DAMASK_EICMD/python/damask/_colormap.py

604 lines
20 KiB
Python
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

import os
import json
import functools
import colorsys
import numpy as np
import matplotlib as mpl
if os.name == 'posix' and 'DISPLAY' not in os.environ:
mpl.use('Agg')
import matplotlib.pyplot as plt
from matplotlib import cm
from PIL import Image
from . import util
from . import Table
_eps = 216./24389.
_kappa = 24389./27.
_ref_white = np.array([.95047, 1.00000, 1.08883]) # Observer = 2, Illuminant = D65
# ToDo (if needed)
# - support alpha channel (paraview/ASCII/input)
# - support NaN color (paraview)
class Colormap(mpl.colors.ListedColormap):
"""
Enhance matplotlib colormap functionality to be used within DAMASK.
References
----------
K. Moreland, Proceedings of the 5th International Symposium on Advances in Visual Computing, 2009
https://doi.org/10.1007/978-3-642-10520-3_9
P. Eisenlohr et al., International Journal of Plasticity 46:3753, 2013
https://doi.org/10.1016/j.ijplas.2012.09.012
Matplotlib colormaps overview
https://matplotlib.org/tutorials/colors/colormaps.html
"""
def __add__(self,other):
"""Concatenate."""
return Colormap(np.vstack((self.colors,other.colors)),
f'{self.name}+{other.name}')
def __iadd__(self,other):
"""Concatenate (in-place)."""
return self.__add__(other)
def __invert__(self):
"""Reverse."""
return self.reversed()
def __repr__(self):
"""Show as matplotlib figure."""
fig = plt.figure(self.name,figsize=(5,.5))
ax1 = fig.add_axes([0, 0, 1, 1])
ax1.set_axis_off()
ax1.imshow(np.linspace(0,1,self.N).reshape(1,-1),
aspect='auto', cmap=self, interpolation='nearest')
plt.show(block = False)
return 'Colormap: '+self.name
@staticmethod
def from_range(low,high,name='DAMASK colormap',N=256,model='rgb'):
"""
Create a perceptually uniform colormap between given (inclusive) bounds.
Colors are internally stored as R(ed) G(green) B(lue) values.
The colormap can be used in matplotlib/seaborn or exported to
file for external use.
Parameters
----------
low : numpy.ndarray of shape (3)
Color definition for minimum value.
high : numpy.ndarray of shape (3)
Color definition for maximum value.
N : int, optional
The number of color quantization levels. Defaults to 256.
name : str, optional
The name of the colormap. Defaults to `DAMASK colormap`.
model : {'rgb', 'hsv', 'hsl', 'xyz', 'lab', 'msh'}
Colormodel used for input color definitions. Defaults to `rgb`.
The available color models are:
- 'rgb': R(ed) G(green) B(lue).
- 'hsv': H(ue) S(aturation) V(alue).
- 'hsl': H(ue) S(aturation) L(uminance).
- 'xyz': CIE Xyz.
- 'lab': CIE Lab.
- 'msh': Msh (for perceptual uniform interpolation).
Returns
-------
new : damask.Colormap
Colormap within given bounds.
Examples
--------
>>> import damask
>>> damask.Colormap.from_range((0,0,1),(0,0,0),'blue_to_black')
"""
low_high = np.vstack((low,high))
if model.lower() == 'rgb':
if np.any(low_high<0) or np.any(low_high>1):
raise ValueError(f'RGB color {low} | {high} are out of range.')
low_,high_ = map(Colormap._rgb2msh,low_high)
elif model.lower() == 'hsv':
if np.any(low_high<0) or np.any(low_high>[360,1,1]):
raise ValueError(f'HSV color {low} | {high} are out of range.')
low_,high_ = map(Colormap._hsv2msh,low_high)
elif model.lower() == 'hsl':
if np.any(low_high<0) or np.any(low_high>[360,1,1]):
raise ValueError(f'HSL color {low} | {high} are out of range.')
