rvlib/
view.rs

1use image::{GenericImageView, ImageBuffer, Rgb};
2
3use rvimage_domain::{pos_transform, BbF, Calc, PtF, ShapeI, TPtF};
4
5pub type ImageU8 = ImageBuffer<Rgb<u8>, Vec<u8>>;
6
7/// Scales a coordinate from an axis of `size_from` to an axis of `size_to`
8pub fn scale_coord<T>(x: T, size_from: T, size_to: T) -> T
9where
10    T: Calc,
11{
12    x * size_to / size_from
13}
14
15fn coord_view_2_orig(x: TPtF, n_transformed: TPtF, n_orig: TPtF, off: TPtF) -> TPtF {
16    off + scale_coord(x, n_transformed, n_orig)
17}
18
19/// Converts the position of a pixel in the view to the coordinates of the original image
20pub fn pos_2_orig_pos(
21    view_pos: PtF,
22    shape_orig: ShapeI,
23    shape_win: ShapeI,
24    zoom_box: &Option<BbF>,
25) -> PtF {
26    pos_transform(view_pos, shape_orig, shape_win, zoom_box, coord_view_2_orig)
27}
28fn coord_orig_2_view(x: f64, n_transformed: f64, n_orig: f64, off: f64) -> f64 {
29    scale_coord(x - off, n_orig, n_transformed)
30}
31
32/// Converts the position of a pixel in the view to the coordinates of the original image
33pub fn pos_from_orig_pos(
34    orig_pos: PtF,
35    shape_orig: ShapeI,
36    shape_win: ShapeI,
37    zoom_box: &Option<BbF>,
38) -> Option<PtF> {
39    if let Some(zb) = zoom_box {
40        if !zb.contains(orig_pos) {
41            return None;
42        }
43    }
44    Some(pos_transform(
45        orig_pos,
46        shape_orig,
47        shape_win,
48        zoom_box,
49        coord_orig_2_view,
50    ))
51}
52#[must_use]
53pub fn from_orig(im_orig: &ImageU8, zoom_box: Option<BbF>) -> ImageU8 {
54    if let Some(zoom_box) = zoom_box {
55        im_orig
56            .view(
57                zoom_box.x.round() as u32,
58                zoom_box.y.round() as u32,
59                zoom_box.w.round() as u32,
60                zoom_box.h.round() as u32,
61            )
62            .to_image()
63    } else {
64        im_orig.clone()
65    }
66}
67
68#[must_use]
69pub fn project_on_bb(p: PtF, bb: &BbF) -> PtF {
70    let x = p.x.max(bb.x).min(bb.x + bb.w - 1.0);
71    let y = p.y.max(bb.y).min(bb.y + bb.h - 1.0);
72    PtF { x, y }
73}
74
75#[test]
76fn test_project() {
77    let bb = BbF::from_arr(&[5.0, 5.0, 10.0, 10.0]);
78    assert_eq!(
79        PtF { x: 5.0, y: 5.0 },
80        project_on_bb((0.0, 0.0).into(), &bb)
81    );
82    assert_eq!(
83        PtF { x: 14.0, y: 14.0 },
84        project_on_bb((15.0, 20.0).into(), &bb)
85    );
86    assert_eq!(
87        PtF { x: 10.0, y: 14.0 },
88        project_on_bb((10.0, 15.0).into(), &bb)
89    );
90    assert_eq!(
91        PtF { x: 14.0, y: 14.0 },
92        project_on_bb((20.0, 15.0).into(), &bb)
93    );
94}
rvlib/view.rs

rvlib/
view.rs
