Merge branch 'develop' into image-testing

Conflicts:
	pyqtgraph/tests/__init__.py

examples/InfiniteLine.py

@@ -0,0 +1,45 @@
+# -*- coding: utf-8 -*-
+"""
+This example demonstrates some of the plotting items available in pyqtgraph.
+"""
+
+import initExample ## Add path to library (just for examples; you do not need this)
+from pyqtgraph.Qt import QtGui, QtCore
+import numpy as np
+import pyqtgraph as pg
+
+
+app = QtGui.QApplication([])
+win = pg.GraphicsWindow(title="Plotting items examples")
+win.resize(1000,600)
+
+# Enable antialiasing for prettier plots
+pg.setConfigOptions(antialias=True)
+
+# Create a plot with some random data
+p1 = win.addPlot(title="Plot Items example", y=np.random.normal(size=100, scale=10), pen=0.5)
+p1.setYRange(-40, 40)
+
+# Add three infinite lines with labels
+inf1 = pg.InfiniteLine(movable=True, angle=90, label='x={value:0.2f}', 
+                       labelOpts={'position':0.1, 'color': (200,200,100), 'fill': (200,200,200,50), 'movable': True})
+inf2 = pg.InfiniteLine(movable=True, angle=0, pen=(0, 0, 200), bounds = [-20, 20], hoverPen=(0,200,0), label='y={value:0.2f}mm', 
+                       labelOpts={'color': (200,0,0), 'movable': True, 'fill': (0, 0, 200, 100)})
+inf3 = pg.InfiniteLine(movable=True, angle=45, pen='g', label='diagonal',
+                       labelOpts={'rotateAxis': [1, 0], 'fill': (0, 200, 0, 100), 'movable': True})
+inf1.setPos([2,2])
+p1.addItem(inf1)
+p1.addItem(inf2)
+p1.addItem(inf3)
+
+# Add a linear region with a label
+lr = pg.LinearRegionItem(values=[70, 80])
+p1.addItem(lr)
+label = pg.InfLineLabel(lr.lines[1], "region 1", position=0.95, rotateAxis=(1,0), anchor=(1, 1))
+
+
+## Start Qt event loop unless running in interactive mode or using pyside.
+if __name__ == '__main__':
+    import sys
+    if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
+        QtGui.QApplication.instance().exec_()

examples/Symbols.py

@@ -0,0 +1,38 @@
+# -*- coding: utf-8 -*-
+"""
+This example shows all the scatter plot symbols available in pyqtgraph.
+
+These symbols are used to mark point locations for scatter plots and some line
+plots, similar to "markers" in matplotlib and vispy.
+"""
+
+import initExample ## Add path to library (just for examples; you do not need this)
+from pyqtgraph.Qt import QtGui, QtCore
+import pyqtgraph as pg
+
+app = QtGui.QApplication([])
+win = pg.GraphicsWindow(title="Scatter Plot Symbols")
+win.resize(1000,600)
+
+pg.setConfigOptions(antialias=True)
+
+plot = win.addPlot(title="Plotting with symbols")
+plot.addLegend()
+plot.plot([0, 1, 2, 3, 4], pen=(0,0,200), symbolBrush=(0,0,200), symbolPen='w', symbol='o', symbolSize=14, name="symbol='o'")
+plot.plot([1, 2, 3, 4, 5], pen=(0,128,0), symbolBrush=(0,128,0), symbolPen='w', symbol='t', symbolSize=14, name="symbol='t'")
+plot.plot([2, 3, 4, 5, 6], pen=(19,234,201), symbolBrush=(19,234,201), symbolPen='w', symbol='t1', symbolSize=14, name="symbol='t1'")
+plot.plot([3, 4, 5, 6, 7], pen=(195,46,212), symbolBrush=(195,46,212), symbolPen='w', symbol='t2', symbolSize=14, name="symbol='t2'")
+plot.plot([4, 5, 6, 7, 8], pen=(250,194,5), symbolBrush=(250,194,5), symbolPen='w', symbol='t3', symbolSize=14, name="symbol='t3'")
+plot.plot([5, 6, 7, 8, 9], pen=(54,55,55), symbolBrush=(55,55,55), symbolPen='w', symbol='s', symbolSize=14, name="symbol='s'")
+plot.plot([6, 7, 8, 9, 10], pen=(0,114,189), symbolBrush=(0,114,189), symbolPen='w', symbol='p', symbolSize=14, name="symbol='p'")
+plot.plot([7, 8, 9, 10, 11], pen=(217,83,25), symbolBrush=(217,83,25), symbolPen='w', symbol='h', symbolSize=14, name="symbol='h'")
+plot.plot([8, 9, 10, 11, 12], pen=(237,177,32), symbolBrush=(237,177,32), symbolPen='w', symbol='star', symbolSize=14, name="symbol='star'")
+plot.plot([9, 10, 11, 12, 13], pen=(126,47,142), symbolBrush=(126,47,142), symbolPen='w', symbol='+', symbolSize=14, name="symbol='+'")
+plot.plot([10, 11, 12, 13, 14], pen=(119,172,48), symbolBrush=(119,172,48), symbolPen='w', symbol='d', symbolSize=14, name="symbol='d'")
+plot.setXRange(-2, 4)
+
+## Start Qt event loop unless running in interactive mode or using pyside.
+if __name__ == '__main__':
+    import sys
+    if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
+        QtGui.QApplication.instance().exec_()

