ScatterPlotItem.py 文件源码

def renderSymbol(symbol, size, pen, brush, device=None):
    """
    Render a symbol specification to QImage.
    Symbol may be either a QPainterPath or one of the keys in the Symbols dict.
    If *device* is None, a new QPixmap will be returned. Otherwise,
    the symbol will be rendered into the device specified (See QPainter documentation
    for more information).
    """
    ## Render a spot with the given parameters to a pixmap
    penPxWidth = max(np.ceil(pen.widthF()), 1)
    if device is None:
        device = QtGui.QImage(int(size+penPxWidth), int(size+penPxWidth), QtGui.QImage.Format_ARGB32)
        device.fill(0)
    p = QtGui.QPainter(device)
    try:
        p.setRenderHint(p.Antialiasing)
        p.translate(device.width()*0.5, device.height()*0.5)
        drawSymbol(p, symbol, size, pen, brush)
    finally:
        p.end()
    return device