C++ QSGGeometryNode类代码示例

void QSGNode::insertChildNodeBefore(QSGNode *node, QSGNode *before)
{
    //Q_ASSERT_X(!m_children.contains(node), "QSGNode::insertChildNodeBefore", "QSGNode is already a child!");
    Q_ASSERT_X(!node->m_parent, "QSGNode::insertChildNodeBefore", "QSGNode already has a parent");
    Q_ASSERT_X(before && before->m_parent == this, "QSGNode::insertChildNodeBefore", "The parent of \'before\' is wrong");

#ifndef QT_NO_DEBUG
    if (node->type() == QSGNode::GeometryNodeType) {
        QSGGeometryNode *g = static_cast<QSGGeometryNode *>(node);
        Q_ASSERT_X(g->material(), "QSGNode::insertChildNodeBefore", "QSGGeometryNode is missing material");
        Q_ASSERT_X(g->geometry(), "QSGNode::insertChildNodeBefore", "QSGGeometryNode is missing geometry");
    }
#endif

    QSGNode *previous = before->m_previousSibling;
    if (previous)
        previous->m_nextSibling = node;
    else
        m_firstChild = node;
    node->m_previousSibling = previous;
    node->m_nextSibling = before;
    before->m_previousSibling = node;
    node->m_parent = this;

    node->markDirty(DirtyNodeAdded);
}

    QSGNode* TriangleElement::updatePaintNode(QSGNode* n, UpdatePaintNodeData*) {
        if (n == NULL) {
            n = new QSGNode;
        }

        QSGGeometryNode* geomnode = new QSGGeometryNode();

        QSGGeometry::Point2D* v = m_Geometry.vertexDataAsPoint2D();
        const QRectF rect = boundingRect();

        if (m_IsFlipped) {
            v[0].x = rect.left();
            v[0].y = rect.top();
            v[1].x = rect.left() + rect.width()/2;
            v[1].y = rect.bottom();
            v[2].x = rect.right();
            v[2].y = rect.top();
        } else {
            v[0].x = rect.left();
            v[0].y = rect.bottom();
            v[1].x = rect.left() + rect.width()/2;
            v[1].y = rect.top();
            v[2].x = rect.right();
            v[2].y = rect.bottom();
        }

        geomnode->setGeometry(&m_Geometry);
        geomnode->setMaterial(&m_Material);

        n->appendChildNode(geomnode);
        return n;
    }

void compareSelectionNode(QSGNode *node, const QRectF &rect, int selectionId)
{
    QSGGeometryNode *geometryNode = static_cast<QSGGeometryNode *>(node);
    QSGGeometry *geometry = geometryNode->geometry();
    QCOMPARE(geometry->vertexCount(), 4);
    QCOMPARE(geometry->drawingMode(), (GLenum)GL_TRIANGLE_STRIP);
    OpaqueColoredPoint2DWithSize *data =
            static_cast<OpaqueColoredPoint2DWithSize *>(geometry->vertexData());
    float *lowerLeft = reinterpret_cast<float *>(data);
    float *lowerRight = reinterpret_cast<float *>(++data);
    float *upperLeft = reinterpret_cast<float *>(++data);
    float *upperRight = reinterpret_cast<float *>(++data);

    QCOMPARE(QRectF(QPointF(upperLeft[0], upperLeft[1]), QPointF(lowerRight[0], lowerRight[1])),
            rect);
    QCOMPARE(lowerRight[0], upperRight[0]);
    QCOMPARE(lowerRight[1], lowerLeft[1]);
    QCOMPARE(upperLeft[0], lowerLeft[0]);
    QCOMPARE(upperLeft[1], upperRight[1]);

    QCOMPARE(int(lowerLeft[4]), selectionId);
    QCOMPARE(int(lowerRight[4]), selectionId);
    QCOMPARE(int(upperLeft[4]), selectionId);
    QCOMPARE(int(upperRight[4]), selectionId);

    TimelineItemsMaterial *material = static_cast<TimelineItemsMaterial *>(
                geometryNode->material());
    QVERIFY(!(material->flags() & QSGMaterial::Blending));
}

