fuchsia_scenic/
flatland.rs

1// Copyright 2021 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5use anyhow::Error;
6
7pub use fidl_fuchsia_scenic_scheduling::PresentationInfo;
8pub use fidl_fuchsia_ui_composition::{
9    ChildViewWatcherMarker, ContentId, FlatlandDisplayMarker, FlatlandDisplayProxy, FlatlandError,
10    FlatlandEvent, FlatlandEventStream, FlatlandMarker, FlatlandProxy, LayoutInfo,
11    ParentViewportWatcherMarker, ParentViewportWatcherProxy, PresentArgs, TransformId,
12    ViewBoundProtocols, ViewportProperties,
13};
14pub use fidl_fuchsia_ui_views::{ViewCreationToken, ViewportCreationToken};
15
16// Pair of tokens used to link two Flatland sessions together.
17pub struct ViewCreationTokenPair {
18    pub view_creation_token: ViewCreationToken,
19    pub viewport_creation_token: ViewportCreationToken,
20}
21
22impl ViewCreationTokenPair {
23    pub fn new() -> Result<ViewCreationTokenPair, Error> {
24        let (view_creation_token, viewport_creation_token) = zx::Channel::create();
25        Ok(ViewCreationTokenPair {
26            view_creation_token: ViewCreationToken { value: view_creation_token },
27            viewport_creation_token: ViewportCreationToken { value: viewport_creation_token },
28        })
29    }
30}
31
32/// IdGenerator generates a monotonically-increasing sequence of IDs, either TransformIds or
33/// ContentIds, depending on what the caller asks for.  The ID values are unique both across and
34/// within ID types, e.g. a given IdGenerator will not generate two TransformIds with the same
35/// value, nor a TransformId and a ContentId with the same value.
36pub struct IdGenerator {
37    next_id: u64,
38}
39
40impl IdGenerator {
41    pub fn new() -> Self {
42        IdGenerator { next_id: 1 }
43    }
44
45    pub fn new_with_first_id(first_id: u64) -> Self {
46        IdGenerator { next_id: first_id }
47    }
48
49    pub fn next_transform_id(&mut self) -> TransformId {
50        let id = self.next_id;
51        self.next_id += 1;
52        TransformId { value: id }
53    }
54
55    pub fn next_content_id(&mut self) -> ContentId {
56        let id = self.next_id;
57        self.next_id += 1;
58        ContentId { value: id }
59    }
60}
61
62#[cfg(test)]
63mod tests {
64    use super::*;
65
66    #[test]
67    fn id_generator_basic() {
68        let mut generator = IdGenerator::new();
69        assert_eq!(generator.next_content_id(), ContentId { value: 1 });
70        assert_eq!(generator.next_content_id(), ContentId { value: 2 });
71        assert_eq!(generator.next_transform_id(), TransformId { value: 3 });
72        assert_eq!(generator.next_transform_id(), TransformId { value: 4 });
73    }
74
75    #[test]
76    fn id_generator_with_first_id() {
77        let mut generator = IdGenerator::new_with_first_id(11);
78        assert_eq!(generator.next_transform_id(), TransformId { value: 11 });
79    }
80}
fuchsia_scenic/flatland.rs

fuchsia_scenic/
flatland.rs
