I want to draw a rectangle from the center of it like the below situation.
The image of rectangle:
painter.rectMode(Center)
painter.drawRect(x, y, w, h)
How I can do that task?
I want to draw a rectangle from the center. Please help me.
It is a simple geometry calculus that can handle by a simple function
from PyQt6.QtGui import QPaintEvent, QPainter, QPen, QBrush, QColor
from PyQt6.QtWidgets import QWidget, QApplication
from PyQt6.QtCore import Qt
from sys import argv, exit
class Window(QWidget):
def __init__(self, parent=None) -> None:
super().__init__(parent)
self.screen_width = 1920
self.screen_height = 1080
self.window_width = 700
self.window_height = 400
self.setGeometry(
(self.screen_width - self.window_width) // 2,
(self.screen_height - self.window_height) // 2,
self.window_width,
self.window_height,
)
self.show()
def drawRectFromCenter(self, x, y, w, h):
return x - w // 2, y - h // 2, w, h
def paintEvent(self, a0: QPaintEvent | None) -> None:
painter = QPainter()
painter.begin(self)
painter.setPen(QPen(QColor(0, 0, 0), 0, Qt.PenStyle.SolidLine))
# draw rectangle from top-left corner
x_from_top_left = 100
y_from_top_left = 100
w_from_top_left = 200
h_from_top_left = 200
r_from_top_left = 10
painter.setBrush(QBrush(QColor(0, 255, 0), Qt.BrushStyle.SolidPattern))
painter.drawRect(
x_from_top_left, y_from_top_left, w_from_top_left, h_from_top_left
)
painter.setBrush(QBrush(QColor(255, 0, 0, 128), Qt.BrushStyle.SolidPattern))
painter.drawEllipse(
x_from_top_left - r_from_top_left // 2,
y_from_top_left - r_from_top_left // 2,
r_from_top_left,
r_from_top_left,
)
# draw rectangle from center
x_from_center = 500
y_from_center = 200
w_from_center = 200
h_from_center = 200
r_from_center = 10
painter.setBrush(QBrush(QColor(0, 255, 0), Qt.BrushStyle.SolidPattern))
x, y, w, h = self.drawRectFromCenter(
x_from_center, y_from_center, w_from_center, h_from_center
)
painter.drawRect(x, y, w, h)
painter.setBrush(QBrush(QColor(255, 0, 0, 128), Qt.BrushStyle.SolidPattern))
painter.drawEllipse(
x_from_center - r_from_center // 2,
y_from_center - r_from_center // 2,
r_from_center,
r_from_center,
)
return super().paintEvent(a0)
if __name__ == "__main__":
App = QApplication(argv)
window = Window()
exit(App.exec())
The window will look like this.