/****************************************************************************

**

** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the QtOpenGL module of the Qt Toolkit.

**

**

**

** $QT_END_LICENSE$

**

****************************************************************************/

#include "starwidget.h"

StarWidget::StarWidget(QWidget *parent)

    : QWidget(parent)

    , path(VG_INVALID_HANDLE)

    , pen(Qt::red, 4.0, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin)

    , brush(Qt::yellow)

{

    setMinimumSize(220, 250);

    setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);

}

static VGubyte const starSegments[] = {

    VG_MOVE_TO_ABS,

    VG_LINE_TO_REL,

    VG_LINE_TO_REL,

    VG_LINE_TO_REL,

    VG_LINE_TO_REL,

    VG_CLOSE_PATH

};

static VGfloat const starCoords[] = {

    110, 35,

    50, 160,

    -130, -100,

    160, 0,

    -130, 100

};

void StarWidget::paintEvent(QPaintEvent *)

{

    QPainter painter;

    painter.begin(this);

    // Make sure that we are using the OpenVG paint engine.

    if (painter.paintEngine()->type() != QPaintEngine::OpenVG) {

#ifdef Q_WS_QWS

        qWarning("Not using OpenVG: use the '-display' option to specify an OpenVG driver");

#else

        qWarning("Not using OpenVG: specify '-graphicssystem OpenVG'");

#endif

        return;

    }

    // Select a pen and a brush for drawing the star.

    painter.setPen(pen);

    painter.setBrush(brush);

    // We want the star border to be anti-aliased.

    painter.setRenderHints(QPainter::Antialiasing);

    // Flush the state changes to the OpenVG implementation

    // and prepare to perform raw OpenVG calls.

    painter.beginNativePainting();

    // Cache the path if we haven't already or if the path has

    // become invalid because the window's context has changed.

    if (path == VG_INVALID_HANDLE || !vgGetPathCapabilities(path)) {

        path = vgCreatePath(VG_PATH_FORMAT_STANDARD,

                            VG_PATH_DATATYPE_F,

                            1.0f, // scale

                            0.0f, // bias

                            6,    // segmentCapacityHint

                            10,   // coordCapacityHint

                            VG_PATH_CAPABILITY_ALL);

        vgAppendPathData(path, sizeof(starSegments), starSegments, starCoords);

    }

    // Draw the star directly using the OpenVG API.

    vgDrawPath(path, VG_FILL_PATH | VG_STROKE_PATH);

    // Restore normal QPainter operations.

    painter.endNativePainting();

    painter.end();

}