gdk_pixbuf/pixbuf_animation.rs
1// Take a look at the license at the top of the repository in the LICENSE file.
2
3use std::{ptr, time::SystemTime};
4
5use glib::{prelude::*, translate::*};
6
7use crate::{ffi, PixbufAnimation, PixbufAnimationIter};
8
9pub trait PixbufAnimationExtManual: IsA<PixbufAnimation> + 'static {
10 /// Get an iterator for displaying an animation.
11 ///
12 /// The iterator provides the frames that should be displayed at a
13 /// given time.
14 ///
15 /// @start_time would normally come from g_get_current_time(), and marks
16 /// the beginning of animation playback. After creating an iterator, you
17 /// should immediately display the pixbuf returned by
18 /// gdk_pixbuf_animation_iter_get_pixbuf(). Then, you should install
19 /// a timeout (with g_timeout_add()) or by some other mechanism ensure
20 /// that you'll update the image after
21 /// gdk_pixbuf_animation_iter_get_delay_time() milliseconds. Each time
22 /// the image is updated, you should reinstall the timeout with the new,
23 /// possibly-changed delay time.
24 ///
25 /// As a shortcut, if @start_time is `NULL`, the result of
26 /// g_get_current_time() will be used automatically.
27 ///
28 /// To update the image (i.e. possibly change the result of
29 /// gdk_pixbuf_animation_iter_get_pixbuf() to a new frame of the animation),
30 /// call gdk_pixbuf_animation_iter_advance().
31 ///
32 /// If you're using #GdkPixbufLoader, in addition to updating the image
33 /// after the delay time, you should also update it whenever you
34 /// receive the area_updated signal and
35 /// gdk_pixbuf_animation_iter_on_currently_loading_frame() returns
36 /// `TRUE`. In this case, the frame currently being fed into the loader
37 /// has received new data, so needs to be refreshed. The delay time for
38 /// a frame may also be modified after an area_updated signal, for
39 /// example if the delay time for a frame is encoded in the data after
40 /// the frame itself. So your timeout should be reinstalled after any
41 /// area_updated signal.
42 ///
43 /// A delay time of -1 is possible, indicating "infinite".
44 ///
45 /// # Deprecated since 2.44
46 ///
47 /// Use a different image loading library for animatable assets
48 /// ## `start_time`
49 /// time when the animation starts playing
50 ///
51 /// # Returns
52 ///
53 /// an iterator to move over the animation
54 #[doc(alias = "gdk_pixbuf_animation_get_iter")]
55 #[doc(alias = "get_iter")]
56 fn iter(&self, start_time: Option<SystemTime>) -> PixbufAnimationIter {
57 let start_time = start_time.map(|s| {
58 let diff = s
59 .duration_since(SystemTime::UNIX_EPOCH)
60 .expect("failed to convert time");
61 glib::ffi::GTimeVal {
62 tv_sec: diff.as_secs() as _,
63 tv_usec: diff.subsec_micros() as _,
64 }
65 });
66
67 unsafe {
68 from_glib_full(ffi::gdk_pixbuf_animation_get_iter(
69 self.as_ref().to_glib_none().0,
70 start_time
71 .as_ref()
72 .map(|t| t as *const glib::ffi::GTimeVal)
73 .unwrap_or(ptr::null()),
74 ))
75 }
76 }
77}
78
79impl<O: IsA<PixbufAnimation>> PixbufAnimationExtManual for O {}