1# -*- coding: utf-8 -*-
2"""
3This example demonstrates linearized ColorMap objects using colormap.makeMonochrome()
4or using the `ColorMap`'s `linearize()` method.
5"""
6# Add path to library (just for examples; you do not need this)
7import initExample
8
9import numpy as np
10from pyqtgraph.Qt import QtCore, QtGui
11import pyqtgraph as pg
12
13name_list = (
14    'warm','neutral','cool',
15    'green','amber','blue','red','pink','lavender',
16    (0.5, 0.2, 0.1, 0.8)
17)
18ramp_list = [
19    pg.colormap.makeMonochrome(name)
20    for name in name_list
21]
22
23cm_list = []
24# Create a gray ramp for demonstrating the idea:
25cm = pg.ColorMap( None, [
26    QtGui.QColor(  0,   0,   0),
27    QtGui.QColor( 10,  10,  10),
28    QtGui.QColor(127, 127, 127),
29    QtGui.QColor(240, 240, 240),
30    QtGui.QColor(255, 255, 255)
31])
32cm_list.append(('Distorted gray ramp',cm))
33
34# Create a rainbow scale in HSL color space:
35length = 41
36col_list = []
37for idx in range(length):
38    frac = idx/(length-1)
39    qcol = QtGui.QColor()
40    qcol.setHslF( (2*frac-0.15)%1.0, 0.8, 0.5-0.5*np.cos(np.pi*frac) )
41    col_list.append(qcol)
42cm = pg.ColorMap( None, col_list )
43cm_list.append( ('Distorted HSL spiral', cm) )
44
45# Create some random examples:
46for example_idx in range(3):
47    previous = None
48    col_list = []
49    for idx in range(8):
50        values = np.random.random((3))
51        if previous is not None:
52            intermediate = (values + previous) / 2
53            qcol = QtGui.QColor()
54            qcol.setRgbF( *intermediate )
55            col_list.append( qcol)
56        qcol1 = QtGui.QColor()
57        qcol1.setRgbF( *values )
58        col_list.append( qcol1)
59        previous = values
60    cm = pg.ColorMap( None, col_list )
61    cm_list.append( (f'random {example_idx+1}', cm) )
62
63app = pg.mkQApp()
64win = QtGui.QMainWindow()
65win.resize(1000,800)
66
67lw = pg.GraphicsLayoutWidget()
68lw.setFixedWidth(1000)
69lw.setSizePolicy(QtGui.QSizePolicy.Policy.Expanding, QtGui.QSizePolicy.Policy.Expanding)
70
71scr = QtGui.QScrollArea()
72scr.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarPolicy.ScrollBarAlwaysOn)
73scr.setWidget(lw)
74win.setCentralWidget(scr)
75win.setWindowTitle('pyqtgraph example: Linearized color maps')
76win.show()
77
78bar_width = 32
79bar_data = pg.colormap.modulatedBarData(width=bar_width)
80
81num_bars = 0
82
83def add_heading(lw, name):
84    global num_bars
85    lw.addLabel('=== '+name+' ===')
86    num_bars += 1
87    lw.nextRow()
88
89def add_bar(lw, name, cm):
90    global num_bars
91    lw.addLabel(name)
92    imi = pg.ImageItem( bar_data )
93    imi.setLookupTable( cm.getLookupTable(alpha=True) )
94    vb = lw.addViewBox(lockAspect=True, enableMouse=False)
95    vb.addItem( imi )
96    num_bars += 1
97    lw.nextRow()
98
99add_heading(lw, 'ramp generator')
100for cm in ramp_list:
101    add_bar(lw, cm.name, cm)
102
103add_heading(lw, 'linearizer demonstration')
104for (name, cm) in cm_list:
105    add_bar(lw, name, cm)
106    cm.linearize()
107    add_bar(lw, '> linearized', cm)
108
109add_heading(lw, 'consistency with included maps')
110for name in ('CET-C3', 'CET-L17', 'CET-L2'):
111    # lw.addLabel(str(name))
112    cm = pg.colormap.get(name)
113    add_bar(lw, name, cm)
114    cm.linearize()
115    add_bar(lw, '> linearized', cm)
116
117lw.setFixedHeight(num_bars * (bar_width+5) )
118
119if __name__ == '__main__':
120    pg.exec()
121