examples/infiniteline_performance.py

@@ -0,0 +1,52 @@
+#!/usr/bin/python
+
+import initExample ## Add path to library (just for examples; you do not need this)
+from pyqtgraph.Qt import QtGui, QtCore
+import numpy as np
+import pyqtgraph as pg
+from pyqtgraph.ptime import time
+app = QtGui.QApplication([])
+
+p = pg.plot()
+p.setWindowTitle('pyqtgraph performance: InfiniteLine')
+p.setRange(QtCore.QRectF(0, -10, 5000, 20))
+p.setLabel('bottom', 'Index', units='B')
+curve = p.plot()
+
+# Add a large number of horizontal InfiniteLine to plot
+for i in range(100):
+    line = pg.InfiniteLine(pos=np.random.randint(5000), movable=True)
+    p.addItem(line)
+
+data = np.random.normal(size=(50, 5000))
+ptr = 0
+lastTime = time()
+fps = None
+
+
+def update():
+    global curve, data, ptr, p, lastTime, fps
+    curve.setData(data[ptr % 10])
+    ptr += 1
+    now = time()
+    dt = now - lastTime
+    lastTime = now
+    if fps is None:
+        fps = 1.0/dt
+    else:
+        s = np.clip(dt*3., 0, 1)
+        fps = fps * (1-s) + (1.0/dt) * s
+    p.setTitle('%0.2f fps' % fps)
+    app.processEvents()  # force complete redraw for every plot
+
+
+timer = QtCore.QTimer()
+timer.timeout.connect(update)
+timer.start(0)
+
+
+# Start Qt event loop unless running in interactive mode.
+if __name__ == '__main__':
+    import sys
+    if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
+        QtGui.QApplication.instance().exec_()

examples/text.py

@@ -23,7 +23,7 @@ plot.setWindowTitle('pyqtgraph example: text')
 curve = plot.plot(x,y)  ## add a single curve
 
 ## Create text object, use HTML tags to specify color/size
-text = pg.TextItem(html='<div style="text-align: center"><span style="color: #FFF;">This is the</span><br><span style="color: #FF0; font-size: 16pt;">PEAK</span></div>', anchor=(-0.3,1.3), border='w', fill=(0, 0, 255, 100))
+text = pg.TextItem(html='<div style="text-align: center"><span style="color: #FFF;">This is the</span><br><span style="color: #FF0; font-size: 16pt;">PEAK</span></div>', anchor=(-0.3,0.5), angle=45, border='w', fill=(0, 0, 255, 100))
 plot.addItem(text)
 text.setPos(0, y.max())
 

examples/utils.py

@@ -22,6 +22,7 @@ examples = OrderedDict([
     ('Console', 'ConsoleWidget.py'),
     ('Histograms', 'histogram.py'),
     ('Beeswarm plot', 'beeswarm.py'),
+    ('Symbols', 'Symbols.py'),
     ('Auto-range', 'PlotAutoRange.py'),
     ('Remote Plotting', 'RemoteSpeedTest.py'),
     ('Scrolling plots', 'scrollingPlots.py'),

pyqtgraph/GraphicsScene/GraphicsScene.py

@@ -98,6 +98,7 @@ class GraphicsScene(QtGui.QGraphicsScene):
         self.lastDrag = None
         self.hoverItems = weakref.WeakKeyDictionary()
         self.lastHoverEvent = None
+        self.minDragTime = 0.5  # drags shorter than 0.5 sec are interpreted as clicks
         
         self.contextMenu = [QtGui.QAction("Export...", self)]
         self.contextMenu[0].triggered.connect(self.showExportDialog)
@@ -173,7 +174,7 @@ class GraphicsScene(QtGui.QGraphicsScene):
                     if int(btn) not in self.dragButtons:  ## see if we've dragged far enough yet
                         cev = [e for e in self.clickEvents if int(e.button()) == int(btn)][0]
                         dist = Point(ev.screenPos() - cev.screenPos())
-                        if dist.length() < self._moveDistance and now - cev.time() < 0.5:
+                        if dist.length() < self._moveDistance and now - cev.time() < self.minDragTime:
                             continue
                         init = init or (len(self.dragButtons) == 0)  ## If this is the first button to be dragged, then init=True
                         self.dragButtons.append(int(btn))
@@ -187,9 +188,7 @@ class GraphicsScene(QtGui.QGraphicsScene):
         if len(self.dragButtons) == 0:
             self.sendHoverEvents(ev, exitOnly=True)
                 
-                
     def mouseReleaseEvent(self, ev):
-        #print 'sceneRelease'
         if self.mouseGrabberItem() is None:
             if ev.button() in self.dragButtons:
                 if self.sendDragEvent(ev, final=True):

pyqtgraph/Qt.py

@@ -9,7 +9,7 @@ This module exists to smooth out some of the differences between PySide and PyQt
 
 """
 
