Merge pull request #623 from termim/ScatterPlot

Scatter plot

examples/ScatterPlot.py

@@ -11,6 +11,7 @@ import initExample
 from pyqtgraph.Qt import QtGui, QtCore
 import pyqtgraph as pg
 import numpy as np
+from collections import namedtuple
 
 app = QtGui.QApplication([])
 mw = QtGui.QMainWindow()
@@ -32,8 +33,8 @@ print("Generating data, this takes a few seconds...")
 ## There are a few different ways we can draw scatter plots; each is optimized for different types of data:
 
 
-## 1) All spots identical and transform-invariant (top-left plot). 
+## 1) All spots identical and transform-invariant (top-left plot).
-## In this case we can get a huge performance boost by pre-rendering the spot 
+## In this case we can get a huge performance boost by pre-rendering the spot
 ## image and just drawing that image repeatedly.
 
 n = 300
@@ -57,21 +58,41 @@ s1.sigClicked.connect(clicked)
 
 
 
-## 2) Spots are transform-invariant, but not identical (top-right plot). 
+## 2) Spots are transform-invariant, but not identical (top-right plot).
-## In this case, drawing is almsot as fast as 1), but there is more startup 
+## In this case, drawing is almsot as fast as 1), but there is more startup
-## overhead and memory usage since each spot generates its own pre-rendered 
+## overhead and memory usage since each spot generates its own pre-rendered
 ## image.
 
+TextSymbol = namedtuple("TextSymbol", "label symbol scale")
+
+def createLabel(label, angle):
+    symbol = QtGui.QPainterPath()
+    #symbol.addText(0, 0, QFont("San Serif", 10), label)
+    f = QtGui.QFont()
+    f.setPointSize(10)
+    symbol.addText(0, 0, f, label)
+    br = symbol.boundingRect()
+    scale = min(1. / br.width(), 1. / br.height())
+    tr = QtGui.QTransform()
+    tr.scale(scale, scale)
+    tr.rotate(angle)
+    tr.translate(-br.x() - br.width()/2., -br.y() - br.height()/2.)
+    return TextSymbol(label, tr.map(symbol), 0.1 / scale)
+
+random_str = lambda : (''.join([chr(np.random.randint(ord('A'),ord('z'))) for i in range(np.random.randint(1,5))]), np.random.randint(0, 360))
+
 s2 = pg.ScatterPlotItem(size=10, pen=pg.mkPen('w'), pxMode=True)
 pos = np.random.normal(size=(2,n), scale=1e-5)
 spots = [{'pos': pos[:,i], 'data': 1, 'brush':pg.intColor(i, n), 'symbol': i%5, 'size': 5+i/10.} for i in range(n)]
 s2.addPoints(spots)
+spots = [{'pos': pos[:,i], 'data': 1, 'brush':pg.intColor(i, n), 'symbol': label[1], 'size': label[2]*(5+i/10.)} for (i, label) in [(i, createLabel(*random_str())) for i in range(n)]]
+s2.addPoints(spots)
 w2.addItem(s2)
 s2.sigClicked.connect(clicked)
 
 
-## 3) Spots are not transform-invariant, not identical (bottom-left). 
+## 3) Spots are not transform-invariant, not identical (bottom-left).
-## This is the slowest case, since all spots must be completely re-drawn 
+## This is the slowest case, since all spots must be completely re-drawn
 ## every time because their apparent transformation may have changed.
 
 s3 = pg.ScatterPlotItem(pxMode=False)   ## Set pxMode=False to allow spots to transform with the view

