[Python] Is there a way to bind multiple related `pyqtgraph.opengl.GLLinePlotItem` objects to...

Let's say I have two pyqtgraph.opengl.GLLinePlotItem objects in a pyqtgraph.opengl.GLViewWidget view, where the 2nd line's coordinates depend on the 1st line's coordinates. In the code below, the position of the 2nd line has an offset of +1.

Is there a way to bind the two objects where it optimizes the rendering process such that you don't have to call setData() for the 2nd line? So in the code below, you wouldn't need to have self.line2.setData(pos=self.pos2), it would automatically render the adjusted position.

I was thinking there might be a way by overriding the GLViewWidget.paintGL() method and then paint it directly with PySide6.QtGui.QPainter(), and not having a GLLinePlotItem for line 2 at all, but I wasn't sure how to do that...

import sys
import numpy as np
from PySide6 import QtWidgets, QtCore
import pyqtgraph.opengl as gl

class MainWindow(QtWidgets.QMainWindow):
def __init__(self):
super().__init__()
self.setWindowTitle("OpenGL Line Example")
self.resize(800, 600)
self.timer = QtCore.QTimer(self)
self.timer.setInterval(500)
self.timer.timeout.connect(self.updateData)
self.timer.start()
self.gl_view = gl.GLViewWidget()
self.setCentralWidget(self.gl_view)
self.x = np.linspace(-1, 1, 100)
self.y = np.linspace(-1, 1, 100)
self.z = np.zeros_like(self.x)
self.pos1 = np.column_stack((self.x, self.y, self.z))
self.pos2 = np.column_stack((self.x+1, self.y+1, self.z+1))
self.line1 = gl.GLLinePlotItem(pos=self.pos1, color=(1, 1, 0, 1), width=2)
self.line2 = gl.GLLinePlotItem(pos=self.pos2, color=(1, 0, 0, 1), width=2)
self.gl_view.addItem(self.line1)
self.gl_view.addItem(self.line2)

def updateData(self):
self.z += np.random.normal(0, 0.5)

self.pos1[:,2] = self.z
self.pos2[:,2] = self.z + 1

self.line1.setData(pos=self.pos1)
self.line2.setData(pos=self.pos2)

if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec())

Continue reading...