-import sys, re
+import sys, re, time
 
 from .python2_3 import asUnicode
 
@@ -45,6 +45,15 @@ if QT_LIB == PYSIDE:
     from PySide import QtGui, QtCore, QtOpenGL, QtSvg
     try:
         from PySide import QtTest
+        if not hasattr(QtTest.QTest, 'qWait'):
+            @staticmethod
+            def qWait(msec):
+                start = time.time()
+                QtGui.QApplication.processEvents()
+                while time.time() < start + msec * 0.001:
+                    QtGui.QApplication.processEvents()
+            QtTest.QTest.qWait = qWait
+                
     except ImportError:
         pass
     import PySide

pyqtgraph/graphicsItems/InfiniteLine.py

@@ -1,12 +1,16 @@
 from ..Qt import QtGui, QtCore
 from ..Point import Point
 from .GraphicsObject import GraphicsObject
+from .TextItem import TextItem
+from .ViewBox import ViewBox
 from .. import functions as fn
 import numpy as np
 import weakref
 
 
-__all__ = ['InfiniteLine']
+__all__ = ['InfiniteLine', 'InfLineLabel']
+
+
 class InfiniteLine(GraphicsObject):
     """
     **Bases:** :class:`GraphicsObject <pyqtgraph.GraphicsObject>`
@@ -26,7 +30,8 @@ class InfiniteLine(GraphicsObject):
     sigPositionChangeFinished = QtCore.Signal(object)
     sigPositionChanged = QtCore.Signal(object)
 
-    def __init__(self, pos=None, angle=90, pen=None, movable=False, bounds=None):
+    def __init__(self, pos=None, angle=90, pen=None, movable=False, bounds=None,
+                 hoverPen=None, label=None, labelOpts=None, name=None):
         """
         =============== ==================================================================
         **Arguments:**
@@ -37,10 +42,23 @@ class InfiniteLine(GraphicsObject):
                         for :func:`mkPen <pyqtgraph.mkPen>`. Default pen is transparent
                         yellow.
         movable         If True, the line can be dragged to a new position by the user.
+        hoverPen        Pen to use when drawing line when hovering over it. Can be any
+                        arguments that are valid for :func:`mkPen <pyqtgraph.mkPen>`.
+                        Default pen is red.
         bounds          Optional [min, max] bounding values. Bounds are only valid if the
                         line is vertical or horizontal.
+        label           Text to be displayed in a label attached to the line, or
+                        None to show no label (default is None). May optionally
+                        include formatting strings to display the line value.
+        labelOpts       A dict of keyword arguments to use when constructing the
+                        text label. See :class:`InfLineLabel`.
+        name            Name of the item
         =============== ==================================================================
         """
+        self._boundingRect = None
+        self._line = None
+
+        self._name = name
 
         GraphicsObject.__init__(self)
 
@@ -53,17 +71,24 @@ class InfiniteLine(GraphicsObject):
         self.mouseHovering = False
         self.p = [0, 0]
         self.setAngle(angle)
+
         if pos is None:
             pos = Point(0,0)
         self.setPos(pos)
 
         if pen is None:
             pen = (200, 200, 100)
-        
         self.setPen(pen)
+        if hoverPen is None:
             self.setHoverPen(color=(255,0,0), width=self.pen.width())
+        else:
+            self.setHoverPen(hoverPen)
         self.currentPen = self.pen
         
+        if label is not None:
+            labelOpts = {} if labelOpts is None else labelOpts
+            self.label = InfLineLabel(self, text=label, **labelOpts)
+
     def setMovable(self, m):
         """Set whether the line is movable by the user."""
         self.movable = m
@@ -136,8 +161,8 @@ class InfiniteLine(GraphicsObject):
 
         if self.p != newPos:
             self.p = newPos
+            self._invalidateCache()
             GraphicsObject.setPos(self, Point(self.p))
-            self.update()
             self.sigPositionChanged.emit(self)
 
     def getXPos(self):
@@ -175,23 +200,33 @@ class InfiniteLine(GraphicsObject):
             #print "ignore", change
         #return GraphicsObject.itemChange(self, change, val)
 
+    def _invalidateCache(self):
+        self._line = None
+        self._boundingRect = None
+
     def boundingRect(self):
+        if self._boundingRect is None:
             #br = UIGraphicsItem.boundingRect(self)
             br = self.viewRect()
-        ## add a 4-pixel radius around the line for mouse interaction.
+            if br is None:
+                return QtCore.QRectF()
             
+            ## add a 4-pixel radius around the line for mouse interaction.
             px = self.pixelLength(direction=Point(1,0), ortho=True)  ## get pixel length orthogonal to the line
             if px is None:
                 px = 0
             w = (max(4, self.pen.width()/2, self.hoverPen.width()/2)+1) * px
             br.setBottom(-w)
             br.setTop(w)
-        return br.normalized()
+            
+            br = br.normalized()
+            self._boundingRect = br
+            self._line = QtCore.QLineF(br.right(), 0.0, br.left(), 0.0)
+        return self._boundingRect
 
     def paint(self, p, *args):
-        br = self.boundingRect()
         p.setPen(self.currentPen)
-        p.drawLine(Point(br.right(), 0), Point(br.left(), 0))
+        p.drawLine(self._line)
 