low_,high_ = map(Colormap._hsl2msh,low_high)
elif model.lower() == 'xyz':
low_,high_ = map(Colormap._xyz2msh,low_high)
elif model.lower() == 'lab':
if np.any(low_high[:,0]<0):
raise ValueError(f'CIE Lab color {low} | {high} are out of range.')
low_,high_ = map(Colormap._lab2msh,low_high)
elif model.lower() == 'msh':
low_,high_ = low_high[0],low_high[1]
else:
raise ValueError(f'Invalid color model: {model}.')
msh = map(functools.partial(Colormap._interpolate_msh,low=low_,high=high_),np.linspace(0,1,N))
rgb = np.array(list(map(Colormap._msh2rgb,msh)))
return Colormap(rgb,name=name)
@staticmethod
def from_predefined(name,N=256):
"""
Select from a set of predefined colormaps.
Predefined colormaps include native matplotlib colormaps
and common DAMASK colormaps.
Parameters
----------
name : str
The name of the colormap.
N : int, optional
The number of color quantization levels. Defaults to 256.
This parameter is not used for matplotlib colormaps
that are of type `ListedColormap`.
Returns
-------
new : damask.Colormap
Predefined colormap.
Examples
--------
>>> import damask
>>> damask.Colormap.from_predefined('strain')
"""
# matplotlib presets
try:
colormap = cm.__dict__[name]
return Colormap(np.array(list(map(colormap,np.linspace(0,1,N)))
if isinstance(colormap,mpl.colors.LinearSegmentedColormap) else
colormap.colors),
name=name)
except KeyError:
# DAMASK presets
definition = Colormap._predefined_DAMASK[name]
return Colormap.from_range(definition['low'],definition['high'],name,N)
def shade(self,field,bounds=None,gap=None):
"""
Generate PIL image of 2D field using colormap.
Parameters
----------
field : numpy.array of shape (:,:)
Data to be shaded.
bounds : iterable of len (2), optional
Colormap value range (low,high).
gap : field.dtype, optional
Transparent value. NaN will always be rendered transparent.
Returns
-------
PIL.Image
RGBA image of shaded data.
"""
N = len(self.colors)
mask = np.logical_not(np.isnan(field) if gap is None else \
np.logical_or (np.isnan(field), field == gap)) # mask NaN (and gap if present)
lo,hi = (field[mask].min(),field[mask].max()) if bounds is None else \
(min(bounds[:2]),max(bounds[:2]))
delta,avg = hi-lo,0.5*(hi+lo)
if delta * 1e8 <= avg: # delta is similar to numerical noise
hi,lo = hi+0.5*avg,lo-0.5*avg # extend range to have actual data centered within
return Image.fromarray(
(np.dstack((
self.colors[(np.round(np.clip((field-lo)/(hi-lo),0.0,1.0)*(N-1))).astype(np.uint16),:3],
mask.astype(float)
)
)*255
).astype(np.uint8),
mode='RGBA')
def reversed(self,name=None):
"""
Reverse.
Parameters
----------
name : str, optional
The name for the reversed colormap.
A name of None will be replaced by the name of the parent colormap + "_r".
Returns
-------
damask.Colormap
The reversed colormap.
Examples
--------
>>> import damask
>>> damask.Colormap.from_predefined('stress').reversed()
"""
rev = super(Colormap,self).reversed(name)
return Colormap(np.array(rev.colors),rev.name[:-4] if rev.name.endswith('_r_r') else rev.name)
def _get_file_handle(self,fname,extension):
"""
Provide file handle.
Parameters
----------
fname : file, str, pathlib.Path, or None
Filename or filehandle, will be name of the colormap+extension if None.
extension: str
Extension of the filename.
Returns
-------
f : file object
File handle with write access.
