"""Plot sound fields etc."""
import matplotlib.pyplot as plt
from matplotlib.patches import PathPatch
from matplotlib.path import Path
from matplotlib.collections import PatchCollection
from mpl_toolkits.mplot3d import Axes3D
import numpy as np
from . import util
def _register_coolwarm_clip():
"""Create color map with "over" and "under" values."""
from matplotlib.colors import LinearSegmentedColormap
# The 'coolwarm' colormap is based on the paper
# "Diverging Color Maps for Scientific Visualization" by Kenneth Moreland
# http://www.sandia.gov/~kmorel/documents/ColorMaps/
cdict = plt.cm.datad['coolwarm']
cmap = LinearSegmentedColormap('coolwarm_clip', cdict)
cmap.set_over(color=cmap(1.0), alpha=0.7)
cmap.set_under(color=cmap(0.0), alpha=0.7)
plt.cm.register_cmap(cmap=cmap)
_register_coolwarm_clip()
del _register_coolwarm_clip
[docs]def virtualsource_2d(xs, ns=None, type='point', ax=None):
"""Draw position/orientation of virtual source."""
xs = np.asarray(xs)
ns = np.asarray(ns)
if ax is None:
ax = plt.axes()
if type == 'point':
vps = plt.Circle(xs, .05, edgecolor='k', facecolor='k')
ax.add_artist(vps)
for n in range(1, 3):
vps = plt.Circle(xs, .05+n*0.05, edgecolor='k', fill=False)
ax.add_artist(vps)
elif type == 'plane':
ns = 0.2 * ns
ax.arrow(xs[0], xs[1], ns[0], ns[1], head_width=0.05,
head_length=0.1, fc='k', ec='k')
[docs]def reference_2d(xref, size=0.1, ax=None):
"""Draw reference/normalization point."""
xref = np.asarray(xref)
if ax is None:
ax = plt.axes()
ax.plot((xref[0]-size, xref[0]+size), (xref[1]-size, xref[1]+size), 'k-')
ax.plot((xref[0]-size, xref[0]+size), (xref[1]+size, xref[1]-size), 'k-')
[docs]def secondarysource_2d(x0, n0, grid=None):
"""Simple plot of secondary source locations."""
x0 = np.asarray(x0)
n0 = np.asarray(n0)
ax = plt.axes()
# plot only secondary sources inside simulated area
if grid is not None:
x0, n0 = _visible_secondarysources_2d(x0, n0, grid)
# plot symbols
for x00 in x0:
ss = plt.Circle(x00[0:2], .05, edgecolor='k', facecolor='k')
ax.add_artist(ss)
[docs]def loudspeaker_2d(x0, n0, a0=0.5, size=0.08, show_numbers=False, grid=None,
ax=None):
"""Draw loudspeaker symbols at given locations and angles.
Parameters
----------
x0 : (N, 3) array_like
Loudspeaker positions.
n0 : (N, 3) or (3,) array_like
Normal vector(s) of loudspeakers.
a0 : float or (N,) array_like, optional
Weighting factor(s) of loudspeakers.
size : float, optional
Size of loudspeakers in metres.
show_numbers : bool, optional
If ``True``, loudspeaker numbers are shown.
grid : triple of numpy.ndarray, optional
If specified, only loudspeakers within the `grid` are shown.
ax : Axes object, optional
The loudspeakers are plotted into this
:class:`~matplotlib.axes.Axes` object or -- if not specified --
into the current axes.