     def dataBounds(self, axis, frac=1.0, orthoRange=None):
         if axis == 0:
@@ -240,3 +275,195 @@ class InfiniteLine(GraphicsObject):
         else:
             self.currentPen = self.pen
         self.update()
+
+    def viewTransformChanged(self):
+        """
+        Called whenever the transformation matrix of the view has changed.
+        (eg, the view range has changed or the view was resized)
+        """
+        self._invalidateCache()
+        
+    def setName(self, name):
+        self._name = name
+
+    def name(self):
+        return self._name
+
+
+class InfLineLabel(TextItem):
+    """
+    A TextItem that attaches itself to an InfiniteLine.
+    
+    This class extends TextItem with the following features:
+    
+    * Automatically positions adjacent to the line at a fixed position along
+      the line and within the view box.
+    * Automatically reformats text when the line value has changed.
+    * Can optionally be dragged to change its location along the line.
+    * Optionally aligns to its parent line.
+
+    =============== ==================================================================
+    **Arguments:**
+    line            The InfiniteLine to which this label will be attached.
+    text            String to display in the label. May contain a {value} formatting
+                    string to display the current value of the line.
+    movable         Bool; if True, then the label can be dragged along the line.
+    position        Relative position (0.0-1.0) within the view to position the label
+                    along the line.
+    anchors         List of (x,y) pairs giving the text anchor positions that should
+                    be used when the line is moved to one side of the view or the
+                    other. This allows text to switch to the opposite side of the line
+                    as it approaches the edge of the view. These are automatically
+                    selected for some common cases, but may be specified if the 
+                    default values give unexpected results.
+    =============== ==================================================================
+    
+    All extra keyword arguments are passed to TextItem. A particularly useful
+    option here is to use `rotateAxis=(1, 0)`, which will cause the text to
+    be automatically rotated parallel to the line.
+    """
+    def __init__(self, line, text="", movable=False, position=0.5, anchors=None, **kwds):
+        self.line = line
+        self.movable = movable
+        self.orthoPos = position  # text will always be placed on the line at a position relative to view bounds
+        self.format = text
+        self.line.sigPositionChanged.connect(self.valueChanged)
+        self._endpoints = (None, None)
+        if anchors is None:
+            # automatically pick sensible anchors
+            rax = kwds.get('rotateAxis', None)
+            if rax is not None:
+                if tuple(rax) == (1,0):
+                    anchors = [(0.5, 0), (0.5, 1)]
+                else:
+                    anchors = [(0, 0.5), (1, 0.5)]
+            else:
+                if line.angle % 180 == 0:
+                    anchors = [(0.5, 0), (0.5, 1)]
+                else:
+                    anchors = [(0, 0.5), (1, 0.5)]
+            
+        self.anchors = anchors
+        TextItem.__init__(self, **kwds)
+        self.setParentItem(line)
+        self.valueChanged()
+
+    def valueChanged(self):
+        if not self.isVisible():
+            return
+        value = self.line.value()
+        self.setText(self.format.format(value=value))
+        self.updatePosition()
+
+    def getEndpoints(self):
+        # calculate points where line intersects view box
+        # (in line coordinates)
+        if self._endpoints[0] is None:
+            lr = self.line.boundingRect()
+            pt1 = Point(lr.left(), 0)
+            pt2 = Point(lr.right(), 0)
+            
+            if self.line.angle % 90 != 0:
+                # more expensive to find text position for oblique lines.
+                view = self.getViewBox()
+                if not self.isVisible() or not isinstance(view, ViewBox):
+                    # not in a viewbox, skip update
+                    return (None, None)
+                p = QtGui.QPainterPath()
+                p.moveTo(pt1)
+                p.lineTo(pt2)
+                p = self.line.itemTransform(view)[0].map(p)
+                vr = QtGui.QPainterPath()
+                vr.addRect(view.boundingRect())
+                paths = vr.intersected(p).toSubpathPolygons(QtGui.QTransform())
+                if len(paths) > 0:
+                    l = list(paths[0])
+                    pt1 = self.line.mapFromItem(view, l[0])
+                    pt2 = self.line.mapFromItem(view, l[1])
+            self._endpoints = (pt1, pt2)
+        return self._endpoints
+    
+    def updatePosition(self):
+        # update text position to relative view location along line
+        self._endpoints = (None, None)
+        pt1, pt2 = self.getEndpoints()
+        if pt1 is None:
+            return
+        pt = pt2 * self.orthoPos + pt1 * (1-self.orthoPos)
+        self.setPos(pt)
+        
+        # update anchor to keep text visible as it nears the view box edge
+        vr = self.line.viewRect()
+        if vr is not None:
+            self.setAnchor(self.anchors[0 if vr.center().y() < 0 else 1])
+        
+    def setVisible(self, v):
+        TextItem.setVisible(self, v)
+        if v:
+            self.updateText()
+            self.updatePosition()
+            
+    def setMovable(self, m):
+        """Set whether this label is movable by dragging along the line.
+        """
+        self.movable = m
+        self.setAcceptHoverEvents(m)
+        
+    def setPosition(self, p):
+        """Set the relative position (0.0-1.0) of this label within the view box
+        and along the line. 
+        
+        For horizontal (angle=0) and vertical (angle=90) lines, a value of 0.0
+        places the text at the bottom or left of the view, respectively. 
+        """
+        self.orthoPos = p
+        self.updatePosition()
+        
+    def setFormat(self, text):
+        """Set the text format string for this label.
+        
+        May optionally contain "{value}" to include the lines current value
+        (the text will be reformatted whenever the line is moved).
+        """
+        self.format = format
+        self.valueChanged()
+        
+    def mouseDragEvent(self, ev):
+        if self.movable and ev.button() == QtCore.Qt.LeftButton:
+            if ev.isStart():
+                self._moving = True
+                self._cursorOffset = self._posToRel(ev.buttonDownPos())
+                self._startPosition = self.orthoPos
+            ev.accept()
+
+            if not self._moving:
+                return
+
+            rel = self._posToRel(ev.pos())
+            self.orthoPos = np.clip(self._startPosition + rel - self._cursorOffset, 0, 1)
+            self.updatePosition()
+            if ev.isFinish():
+                self._moving = False
+
+    def mouseClickEvent(self, ev):
+        if self.moving and ev.button() == QtCore.Qt.RightButton:
+            ev.accept()
+            self.orthoPos = self._startPosition
+            self.moving = False
+
+    def hoverEvent(self, ev):
+        if not ev.isExit() and self.movable:
+            ev.acceptDrags(QtCore.Qt.LeftButton)
+
+    def viewTransformChanged(self):
+        self.updatePosition()
+        TextItem.viewTransformChanged(self)
+
+    def _posToRel(self, pos):
+        # convert local position to relative position along line between view bounds
+        pt1, pt2 = self.getEndpoints()
+        if pt1 is None:
+            return 0
+        view = self.getViewBox()
+        pos = self.mapToParent(pos)
+        return (pos.x() - pt1.x()) / (pt2.x()-pt1.x())

