1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
|
use crate::*;
// Make Edge-Vertex
pub struct Melf<'brand, 'arena, V> {
pub vertices: [ptr!(Vertex); 2],
pub loop_: ptr!(Loop),
}
impl<'brand, 'arena, V> Melf<'brand, 'arena, V> {
pub fn new(vertices: [ptr!(Vertex); 2], loop_: ptr!(Loop)) -> Self {
Self { vertices, loop_ }
}
}
#[derive(Debug, Error)]
pub enum MelfError {
#[error("vertex is not part of loop")]
VertexLoopMismatch,
}
impl<'brand, 'arena, V> Operator<'brand, 'arena, V> for Melf<'brand, 'arena, V> {
type Inverse = Kelf<'brand, 'arena, V>;
type Error = MelfError;
type Check = [ptr!(HalfEdge); 2];
fn check(&self, dcel: &Dcel<'brand, 'arena, V>) -> Result<Self::Check, Self::Error> {
let b0 = self.vertices[0]
.find_outgoing(self.loop_, dcel)
.ok_or(MelfError::VertexLoopMismatch)?;
let a2 = self.vertices[1]
.find_outgoing(self.loop_, dcel)
.ok_or(MelfError::VertexLoopMismatch)?;
Ok([b0, a2])
}
fn apply(
self,
dcel: &mut Dcel<'brand, 'arena, V>,
) -> Result<Self::Inverse, OperatorErr<Self, Self::Error>> {
// before:
// > >
// a0 \ / a2
// v1 v2
// b0 / \ b2
// < <
//
// after:
// > >
// a0 \ a1 -> / a2
// v1 v2
// b0 / <- b1 \ b2
// < <
//
let [b0, a2] = try_check!(self, dcel);
let a0 = b0.prev(dcel);
let b2 = a2.prev(dcel);
let old_loop = self.loop_;
let [v1, v2] = self.vertices;
let shell = old_loop.face(dcel).shell(dcel);
let (edge, [a1, b1]) = Edge::create(shell, dcel);
let face = shell.add_new_face(dcel);
let new_loop = Loop::new(dcel); // face.add_new_outer_loop(self);
new_loop.set_face(*face, dcel);
face.set_outer_loop(*new_loop, dcel);
a1.update_origin(v1, dcel);
dcel.follow(a0, a1);
dcel.follow(a1, a2);
old_loop.set_half_edges(a1, dcel);
a1.set_loop_(old_loop, dcel);
b1.update_origin(v2, dcel);
dcel.follow(b2, b1);
dcel.follow(b1, b0);
new_loop.set_half_edges(b1, dcel);
new_loop.update_connectivity(dcel);
Ok(Kelf {
loop_: new_loop,
edge,
face,
})
}
}
pub struct Kelf<'brand, 'arena, V> {
pub edge: own!(Edge),
pub loop_: own!(Loop),
pub face: own!(Face),
}
impl<'brand, 'arena, V> Kelf<'brand, 'arena, V> {
pub fn new(edge: own!(Edge), loop_: own!(Loop), face: own!(Face)) -> Self {
Self { edge, loop_, face }
}
}
#[derive(Debug, Error)]
pub enum KelfError {
#[error("edge is not part of loop")]
EdgeLoopMismatch,
#[error("loop is not outer loop of face")]
FaceLoopMismatch,
#[error("face has inner loops")]
HasInnerLoops,
}
impl<'brand, 'arena, V> Operator<'brand, 'arena, V> for Kelf<'brand, 'arena, V> {
type Inverse = Melf<'brand, 'arena, V>;
type Error = KelfError;
type Check = [ptr!(HalfEdge); 2];
fn check(&self, dcel: &Dcel<'brand, 'arena, V>) -> Result<Self::Check, Self::Error> {
use KelfError::*;
let [mut a1, mut b1] = self.edge.lens(dcel).half_edges();
if a1.loop_().eq(*self.loop_) {
[a1, b1] = [b1, a1];
}
or_err(b1.loop_().eq(*self.loop_), EdgeLoopMismatch)?;
or_err(
self.face.outer_loop(dcel).eq(*self.loop_, dcel),
FaceLoopMismatch,
)?;
or_err(self.face.maybe_inner_loops(dcel).is_none(), HasInnerLoops)?;
Ok([a1.item, b1.item])
}
fn apply(
self,
dcel: &mut Dcel<'brand, 'arena, V>,
) -> Result<Self::Inverse, OperatorErr<Self, Self::Error>> {
let [a1, b1] = try_check!(self, dcel);
let Kelf { edge, loop_, face } = self;
let shell = face.shell(dcel);
let a0 = a1.prev(dcel);
let b0 = b1.next(dcel);
let a2 = a1.next(dcel);
let b2 = b1.prev(dcel);
let v1 = a1.origin(dcel);
let v2 = b1.origin(dcel);
let old_loop = a1.loop_(dcel);
dcel.follow(a0, b0);
dcel.follow(b2, a2);
old_loop.set_half_edges(a0, dcel);
old_loop.update_connectivity(dcel);
shell.remove_edge(*edge, dcel);
shell.remove_face(*face, dcel);
edge.destroy(dcel);
face.free(dcel);
loop_.free(dcel);
Ok(Melf {
vertices: [v1, v2],
loop_: old_loop,
})
}
}
|