"""
x0 = util.asarray_of_rows(x0)
n0 = util.asarray_of_rows(n0)
a0 = util.asarray_1d(a0).reshape(-1, 1)
# plot only secondary sources inside simulated area
if grid is not None:
x0, n0 = _visible_secondarysources_2d(x0, n0, grid)
# normalized coordinates of loudspeaker symbol (see IEC 60617-9)
codes, coordinates = zip(*(
(Path.MOVETO, [-0.62, 0.21]),
(Path.LINETO, [-0.31, 0.21]),
(Path.LINETO, [0, 0.5]),
(Path.LINETO, [0, -0.5]),
(Path.LINETO, [-0.31, -0.21]),
(Path.LINETO, [-0.62, -0.21]),
(Path.CLOSEPOLY, [0, 0]),
(Path.MOVETO, [-0.31, 0.21]),
(Path.LINETO, [-0.31, -0.21]),
))
coordinates = np.column_stack([coordinates, np.zeros(len(coordinates))])
coordinates *= size
patches = []
for x00, n00 in util.broadcast_zip(x0, n0):
# rotate and translate coordinates
R = util.rotation_matrix([1, 0, 0], n00)
transformed_coordinates = np.inner(coordinates, R) + x00
patches.append(PathPatch(Path(transformed_coordinates[:, :2], codes)))
# add collection of patches to current axis
p = PatchCollection(patches, edgecolor='0', facecolor=np.tile(1 - a0, 3))
if ax is None:
ax = plt.gca()
ax.add_collection(p)
if show_numbers:
for idx, (x00, n00) in enumerate(util.broadcast_zip(x0, n0)):
x, y = x00[:2] - 1.2 * size * n00[:2]
ax.text(x, y, idx + 1, horizontalalignment='center',
verticalalignment='center')
def _visible_secondarysources_2d(x0, n0, grid):
"""Determine secondary sources which lie within `grid`."""
grid = util.asarray_of_arrays(grid)
x, y = grid[:2]
idx = np.where((x0[:, 0] > x.min()) & (x0[:, 0] < x.max()) &
(x0[:, 1] > y.min()) & (x0[:, 1] < x.max()))
idx = np.squeeze(idx)
return x0[idx, :], n0[idx, :]
[docs]def loudspeaker_3d(x0, n0, a0=None, w=0.08, h=0.08):
"""Plot positions and normals of a 3D secondary source distribution."""
fig = plt.figure(figsize=(15, 15))
ax = fig.add_subplot(111, projection='3d')
ax.quiver(x0[:, 0], x0[:, 1], x0[:, 2], n0[:, 0],
n0[:, 1], n0[:, 2], length=0.1)
plt.xlabel('x (m)')
plt.ylabel('y (m)')
plt.title('Secondary Sources')
fig.show()
[docs]def soundfield(p, grid, xnorm=None, colorbar=True, cmap='coolwarm_clip',
ax=None, xlabel='x (m)', ylabel='y (m)', vmax=2.0, vmin=-2.0,
**kwargs):
"""Two-dimensional plot of sound field."""
grid = util.asarray_of_arrays(grid)
# normalize sound field wrt xnorm
if xnorm is not None:
p = util.normalize(p, grid, xnorm)
x, y = grid[:2] # ignore z-component
if ax is None:
ax = plt.gca()
im = ax.imshow(np.real(p), cmap=cmap, origin='lower',
extent=[x.min(), x.max(), y.min(), y.max()],
vmax=vmax, vmin=vmin, aspect='equal', **kwargs)
ax.set_adjustable('box-forced') # avoid empty space btw. axis and image
if xlabel:
ax.set_xlabel(xlabel)
if ylabel:
ax.set_ylabel(ylabel)
if colorbar:
ax.figure.colorbar(im, ax=ax)
return im
[docs]def level(p, grid, xnorm=None, colorbar=True, cmap='coolwarm_clip',
ax=None, xlabel='x (m)', ylabel='y (m)', vmax=3.0, vmin=-50,
**kwargs):
"""Two-dimensional plot of level (dB) of sound field."""
# normalize sound field wrt xnorm
if xnorm is not None:
p = util.normalize(p, grid, xnorm)
xnorm = None
im = soundfield(20*np.log10(np.abs(p)), grid, xnorm, colorbar, cmap, ax,
xlabel, ylabel, vmax, vmin, **kwargs)
return im