Added graphics item for drawing filled space between two plots

graphicsItems/FillBetweenItem.py

@@ -0,0 +1,23 @@
+import pyqtgraph as pg
+
+class FillBetweenItem(pg.QtGui.QGraphicsPathItem):
+    """
+    GraphicsItem filling the space between two PlotDataItems.
+    """
+    def __init__(self, p1, p2, brush=None):
+        pg.QtGui.QGraphicsPathItem.__init__(self)
+        self.p1 = p1
+        self.p2 = p2
+        p1.sigPlotChanged.connect(self.updatePath)
+        p2.sigPlotChanged.connect(self.updatePath)
+        if brush is not None:
+            self.setBrush(pg.mkBrush(brush))
+        self.setZValue(min(p1.zValue(), p2.zValue())-1)
+        self.updatePath()
+
+    def updatePath(self):
+        p1 = self.p1.curve.path
+        p2 = self.p2.curve.path
+        path = pg.QtGui.QPainterPath()
+        path.addPolygon(p1.toSubpathPolygons()[0] + p2.toReversed().toSubpathPolygons()[0])
+        self.setPath(path)