and just use the buffer straight...

        m_elements.resize(count);

        if (count)

            memcpy(static_cast<void *>(m_elements.data()), static_cast<const void *>(path.points()), count* sizeof(QPointF));

        m_element_types.resize(0);

    }

    endOutline();

    return outline();

}

void QOutlineMapper::endOutline()

{

    closeSubpath();

    if (m_elements.isEmpty()) {

        memset(&m_outline, 0, sizeof(m_outline));

        return;

    }

    QPointF *elements = m_elements.data();

    // Transform the outline

    if (m_transform.isIdentity()) {

        // Nothing to do

    } else if (m_transform.type() < QTransform::TxProject) {

        for (int i = 0; i < m_elements.size(); ++i)

            elements[i] = m_transform.map(elements[i]);

    } else {

        const QVectorPath vp((qreal *)elements, m_elements.size(),

                             m_element_types.size() ? m_element_types.data() : nullptr);

        QPainterPath path = vp.convertToPainterPath();

        path = m_transform.map(path);

        if (!(m_outline.flags & QT_FT_OUTLINE_EVEN_ODD_FILL))

            path.setFillRule(Qt::WindingFill);

        if (path.isEmpty()) {

            m_valid = false;

        } else {

            QTransform oldTransform = m_transform;

            m_transform.reset();

            convertPath(path);

            m_transform = oldTransform;

        }

        return;

    }

    controlPointRect = boundingRect(elements, m_elements.size());

#ifdef QT_DEBUG_CONVERT

    printf(" - control point rect (%.2f, %.2f) %.2f x %.2f, clip=(%d,%d, %dx%d)\n",

           controlPointRect.x(), controlPointRect.y(),

           controlPointRect.width(), controlPointRect.height(),

           m_clip_rect.x(), m_clip_rect.y(), m_clip_rect.width(), m_clip_rect.height());

#endif

    // Check for out of dev bounds...

    const bool do_clip = !m_in_clip_elements && ((controlPointRect.left() < -QT_RASTER_COORD_LIMIT

                          || controlPointRect.right() > QT_RASTER_COORD_LIMIT

                          || controlPointRect.top() < -QT_RASTER_COORD_LIMIT

                          || controlPointRect.bottom() > QT_RASTER_COORD_LIMIT

                          || controlPointRect.width() > QT_RASTER_COORD_LIMIT

                          || controlPointRect.height() > QT_RASTER_COORD_LIMIT));

    if (do_clip) {

        clipElements(elements, elementTypes(), m_elements.size());

    } else {

        convertElements(elements, elementTypes(), m_elements.size());

    }

}

void QOutlineMapper::convertElements(const QPointF *elements,

                                       const QPainterPath::ElementType *types,

                                       int element_count)

{

    if (types) {

        // Translate into FT coords

        const QPointF *e = elements;

        for (int i=0; i<element_count; ++i) {

            switch (*types) {

            case QPainterPath::MoveToElement:

                {

                    QT_FT_Vector pt_fixed = { qreal_to_fixed_26_6(e->x()),

                                              qreal_to_fixed_26_6(e->y()) };

                    if (i != 0)

                        m_contours << m_points.size() - 1;

                    m_points << pt_fixed;

                    m_tags <<  QT_FT_CURVE_TAG_ON;

                }

                break;

            case QPainterPath::LineToElement:

                {

                    QT_FT_Vector pt_fixed = { qreal_to_fixed_26_6(e->x()),

                                              qreal_to_fixed_26_6(e->y()) };

                    m_points << pt_fixed;

                    m_tags << QT_FT_CURVE_TAG_ON;

                }

                break;

            case QPainterPath::CurveToElement:

                {

                    QT_FT_Vector cp1_fixed = { qreal_to_fixed_26_6(e->x()),

                                               qreal_to_fixed_26_6(e->y()) };

                    ++e;

                    QT_FT_Vector cp2_fixed = { qreal_to_fixed_26_6((e)->x()),

                                               qreal_to_fixed_26_6((e)->y()) };

                    ++e;

                    QT_FT_Vector ep_fixed = { qreal_to_fixed_26_6((e)->x()),

                                              qreal_to_fixed_26_6((e)->y()) };

                    m_points << cp1_fixed << cp2_fixed << ep_fixed;

                    m_tags << QT_FT_CURVE_TAG_CUBIC

                           << QT_FT_CURVE_TAG_CUBIC

                           << QT_FT_CURVE_TAG_ON;

                    types += 2;

                    i += 2;

                }

                break;

            default:

                break;

            }

            ++types;

            ++e;

        }

    } else {

        // Plain polygon...

        const QPointF *last = elements + element_count;

        const QPointF *e = elements;

        while (e < last) {

            QT_FT_Vector pt_fixed = { qreal_to_fixed_26_6(e->x()),

                                      qreal_to_fixed_26_6(e->y()) };

            m_points << pt_fixed;

            m_tags << QT_FT_CURVE_TAG_ON;

            ++e;

        }

    }

    // close the very last subpath

    m_contours << m_points.size() - 1;

    m_outline.n_contours = m_contours.size();

    m_outline.n_points = m_points.size();

    m_outline.points = m_points.data();

    m_outline.tags = m_tags.data();

    m_outline.contours = m_contours.data();

#ifdef QT_DEBUG_CONVERT

    printf("QOutlineMapper::endOutline\n");

    printf(" - contours: %d\n", m_outline.n_contours);

    for (int i=0; i<m_outline.n_contours; ++i) {

        printf("   - %d\n", m_outline.contours[i]);

    }

    printf(" - points: %d\n", m_outline.n_points);

    for (int i=0; i<m_outline.n_points; ++i) {

        printf("   - %d -- %.2f, %.2f, (%d, %d)\n", i,

               (double) (m_outline.points[i].x / 64.0),

               (double) (m_outline.points[i].y / 64.0),

               (int) m_outline.points[i].x, (int) m_outline.points[i].y);

    }

#endif

}

void QOutlineMapper::clipElements(const QPointF *elements,

                                    const QPainterPath::ElementType *types,

                                    int element_count)

{

    // We could save a bit of time by actually implementing them fully

    // instead of going through convenience functionallity, but since

    // this part of code hardly every used, it shouldn't matter.

    QScopedValueRollback<bool> in_clip_elements(m_in_clip_elements, true);

    QPainterPath path;

    if (!(m_outline.flags & QT_FT_OUTLINE_EVEN_ODD_FILL))

        path.setFillRule(Qt::WindingFill);

    if (types) {

        for (int i=0; i<element_count; ++i) {

            switch (types[i]) {

            case QPainterPath::MoveToElement:

                path.moveTo(elements[i]);

                break;

            case QPainterPath::LineToElement:

                path.lineTo(elements[i]);

                break;

            case QPainterPath::CurveToElement:

                path.cubicTo(elements[i], elements[i+1], elements[i+2]);

                i += 2;

                break;

            default:

                break;

            }

        }

    } else {

        path.moveTo(elements[0]);

        for (int i=1; i<element_count; ++i)

            path.lineTo(elements[i]);

    }

    QPainterPath clipPath;

    clipPath.addRect(m_clip_rect);

    QPainterPath clippedPath = path.intersected(clipPath);

    if (clippedPath.isEmpty()) {

        m_valid = false;

    } else {

        QTransform oldTransform = m_transform;

        m_transform.reset();

        convertPath(clippedPath);

        m_transform = oldTransform;

    }

}

QT_END_NAMESPACE