QSGGeometryNode *TimelineNotesRenderPassState::createNode()
{
    QSGGeometryNode *node = new QSGGeometryNode;
    node->setGeometry(&m_nullGeometry);
    node->setMaterial(&m_material);
    node->setFlag(QSGNode::OwnedByParent, false);
    return node;
}

void BindlingLoopsGeometry::allocate(QSGMaterial *material)
{
    QSGGeometry *geometry = new QSGGeometry(BindlingLoopsGeometry::point2DWithOffset(),
                                            usedVertices);
    geometry->setIndexDataPattern(QSGGeometry::StaticPattern);
    geometry->setVertexDataPattern(QSGGeometry::StaticPattern);
    node = new QSGGeometryNode;
    node->setGeometry(geometry);
    node->setFlag(QSGNode::OwnsGeometry, true);
    node->setMaterial(material);
    allocatedVertices = usedVertices;
    usedVertices = 0;
}

QSGNode * QQuickLineItem::updatePaintNode(QSGNode *prev_node,
                                          UpdatePaintNodeData *upd_data)
{
    Q_UNUSED(upd_data);

    QSGGeometryNode * node = static_cast<QSGGeometryNode*>(prev_node);
    QSGGeometry * geometry = NULL;
    QSGFlatColorMaterial * material = NULL;

    if(!node) {
        // http://qt-project.org/doc/qt-5/qsggeometrynode.html
        node = new QSGGeometryNode;
        geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(),4);
        geometry->setDrawingMode(GL_TRIANGLE_STRIP);
        node->setGeometry(geometry);
        node->setFlag(QSGNode::OwnsGeometry);

        material = new QSGFlatColorMaterial;
        material->setColor(m_color);
        node->setMaterial(material);
        node->setFlag(QSGNode::OwnsMaterial);
    }
    else {
        geometry = node->geometry();
        geometry->allocate(4); // we have to call allocate to invalidate
                               // the older vertex buffer
        material = static_cast<QSGFlatColorMaterial*>(node->material());
    }

    // geometry
    std::vector<QPointF> list_vx;
    if(!calcTriStrip(list_vx)) {
        list_vx.clear();
        list_vx.push_back(QPointF(0,0));
        list_vx.push_back(QPointF(0,0));
        list_vx.push_back(QPointF(0,0));
        list_vx.push_back(QPointF(0,0));
    }

    QSGGeometry::Point2D * vertices =
            geometry->vertexDataAsPoint2D();

    for(size_t i=0; i < list_vx.size(); i++) {
        vertices[i].set(list_vx[i].x(),
                        list_vx[i].y());
    }

    node->markDirty(QSGNode::DirtyGeometry);

    // material
    material->setColor(m_color);
    node->markDirty(QSGNode::DirtyMaterial);

    return node;
}

QSGNode *PhosphorRender::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData *)
{
    if (!m_ybuffer) {
        return 0;
    }

    QSGGeometryNode *node = 0;
    QSGGeometry *geometry = 0;
    Material *material = 0;

    unsigned n_points;

    if (m_xbuffer) {
        n_points = std::min(m_xbuffer->size(), m_ybuffer->size());
    } else {
        n_points = m_ybuffer->countPointsBetween(m_xmin, m_xmax);
    }

    n_points = std::min(n_points,(unsigned) 65767);

    if (!oldNode) {
        node = new QSGGeometryNode;
        geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), n_points);
        geometry->setDrawingMode(GL_POINTS);
        node->setGeometry(geometry);
        node->setFlag(QSGNode::OwnsGeometry);
        material = new Material;
        material->setFlag(QSGMaterial::Blending);
        node->setMaterial(material);
        node->setFlag(QSGNode::OwnsMaterial);
    } else {
        node = static_cast<QSGGeometryNode *>(oldNode);
        geometry = node->geometry();
        geometry->allocate(n_points);
        geometry->setLineWidth(m_pointSize);
        material = static_cast<Material*>(node->material());
    }