pyqtgraph/graphicsItems/ScatterPlotItem.py

@@ -19,17 +19,28 @@ __all__ = ['ScatterPlotItem', 'SpotItem']
 
 
 ## Build all symbol paths
-Symbols = OrderedDict([(name, QtGui.QPainterPath()) for name in ['o', 's', 't', 'd', '+', 'x']])
+Symbols = OrderedDict([(name, QtGui.QPainterPath()) for name in ['o', 's', 't', 't1', 't2', 't3','d', '+', 'x', 'p', 'h', 'star']])
 Symbols['o'].addEllipse(QtCore.QRectF(-0.5, -0.5, 1, 1))
 Symbols['s'].addRect(QtCore.QRectF(-0.5, -0.5, 1, 1))
 coords = {
     't': [(-0.5, -0.5), (0, 0.5), (0.5, -0.5)],
+    't1': [(-0.5, 0.5), (0, -0.5), (0.5, 0.5)],
+    't2': [(-0.5, -0.5), (-0.5, 0.5), (0.5, 0)],
+    't3': [(0.5, 0.5), (0.5, -0.5), (-0.5, 0)],
     'd': [(0., -0.5), (-0.4, 0.), (0, 0.5), (0.4, 0)],
     '+': [
         (-0.5, -0.05), (-0.5, 0.05), (-0.05, 0.05), (-0.05, 0.5),
         (0.05, 0.5), (0.05, 0.05), (0.5, 0.05), (0.5, -0.05),
         (0.05, -0.05), (0.05, -0.5), (-0.05, -0.5), (-0.05, -0.05)
     ],
+    'p': [(0, -0.5), (-0.4755, -0.1545), (-0.2939, 0.4045),
+          (0.2939, 0.4045), (0.4755, -0.1545)],
+    'h': [(0.433, 0.25), (0., 0.5), (-0.433, 0.25), (-0.433, -0.25),
+          (0, -0.5), (0.433, -0.25)],
+    'star': [(0, -0.5), (-0.1123, -0.1545), (-0.4755, -0.1545),
+             (-0.1816, 0.059), (-0.2939, 0.4045), (0, 0.1910),
+             (0.2939, 0.4045), (0.1816, 0.059), (0.4755, -0.1545),
+             (0.1123, -0.1545)]
 }
 for k, c in coords.items():
     Symbols[k].moveTo(*c[0])

pyqtgraph/graphicsItems/TextItem.py

@@ -1,13 +1,16 @@
+import numpy as np
 from ..Qt import QtCore, QtGui
 from ..Point import Point
-from .UIGraphicsItem import *
 from .. import functions as fn
+from .GraphicsObject import GraphicsObject
 
-class TextItem(UIGraphicsItem):
+
+class TextItem(GraphicsObject):
     """
     GraphicsItem displaying unscaled text (the text will always appear normal even inside a scaled ViewBox). 
     """
-    def __init__(self, text='', color=(200,200,200), html=None, anchor=(0,0), border=None, fill=None, angle=0):
+    def __init__(self, text='', color=(200,200,200), html=None, anchor=(0,0),
+                 border=None, fill=None, angle=0, rotateAxis=None):
         """
         ==============  =================================================================================
         **Arguments:**
@@ -20,19 +23,31 @@ class TextItem(UIGraphicsItem):
                         sets the lower-right corner.
         *border*        A pen to use when drawing the border
         *fill*          A brush to use when filling within the border
+        *angle*         Angle in degrees to rotate text. Default is 0; text will be displayed upright.
+        *rotateAxis*    If None, then a text angle of 0 always points along the +x axis of the scene.
+                        If a QPointF or (x,y) sequence is given, then it represents a vector direction
+                        in the parent's coordinate system that the 0-degree line will be aligned to. This
+                        Allows text to follow both the position and orientation of its parent while still
+                        discarding any scale and shear factors.
         ==============  =================================================================================
+
+
+        The effects of the `rotateAxis` and `angle` arguments are added independently. So for example:
+
+        * rotateAxis=None, angle=0 -> normal horizontal text
+        * rotateAxis=None, angle=90 -> normal vertical text
+        * rotateAxis=(1, 0), angle=0 -> text aligned with x axis of its parent
+        * rotateAxis=(0, 1), angle=0 -> text aligned with y axis of its parent
+        * rotateAxis=(1, 0), angle=90 -> text orthogonal to x axis of its parent        
         """
                      