pyqtgraph/graphicsItems/ScatterPlotItem.py

@@ -126,7 +126,7 @@ class SymbolAtlas(object):
         keyi = None
         sourceRecti = None
         for i, rec in enumerate(opts):
-            key = (rec[3], rec[2], id(rec[4]), id(rec[5]))   # TODO: use string indexes?
+            key = (id(rec[3]), rec[2], id(rec[4]), id(rec[5]))   # TODO: use string indexes?
             if key == keyi:
                 sourceRect[i] = sourceRecti
             else:
@@ -136,6 +136,7 @@ class SymbolAtlas(object):
                     newRectSrc = QtCore.QRectF()
                     newRectSrc.pen = rec['pen']
                     newRectSrc.brush = rec['brush']
+                    newRectSrc.symbol = rec[3]
                     self.symbolMap[key] = newRectSrc
                     self.atlasValid = False
                     sourceRect[i] = newRectSrc
@@ -151,7 +152,7 @@ class SymbolAtlas(object):
         images = []
         for key, sourceRect in self.symbolMap.items():
             if sourceRect.width() == 0:
-                img = renderSymbol(key[0], key[1], sourceRect.pen, sourceRect.brush)
+                img = renderSymbol(sourceRect.symbol, key[1], sourceRect.pen, sourceRect.brush)
                 images.append(img)  ## we only need this to prevent the images being garbage collected immediately
                 arr = fn.imageToArray(img, copy=False, transpose=False)
             else:

pyqtgraph/graphicsItems/tests/test_ScatterPlotItem.py

@@ -1,3 +1,4 @@
+from pyqtgraph.Qt import QtGui, QtCore
 import pyqtgraph as pg
 import numpy as np
 app = pg.mkQApp()
@@ -7,9 +8,16 @@ app.processEvents()
 
 def test_scatterplotitem():
     plot = pg.PlotWidget()
-    # set view range equal to its bounding rect. 
+    # set view range equal to its bounding rect.
     # This causes plots to look the same regardless of pxMode.
     plot.setRange(rect=plot.boundingRect())
+
+    # test SymbolAtlas accepts custom symbol
+    s = pg.ScatterPlotItem()
+    symbol = QtGui.QPainterPath()
+    symbol.addEllipse(QtCore.QRectF(-0.5, -0.5, 1, 1))
+    s.addPoints([{'pos': [0,0], 'data': 1, 'symbol': symbol}])
+
     for i, pxMode in enumerate([True, False]):
         for j, useCache in enumerate([True, False]):
             s = pg.ScatterPlotItem()
@@ -17,14 +25,14 @@ def test_scatterplotitem():
             plot.addItem(s)
             s.setData(x=np.array([10,40,20,30])+i*100, y=np.array([40,60,10,30])+j*100, pxMode=pxMode)
             s.addPoints(x=np.array([60, 70])+i*100, y=np.array([60, 70])+j*100, size=[20, 30])
-            
+
             # Test uniform spot updates
             s.setSize(10)
             s.setBrush('r')
             s.setPen('g')
             s.setSymbol('+')
             app.processEvents()
-            
+
             # Test list spot updates
             s.setSize([10] * 6)
             s.setBrush([pg.mkBrush('r')] * 6)
@@ -55,7 +63,7 @@ def test_scatterplotitem():
 
 def test_init_spots():
     plot = pg.PlotWidget()
-    # set view range equal to its bounding rect. 
+    # set view range equal to its bounding rect.
     # This causes plots to look the same regardless of pxMode.
     plot.setRange(rect=plot.boundingRect())
     spots = [
@@ -63,28 +71,28 @@ def test_init_spots():
         {'pos': (1, 2), 'pen': None, 'brush': None, 'data': 'zzz'},
     ]
     s = pg.ScatterPlotItem(spots=spots)
-    
+
     # Check we can display without errors
     plot.addItem(s)
     app.processEvents()
     plot.clear()
-    
+
     # check data is correct
     spots = s.points()
-    
+
     defPen = pg.mkPen(pg.getConfigOption('foreground'))
 
     assert spots[0].pos().x() == 0
     assert spots[0].pos().y() == 1
     assert spots[0].pen() == defPen
     assert spots[0].data() is None
-    
+
     assert spots[1].pos().x() == 1
     assert spots[1].pos().y() == 2
     assert spots[1].pen() == pg.mkPen(None)
     assert spots[1].brush() == pg.mkBrush(None)
     assert spots[1].data() == 'zzz'
-    
+
 
 if __name__ == '__main__':
     test_scatterplotitem()