    QRectF bounds = boundingRect();

    material->transformation.setToIdentity();
    material->transformation.scale(bounds.width()/(m_xmax - m_xmin), bounds.height()/(m_ymin - m_ymax));
    material->transformation.translate(-m_xmin, -m_ymax);

    material->pointSize = m_pointSize;
    material->color = m_color;

    auto verticies = geometry->vertexDataAsPoint2D();
    if (m_xbuffer) {
        for (unsigned i=0; i<n_points; i++) {
            verticies[i].set(m_xbuffer->get(i), m_ybuffer->get(i));
        }
    } else {
        m_ybuffer->toVertexData(m_xmin, m_xmax, verticies, n_points);
    }
    node->markDirty(QSGNode::DirtyGeometry | QSGNode::DirtyMaterial);

    return node;
}

QSGNode *Canvas::updatePaintNode(QSGNode *n, UpdatePaintNodeData *d)
{
    QSGGeometryNode *node = static_cast<QSGGeometryNode*>(n);
    if (!node) node = new QSGGeometryNode();
    QSGGeometry::Point2D *v = m_Geometry.vertexDataAsPoint2D();
    const QRectF rect = boundingRect();
    v[0].x = rect.left();
    v[0].y = rect.bottom();
    v[1].x = rect.right();
    v[1].y = rect.bottom();
    v[2].x = rect.left();
    v[2].y = rect.top();
    v[3].x = rect.right();
    v[3].y = rect.top();
    node->setGeometry(&m_Geometry);
    node->setMaterial(&m_Material);
    return node;
}

void SceneGraphDeviceContext::DrawPolygon(int n, vrv::Point points[], int xoffset, int yoffset, int)
{
    // Note: No support for vertex antialiasing. Use a top-level QQuickView with multisample antialiasing.
    // TODO: Add vertex antialiasing, refer to
    // 1) Qt sources for "void QSGBasicInternalRectangleNode::updateGeometry()" in
    // qtdeclarative/src/quick/scenegraph/qsgbasicinternalrectanglenode.cpp
    // 2) https://stackoverflow.com/questions/28125425/smooth-painting-in-custom-qml-element

    // TODO: This function only works for convex polygons. At the moment verovio calls this function only with n = 4.
    // Maybe this function should be renamed to DrawConvexPolygon

    vrv::Pen currentPen = m_penStack.top();

    QSGGeometry *geometry;
    geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), n);
    geometry->setDrawingMode(QSGGeometry::DrawTriangleStrip);

    QSGFlatColorMaterial *material = new QSGFlatColorMaterial;
    material->setColor(static_cast<QRgb>(currentPen.GetColour()));

    // Reorder points so that they can be drawn with DrawTriangleStrip.
    int counter1 = 0;
    int counter2 = n - 1;
    for (int i = 0; i < n; i++) {
        if (i % 2 == 0) {
            geometry->vertexDataAsPoint2D()[i].set(
                translateX(points[counter1].x + xoffset), translateY(points[counter1].y + yoffset));
            counter1++;
        }
        else {
            geometry->vertexDataAsPoint2D()[i].set(
                translateX(points[counter2].x + xoffset), translateY(points[counter2].y + yoffset));
            counter2--;
        }
    }

    QSGGeometryNode *node = new QSGGeometryNode;
    node->setGeometry(geometry);
    node->setFlag(QSGNode::OwnsGeometry);
    node->setMaterial(material);
    node->setFlag(QSGNode::OwnsMaterial);

    AddGeometryNode(node);
}

void Renderer::updateOpacities(QSGNode *node, qreal inheritedOpacity)
{
    if (node->isSubtreeBlocked())
        return;

    if (node->type() == QSGNode::OpacityNodeType) {
        QSGOpacityNode *on = static_cast<QSGOpacityNode *>(node);
        qreal combined = inheritedOpacity * on->opacity();
        on->setCombinedOpacity(combined);
        QSGNODE_TRAVERSE(node)
        updateOpacities(child, combined);
    } else {
        if (node->type() == QSGNode::GeometryNodeType) {
            QSGGeometryNode *gn = static_cast<QSGGeometryNode *>(node);
            gn->setInheritedOpacity(inheritedOpacity);
        }
        QSGNODE_TRAVERSE(node)
        updateOpacities(child, inheritedOpacity);
    }
}

