1 '''Defines the Ghost class for theia.'''
2
3
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8
9
10 import numpy as np
11 from ..helpers.geometry import rectToSph, linePlaneInter
12 from ..helpers.units import deg, pi
13 from .component import SetupComponent
14 from .beam import GaussianBeam
15
16 -class Ghost(SetupComponent):
17 '''
18
19 Ghost class.
20
21 This class represents surfaces which don't interact with the beams. They
22 just transmit the same beam, and may be useful to monitor the beams on their
23 way, without having to calculate the Q yourself if you're looking for the
24 Q at another place than the origin of the beam.
25
26 Ghost surfaces basically have a null thickness and transmit the beams.
27
28 *=== Attributes ===*
29 SetupCount (inherited): class attribute, counts all setup components.
30 [integer]
31 Name: class attribute. [string]
32 HRCenter (inherited): center of the principal face of the Ghost in space.
33 [3D vector]
34 HRnorm (inherited): normal unitary vector the this principal face,
35 supposed to point outside the media. [3D vector]
36 Thick (inherited): thickness of the dump, counted in opposite direction to
37 HRNorm. [float]
38 Dia (inherited): diameter of the component. [float]
39 Ref (inherited): reference string (for keeping track with the lab). [string]
40
41 '''
42 Name = "Ghost"
43 - def __init__(self, X = 0., Y = 0., Z = 0., Theta = pi/2., Phi = 0.,
44 Ref = None, Diameter = 5.e-2):
45 '''Ghost initializer.
46
47 Parameters are the attributes.
48
49 Returns a Ghost.
50
51 '''
52
53 Diameter = float(Diameter)
54
55
56 Norm = np.array([np.sin(Theta)*np.cos(Phi),
57 np.sin(Theta) * np.sin(Phi),
58 np.cos(Theta)], dtype = np.float64)
59
60 HRCenter = np.array([X, Y, Z], dtype = np.float64)
61
62
63 super(Ghost, self).__init__(Ref = Ref,
64 Diameter = Diameter, HRCenter = HRCenter, HRNorm = Norm,
65 Thickness = 0.)
66
68 '''Return the list of lines needed to print the object.
69 '''
70 ans = []
71 ans.append("Ghost: {" %self.Ref)
72 ans.append("Diameter: %sm" %str(self.Dia))
73 ans.append("Center: %s" %str(self.HRCenter))
74 sph = rectToSph(self.HRNorm)
75 ans.append("Norm: (%s, %s)deg" %(str(sph[0]/deg), str(sph[1]/deg)))
76 ans.append("}")
77
78 return ans
79
81 '''Determine if a beam hits the Ghost surface.
82
83 This uses the linePlaneInter function from the geometry module to find
84 characteristics of impact of beams on ghost surfaces.
85
86 beam: incoming beam. [GaussianBeam]
87
88 Returns a dictionary with keys:
89 'isHit': whether the beam hits the dump. [boolean]
90 'intersection point': point in space where it is first hit.
91 [3D vector]
92 'face': to indicate which face is first hit, can be 'HR', 'AR' or
93 'side'. [string]
94 'distance': geometrical distance from beam origin to impact. [float]
95
96 '''
97
98 noInterDict = {'isHit': False,
99 'intersection point': np.array([0., 0., 0.],
100 dtype=np.float64),
101 'face': None,
102 'distance': 0.}
103
104
105 HRDict = linePlaneInter(beam.Pos, beam.Dir, self.HRCenter,
106 self.HRNorm, self.Dia)
107
108 if HRDict['isHit']:
109 return {'isHit': True,
110 'intersection point': HRDict['intersection point'],
111 'face': 'HR',
112 'distance': HRDict['distance']
113 }
114 else:
115 return noInterDict
116
117 - def hit(self, beam, order, threshold):
118 '''Return the beam simply transmitted by the ghost surface.
119
120 beam: incident beam. [GaussianBeam]
121 order: maximum strayness of daughter beams, which are not returned if
122 their strayness is over this order. [integer]
123 threshold: idem for the power of the daughter beams. [float]
124
125 Returns a dictionary of beams with keys:
126 't': Gaussian beam which is the continuity of the incident beam.
127
128 '''
129
130 dic = self.isHit(beam)
131 beam.Length = dic['distance']
132 beam.OptDist = beam.N * beam.Length
133
134
135 interactionPoint = dic['intersection point']
136
137
138 newQ = beam.Q(beam.Length)
139
140 return {'t': GaussianBeam(Q = newQ, N = beam.N, Wl = beam.Wl,
141 P = beam.P, Pos = interactionPoint, Dir = beam.Dir,
142 Ux = beam.U[0], Uy = beam.U[1], Ref = beam.Ref,
143 OptDist = 0., Length = 0., StrayOrder = beam.StrayOrder,
144 Optic = self.Ref, Face = ''),
145 'r': None}
146