"""
if fname is None:
fhandle = open(self.name.replace(' ','_')+'.'+extension,'w',newline='\n')
else:
try:
fhandle = open(fname,'w',newline='\n')
except TypeError:
fhandle = fname
return fhandle
def save_paraview(self,fname=None):
"""
Save as JSON file for use in Paraview.
Parameters
----------
fname : file, str, or pathlib.Path, optional
Filename to store results. If not given, the filename will
consist of the name of the colormap and extension '.json'.
"""
colors = []
for i,c in enumerate(np.round(self.colors,6).tolist()):
colors+=[i]+c
out = [{
'Creator':util.execution_stamp('Colormap'),
'ColorSpace':'RGB',
'Name':self.name,
'DefaultMap':True,
'RGBPoints':colors
}]
json.dump(out,self._get_file_handle(fname,'json'),indent=4)
def save_ASCII(self,fname=None):
"""
Save as ASCII file.
Parameters
----------
fname : file, str, or pathlib.Path, optional
Filename to store results. If not given, the filename will
consist of the name of the colormap and extension '.txt'.
"""
labels = {'RGBA':4} if self.colors.shape[1] == 4 else {'RGB': 3}
t = Table(self.colors,labels,f'Creator: {util.execution_stamp("Colormap")}')
t.save(self._get_file_handle(fname,'txt'))
def save_GOM(self,fname=None):
"""
Save as ASCII file for use in GOM Aramis.
Parameters
----------
fname : file, str, or pathlib.Path, optional
Filename to store results. If not given, the filename will
consist of the name of the colormap and extension '.legend'.
"""
# ToDo: test in GOM
GOM_str = '1 1 {name} 9 {name} '.format(name=self.name.replace(" ","_")) \
+ '0 1 0 3 0 0 -1 9 \\ 0 0 0 255 255 255 0 0 255 ' \
+ f'30 NO_UNIT 1 1 64 64 64 255 1 0 0 0 0 0 0 3 0 {len(self.colors)}' \
+ ' '.join([f' 0 {c[0]} {c[1]} {c[2]} 255 1' for c in reversed((self.colors*255).astype(int))]) \
+ '\n'
self._get_file_handle(fname,'legend').write(GOM_str)
def save_gmsh(self,fname=None):
"""
Save as ASCII file for use in gmsh.
Parameters
----------
fname : file, str, or pathlib.Path, optional
Filename to store results. If not given, the filename will
consist of the name of the colormap and extension '.msh'.
"""
# ToDo: test in gmsh
gmsh_str = 'View.ColorTable = {\n' \
+'\n'.join([f'{c[0]},{c[1]},{c[2]},' for c in self.colors[:,:3]*255]) \
+'\n}\n'
self._get_file_handle(fname,'msh').write(gmsh_str)
@staticmethod
def _interpolate_msh(frac,low,high):
"""
Interpolate in Msh color space.
This interpolation gives a perceptually uniform colormap.
References
----------
https://www.kennethmoreland.com/color-maps/ColorMapsExpanded.pdf
https://www.kennethmoreland.com/color-maps/diverging_map.py
"""
def rad_diff(a,b):
return abs(a[2]-b[2])
def adjust_hue(msh_sat, msh_unsat):
"""If saturation of one of the two colors is much less than the other, hue of the less."""
