Carolina5
26th October 2020, 17:30
I’m writing an application in PyQt5 that will allow the user to rotate a QGraphicsPixmapItem and also delete it. The rotation needs to be with the mouse via a rotation handle that the user can grab with the mouse and rotate, thus rotating the QGraphicsPixmapItem. I need the handle to have a fixed distance to the item position, precisely to be at the top left corner of the QGraphicsPixmapItem. Also, I need the handle to be a child of the graphic pixmap item so that when the user moves the image or deletes it, the handle will be moved or deleted too.
I based my code on this answer https://stackoverflow.com/questions/11147443/rotate-qgraphicspixmapitem-with-mouse
I have some troubles, when I do not set the handle as a child of the graphic pixmap item, the rotation is fine but not the part of moving the handle when the user moves the image. When I set the handle as a child, the rotation doesn’t work as I want.
Could someone help me please? This is my code:
import sys
from PyQt5.QtWidgets import QMainWindow, QApplication, QGraphicsView
from PyQt5 import QtGui, QtWidgets
import math
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.scene = Scene()
self.view = QGraphicsView(self)
self.setGeometry(10, 30, 850, 600)
self.view.setGeometry(20, 22, 800, 550)
self.view.setScene(self.scene)
class Scene(QtWidgets.QGraphicsScene):
def __init__(self, parent=None):
super(Scene, self).__init__(parent)
# other stuff here
self.set_image()
def set_image(self):
photo = Photo()
self.addItem(photo)
photo.set_pixmap()
class Photo(QtWidgets.QGraphicsPixmapItem):
def __init__(self, parent=None):
super(Photo, self).__init__(parent)
self.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable , True)
self.setTransformOriginPoint(self.boundingRect().c enter())
def set_pixmap(self):
pixmap = QtGui.QPixmap("perro.jpg")
self.setPixmap(pixmap)
self.pixmap_controller = PixmapController(self)
self.pixmap_controller.set_pixmap_controller()
self.pixmap_controller.setPos(self.boundingRect(). topLeft())
self.pixmap_controller.setFlag(QtWidgets.QGraphics Item.ItemSendsScenePositionChanges, True)
def rotate_item(self, position):
item_position = self.transformOriginPoint()
angle = math.atan2(item_position.y() - position.y(), item_position.x() - position.x()) / math.pi * 180 - 45
print(angle)
self.setRotation(angle)
self.setPos(position)
class PixmapController(QtWidgets.QGraphicsEllipseItem):
def __init__(self, pixmap):
super(PixmapController, self).__init__(parent=pixmap)
self.pixmap = pixmap
self.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable , True)
color = QtGui.QColor(0, 0, 0)
brush = QtGui.QBrush(color)
self.setBrush(brush)
def set_pixmap_controller(self):
self.setRect(-5, -5, 10, 10)
def itemChange(self, change, value):
if change == QtWidgets.QGraphicsItem.ItemPositionChange:
self.pixmap.rotate_item(value)
return super(PixmapController, self).itemChange(change, value)
if __name__ == "__main__":
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())
I based my code on this answer https://stackoverflow.com/questions/11147443/rotate-qgraphicspixmapitem-with-mouse
I have some troubles, when I do not set the handle as a child of the graphic pixmap item, the rotation is fine but not the part of moving the handle when the user moves the image. When I set the handle as a child, the rotation doesn’t work as I want.
Could someone help me please? This is my code:
import sys
from PyQt5.QtWidgets import QMainWindow, QApplication, QGraphicsView
from PyQt5 import QtGui, QtWidgets
import math
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.scene = Scene()
self.view = QGraphicsView(self)
self.setGeometry(10, 30, 850, 600)
self.view.setGeometry(20, 22, 800, 550)
self.view.setScene(self.scene)
class Scene(QtWidgets.QGraphicsScene):
def __init__(self, parent=None):
super(Scene, self).__init__(parent)
# other stuff here
self.set_image()
def set_image(self):
photo = Photo()
self.addItem(photo)
photo.set_pixmap()
class Photo(QtWidgets.QGraphicsPixmapItem):
def __init__(self, parent=None):
super(Photo, self).__init__(parent)
self.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable , True)
self.setTransformOriginPoint(self.boundingRect().c enter())
def set_pixmap(self):
pixmap = QtGui.QPixmap("perro.jpg")
self.setPixmap(pixmap)
self.pixmap_controller = PixmapController(self)
self.pixmap_controller.set_pixmap_controller()
self.pixmap_controller.setPos(self.boundingRect(). topLeft())
self.pixmap_controller.setFlag(QtWidgets.QGraphics Item.ItemSendsScenePositionChanges, True)
def rotate_item(self, position):
item_position = self.transformOriginPoint()
angle = math.atan2(item_position.y() - position.y(), item_position.x() - position.x()) / math.pi * 180 - 45
print(angle)
self.setRotation(angle)
self.setPos(position)
class PixmapController(QtWidgets.QGraphicsEllipseItem):
def __init__(self, pixmap):
super(PixmapController, self).__init__(parent=pixmap)
self.pixmap = pixmap
self.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable , True)
color = QtGui.QColor(0, 0, 0)
brush = QtGui.QBrush(color)
self.setBrush(brush)
def set_pixmap_controller(self):
self.setRect(-5, -5, 10, 10)
def itemChange(self, change, value):
if change == QtWidgets.QGraphicsItem.ItemPositionChange:
self.pixmap.rotate_item(value)
return super(PixmapController, self).itemChange(change, value)
if __name__ == "__main__":
app = QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec_())