Source code for pyqtgraph.graphicsItems.GridItem

from ..Qt import QtGui, QtCore
from .UIGraphicsItem import *
import numpy as np
from ..Point import Point
from .. import functions as fn

__all__ = ['GridItem']
[docs]class GridItem(UIGraphicsItem): """ **Bases:** :class:`UIGraphicsItem <pyqtgraph.UIGraphicsItem>` Displays a rectangular grid of lines indicating major divisions within a coordinate system. Automatically determines what divisions to use. """
[docs] def __init__(self): UIGraphicsItem.__init__(self) #QtGui.QGraphicsItem.__init__(self, *args) #self.setFlag(QtGui.QGraphicsItem.ItemClipsToShape) #self.setCacheMode(QtGui.QGraphicsItem.DeviceCoordinateCache) self.picture = None
def viewRangeChanged(self): UIGraphicsItem.viewRangeChanged(self) self.picture = None #UIGraphicsItem.viewRangeChanged(self) #self.update() def paint(self, p, opt, widget): #p.setPen(QtGui.QPen(QtGui.QColor(100, 100, 100))) #p.drawRect(self.boundingRect()) #UIGraphicsItem.paint(self, p, opt, widget) ### draw picture if self.picture is None: #print "no pic, draw.." self.generatePicture() p.drawPicture(QtCore.QPointF(0, 0), self.picture) #p.setPen(QtGui.QPen(QtGui.QColor(255,0,0))) #p.drawLine(0, -100, 0, 100) #p.drawLine(-100, 0, 100, 0) #print "drawing Grid." def generatePicture(self): self.picture = QtGui.QPicture() p = QtGui.QPainter() p.begin(self.picture) dt = fn.invertQTransform(self.viewTransform()) vr = self.getViewWidget().rect() unit = self.pixelWidth(), self.pixelHeight() dim = [vr.width(), vr.height()] lvr = self.boundingRect() ul = np.array([lvr.left(), lvr.top()]) br = np.array([lvr.right(), lvr.bottom()]) texts = [] if ul[1] > br[1]: x = ul[1] ul[1] = br[1] br[1] = x for i in [2,1,0]: ## Draw three different scales of grid dist = br-ul nlTarget = 10.**i d = 10. ** np.floor(np.log10(abs(dist/nlTarget))+0.5) ul1 = np.floor(ul / d) * d br1 = np.ceil(br / d) * d dist = br1-ul1 nl = (dist / d) + 0.5 #print "level", i #print " dim", dim #print " dist", dist #print " d", d #print " nl", nl for ax in range(0,2): ## Draw grid for both axes ppl = dim[ax] / nl[ax] c = np.clip(3.*(ppl-3), 0., 30.) linePen = QtGui.QPen(QtGui.QColor(255, 255, 255, c)) textPen = QtGui.QPen(QtGui.QColor(255, 255, 255, c*2)) #linePen.setCosmetic(True) #linePen.setWidth(1) bx = (ax+1) % 2 for x in range(0, int(nl[ax])): linePen.setCosmetic(False) if ax == 0: linePen.setWidthF(self.pixelWidth()) #print "ax 0 height", self.pixelHeight() else: linePen.setWidthF(self.pixelHeight()) #print "ax 1 width", self.pixelWidth() p.setPen(linePen) p1 = np.array([0.,0.]) p2 = np.array([0.,0.]) p1[ax] = ul1[ax] + x * d[ax] p2[ax] = p1[ax] p1[bx] = ul[bx] p2[bx] = br[bx] ## don't draw lines that are out of bounds. if p1[ax] < min(ul[ax], br[ax]) or p1[ax] > max(ul[ax], br[ax]): continue p.drawLine(QtCore.QPointF(p1[0], p1[1]), QtCore.QPointF(p2[0], p2[1])) if i < 2: p.setPen(textPen) if ax == 0: x = p1[0] + unit[0] y = ul[1] + unit[1] * 8. else: x = ul[0] + unit[0]*3 y = p1[1] + unit[1] texts.append((QtCore.QPointF(x, y), "%g"%p1[ax])) tr = self.deviceTransform() #tr.scale(1.5, 1.5) p.setWorldTransform(fn.invertQTransform(tr)) for t in texts: x = tr.map(t[0]) + Point(0.5, 0.5) p.drawText(x, t[1]) p.end()