if msh_sat[0] >= msh_unsat[0]:
return msh_sat[2]
else:
hSpin = msh_sat[1]/np.sin(msh_sat[1])*np.sqrt(msh_unsat[0]**2.0-msh_sat[0]**2)/msh_sat[0]
if msh_sat[2] < - np.pi/3.0: hSpin *= -1.0
return msh_sat[2] + hSpin
lo = np.array(low)
hi = np.array(high)
if (lo[1] > 0.05 and hi[1] > 0.05 and rad_diff(lo,hi) > np.pi/3.0):
M_mid = max(lo[0],hi[0],88.0)
if frac < 0.5:
hi = np.array([M_mid,0.0,0.0])
frac *= 2.0
else:
lo = np.array([M_mid,0.0,0.0])
frac = 2.0*frac - 1.0
if lo[1] < 0.05 and hi[1] > 0.05:
lo[2] = adjust_hue(hi,lo)
elif lo[1] > 0.05 and hi[1] < 0.05:
hi[2] = adjust_hue(lo,hi)
return (1.0 - frac) * lo + frac * hi
_predefined_mpl= {'Perceptually Uniform Sequential': [
'viridis', 'plasma', 'inferno', 'magma', 'cividis'],
'Sequential': [
'Greys', 'Purples', 'Blues', 'Greens', 'Oranges', 'Reds',
'YlOrBr', 'YlOrRd', 'OrRd', 'PuRd', 'RdPu', 'BuPu',
'GnBu', 'PuBu', 'YlGnBu', 'PuBuGn', 'BuGn', 'YlGn'],
'Sequential (2)': [
'binary', 'gist_yarg', 'gist_gray', 'gray', 'bone', 'pink',
'spring', 'summer', 'autumn', 'winter', 'cool', 'Wistia',
'hot', 'afmhot', 'gist_heat', 'copper'],
'Diverging': [
'PiYG', 'PRGn', 'BrBG', 'PuOr', 'RdGy', 'RdBu',
'RdYlBu', 'RdYlGn', 'Spectral', 'coolwarm', 'bwr', 'seismic'],
'Cyclic': ['twilight', 'twilight_shifted', 'hsv'],
'Qualitative': [
'Pastel1', 'Pastel2', 'Paired', 'Accent',
'Dark2', 'Set1', 'Set2', 'Set3',
'tab10', 'tab20', 'tab20b', 'tab20c'],
'Miscellaneous': [
'flag', 'prism', 'ocean', 'gist_earth', 'terrain', 'gist_stern',
'gnuplot', 'gnuplot2', 'CMRmap', 'cubehelix', 'brg',
'gist_rainbow', 'rainbow', 'jet', 'nipy_spectral', 'gist_ncar']}
_predefined_DAMASK = {'orientation': {'low': [0.933334,0.878432,0.878431],
'high': [0.250980,0.007843,0.000000]},
'strain': {'low': [0.941177,0.941177,0.870588],
'high': [0.266667,0.266667,0.000000]},
'stress': {'low': [0.878432,0.874511,0.949019],
'high': [0.000002,0.000000,0.286275]}}
predefined = dict(**{'DAMASK':list(_predefined_DAMASK)},**_predefined_mpl)
@staticmethod
def _hsv2rgb(hsv):
"""H(ue) S(aturation) V(alue) to R(red) G(reen) B(lue)."""
return np.array(colorsys.hsv_to_rgb(hsv[0]/360.,hsv[1],hsv[2]))
@staticmethod
def _rgb2hsv(rgb):
"""R(ed) G(reen) B(lue) to H(ue) S(aturation) V(alue)."""
h,s,v = colorsys.rgb_to_hsv(rgb[0],rgb[1],rgb[2])
return np.array([h*360,s,v])
@staticmethod
def _hsl2rgb(hsl):
"""H(ue) S(aturation) L(uminance) to R(red) G(reen) B(lue)."""
return np.array(colorsys.hls_to_rgb(hsl[0]/360.,hsl[2],hsl[1]))
@staticmethod
def _rgb2hsl(rgb):
"""R(ed) G(reen) B(lue) to H(ue) S(aturation) L(uminance)."""
h,l,s = colorsys.rgb_to_hls(rgb[0],rgb[1],rgb[2])
return np.array([h*360,s,l])
@staticmethod
def _xyz2rgb(xyz):
"""
CIE Xyz to R(ed) G(reen) B(lue).
References
----------
https://www.easyrgb.com/en/math.php
"""
rgb_lin = np.dot(np.array([
[ 3.240969942,-1.537383178,-0.498610760],
[-0.969243636, 1.875967502, 0.041555057],
[ 0.055630080,-0.203976959, 1.056971514]
]),xyz)
with np.errstate(invalid='ignore'):
rgb = np.where(rgb_lin>0.0031308,rgb_lin**(1.0/2.4)*1.0555-0.0555,rgb_lin*12.92)
return np.clip(rgb,0.,1.)