/*------------------------------------------------------------------------------
|    OMX_CameraSurfaceElement::updatePaintNode
+-----------------------------------------------------------------------------*/
QSGNode* OMX_CameraSurfaceElement::updatePaintNode(QSGNode* oldNode, UpdatePaintNodeData*)
{
    QSGGeometryNode* node = 0;
    QSGGeometry* geometry = 0;

    if (!oldNode) {
        // Create the node.
        node = new QSGGeometryNode;
        geometry = new QSGGeometry(QSGGeometry::defaultAttributes_TexturedPoint2D(), 4);
        geometry->setDrawingMode(GL_TRIANGLE_STRIP);
        node->setGeometry(geometry);
        node->setFlag(QSGNode::OwnsGeometry);

        // TODO: Who is freeing this?
        // TODO: I cannot know the texture size here.
        QSGOpaqueTextureMaterial* material = new QSGOpaqueTextureMaterial;
        m_sgtexture = new OMX_SGTexture(0, QSize(640, 480));
        material->setTexture(m_sgtexture);
        node->setMaterial(material);
        node->setFlag(QSGNode::OwnsMaterial);

        QtConcurrent::run(this, &OMX_CameraSurfaceElement::videoAcquire);
    }
    else {
        node = static_cast<QSGGeometryNode*>(oldNode);
        geometry = node->geometry();
        geometry->allocate(4);

        // Update texture in the node if needed.
        QSGOpaqueTextureMaterial* material = (QSGOpaqueTextureMaterial*)node->material();
        QElapsedTimer timer;
        timer.start();
        QSGTexture* texture = window()->createTextureFromImage(m_frame);
        LOG_VERBOSE(LOG_TAG, "Timer tex: %lld.", timer.elapsed());
        material->setTexture(texture);
        m_semAcquire.release();
#if 0
        if (m_texture != (GLuint)material->texture()->textureId()) {
            // TODO: Does setTextureId frees the prev texture?
            // TODO: I should the given the texture size.
            LOG_ERROR(LOG_TAG, "Updating texture to %u!", m_texture);
            material = new QSGOpaqueTextureMaterial;
            m_sgtexture->setTexture(m_texture, QSize(1920, 1080));
        }
#endif
    }

    // Create the vertices and map to texture.
    QRectF bounds = boundingRect();
    QSGGeometry::TexturedPoint2D* vertices = geometry->vertexDataAsTexturedPoint2D();
    vertices[0].set(bounds.x(), bounds.y() + bounds.height(), 0.0f, 0.0f);
    vertices[1].set(bounds.x() + bounds.width(), bounds.y() + bounds.height(), 1.0f, 0.0f);
    vertices[2].set(bounds.x(), bounds.y(), 0.0f, 1.0f);
    vertices[3].set(bounds.x() + bounds.width(), bounds.y(), 1.0f, 1.0f);
    return node;
}

void PEQGraph::_drawHumpOutline(QSGNode * parentNode, int n, QColor color) {
    //Solid Outline
    QSGGeometryNode * lineNode = new QSGGeometryNode();
    QSGGeometry * lineGeom = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), (HorizontalDivisions));

    QSGFlatColorMaterial *material2 = new QSGFlatColorMaterial;

    material2->setColor(color);
    material2->setFlag(QSGMaterial::Blending);

    lineNode->setMaterial(material2);
    lineNode->setFlag(QSGNode::OwnsGeometry);
    lineNode->setFlag(QSGNode::OwnedByParent);
    lineNode->setFlag(QSGNode::OwnsMaterial);

    lineGeom->setDrawingMode(GL_LINE_STRIP);
    glLineWidth(2.0f);

