C++ CustomEffect类代码示例

void tst_QGraphicsEffect::itemHasNoContents()
{
    QGraphicsRectItem *parent = new QGraphicsRectItem;
    parent->setFlag(QGraphicsItem::ItemHasNoContents);

    MyGraphicsItem *child = new MyGraphicsItem;
    child->setParentItem(parent);
    child->resize(200, 200);

    QGraphicsScene scene;
    scene.addItem(parent);

    QGraphicsView view(&scene);
    view.show();
    QTest::qWaitForWindowShown(&view);
#ifdef Q_OS_MAC
    if (QSysInfo::MacintoshVersion == QSysInfo::MV_LION) {
        QEXPECT_FAIL("", "QTBUG-26858", Abort);
    }
#endif
    QTRY_COMPARE(child->nbPaint, 1);

    CustomEffect *effect = new CustomEffect;
    parent->setGraphicsEffect(effect);
    QTRY_COMPARE(effect->numRepaints, 1);

    for (int i = 0; i < 3; ++i) {
        effect->reset();
        effect->update();
        QTRY_COMPARE(effect->numRepaints, 1);
    }
}

void tst_QGraphicsEffect::itemHasNoContents()
{
    QGraphicsRectItem *parent = new QGraphicsRectItem;
    parent->setFlag(QGraphicsItem::ItemHasNoContents);

    MyGraphicsItem *child = new MyGraphicsItem;
    child->setParentItem(parent);
    child->resize(200, 200);

    QGraphicsScene scene;
    scene.addItem(parent);

    QGraphicsView view(&scene);
    view.show();
    QTest::qWaitForWindowShown(&view);
    QTRY_COMPARE(child->nbPaint, 1);

    CustomEffect *effect = new CustomEffect;
    parent->setGraphicsEffect(effect);
    QTRY_COMPARE(effect->numRepaints, 1);

    for (int i = 0; i < 3; ++i) {
        effect->reset();
        effect->update();
        QTRY_COMPARE(effect->numRepaints, 1);
    }
}

void tst_QGraphicsEffect::setEnabled()
{
    CustomEffect effect;
    QVERIFY(effect.isEnabled());

    effect.setEnabled(false);
    QVERIFY(!effect.isEnabled());
}

void tst_QGraphicsEffect::boundingRectFor()
{
    CustomEffect effect;
    int margin = effect.margin();
    const QRectF source(0, 0, 100, 100);
    QCOMPARE(effect.boundingRectFor(source), source.adjusted(-margin, -margin, margin, margin));

    effect.setMargin(margin = 20);
    QCOMPARE(effect.boundingRectFor(source), source.adjusted(-margin, -margin, margin, margin));
}

int
main (int argc, char **argv)
{
	cairo_t *cr;
	cairo_surface_t *dst, *src;
	CustomEffect *effect;
	PixelShader *shader;
	int stride = width * 4;
        Rect bounds = Rect (0, 0, width, height);
	gpointer data;
	bool status;

	if (argc < 2) {
		printf ("usage: %s SHADERFILE\n", argv[0]);
		return 1;
	}

	gtk_init (&argc, &argv);

	runtime_init_desktop ();

	data = g_malloc0 (height * stride);
        dst = cairo_image_surface_create_for_data ((unsigned char *) data,
                                                   CAIRO_FORMAT_ARGB32,
                                                   width, height, stride);
	src = cairo_surface_create_similar (dst,
					    CAIRO_CONTENT_COLOR_ALPHA,
					    width, height);
        cr = cairo_create (dst);

	effect = new CustomEffect ();
	shader = new PixelShader ();

	shader->SetTokensFromPath (argv[1]);
	effect->SetPixelShader (shader);

	status = effect->Render (cr, src, NULL, 0, 0, width, height);

	effect->unref ();
	shader->unref ();

        cairo_destroy (cr);
	cairo_surface_destroy (src);
	cairo_surface_destroy (dst);
	g_free (data);

	runtime_shutdown ();

	return status != true;
}

void tst_QGraphicsEffect::draw()
{
    QGraphicsScene scene;
    CustomItem *item = new CustomItem(0, 0, 100, 100);
    scene.addItem(item);

    QGraphicsView view(&scene);
    view.show();
    QTest::qWaitForWindowShown(&view);
    QTRY_VERIFY(item->numRepaints > 0);
    item->reset();

    // Make sure installing the effect triggers a repaint.
    CustomEffect *effect = new CustomEffect;
    item->setGraphicsEffect(effect);
    QTRY_COMPARE(effect->numRepaints, 1);
    QTRY_COMPARE(item->numRepaints, 1);

    // Make sure QPainter* and QStyleOptionGraphicsItem* stays persistent
    // during QGraphicsEffect::draw/QGraphicsItem::paint.
    QVERIFY(effect->m_painter);
    QCOMPARE(effect->m_painter, item->m_painter);
    QCOMPARE(effect->m_styleOption, item->m_styleOption);
    // Make sure QGraphicsEffect::source is persistent.
    QCOMPARE(effect->m_source, effect->source());
    effect->reset();
    item->reset();

    // Make sure updating the source triggers a repaint.
    item->update();
    QTRY_COMPARE(effect->numRepaints, 1);
    QTRY_COMPARE(item->numRepaints, 1);
    QVERIFY(effect->m_sourceChangedFlags & QGraphicsEffect::SourceInvalidated);
    effect->reset();
    item->reset();

