source: trunk/src/gui/painting/qpaintengine_alpha.cpp@ 778

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** Contact: Nokia Corporation ([email protected])
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#include <qglobal.h>

#ifndef QT_NO_PRINTER
#include <qdebug.h>
#include "private/qpaintengine_alpha_p.h"

#include "private/qpicture_p.h"
#include "QtGui/qpicture.h"

QT_BEGIN_NAMESPACE

QAlphaPaintEngine::QAlphaPaintEngine(QAlphaPaintEnginePrivate &data, PaintEngineFeatures devcaps)
    : QPaintEngine(data, devcaps)
{

}

QAlphaPaintEngine::~QAlphaPaintEngine()
{

}

bool QAlphaPaintEngine::begin(QPaintDevice *pdev)
{
    Q_D(QAlphaPaintEngine);

    d->m_continueCall = true;
    if (d->m_pass != 0) {
        return true;
    }

    d->m_savedcaps = gccaps;
    d->m_pdev = pdev;

    d->m_alphaPen = false;
    d->m_alphaBrush = false;
    d->m_alphaOpacity = false;
    d->m_hasalpha = false;
    d->m_advancedPen = false;
    d->m_advancedBrush = false;
    d->m_complexTransform = false;
    d->m_emulateProjectiveTransforms = false;

    // clear alpha region
    d->m_alphargn = QRegion();
    d->m_cliprgn = QRegion();
    d->m_pen = QPen();
    d->m_transform = QTransform();

    flushAndInit();

    return true;
}

Q_GUI_EXPORT extern int qt_defaultDpiX();
Q_GUI_EXPORT extern int qt_defaultDpiY();

bool QAlphaPaintEngine::end()
{
    Q_D(QAlphaPaintEngine);

    d->m_continueCall = true;
    if (d->m_pass != 0) {
        return true;
    }

    flushAndInit(false);
    return true;
}

void QAlphaPaintEngine::updateState(const QPaintEngineState &state)
{
    Q_D(QAlphaPaintEngine);

    DirtyFlags flags = state.state();
    if (flags & QPaintEngine::DirtyTransform) {
        d->m_transform = state.transform();
        d->m_complexTransform = (d->m_transform.type() > QTransform::TxScale);
        d->m_emulateProjectiveTransforms = !(d->m_savedcaps & QPaintEngine::PerspectiveTransform)
                                           && !(d->m_savedcaps & QPaintEngine::AlphaBlend)
                                           && (d->m_transform.type() >= QTransform::TxProject);
    }
    if (flags & QPaintEngine::DirtyPen) {
        d->m_pen = state.pen();
        if (d->m_pen.style() == Qt::NoPen) {
            d->m_advancedPen = false;
            d->m_alphaPen = false;
        } else {
            d->m_advancedPen = (d->m_pen.brush().style() != Qt::SolidPattern);
            d->m_alphaPen = !d->m_pen.brush().isOpaque();
        }
    }

    if (d->m_pass != 0) {
        d->m_continueCall = true;
        return;
    }
    d->m_continueCall = false;

    if (flags & QPaintEngine::DirtyOpacity) {
        d->m_alphaOpacity = (state.opacity() != 1.0f);
    }

    if (flags & QPaintEngine::DirtyBrush) {
        if (state.brush().style() == Qt::NoBrush) {
            d->m_advancedBrush = false;
            d->m_alphaBrush = false;
        } else {
            d->m_advancedBrush = (state.brush().style() != Qt::SolidPattern);
            d->m_alphaBrush = !state.brush().isOpaque();
        }
    }


    d->m_hasalpha = d->m_alphaOpacity || d->m_alphaBrush || d->m_alphaPen;

    if (d->m_picengine)
        d->m_picengine->updateState(state);
}

void QAlphaPaintEngine::drawPath(const QPainterPath &path)
{
    Q_D(QAlphaPaintEngine);

    QRectF tr = d->addPenWidth(path);

    if (d->m_pass == 0) {
        d->m_continueCall = false;
        if (d->m_hasalpha || d->m_advancedPen || d->m_advancedBrush
            || d->m_emulateProjectiveTransforms)
        {
            d->addAlphaRect(tr);
        }
        if (d->m_picengine)
            d->m_picengine->drawPath(path);
    } else {
        d->m_continueCall = !d->fullyContained(tr);
    }
}

void QAlphaPaintEngine::drawPolygon(const QPointF *points, int pointCount, PolygonDrawMode mode)
{
    Q_D(QAlphaPaintEngine);