    QSGGeometry::Point2D* point2 = lineGeom->vertexDataAsPoint2D();

    float left = graphToNodeX(xAxis.min);
    float width = graphToNodeX(xAxis.max) - graphToNodeX(xAxis.min);
    float stride = width / HorizontalDivisions;

    for (int i = 0; i < HorizontalDivisions; i++) {
        float x1 = left + (i)*stride;
        float y1 = graphToNodeY(computedData[i][n]);

        point2->set(x1, y1);
        point2++;
    }

    lineNode->setGeometry(lineGeom);
    parentNode->appendChildNode(lineNode);
}

QSGNode *QPScrollingCurve::updatePaintNode(QSGNode *oldNode, QQuickItem::UpdatePaintNodeData *)
{
    QSGGeometryNode *node = 0;
    QSGGeometry *geometry = 0;
    QSGFlatColorMaterial *material = 0;

    if (!oldNode) {
        node = new QSGGeometryNode;
        geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), m_data.size());
        geometry->setLineWidth(2);
        geometry->setDrawingMode(GL_LINE_STRIP);
        node->setGeometry(geometry);
        node->setFlag(QSGNode::OwnsGeometry);
        material = new QSGFlatColorMaterial;
        material->setColor(m_color);
        node->setMaterial(material);
        node->setFlag(QSGNode::OwnsMaterial);
        node->markDirty(QSGNode::DirtyMaterial);
    } else {
        node = static_cast<QSGGeometryNode *>(oldNode);
        geometry = node->geometry();
        geometry->allocate(m_data.size());
        material = static_cast<QSGFlatColorMaterial*>(node->material());
        if (material->color() != m_color) {
            material->setColor(m_color);
            node->markDirty(QSGNode::DirtyMaterial);
        }
    }

    QSGGeometry::Point2D *vertices = geometry->vertexDataAsPoint2D();

    for (uint i = 0; i < m_data.size(); ++i) {
        QPointF p(i, m_data[i]);
        vertices[i].set(p.x(), p.y());
    }

    node->markDirty(QSGNode::DirtyGeometry);

    return node;
}

    QSGNode *Circle::updatePaintNode(QSGNode *n, UpdatePaintNodeData *d)
    {
        QSGGeometryNode *node = static_cast<QSGGeometryNode*>(n);
        if (!node) node = new QSGGeometryNode();
        QSGGeometry::Point2D *v = m_Geometry.vertexDataAsPoint2D();
        const QRectF rect = boundingRect();
        QPointF center = rect.center();
        float   radius = rect.width()/2.f;
        int numPoints = m_Geometry.vertexCount();
        v[0].x = center.x();
        v[0].y = center.y();
        for ( int i=1;  i < numPoints; ++i )
        {
            float theta = i*2*M_PI/( numPoints - 2 );
            v[i].x = center.x() + radius*cos(theta);
            v[i].y = center.y() - radius*sin(theta);
        }

        node->setGeometry(&m_Geometry);
        node->setMaterial(&m_Material);
        return node;
    }

//! [4]
QSGNode *BezierCurve::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData *)
{
    QSGGeometryNode *node = 0;
    QSGGeometry *geometry = 0;

    if (!oldNode) {
        node = new QSGGeometryNode;
//! [4] //! [5]
        geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), m_segmentCount);
        geometry->setLineWidth(2);
        geometry->setDrawingMode(GL_LINE_STRIP);
        node->setGeometry(geometry);
        node->setFlag(QSGNode::OwnsGeometry);
//! [5] //! [6]
        QSGFlatColorMaterial *material = new QSGFlatColorMaterial;
        material->setColor(QColor(255, 0, 0));
        node->setMaterial(material);
        node->setFlag(QSGNode::OwnsMaterial);
//! [6] //! [7]
    } else {
        node = static_cast<QSGGeometryNode *>(oldNode);
        geometry = node->geometry();
        geometry->allocate(m_segmentCount);
    }
//! [7]

//! [8]
    QRectF bounds = boundingRect();
    QSGGeometry::Point2D *vertices = geometry->vertexDataAsPoint2D();
    for (int i = 0; i < m_segmentCount; ++i) {
        qreal t = i / qreal(m_segmentCount - 1);
        qreal invt = 1 - t;

        QPointF pos = invt * invt * invt * m_p1
                    + 3 * invt * invt * t * m_p2
                    + 3 * invt * t * t * m_p3
                    + t * t * t * m_p4;

        float x = bounds.x() + pos.x() * bounds.width();
        float y = bounds.y() + pos.y() * bounds.height();

        vertices[i].set(x, y);
    }
    node->markDirty(QSGNode::DirtyGeometry);
//! [8]


//! [9]
    return node;
}