def transform_grid_from_reference_frame(self, grid):
"""Transform a grid of (y,x) coordinates from the reference frame of the profile to the original observer \
reference frame, including a rotation to its original orientation and a translation from the profile's centre.
Parameters
----------
grid
The (y, x) coordinates in the reference frame of the profile.
"""
if self.__class__.__name__.startswith("Sph"):
return super().transform_grid_from_reference_frame(
grid=grid_2d.Grid2DTransformedNumpy(grid=grid))
return geometry_util.transform_grid_2d_from_reference_frame(
grid_2d=grid, centre=self.centre, angle=self.angle)
def rotate_grid_from_reference_frame(self, grid):
"""
Rotate a grid of (y,x) coordinates which have been transformed to the elliptical reference frame of a profile
back to the original unrotated coordinate grid reference frame.
Note that unlike the method `transform_grid_from_reference_frame` the the coordinates are not
translated back to the profile's original centre.
This routine is used after computing deflection angles in the reference frame of the profile, so that the
deflection angles can be re-rotated to the frame of the original coordinates before performing ray-tracing.
Parameters
----------
grid
The (y, x) coordinates in the reference frame of an elliptical profile.
"""
return geometry_util.transform_grid_2d_from_reference_frame(
grid_2d=grid, centre=(0.0, 0.0), angle=self.angle)
def grid_2d_radial_projected_from(
self,
centre=(0.0, 0.0),
angle: float = 0.0) -> grid_2d_irregular.Grid2DIrregular:
"""
Determine a projected radial grid of points from a 2D region of coordinates defined by an
extent [xmin, xmax, ymin, ymax] and with a (y,x) centre. This functions operates as follows:
1) Given the region defined by the extent [xmin, xmax, ymin, ymax], the algorithm finds the longest 1D distance
of the 4 paths from the (y,x) centre to the edge of the region (e.g. following the positive / negative y and
x axes).
2) Use the pixel-scale corresponding to the direction chosen (e.g. if the positive x-axis was the longest, the
pixel_scale in the x dimension is used).
3) Determine the number of pixels between the centre and the edge of the region using the longest path between
the two chosen above.
4) Create a (y,x) grid of radial points where all points are at the centre's y value = 0.0 and the x values
iterate from the centre in increasing steps of the pixel-scale.
5) Rotate these radial coordinates by the input `angle` clockwise.
A schematic is shown below:
-------------------
| |
|<- - - - ->x | x = centre
| | <-> = longest radial path from centre to extent edge
| |
-------------------
4) Create a (y,x) grid of radial points where all points are at the centre's y value = 0.0 and the x values
iterate from the centre in increasing steps of the pixel-scale.
5) Rotate these radial coordinates by the input `angle` clockwise.
Parameters
----------
extent : np.ndarray
The extent of the grid the radii grid is computed using, with format [xmin, xmax, ymin, ymax]
centre : (float, flloat)
The (y,x) central coordinate which the radial grid is traced outwards from.
pixel_scales : (float, float)
The (y,x) scaled units to pixel units conversion factor of the 2D mask array.
sub_size : int
The size of the sub-grid that each pixel of the 2D mask array is divided into.
angle : float
The angle with which the radial coordinates are rotated clockwise.
Returns
-------
grid_2d_irregular.Grid2DIrregular
A radial set of points sampling the longest distance from the centre to the edge of the extent in along the
positive x-axis.
"""
grid_radial_projected_2d = grid_2d_util.grid_scaled_2d_slim_radial_projected_from(
extent=self.extent,
centre=centre,
pixel_scales=self.pixel_scales,
sub_size=self.sub_size,
)
grid_radial_projected_2d = geometry_util.transform_grid_2d_to_reference_frame(
grid_2d=grid_radial_projected_2d, centre=centre, angle=angle)
grid_radial_projected_2d = geometry_util.transform_grid_2d_from_reference_frame(
grid_2d=grid_radial_projected_2d, centre=centre, angle=0.0)
return grid_2d_irregular.Grid2DIrregular(grid=grid_radial_projected_2d)