# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""
This module defines point regions in both pixel and sky coordinates.
"""
import numpy as np
from regions.core.attributes import (RegionMetaDescr, RegionVisualDescr,
ScalarPixCoord, ScalarSkyCoord)
from regions.core.bounding_box import RegionBoundingBox
from regions.core.core import PixelRegion, SkyRegion
from regions.core.metadata import RegionMeta, RegionVisual
from regions.core.pixcoord import PixCoord
__all__ = ['PointPixelRegion', 'PointSkyRegion']
[docs]
class PointPixelRegion(PixelRegion):
"""
A point position in pixel coordinates.
Parameters
----------
center : `~regions.PixCoord`
The position of the point.
meta : `~regions.RegionMeta` or `dict`, optional
A dictionary that stores the meta attributes of the region.
visual : `~regions.RegionVisual` or `dict`, optional
A dictionary that stores the visual meta attributes of the
region.
Examples
--------
.. plot::
:include-source:
from regions import PixCoord, PointPixelRegion, RegionVisual
import matplotlib.pyplot as plt
fig, ax = plt.subplots(1, 1)
regs = []
regs.append(PointPixelRegion(PixCoord(2, 2),
visual=RegionVisual(marker='D')))
regs.append(PointPixelRegion(PixCoord(2, 3),
visual=RegionVisual(marker='+')))
regs.append(PointPixelRegion(PixCoord(3, 3),
visual=RegionVisual(marker='^')))
regs.append(PointPixelRegion(PixCoord(3, 2),
visual=RegionVisual(marker='*')))
regs.append(PointPixelRegion(PixCoord(2, 4),
visual=RegionVisual(marker='x')))
regs.append(PointPixelRegion(PixCoord(4, 2)))
for reg in regs:
reg.plot(ax=ax)
ax.set_xlim(0, 6)
ax.set_ylim(0, 6)
ax.set_aspect('equal')
"""
_params = ('center',)
_mpl_artist = 'Line2D'
center = ScalarPixCoord('The point pixel position as a |PixCoord|.')
meta = RegionMetaDescr('The meta attributes as a |RegionMeta|')
visual = RegionVisualDescr('The visual attributes as a |RegionVisual|.')
def __init__(self, center, meta=None, visual=None):
self.center = center
self.meta = meta or RegionMeta()
self.visual = visual or RegionVisual()
@property
def area(self):
return 0.0
[docs]
def contains(self, pixcoord):
if pixcoord.isscalar:
in_reg = False
else:
in_reg = np.zeros(pixcoord.x.shape, dtype=bool)
if self.meta.get('include', True):
# in_reg = False, always. Points do not include anything.
return in_reg
else:
return np.logical_not(in_reg)
[docs]
def to_sky(self, wcs):
center = wcs.pixel_to_world(self.center.x, self.center.y)
return PointSkyRegion(center, meta=self.meta.copy(),
visual=self.visual.copy())
@property
def bounding_box(self):
return RegionBoundingBox.from_float(self.center.x, self.center.x,
self.center.y, self.center.y)
[docs]
def to_mask(self, mode='center', subpixels=5):
# TODO: needs to be implemented
raise NotImplementedError
[docs]
def as_artist(self, origin=(0, 0), **kwargs):
"""
Return a matplotlib Line2D object for this region
(`matplotlib.lines.Line2D`).
Parameters
----------
origin : array_like, optional
The ``(x, y)`` pixel position of the origin of the displayed
image.
**kwargs : `dict`
Any keyword arguments accepted by
`~matplotlib.lines.Line2D`. These keywords will override any
visual meta attributes of this region.
Returns
-------
artist : `~matplotlib.lines.Line2D`
A matplotlib Line2D object.
"""
from matplotlib.lines import Line2D
mpl_kwargs = self.visual.define_mpl_kwargs(self._mpl_artist)
mpl_kwargs.update(kwargs)
return Line2D([self.center.x - origin[0]],
[self.center.y - origin[1]], **mpl_kwargs)
[docs]
def rotate(self, center, angle):
"""
Rotate the region.
Positive ``angle`` corresponds to counter-clockwise rotation.
Parameters
----------
center : `~regions.PixCoord`
The rotation center point.
angle : `~astropy.coordinates.Angle`
The rotation angle.
Returns
-------
region : `PointPixelRegion`
The rotated region (which is an independent copy).
"""
center = self.center.rotate(center, angle)
return self.copy(center=center)
[docs]
class PointSkyRegion(SkyRegion):
"""
A pixel region in sky coordinates.
Parameters
----------
center : `~astropy.coordinates.SkyCoord`
The position of the point.
meta : `~regions.RegionMeta` or `dict`, optional
A dictionary that stores the meta attributes of the region.
visual : `~regions.RegionVisual` or `dict`, optional
A dictionary that stores the visual meta attributes of the
region.
"""
_params = ('center',)
center = ScalarSkyCoord('The point position as a |SkyCoord|.')
meta = RegionMetaDescr('The meta attributes as a |RegionMeta|')
visual = RegionVisualDescr('The visual attributes as a |RegionVisual|.')
def __init__(self, center, meta=None, visual=None):
self.center = center
self.meta = meta or RegionMeta()
self.visual = visual or RegionVisual()
[docs]
def contains(self, skycoord, wcs): # pylint: disable=unused-argument
if self.meta.get('include', True):
# points never include anything
return False
else:
return True
[docs]
def to_pixel(self, wcs):
center_x, center_y = wcs.world_to_pixel(self.center)
center = PixCoord(center_x, center_y)
return PointPixelRegion(center, meta=self.meta.copy(),
visual=self.visual.copy())