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#!/usr/bin/env python
#############################################################################
##
## Copyright (C) 2013 Riverbank Computing Limited.
## Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
##
## This file is part of the examples of PyQt.
##
## $QT_BEGIN_LICENSE:BSD$
## You may use this file under the terms of the BSD license as follows:
##
## "Redistribution and use in source and binary forms, with or without
## modification, are permitted provided that the following conditions are
## met:
## * Redistributions of source code must retain the above copyright
## notice, this list of conditions and the following disclaimer.
## * Redistributions in binary form must reproduce the above copyright
## notice, this list of conditions and the following disclaimer in
## the documentation and/or other materials provided with the
## distribution.
## * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
## of its contributors may be used to endorse or promote products derived
## from this software without specific prior written permission.
##
##
## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
## $QT_END_LICENSE$
##
#############################################################################
from PyQt5.QtCore import pyqtProperty, pyqtSignal, QPointF, QUrl
from PyQt5.QtGui import QColor, QGuiApplication
from PyQt5.QtQml import qmlRegisterType
from PyQt5.QtQuick import (QQuickItem, QQuickView, QSGFlatColorMaterial,
QSGGeometry, QSGGeometryNode, QSGNode)
import customgeometry_rc
class BezierCurve(QQuickItem):
p1Changed = pyqtSignal(QPointF)
@pyqtProperty(QPointF, notify=p1Changed)
def p1(self):
return self._p1
@p1.setter
def p1(self, p):
if self._p1 != p:
self._p1 = QPointF(p)
self.p1Changed.emit(p)
self.update()
p2Changed = pyqtSignal(QPointF)
@pyqtProperty(QPointF, notify=p2Changed)
def p2(self):
return self._p2
@p2.setter
def p2(self, p):
if self._p2 != p:
self._p2 = QPointF(p)
self.p2Changed.emit(p)
self.update()
p3Changed = pyqtSignal(QPointF)
@pyqtProperty(QPointF, notify=p3Changed)
def p3(self):
return self._p3
@p3.setter
def p3(self, p):
if self._p3 != p:
self._p3 = QPointF(p)
self.p3Changed.emit(p)
self.update()
p4Changed = pyqtSignal(QPointF)
@pyqtProperty(QPointF, notify=p4Changed)
def p4(self):
return self._p4
@p4.setter
def p4(self, p):
if self._p4 != p:
self._p4 = QPointF(p)
self.p4Changed.emit(p)
self.update()
segmentCountChanged = pyqtSignal(int)
@pyqtProperty(int, notify=segmentCountChanged)
def segmentCount(self):
return self._segmentCount
@segmentCount.setter
def segmentCount(self, count):
if self._segmentCount != count:
self._segmentCount = count
self.segmentCountChanged.emit(count)
self.update()
def __init__(self, parent=None):
super(BezierCurve, self).__init__(parent)
self._p1 = QPointF(0, 0)
self._p2 = QPointF(1, 0)
self._p3 = QPointF(0, 1)
self._p4 = QPointF(1, 1)
self._segmentCount = 32
self._root_node = None
self.setFlag(QQuickItem.ItemHasContents, True)
def updatePaintNode(self, oldNode, nodeData):
if self._root_node is None:
self._root_node = QSGGeometryNode()
geometry = QSGGeometry(QSGGeometry.defaultAttributes_Point2D(),
self._segmentCount)
geometry.setLineWidth(2)
geometry.setDrawingMode(QSGGeometry.GL_LINE_STRIP)
self._root_node.setGeometry(geometry)
self._root_node.setFlag(QSGNode.OwnsGeometry)
material = QSGFlatColorMaterial()
material.setColor(QColor(255, 0, 0))
self._root_node.setMaterial(material)
self._root_node.setFlag(QSGNode.OwnsMaterial)
else:
geometry = self._root_node.geometry()
geometry.allocate(self._segmentCount)
w = self.width()
h = self.height()
vertices = geometry.vertexDataAsPoint2D()
for i in range(self._segmentCount):
t = i / float(self._segmentCount - 1)
invt = 1 - t
pos = invt * invt * invt * self._p1 \
+ 3 * invt * invt * t * self._p2 \
+ 3 * invt * t * t * self._p3 \
+ t * t * t * self._p4
vertices[i].set(pos.x() * w, pos.y() * h)
self._root_node.markDirty(QSGNode.DirtyGeometry)
return self._root_node
if __name__ == '__main__':
import sys
app = QGuiApplication(sys.argv)
qmlRegisterType(BezierCurve, "CustomGeometry", 1, 0, "BezierCurve")
view = QQuickView()
format = view.format()
format.setSamples(16)
view.setFormat(format)
view.setSource(QUrl('qrc:///scenegraph/customgeometry/main.qml'))
view.show()
sys.exit(app.exec_())
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