1# https://pyrocko.org - GPLv3 

2# 

3# The Pyrocko Developers, 21st Century 

4# ---|P------/S----------~Lg---------- 

5 

6import numpy as num 

7 

8from pyrocko.guts import Object, Int 

9 

10from pyrocko import icosphere, geometry as g 

11 

12guts_prefix = 'sparrow' 

13 

14and_ = num.logical_and 

15 

16 

17class Level(object): 

18 def __init__(self, vertices, faces): 

19 self.vertices = vertices 

20 self.faces = faces 

21 self.next = None 

22 self.nvertices = vertices.shape[0] 

23 self.nfaces = faces.shape[0] 

24 self.prepare_projections() 

25 

26 def points_in_face(self, iface, points): 

27 uv = g.triangle_barycentric_coordinates( 

28 self.bary_trans[iface, :, :], 

29 self.vertices[self.faces[iface, 0]], 

30 points) 

31 

32 return and_( 

33 and_(uv[:, 0] >= 0., uv[:, 1] >= 0.), uv[:, 0] + uv[:, 1] <= 1.) 

34 

35 def points_to_face(self, points, icandidates=None): 

36 

37 if icandidates is None: 

38 icandidates = num.arange(self.nfaces) 

39 

40 npoints = points.shape[0] 

41 ifaces = num.zeros(npoints, dtype=int) 

42 points_flat_all = num.zeros((npoints, 3)) 

43 for icandidate in icandidates: 

44 points_flat, mask = self.project(icandidate, points) 

45 ipoints = num.where(num.logical_and( 

46 self.points_in_face(icandidate, points_flat), 

47 mask))[0] 

48 

49 if self.next: 

50 icandidates_child = num.where( 

51 self.next.parents == icandidate)[0] 

52 ifaces[ipoints], points_flat_all[ipoints, :] \ 

53 = self.next.points_to_face( 

54 points[ipoints], icandidates_child) 

55 

56 else: 

57 ifaces[ipoints] = icandidate 

58 points_flat_all[ipoints, :] = points_flat[ipoints, :] 

59 

60 return ifaces, points_flat_all 

61 

62 def project(self, iface, points): 

63 denom = g.vdot(points, self.aplanes[iface, :]) 

64 mask = denom > 0.0 

65 points = points.copy() 

66 points[mask, :] /= denom[mask, num.newaxis] 

67 points[num.logical_not(mask), :] = 0.0 

68 return points, mask 

69 

70 def prepare_projections(self): 

71 planes = g.triangle_planes( 

72 self.vertices, self.faces) 

73 

74 planes /= g.vdot( 

75 planes, 

76 self.vertices[self.faces[:, 0]])[:, num.newaxis] 

77 

78 self.aplanes = planes 

79 

80 self.bary_trans = g.triangle_barycentric_transforms( 

81 self.vertices, self.faces) 

82 

83 

84class HiMesh(Object): 

85 

86 order = Int.T(default=0) 

87 

88 def __init__(self, **kwargs): 

89 Object.__init__(self, **kwargs) 

90 self.levels = self.make_levels() 

91 

92 def make_levels(self): 

93 # root = None 

94 level = None 

95 levels = [] 

96 for vertices, faces in icosphere.iter_icospheres( 

97 self.order, inflate=False): 

98 

99 new = Level(vertices, faces) 

100 if not levels: 

101 new.parents = None 

102 else: 

103 new.parents = g.refine_triangle_parents(faces.shape[0]) 

104 level.next = new 

105 

106 level = new 

107 levels.append(new) 

108 

109 return levels 

110 

111 def get_vertices(self): 

112 return g.normalize(self.levels[-1].vertices) 

113 

114 def get_faces(self): 

115 return self.levels[-1].faces 

116 

117 def points_to_faces(self, points): 

118 return self.levels[0].points_to_face(points)[0]