embedded_graphics/primitives/triangle/
points.rs

1use crate::{
2    geometry::{Dimensions, Point},
3    primitives::{
4        common::{Scanline, StrokeOffset},
5        triangle::{scanline_iterator::ScanlineIterator, Triangle},
6    },
7};
8
9/// Iterator over all points inside the triangle.
10#[derive(Clone, Eq, PartialEq, Hash, Debug)]
11#[cfg_attr(feature = "defmt", derive(::defmt::Format))]
12pub struct Points {
13    scanline_iter: ScanlineIterator,
14    current_line: Scanline,
15}
16
17impl Points {
18    pub(in crate::primitives) fn new(triangle: &Triangle) -> Self {
19        let scanline_iter = ScanlineIterator::new(
20            triangle,
21            0,
22            StrokeOffset::None,
23            true,
24            &triangle.bounding_box(),
25        );
26
27        let current_line = Scanline::new_empty(0);
28
29        Self {
30            scanline_iter,
31            current_line,
32        }
33    }
34}
35
36impl Iterator for Points {
37    type Item = Point;
38
39    fn next(&mut self) -> Option<Self::Item> {
40        self.current_line.next().or_else(|| {
41            self.current_line = self.scanline_iter.next()?.0;
42
43            self.current_line.next()
44        })
45    }
46}
47
48#[cfg(test)]
49mod tests {
50    use super::*;
51    use crate::{
52        pixelcolor::BinaryColor,
53        primitives::{PointsIter, Primitive, PrimitiveStyle},
54        transform::Transform,
55        Pixel,
56    };
57
58    #[test]
59    fn points_iter() {
60        let triangle = Triangle::new(Point::new(5, 10), Point::new(15, 20), Point::new(10, 15));
61
62        let styled_points = triangle
63            .clone()
64            .into_styled(PrimitiveStyle::with_fill(BinaryColor::On))
65            .pixels()
66            .map(|Pixel(p, _)| p);
67
68        assert!(triangle.points().eq(styled_points));
69    }
70
71    #[test]
72    fn off_screen_still_draws_points() {
73        let off_screen = Triangle::new(Point::new(10, 10), Point::new(20, 20), Point::new(30, -30));
74        let on_screen = off_screen.translate(Point::new(0, 35));
75
76        assert!(off_screen
77            .points()
78            .eq(on_screen.points().map(|p| p - Point::new(0, 35))));
79    }
80
81    #[test]
82    fn it_draws_unfilled_tri_line_y() {
83        let mut tri = Triangle::new(Point::new(2, 2), Point::new(2, 4), Point::new(2, 4)).points();
84
85        assert_eq!(tri.next(), Some(Point::new(2, 2)));
86        assert_eq!(tri.next(), Some(Point::new(2, 3)));
87        assert_eq!(tri.next(), Some(Point::new(2, 4)));
88        assert_eq!(tri.next(), None);
89    }
90
91    #[test]
92    fn it_draws_unfilled_tri_line_x() {
93        let mut tri = Triangle::new(Point::new(2, 2), Point::new(4, 2), Point::new(4, 2)).points();
94
95        assert_eq!(tri.next(), Some(Point::new(2, 2)));
96        assert_eq!(tri.next(), Some(Point::new(3, 2)));
97        assert_eq!(tri.next(), Some(Point::new(4, 2)));
98        assert_eq!(tri.next(), None);
99    }
100}
embedded_graphics/primitives/triangle/points.rs

embedded_graphics/primitives/triangle/
points.rs
