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#include "qsgdistancefieldglyphnode_p.h"
#include "qsgdistancefieldglyphnode_p_p.h"
#include "qsgdistancefieldglyphcache_p.h"
#include <private/qsgcontext_p.h>

QT_BEGIN_NAMESPACE

QSGDistanceFieldGlyphNode::QSGDistanceFieldGlyphNode()
    : m_material(0)
    , m_glyph_cache(0)
    , m_geometry(QSGGeometry::defaultAttributes_TexturedPoint2D(), 0)
    , m_style(QSGText::Normal)
    , m_antialiasingMode(GrayAntialiasing)
{
    m_geometry.setDrawingMode(GL_TRIANGLES);
    setGeometry(&m_geometry);

#ifndef QT_OPENGL_ES
    setPreferredAntialiasingMode(QSGGlyphNode::SubPixelAntialiasing);
#endif
}

QSGDistanceFieldGlyphNode::~QSGDistanceFieldGlyphNode()
{
    delete m_material;
    if (m_glyph_cache) {
        const QVector<quint32> &glyphIndexes = m_glyphs.glyphIndexes();
        m_glyph_cache->derefGlyphs(glyphIndexes.count(), glyphIndexes.constData());
    }
}

void QSGDistanceFieldGlyphNode::setColor(const QColor &color)
{
    m_color = color;
    if (m_material != 0) {
        m_material->setColor(color);
        setMaterial(m_material); // Indicate the material state has changed
    }
}

void QSGDistanceFieldGlyphNode::setPreferredAntialiasingMode(AntialiasingMode mode)
{
    if (mode == m_antialiasingMode)
        return;
    m_antialiasingMode = mode;
    updateMaterial();
}

void QSGDistanceFieldGlyphNode::setGlyphs(const QPointF &position, const QGlyphRun &glyphs)
{
    QRawFont font = glyphs.rawFont();
    m_position = QPointF(position.x(), position.y() - font.ascent());
    m_glyphs = glyphs;

    updateFont();
    updateGeometry();
    updateMaterial();

#ifdef QML_RUNTIME_TESTING
    description = QLatin1String("glyphs");
#endif
}

void QSGDistanceFieldGlyphNode::setStyle(QSGText::TextStyle style)
{
    m_style = style;
}

void QSGDistanceFieldGlyphNode::setStyleColor(const QColor &color)
{
    m_styleColor = color;
}

void QSGDistanceFieldGlyphNode::updateGeometry()
{
    Q_ASSERT(m_glyph_cache);

    QSGGeometry *g = geometry();
    QRectF boundingRect;

    const QVector<quint32> &glyphIndexes = m_glyphs.glyphIndexes();

    m_glyph_cache->populate(glyphIndexes.count(), glyphIndexes.constData());

    Q_ASSERT(g->indexType() == GL_UNSIGNED_SHORT);
    g->allocate(glyphIndexes.size() * 4, glyphIndexes.size() * 6);
    QVector4D *vp = (QVector4D *)g->vertexData();
    ushort *ip = g->indexDataAsUShort();

    QPointF margins(2, 2);
    QPointF texMargins = margins / m_glyph_cache->fontScale();

    for (int i = 0; i < glyphIndexes.size(); ++i) {
        quint32 glyphIndex = glyphIndexes.at(i);
        QSGDistanceFieldGlyphCache::Metrics metrics = m_glyph_cache->glyphMetrics(glyphIndex);
        QSGDistanceFieldGlyphCache::TexCoord c = m_glyph_cache->glyphTexCoord(glyphIndex);

        if (!metrics.isNull() && !c.isNull()) {
                metrics.width += margins.x() * 2;
                metrics.height += margins.y() * 2;
                metrics.baselineX -= margins.x();
                metrics.baselineY += margins.y();
                c.xMargin -= texMargins.x();
                c.yMargin -= texMargins.y();
                c.width += texMargins.x() * 2;
                c.height += texMargins.y() * 2;
        }

        QPointF glyphPosition = m_glyphs.positions().at(i) + m_position;
        qreal x = glyphPosition.x() + metrics.baselineX;
        qreal y = glyphPosition.y() - metrics.baselineY;

        boundingRect |= QRectF(x, y, metrics.width, metrics.height);

        float cx1 = x;
        float cx2 = x + metrics.width;
        float cy1 = y;
        float cy2 = y + metrics.height;

        float tx1 = c.x + c.xMargin;
        float tx2 = tx1 + c.width;
        float ty1 = c.y + c.yMargin;
        float ty2 = ty1 + c.height;

        if (m_baseLine.isNull())
            m_baseLine = glyphPosition;

        int vi = i & 1 ? (glyphIndexes.size() + 1) / 2 + i / 2 : i / 2;
        vp[4 * vi + 0] = QVector4D(cx1, cy1, tx1, ty1);
        vp[4 * vi + 1] = QVector4D(cx2, cy1, tx2, ty1);
        vp[4 * vi + 2] = QVector4D(cx1, cy2, tx1, ty2);
        vp[4 * vi + 3] = QVector4D(cx2, cy2, tx2, ty2);

        int o = i * 4;
        ip[6 * i + 0] = o + 0;
        ip[6 * i + 1] = o + 2;
        ip[6 * i + 2] = o + 3;
        ip[6 * i + 3] = o + 3;
        ip[6 * i + 4] = o + 1;
        ip[6 * i + 5] = o + 0;
    }

    setBoundingRect(boundingRect);
    markDirty(DirtyGeometry);
}

void QSGDistanceFieldGlyphNode::updateFont()
{
    m_glyph_cache = QSGDistanceFieldGlyphCache::get(QGLContext::currentContext(), m_glyphs.rawFont());
}

void QSGDistanceFieldGlyphNode::updateMaterial()
{
    delete m_material;

    if (m_style == QSGText::Normal) {
        if (m_antialiasingMode == SubPixelAntialiasing)
            m_material = new QSGSubPixelDistanceFieldTextMaterial;
        else
            m_material = new QSGDistanceFieldTextMaterial;
    } else {
        QSGDistanceFieldStyledTextMaterial *material;
        if (m_style == QSGText::Outline) {
            material = new QSGDistanceFieldOutlineTextMaterial;
        } else {
            QSGDistanceFieldShiftedStyleTextMaterial *sMaterial = new QSGDistanceFieldShiftedStyleTextMaterial;
            if (m_style == QSGText::Raised)
                sMaterial->setShift(QPointF(0.0, 1.0));
            else
                sMaterial->setShift(QPointF(0.0, -1.0));
            material = sMaterial;
        }
        material->setStyleColor(m_styleColor);
        m_material = material;
    }

    m_material->setGlyphCache(m_glyph_cache);
    m_material->setColor(m_color);
    setMaterial(m_material);
}

QT_END_NAMESPACE