-        ## not working yet
-        #*angle*      Angle in degrees to rotate text (note that the rotation assigned in this item's 
-                     #transformation will be ignored)
-                     
         self.anchor = Point(anchor)
+        self.rotateAxis = None if rotateAxis is None else Point(rotateAxis)
         #self.angle = 0
-        UIGraphicsItem.__init__(self)
+        GraphicsObject.__init__(self)
         self.textItem = QtGui.QGraphicsTextItem()
         self.textItem.setParentItem(self)
-        self.lastTransform = None
+        self._lastTransform = None
         self._bounds = QtCore.QRectF()
         if html is None:
             self.setText(text, color)
@@ -40,8 +55,7 @@ class TextItem(UIGraphicsItem):
             self.setHtml(html)
         self.fill = fn.mkBrush(fill)
         self.border = fn.mkPen(border)
-        self.rotate(angle)
+        self.setAngle(angle)
-        self.setFlag(self.ItemIgnoresTransformations)  ## This is required to keep the text unscaled inside the viewport
 
     def setText(self, text, color=(200,200,200)):
         """
@@ -52,14 +66,7 @@ class TextItem(UIGraphicsItem):
         color = fn.mkColor(color)
         self.textItem.setDefaultTextColor(color)
         self.textItem.setPlainText(text)
-        self.updateText()
+        self.updateTextPos()
-        #html = '<span style="color: #%s; text-align: center;">%s</span>' % (color, text)
-        #self.setHtml(html)
-        
-    def updateAnchor(self):
-        pass
-        #self.resetTransform()
-        #self.translate(0, 20)
         
     def setPlainText(self, *args):
         """
@@ -68,7 +75,7 @@ class TextItem(UIGraphicsItem):
         See QtGui.QGraphicsTextItem.setPlainText().
         """
         self.textItem.setPlainText(*args)
-        self.updateText()
+        self.updateTextPos()
         
     def setHtml(self, *args):
         """
@@ -77,7 +84,7 @@ class TextItem(UIGraphicsItem):
         See QtGui.QGraphicsTextItem.setHtml().
         """
         self.textItem.setHtml(*args)
-        self.updateText()
+        self.updateTextPos()
         
     def setTextWidth(self, *args):
         """
@@ -89,7 +96,7 @@ class TextItem(UIGraphicsItem):
         See QtGui.QGraphicsTextItem.setTextWidth().
         """
         self.textItem.setTextWidth(*args)
-        self.updateText()
+        self.updateTextPos()
         
     def setFont(self, *args):
         """
@@ -98,50 +105,43 @@ class TextItem(UIGraphicsItem):
         See QtGui.QGraphicsTextItem.setFont().
         """
         self.textItem.setFont(*args)
-        self.updateText()
+        self.updateTextPos()
         
-    #def setAngle(self, angle):
+    def setAngle(self, angle):
-        #self.angle = angle
+        self.angle = angle
-        #self.updateText()
+        self.updateTransform()
         
+    def setAnchor(self, anchor):
+        self.anchor = Point(anchor)
+        self.updateTextPos()
         
-    def updateText(self):
+    def updateTextPos(self):
+        # update text position to obey anchor
+        r = self.textItem.boundingRect()
+        tl = self.textItem.mapToParent(r.topLeft())
+        br = self.textItem.mapToParent(r.bottomRight())
+        offset = (br - tl) * self.anchor
+        self.textItem.setPos(-offset)
         
-        ## Needed to maintain font size when rendering to image with increased resolution
+        ### Needed to maintain font size when rendering to image with increased resolution
-        self.textItem.resetTransform()
+        #self.textItem.resetTransform()
-        #self.textItem.rotate(self.angle)
+        ##self.textItem.rotate(self.angle)
-        if self._exportOpts is not False and 'resolutionScale' in self._exportOpts:
+        #if self._exportOpts is not False and 'resolutionScale' in self._exportOpts:
-            s = self._exportOpts['resolutionScale']
+            #s = self._exportOpts['resolutionScale']
-            self.textItem.scale(s, s)
+            #self.textItem.scale(s, s)
-        
-        #br = self.textItem.mapRectToParent(self.textItem.boundingRect())
-        self.textItem.setPos(0,0)
-        br = self.textItem.boundingRect()
-        apos = self.textItem.mapToParent(Point(br.width()*self.anchor.x(), br.height()*self.anchor.y()))
-        #print br, apos
-        self.textItem.setPos(-apos.x(), -apos.y())
-        
-    #def textBoundingRect(self):
-        ### return the bounds of the text box in device coordinates
-        #pos = self.mapToDevice(QtCore.QPointF(0,0))
-        #if pos is None:
-            #return None
-        #tbr = self.textItem.boundingRect()
-        #return QtCore.QRectF(pos.x() - tbr.width()*self.anchor.x(), pos.y() - tbr.height()*self.anchor.y(), tbr.width(), tbr.height())
-
-
-    def viewRangeChanged(self):
-        self.updateText()
         
     def boundingRect(self):
         return self.textItem.mapToParent(self.textItem.boundingRect()).boundingRect()
 
