from __future__ import division
from ..Qt import QtGui, QtCore
import numpy as np
from .. import functions as fn
from .. import debug as debug
from .GraphicsObject import GraphicsObject
from ..Point import Point
from .. import getConfigOption
from .GradientEditorItem import Gradients # List of colormaps
from ..colormap import ColorMap
try:
from collections.abc import Callable
except ImportError:
# fallback for python < 3.3
from collections import Callable
__all__ = ['PColorMeshItem']
[docs]class PColorMeshItem(GraphicsObject):
"""
**Bases:** :class:`GraphicsObject <pyqtgraph.GraphicsObject>`
"""
[docs] def __init__(self, *args, **kwargs):
"""
Create a pseudocolor plot with convex polygons.
Call signature:
``PColorMeshItem([x, y,] z, **kwargs)``
x and y can be used to specify the corners of the quadrilaterals.
z must be used to specified to color of the quadrilaterals.
Parameters
----------
x, y : np.ndarray, optional, default None
2D array containing the coordinates of the polygons
z : np.ndarray
2D array containing the value which will be maped into the polygons
colors.
If x and y is None, the polygons will be displaced on a grid
otherwise x and y will be used as polygons vertices coordinates as::
(x[i+1, j], y[i+1, j]) (x[i+1, j+1], y[i+1, j+1])
+---------+
| z[i, j] |
+---------+
(x[i, j], y[i, j]) (x[i, j+1], y[i, j+1])
"ASCII from: <https://matplotlib.org/3.2.1/api/_as_gen/
matplotlib.pyplot.pcolormesh.html>".
cmap : str, default 'viridis
Colormap used to map the z value to colors.
edgecolors : dict, default None
The color of the edges of the polygons.
Default None means no edges.
The dict may contains any arguments accepted by :func:`mkColor() <pyqtgraph.mkColor>`.
Example:
``mkPen(color='w', width=2)``
antialiasing : bool, default False
Whether to draw edgelines with antialiasing.
Note that if edgecolors is None, antialiasing is always False.
"""
GraphicsObject.__init__(self)
self.qpicture = None ## rendered picture for display
self.axisOrder = getConfigOption('imageAxisOrder')
if 'edgecolors' in kwargs.keys():
self.edgecolors = kwargs['edgecolors']
else:
self.edgecolors = None
if 'antialiasing' in kwargs.keys():
self.antialiasing = kwargs['antialiasing']
else:
self.antialiasing = False
if 'cmap' in kwargs.keys():
if kwargs['cmap'] in Gradients.keys():
self.cmap = kwargs['cmap']
else:
raise NameError('Undefined colormap, should be one of the following: '+', '.join(['"'+i+'"' for i in Gradients.keys()])+'.')
else:
self.cmap = 'viridis'
# If some data have been sent we directly display it
if len(args)>0:
self.setData(*args)
def _prepareData(self, args):
"""
Check the shape of the data.
Return a set of 2d array x, y, z ready to be used to draw the picture.
"""
# User didn't specified data
if len(args)==0:
self.x = None
self.y = None
self.z = None
# User only specified z
elif len(args)==1:
# If x and y is None, the polygons will be displaced on a grid
x = np.arange(0, args[0].shape[0]+1, 1)
y = np.arange(0, args[0].shape[1]+1, 1)
self.x, self.y = np.meshgrid(x, y, indexing='ij')
self.z = args[0]
# User specified x, y, z
elif len(args)==3:
# Shape checking
if args[0].shape[0] != args[2].shape[0]+1 or args[0].shape[1] != args[2].shape[1]+1:
raise ValueError('The dimension of x should be one greater than the one of z')
if args[1].shape[0] != args[2].shape[0]+1 or args[1].shape[1] != args[2].shape[1]+1:
raise ValueError('The dimension of y should be one greater than the one of z')
self.x = args[0]
self.y = args[1]
self.z = args[2]
else:
ValueError('Data must been sent as (z) or (x, y, z)')
[docs] def setData(self, *args):
"""
Set the data to be drawn.
Parameters
----------
x, y : np.ndarray, optional, default None
2D array containing the coordinates of the polygons
z : np.ndarray
2D array containing the value which will be maped into the polygons
colors.
If x and y is None, the polygons will be displaced on a grid
otherwise x and y will be used as polygons vertices coordinates as::
(x[i+1, j], y[i+1, j]) (x[i+1, j+1], y[i+1, j+1])
+---------+
| z[i, j] |
+---------+
(x[i, j], y[i, j]) (x[i, j+1], y[i, j+1])
"ASCII from: <https://matplotlib.org/3.2.1/api/_as_gen/
matplotlib.pyplot.pcolormesh.html>".
"""
# Prepare data
cd = self._prepareData(args)
# Has the view bounds changed
shapeChanged = False
if self.qpicture is None:
shapeChanged = True
elif len(args)==1:
if args[0].shape[0] != self.x[:,1][-1] or args[0].shape[1] != self.y[0][-1]:
shapeChanged = True
elif len(args)==3:
if np.any(self.x != args[0]) or np.any(self.y != args[1]):
shapeChanged = True
self.qpicture = QtGui.QPicture()
p = QtGui.QPainter(self.qpicture)
# We set the pen of all polygons once
if self.edgecolors is None:
p.setPen(fn.mkPen(QtGui.QColor(0, 0, 0, 0)))
else:
p.setPen(fn.mkPen(self.edgecolors))
if self.antialiasing:
p.setRenderHint(QtGui.QPainter.RenderHint.Antialiasing)
## Prepare colormap
# First we get the LookupTable
pos = [i[0] for i in Gradients[self.cmap]['ticks']]
color = [i[1] for i in Gradients[self.cmap]['ticks']]
cmap = ColorMap(pos, color)
lut = cmap.getLookupTable(0.0, 1.0, 256)
# Second we associate each z value, that we normalize, to the lut
norm = self.z - self.z.min()
norm = norm/norm.max()
norm = (norm*(len(lut)-1)).astype(int)
# Go through all the data and draw the polygons accordingly
for xi in range(self.z.shape[0]):
for yi in range(self.z.shape[1]):
# Set the color of the polygon first
c = lut[norm[xi][yi]]
p.setBrush(fn.mkBrush(QtGui.QColor(c[0], c[1], c[2])))
polygon = QtGui.QPolygonF(
[QtCore.QPointF(self.x[xi][yi], self.y[xi][yi]),
QtCore.QPointF(self.x[xi+1][yi], self.y[xi+1][yi]),
QtCore.QPointF(self.x[xi+1][yi+1], self.y[xi+1][yi+1]),
QtCore.QPointF(self.x[xi][yi+1], self.y[xi][yi+1])]
)
# DrawConvexPlygon is faster
p.drawConvexPolygon(polygon)
p.end()
self.update()
self.prepareGeometryChange()
if shapeChanged:
self.informViewBoundsChanged()
def paint(self, p, *args):
if self.z is None:
return
p.drawPicture(0, 0, self.qpicture)
def setBorder(self, b):
self.border = fn.mkPen(b)
self.update()
def width(self):
if self.x is None:
return None
return np.max(self.x)
def height(self):
if self.y is None:
return None
return np.max(self.y)
def boundingRect(self):
if self.qpicture is None:
return QtCore.QRectF(0., 0., 0., 0.)
return QtCore.QRectF(self.qpicture.boundingRect())