forked from gwihlidal/QNodeView
/
QNodeViewCanvas.cpp
79 lines (61 loc) · 2.41 KB
/
QNodeViewCanvas.cpp
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/*!
@file QNodeViewCanvas.cpp
Copyright (c) 2014 Graham Wihlidal
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
@author Graham Wihlidal
@date January 19, 2014
*/
#include <QNodeViewCanvas.h>
#include <QVarLengthArray>
#include <QWheelEvent>
QNodeViewCanvas::QNodeViewCanvas(QGraphicsScene* scene, QWidget* parent)
: QGraphicsView(scene, parent)
{
setRenderHint(QPainter::Antialiasing, true);
}
QNodeViewCanvas::~QNodeViewCanvas()
{
}
void QNodeViewCanvas::contextMenuEvent(QContextMenuEvent* event)
{
Q_UNUSED(event); // QGraphicsSceneContextMenuEvent
}
void QNodeViewCanvas::drawBackground(QPainter* painter, const QRectF& rect)
{
// GW-TODO: Expose this to QStyle
painter->fillRect(rect, QBrush(QColor(50, 50, 50)));
const qint32 gridInterval = 50;
painter->setWorldMatrixEnabled(true);
// GW-TODO: Expose this to QStyle
QPen linePen(QColor(80, 80, 80), 1, Qt::DotLine, Qt::FlatCap, Qt::RoundJoin);
linePen.setCosmetic(true); // Performance optimization
painter->setPen(linePen);
const qreal left = qint32(rect.left()) - (qint32(rect.left()) % gridInterval);
const qreal top = qint32(rect.top()) - (qint32(rect.top()) % gridInterval);
QVarLengthArray<QLineF, 100> linesX;
for (qreal x = left; x < rect.right(); x += gridInterval)
linesX.append(QLineF(x, rect.top(), x, rect.bottom()));
QVarLengthArray<QLineF, 100> linesY;
for (qreal y = top; y < rect.bottom(); y += gridInterval)
linesY.append(QLineF(rect.left(), y, rect.right(), y));
painter->drawLines(linesX.data(), linesX.size());
painter->drawLines(linesY.data(), linesY.size());
}
void QNodeViewCanvas::wheelEvent(QWheelEvent *event)
{
this->setTransformationAnchor(QGraphicsView::AnchorUnderMouse);
double scaleFactor = 1.15;
if(event->delta() > 0) {
this-> scale(scaleFactor, scaleFactor);
} else {
this->scale(1.0 / scaleFactor, 1.0 / scaleFactor);
}
}