+    def viewTransformChanged(self):
+        # called whenever view transform has changed.
+        # Do this here to avoid double-updates when view changes.
+        self.updateTransform()
+        
     def paint(self, p, *args):
-        tr = p.transform()
+        # this is not ideal because it causes another update to be scheduled.
-        if self.lastTransform is not None:
+        # ideally, we would have a sceneTransformChanged event to react to..
-            if tr != self.lastTransform:
+        self.updateTransform()
-                self.viewRangeChanged()
-        self.lastTransform = tr
         
         if self.border.style() != QtCore.Qt.NoPen or self.fill.style() != QtCore.Qt.NoBrush:
             p.setPen(self.border)
@@ -149,4 +149,37 @@ class TextItem(UIGraphicsItem):
             p.setRenderHint(p.Antialiasing, True)
             p.drawPolygon(self.textItem.mapToParent(self.textItem.boundingRect()))
         
+    def updateTransform(self):
+        # update transform such that this item has the correct orientation
+        # and scaling relative to the scene, but inherits its position from its
+        # parent.
+        # This is similar to setting ItemIgnoresTransformations = True, but 
+        # does not break mouse interaction and collision detection.
+        p = self.parentItem()
+        if p is None:
+            pt = QtGui.QTransform()
+        else:
+            pt = p.sceneTransform()
+        
+        if pt == self._lastTransform:
+            return
+
+        t = pt.inverted()[0]
+        # reset translation
+        t.setMatrix(t.m11(), t.m12(), t.m13(), t.m21(), t.m22(), t.m23(), 0, 0, t.m33())
+        
+        # apply rotation
+        angle = -self.angle
+        if self.rotateAxis is not None:
+            d = pt.map(self.rotateAxis) - pt.map(Point(0, 0))
+            a = np.arctan2(d.y(), d.x()) * 180 / np.pi
+            angle += a
+        t.rotate(angle)
+        
+        self.setTransform(t)
+        
+        self._lastTransform = pt
+        
+        self.updateTextPos()
+
         

pyqtgraph/graphicsItems/tests/test_InfiniteLine.py

@@ -0,0 +1,96 @@
+import pyqtgraph as pg
+from pyqtgraph.Qt import QtGui, QtCore, QtTest
+from pyqtgraph.tests import mouseDrag, mouseMove
+pg.mkQApp()
+
+
+def test_InfiniteLine():
+    # Test basic InfiniteLine API
+    plt = pg.plot()
+    plt.setXRange(-10, 10)
+    plt.setYRange(-10, 10)
+    plt.resize(600, 600)
+    
+    # seemingly arbitrary requirements; might need longer wait time for some platforms..
+    QtTest.QTest.qWaitForWindowShown(plt)
+    QtTest.QTest.qWait(100)
+    
+    vline = plt.addLine(x=1)
+    assert vline.angle == 90
+    br = vline.mapToView(QtGui.QPolygonF(vline.boundingRect()))
+    assert br.containsPoint(pg.Point(1, 5), QtCore.Qt.OddEvenFill)
+    assert not br.containsPoint(pg.Point(5, 0), QtCore.Qt.OddEvenFill)
+    hline = plt.addLine(y=0)
+    assert hline.angle == 0
+    assert hline.boundingRect().contains(pg.Point(5, 0))
+    assert not hline.boundingRect().contains(pg.Point(0, 5))
+
+    vline.setValue(2)
+    assert vline.value() == 2
+    vline.setPos(pg.Point(4, -5))
+    assert vline.value() == 4
+    
+    oline = pg.InfiniteLine(angle=30)
+    plt.addItem(oline)
+    oline.setPos(pg.Point(1, -1))
+    assert oline.angle == 30
+    assert oline.pos() == pg.Point(1, -1)
+    assert oline.value() == [1, -1]
+    
+    # test bounding rect for oblique line
+    br = oline.mapToScene(oline.boundingRect())
+    pos = oline.mapToScene(pg.Point(2, 0))
+    assert br.containsPoint(pos, QtCore.Qt.OddEvenFill)
+    px = pg.Point(-0.5, -1.0 / 3**0.5)
+    assert br.containsPoint(pos + 5 * px, QtCore.Qt.OddEvenFill)
+    assert not br.containsPoint(pos + 7 * px, QtCore.Qt.OddEvenFill)
+    
+
+def test_mouseInteraction():
+    plt = pg.plot()
+    plt.scene().minDragTime = 0  # let us simulate mouse drags very quickly.
+    vline = plt.addLine(x=0, movable=True)
+    plt.addItem(vline)
+    hline = plt.addLine(y=0, movable=True)
+    hline2 = plt.addLine(y=-1, movable=False)
+    plt.setXRange(-10, 10)
+    plt.setYRange(-10, 10)
+    
+    # test horizontal drag
+    pos = plt.plotItem.vb.mapViewToScene(pg.Point(0,5)).toPoint()
+    pos2 = pos - QtCore.QPoint(200, 200)
+    mouseMove(plt, pos)
+    assert vline.mouseHovering is True and hline.mouseHovering is False
+    mouseDrag(plt, pos, pos2, QtCore.Qt.LeftButton)
+    px = vline.pixelLength(pg.Point(1, 0), ortho=True)
+    assert abs(vline.value() - plt.plotItem.vb.mapSceneToView(pos2).x()) <= px
+
+    # test missed drag
+    pos = plt.plotItem.vb.mapViewToScene(pg.Point(5,0)).toPoint()
+    pos = pos + QtCore.QPoint(0, 6)
+    pos2 = pos + QtCore.QPoint(-20, -20)
+    mouseMove(plt, pos)
+    assert vline.mouseHovering is False and hline.mouseHovering is False
+    mouseDrag(plt, pos, pos2, QtCore.Qt.LeftButton)
+    assert hline.value() == 0
+
+    # test vertical drag
+    pos = plt.plotItem.vb.mapViewToScene(pg.Point(5,0)).toPoint()
+    pos2 = pos - QtCore.QPoint(50, 50)
+    mouseMove(plt, pos)
+    assert vline.mouseHovering is False and hline.mouseHovering is True
+    mouseDrag(plt, pos, pos2, QtCore.Qt.LeftButton)
+    px = hline.pixelLength(pg.Point(1, 0), ortho=True)
+    assert abs(hline.value() - plt.plotItem.vb.mapSceneToView(pos2).y()) <= px
+
+    # test non-interactive line
+    pos = plt.plotItem.vb.mapViewToScene(pg.Point(5,-1)).toPoint()
+    pos2 = pos - QtCore.QPoint(50, 50)
+    mouseMove(plt, pos)
+    assert hline2.mouseHovering == False
+    mouseDrag(plt, pos, pos2, QtCore.Qt.LeftButton)
+    assert hline2.value() == -1
+
+
+if __name__ == '__main__':
+    test_mouseInteraction()