    QPolygonF poly;
    for (int i=0; i<pointCount; ++i)
        poly.append(points[i]);

    QPainterPath path;
    path.addPolygon(poly);
    QRectF tr = d->addPenWidth(path);

    if (d->m_pass == 0) {
        d->m_continueCall = false;
        if (d->m_hasalpha || d->m_advancedPen || d->m_advancedBrush
            || d->m_emulateProjectiveTransforms)
        {
            d->addAlphaRect(tr);
        }

        if (d->m_picengine)
            d->m_picengine->drawPolygon(points, pointCount, mode);
    } else {
        d->m_continueCall = !d->fullyContained(tr);
    }
}

void QAlphaPaintEngine::drawPixmap(const QRectF &r, const QPixmap &pm, const QRectF &sr)
{
    Q_D(QAlphaPaintEngine);

    QRectF tr = d->m_transform.mapRect(r);
    if (d->m_pass == 0) {
        d->m_continueCall = false;
        if (pm.hasAlpha() || d->m_alphaOpacity || d->m_complexTransform || pm.isQBitmap()) {
            d->addAlphaRect(tr);
        }

        if (d->m_picengine)
            d->m_picengine->drawPixmap(r, pm, sr);

    } else {
        d->m_continueCall = !d->fullyContained(tr);
    }
}

void QAlphaPaintEngine::drawImage(const QRectF &r, const QImage &image, const QRectF &sr)
{
    Q_D(QAlphaPaintEngine);

    QRectF tr = d->m_transform.mapRect(r);
    if (d->m_pass == 0) {
        d->m_continueCall = false;
        if (image.hasAlphaChannel() || d->m_alphaOpacity || d->m_complexTransform) {
            d->addAlphaRect(tr);
        }

        if (d->m_picengine)
            d->m_picengine->drawImage(r, image, sr);

    } else {
        d->m_continueCall = !d->fullyContained(tr);
    }
}

void QAlphaPaintEngine::drawTextItem(const QPointF &p, const QTextItem &textItem)
{
    Q_D(QAlphaPaintEngine);

    QRectF tr(p.x(), p.y() - textItem.ascent(), textItem.width() + 5, textItem.ascent() + textItem.descent() + 5);
    tr = d->m_transform.mapRect(tr);

    if (d->m_pass == 0) {
        d->m_continueCall = false;
        if (d->m_alphaPen || d->m_alphaOpacity || d->m_advancedPen) {
            d->addAlphaRect(tr);
        }
        if (d->m_picengine) {
            d->m_picengine->drawTextItem(p, textItem);
        }
    } else {
        d->m_continueCall = !d->fullyContained(tr);
    }
}

void QAlphaPaintEngine::drawTiledPixmap(const QRectF &r, const QPixmap &pixmap, const QPointF &s)
{
    Q_D(QAlphaPaintEngine);

    QRectF brect = d->m_transform.mapRect(r);

    if (d->m_pass == 0) {
        d->m_continueCall = false;
        if (pixmap.hasAlpha() || d->m_alphaOpacity || d->m_complexTransform || pixmap.isQBitmap()) {
            d->addAlphaRect(brect);
        }
        if (d->m_picengine)
            d->m_picengine->drawTiledPixmap(r, pixmap, s);
    } else {
        d->m_continueCall = !d->fullyContained(brect);
    }
}

QRegion QAlphaPaintEngine::alphaClipping() const
{
    Q_D(const QAlphaPaintEngine);
    return d->m_cliprgn;
}

bool QAlphaPaintEngine::continueCall() const
{
    Q_D(const QAlphaPaintEngine);
    return d->m_continueCall;
}

void QAlphaPaintEngine::flushAndInit(bool init)
{
    Q_D(QAlphaPaintEngine);
    Q_ASSERT(d->m_pass == 0);

    if (d->m_pic) {
        d->m_picpainter->end();

        // set clip region
        d->m_alphargn = d->m_alphargn.intersected(QRect(0, 0, d->m_pdev->width(), d->m_pdev->height()));

        // just use the bounding rect if it's a complex region..
        QVector<QRect> rects = d->m_alphargn.rects();
        if (rects.size() > 10) {
            QRect br = d->m_alphargn.boundingRect();
            d->m_alphargn = QRegion(br);
            rects.clear();
            rects.append(br);
        }