@staticmethod
def _rgb2xyz(rgb):
"""
R(ed) G(reen) B(lue) to CIE Xyz.
References
----------
https://www.easyrgb.com/en/math.php
"""
rgb_lin = np.where(rgb>0.04045,((rgb+0.0555)/1.0555)**2.4,rgb/12.92)
return np.dot(np.array([
[0.412390799,0.357584339,0.180480788],
[0.212639006,0.715168679,0.072192315],
[0.019330819,0.119194780,0.950532152]
]),rgb_lin)
@staticmethod
def _lab2xyz(lab,ref_white=None):
"""
CIE Lab to CIE Xyz.
References
----------
http://www.brucelindbloom.com/index.html?Eqn_Lab_to_XYZ.html
"""
f_x = (lab[0]+16.)/116. + lab[1]/500.
f_z = (lab[0]+16.)/116. - lab[2]/200.
return np.array([
f_x**3. if f_x**3. > _eps else (116.*f_x-16.)/_kappa,
((lab[0]+16.)/116.)**3 if lab[0]>_kappa*_eps else lab[0]/_kappa,
f_z**3. if f_z**3. > _eps else (116.*f_z-16.)/_kappa
])*(ref_white if ref_white is not None else _ref_white)
@staticmethod
def _xyz2lab(xyz,ref_white=None):
"""
CIE Xyz to CIE Lab.
References
----------
http://www.brucelindbloom.com/index.html?Eqn_Lab_to_XYZ.html
"""
ref_white = ref_white if ref_white is not None else _ref_white
f = np.where(xyz/ref_white > _eps,(xyz/ref_white)**(1./3.),(_kappa*xyz/ref_white+16.)/116.)
return np.array([
116.0 * f[1] - 16.0,
500.0 * (f[0] - f[1]),
200.0 * (f[1] - f[2])
])
@staticmethod
def _lab2msh(lab):
"""
CIE Lab to Msh.
References
----------
https://www.kennethmoreland.com/color-maps/ColorMapsExpanded.pdf
https://www.kennethmoreland.com/color-maps/diverging_map.py
"""
M = np.linalg.norm(lab)
return np.array([
M,
np.arccos(lab[0]/M) if M>1e-8 else 0.,
np.arctan2(lab[2],lab[1]) if M>1e-8 else 0.,
])
@staticmethod
def _msh2lab(msh):
"""
Msh to CIE Lab.
References
----------
https://www.kennethmoreland.com/color-maps/ColorMapsExpanded.pdf
https://www.kennethmoreland.com/color-maps/diverging_map.py
"""
return np.array([
msh[0] * np.cos(msh[1]),
msh[0] * np.sin(msh[1]) * np.cos(msh[2]),
msh[0] * np.sin(msh[1]) * np.sin(msh[2])
])
@staticmethod
def _lab2rgb(lab):
return Colormap._xyz2rgb(Colormap._lab2xyz(lab))
@staticmethod
def _rgb2lab(rgb):
return Colormap._xyz2lab(Colormap._rgb2xyz(rgb))
@staticmethod
def _msh2rgb(msh):
return Colormap._lab2rgb(Colormap._msh2lab(msh))
@staticmethod
def _rgb2msh(rgb):
return Colormap._lab2msh(Colormap._rgb2lab(rgb))
@staticmethod
def _hsv2msh(hsv):
return Colormap._rgb2msh(Colormap._hsv2rgb(hsv))
@staticmethod
def _hsl2msh(hsl):
return Colormap._rgb2msh(Colormap._hsl2rgb(hsl))
@staticmethod
def _xyz2msh(xyz):
return Colormap._lab2msh(Colormap._xyz2lab(xyz))