pyqtgraph/tests/__init__.py

@@ -1 +1,2 @@
 from .image_testing import assertImageApproved
+from .ui_testing import mousePress, mouseMove, mouseRelease, mouseDrag, mouseClick

pyqtgraph/tests/ui_testing.py

@@ -0,0 +1,55 @@
+
+# Functions for generating user input events. 
+# We would like to use QTest for this purpose, but it seems to be broken.
+# See: http://stackoverflow.com/questions/16299779/qt-qgraphicsview-unit-testing-how-to-keep-the-mouse-in-a-pressed-state
+
+from ..Qt import QtCore, QtGui, QT_LIB
+
+
+def mousePress(widget, pos, button, modifier=None):
+    if isinstance(widget, QtGui.QGraphicsView):
+        widget = widget.viewport()
+    if modifier is None:
+        modifier = QtCore.Qt.NoModifier
+    if QT_LIB != 'PyQt5' and isinstance(pos, QtCore.QPointF):
+        pos = pos.toPoint()
+    event = QtGui.QMouseEvent(QtCore.QEvent.MouseButtonPress, pos, button, QtCore.Qt.NoButton, modifier)
+    QtGui.QApplication.sendEvent(widget, event)
+
+
+def mouseRelease(widget, pos, button, modifier=None):
+    if isinstance(widget, QtGui.QGraphicsView):
+        widget = widget.viewport()
+    if modifier is None:
+        modifier = QtCore.Qt.NoModifier
+    if QT_LIB != 'PyQt5' and isinstance(pos, QtCore.QPointF):
+        pos = pos.toPoint()
+    event = QtGui.QMouseEvent(QtCore.QEvent.MouseButtonRelease, pos, button, QtCore.Qt.NoButton, modifier)
+    QtGui.QApplication.sendEvent(widget, event)
+
+
+def mouseMove(widget, pos, buttons=None, modifier=None):
+    if isinstance(widget, QtGui.QGraphicsView):
+        widget = widget.viewport()
+    if modifier is None:
+        modifier = QtCore.Qt.NoModifier
+    if buttons is None:
+        buttons = QtCore.Qt.NoButton
+    if QT_LIB != 'PyQt5' and isinstance(pos, QtCore.QPointF):
+        pos = pos.toPoint()
+    event = QtGui.QMouseEvent(QtCore.QEvent.MouseMove, pos, QtCore.Qt.NoButton, buttons, modifier)
+    QtGui.QApplication.sendEvent(widget, event)
+
+
+def mouseDrag(widget, pos1, pos2, button, modifier=None):
+    mouseMove(widget, pos1)
+    mousePress(widget, pos1, button, modifier)
+    mouseMove(widget, pos2, button, modifier)
+    mouseRelease(widget, pos2, button, modifier)
+
+    
+def mouseClick(widget, pos, button, modifier=None):
+    mouseMove(widget, pos)
+    mousePress(widget, pos, button, modifier)
+    mouseRelease(widget, pos, button, modifier)
+