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

// Take a look at the license at the top of the repository in the LICENSE file.

use std::fmt;

use glib::translate::from_glib;
use gst::prelude::*;

/// Metadata type that holds information about the positioning, size,
/// transparency and composition operator of a video frame in the timeline
/// composition.
#[repr(transparent)]
#[doc(alias = "GESFrameCompositionMeta")]
pub struct FrameCompositionMeta(ffi::GESFrameCompositionMeta);

unsafe impl Send for FrameCompositionMeta {}

unsafe impl Sync for FrameCompositionMeta {}

impl FrameCompositionMeta {
    #[inline]
    pub fn alpha(&self) -> f64 {
        self.0.alpha
    }

    #[inline]
    pub fn position(&self) -> (f64, f64) {
        (self.0.posx, self.0.posy)
    }

    #[inline]
    pub fn pos_x(&self) -> f64 {
        self.0.posx
    }

    #[inline]
    pub fn pos_y(&self) -> f64 {
        self.0.posy
    }

    #[inline]
    pub fn size(&self) -> (f64, f64) {
        (self.0.width, self.0.height)
    }

    #[inline]
    pub fn width(&self) -> f64 {
        self.0.width
    }

    #[inline]
    pub fn height(&self) -> f64 {
        self.0.height
    }

    #[inline]
    pub fn zorder(&self) -> u32 {
        self.0.zorder
    }

    #[inline]
    pub fn operator(&self) -> i32 {
        self.0.operator
    }
}

unsafe impl MetaAPI for FrameCompositionMeta {
    type GstType = ffi::GESFrameCompositionMeta;

    #[doc(alias = "ges_frame_composition_meta_api_get_type")]
    #[inline]
    fn meta_api() -> glib::Type {
        unsafe { from_glib(ffi::ges_frame_composition_meta_api_get_type()) }
    }
}

impl fmt::Debug for FrameCompositionMeta {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        f.debug_struct("FrameCompositionMeta")
            .field("pos-x", &self.pos_x())
            .field("pos-y", &self.pos_y())
            .field("width", &self.width())
            .field("height", &self.height())
            .field("zorder", &self.zorder())
            .field("alpha", &self.alpha())
            .field("operator", &self.operator())
            .finish()
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    fn add_composition_meta(
        buffer: &mut gst::BufferRef,
        position: (f64, f64),
        size: (f64, f64),
        alpha: f64,
        zorder: u32,
        operator: i32,
    ) -> Result<gst::MetaRefMut<FrameCompositionMeta, gst::meta::Standalone>, glib::BoolError> {
        assert_initialized_main_thread!();

        unsafe {
            let meta = ffi::ges_buffer_add_frame_composition_meta(buffer.as_mut_ptr());

            if meta.is_null() {
                return Err(glib::bool_error!("Failed to add frame composition meta"));
            }

            let mut result = FrameCompositionMeta::from_mut_ptr(buffer, meta);
            result.0.posx = position.0;
            result.0.posy = position.1;
            result.0.width = size.0;
            result.0.height = size.1;
            result.0.alpha = alpha;
            result.0.zorder = zorder;
            result.0.operator = operator;
            Ok(result)
        }
    }

    #[test]
    fn test_add_get_meta() {
        gst::init().unwrap();
        crate::init().unwrap();

        let mut buffer = gst::Buffer::with_size(320 * 240 * 4).unwrap();
        {
            let _meta = add_composition_meta(
                buffer.get_mut().unwrap(),
                (42., 42.),
                (20., 22.),
                0.42,
                2,
                42,
            )
            .unwrap();
        }

        {
            let meta = buffer.meta::<FrameCompositionMeta>().unwrap();
            assert_eq!(meta.position(), (42., 42.));
            assert_eq!(meta.size(), (20., 22.));
            assert_eq!(meta.alpha(), 0.42);
            assert_eq!(meta.zorder(), 2);
            assert_eq!(meta.operator(), 42);
        }
    }
}