    // Make sure changing the effect's bounding rect triggers a repaint.
    effect->setMargin(20);
    QTRY_COMPARE(effect->numRepaints, 1);
    QTRY_COMPARE(item->numRepaints, 1);
    effect->reset();
    item->reset();

    // Make sure change the item's bounding rect triggers a repaint.
    item->setRect(0, 0, 50, 50);
    QTRY_COMPARE(effect->numRepaints, 1);
    QTRY_COMPARE(item->numRepaints, 1);
    QVERIFY(effect->m_sourceChangedFlags & QGraphicsEffect::SourceBoundingRectChanged);
    effect->reset();
    item->reset();

    // Make sure the effect is the one to issue a repaint of the item.
    effect->doNothingInDraw = true;
    item->update();
    QTRY_COMPARE(effect->numRepaints, 1);
    QCOMPARE(item->numRepaints, 0);
    effect->doNothingInDraw = false;
    effect->reset();
    item->reset();

    // Make sure we update the source when disabling/enabling the effect.
    effect->setEnabled(false);
    QTest::qWait(50);
    QCOMPARE(effect->numRepaints, 0);
    QCOMPARE(item->numRepaints, 1);
    effect->reset();
    item->reset();

    effect->setEnabled(true);
    QTRY_COMPARE(effect->numRepaints, 1);
    QTRY_COMPARE(item->numRepaints, 1);
    effect->reset();
    item->reset();

    // Effect is already enabled; nothing should happen.
    effect->setEnabled(true);
    QTest::qWait(50);
    QCOMPARE(effect->numRepaints, 0);
    QCOMPARE(item->numRepaints, 0);

    // Make sure uninstalling an effect triggers a repaint.
    QPointer<CustomEffect> ptr = effect;
    item->setGraphicsEffect(0);
    QVERIFY(!ptr);
    QTRY_COMPARE(item->numRepaints, 1);
}

void tst_QGraphicsEffect::boundingRect2()
{
    CustomEffect *effect = new CustomEffect;
    QGraphicsRectItem *root = new QGraphicsRectItem;
    root->setGraphicsEffect(effect);

    QGraphicsRectItem *child = new QGraphicsRectItem;
    QRectF childRect(0, 0, 100, 100);
    child->setFlag(QGraphicsItem::ItemClipsChildrenToShape);
    child->setRect(childRect);
    child->setParentItem(root);

    QGraphicsRectItem *grandChild = new QGraphicsRectItem;
    QRectF grandChildRect(0, 0, 200, 200);
    grandChild->setRect(grandChildRect);
    grandChild->setParentItem(child);

    // Make sure the effect's bounding rect is clipped to the child's bounding rect.
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(childRect));

    // Disable ItemClipsChildrenToShape; effect's bounding rect is no longer clipped.
    child->setFlag(QGraphicsItem::ItemClipsChildrenToShape, false);
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(childRect | grandChildRect));

    // Add root item to a scene, do the same tests as above. Results should be the same.
    QGraphicsScene scene;
    scene.addItem(root);

    child->setFlag(QGraphicsItem::ItemClipsChildrenToShape);
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(childRect));

    child->setFlag(QGraphicsItem::ItemClipsChildrenToShape, false);
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(childRect | grandChildRect));

    // Now add the scene to a view, results should be the same.
    QGraphicsView view(&scene);

    child->setFlag(QGraphicsItem::ItemClipsChildrenToShape);
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(childRect));

    child->setFlag(QGraphicsItem::ItemClipsChildrenToShape, false);
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(childRect | grandChildRect));

    CustomEffect *childEffect = new CustomEffect;
    child->setGraphicsEffect(childEffect);
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(childEffect->boundingRectFor(childRect | grandChildRect)));

    child->setGraphicsEffect(0);
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(childRect | grandChildRect));
}

void tst_QGraphicsEffect::boundingRect()
{
    // No source; empty bounding rect.
    CustomEffect *effect = new CustomEffect;
    QCOMPARE(effect->boundingRect(), QRectF());

    // Install effect on QGraphicsItem.
    QRectF itemRect(0, 0, 100, 100);
    QGraphicsRectItem *item = new QGraphicsRectItem;
    item->setRect(itemRect);
    item->setGraphicsEffect(effect);
    int margin = effect->margin();
    QCOMPARE(effect->boundingRect(), itemRect.adjusted(-margin, -margin, margin, margin));
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(itemRect));

    // Make sure disabling/enabling the effect doesn't change the bounding rect.
    effect->setEnabled(false);
    QCOMPARE(effect->boundingRect(), itemRect.adjusted(-margin, -margin, margin, margin));
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(itemRect));
    effect->setEnabled(true);
    QCOMPARE(effect->boundingRect(), itemRect.adjusted(-margin, -margin, margin, margin));
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(itemRect));

    // Change effect margins.
    effect->setMargin(margin = 20);
    QCOMPARE(effect->boundingRect(), itemRect.adjusted(-margin, -margin, margin, margin));
    QCOMPARE(effect->boundingRect(), effect->boundingRectFor(itemRect));

    // Uninstall effect on QGraphicsItem.
    QPointer<CustomEffect> ptr = effect;
    item->setGraphicsEffect(0);
    QVERIFY(!ptr);

    delete item;
}