[FIXED] Pyqtgraph plotting is slow

Issue

It seems window redraws everything each time new rect is added, although setUpdatesEnabled is set to False, for win and plt. How to disable updates?

def f(n):
    import pyqtgraph as pg
    pg.setConfigOption('background', '#a0f0ff')
    win = pg.GraphicsWindow()
    win_size = 1000
    win.setGeometry(500, 30, win_size, win_size)
    plt = win.addPlot()
    win.setUpdatesEnabled = False
    plt.setUpdatesEnabled = False
    y = range(n)
    x = range(n)
    plt.showGrid(x=True, y=True)
    empty_pen = pg.mkPen((0, 0, 0, 0))
    brush = pg.mkBrush((255, 255, 255))
    for i1 in range(n):
        for i0 in range(n):
            print("i1, i0 =", i1, i0)
            rect = pg.QtGui.QGraphicsRectItem(i0, i1, 0.5, 0.5)
            rect.setPen(empty_pen)
            rect.setBrush(brush)
            plt.addItem(rect)
    pg.QtGui.QApplication.exec_()

f(40)

Solution

Add

plt.disableAutoRange()

before drawing and

plt.autoRange()

after it. See Plotting large arrays in pyqtgraph

Answered By - DSblizzard