tcod 0.15.0

The Rust bindings for the Doryen library (a.k.a. libtcod).
Documentation 
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
151
152
153
154
155
156
157
158
159
160

//! Port of line drawing toolkit.

use bindings::ffi;
use bindings::c_int;

/// tcod-rs uses libtcod's multithreaded line API, therefore more then one line
/// can be created and drawn. The `Line` struct represents a line.
#[derive(Default)]
pub struct Line {
    tcod_line: ffi::TCOD_bresenham_data_t,
}

impl Line {
    /// Creates a line from `start` to `end` (inclusive).
    pub fn new(start: (i32, i32), end: (i32, i32)) -> Self {
        let mut line: Line = Default::default();
        unsafe {
            ffi::TCOD_line_init_mt(start.0, start.1, end.0, end.1, &mut line.tcod_line)
        };
        line
    }

    /// Creates a new line and steps over it using provided closure as a callback.
    /// The stepping is aborted when the closure returns false. The function returs
    /// a part of the line that has not been stepped over.
    ///
    /// # Examples
    ///
    /// ```no_run
    /// # use tcod::line::Line;
    /// let mut line = Line::new_with_callback((1, 1), (5, 5), |x, _y| {
    ///     x < 4
    /// });
    /// assert_eq!(Some((5, 5)), line.next());
    /// ```
    pub fn new_with_callback<F>(start: (i32, i32), end: (i32, i32), callback: F) -> Self
        where F: FnMut(i32, i32) -> bool
    {
        let mut line: Line = Line::new(start, end);
        line.step_with_callback(callback);
        line
    }

    /// You can step through each point of the line. Return `None` when end of line
    /// has been reached.
    pub fn step(&mut self) -> Option<(i32, i32)> {
        let mut x: c_int = 0;
        let mut y: c_int = 0;
        let end = unsafe {
            ffi::TCOD_line_step_mt(&mut x, &mut y, &mut self.tcod_line)
        };

        if end == 0 {
            Some((x, y))
        } else {
            None
        }
    }

    fn step_with_callback<F>(&mut self, mut callback: F) -> bool
        where F: FnMut(i32, i32) -> bool
    {
        let mut x: c_int = self.tcod_line.origx;
        let mut y: c_int = self.tcod_line.origy;
        loop {
		    if !callback(x, y) {
                return false
            }
            let step = unsafe {
                ffi::TCOD_line_step_mt(&mut x, &mut y, &mut self.tcod_line)
            };
            if step != 0 {
                break
            }
	    }
	    true
    }
}

impl Iterator for Line {
    type Item = (i32, i32);

    fn next(&mut self) -> Option<Self::Item> {
        self.step()
    }
}

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

    #[test]
    fn line_created() {
        let line = Line::new((1, 1), (5, 5));

        assert_eq!(line.tcod_line.origx, 1);
        assert_eq!(line.tcod_line.origy, 1);
        assert_eq!(line.tcod_line.destx, 5);
        assert_eq!(line.tcod_line.desty, 5);
    }

    #[test]
    fn start_end_same() {
        let line = Line::new((1, 1), (1, 1));

        assert_eq!(line.tcod_line.origx, 1);
        assert_eq!(line.tcod_line.origy, 1);
        assert_eq!(line.tcod_line.destx, 1);
        assert_eq!(line.tcod_line.desty, 1);
    }

    #[test]
    fn step_line() {
        let mut line = Line::new((1, 1), (5, 5));

        assert_eq!(Some((2, 2)), line.step());
        assert_eq!(Some((3, 3)), line.step());
        assert_eq!(Some((4, 4)), line.step());
        assert_eq!(Some((5, 5)), line.step());
        assert_eq!(None, line.step());
    }

    #[test]
    fn step_two_lines() {
        let mut line1 = Line::new((1, 1), (5, 5));
        let mut line2 = Line::new((10, 10), (14, 14));

        assert_eq!(Some((2, 2)), line1.step());
        assert_eq!(Some((11, 11)), line2.step());
        assert_eq!(Some((3, 3)), line1.step());
        assert_eq!(Some((12, 12)), line2.step());
        assert_eq!(Some((4, 4)), line1.step());
        assert_eq!(Some((13, 13)), line2.step());
        assert_eq!(Some((5, 5)), line1.step());
        assert_eq!(Some((14, 14)), line2.step());
        assert_eq!(None, line1.step());
        assert_eq!(None, line2.step());
    }

    #[test]
    fn iterate_over_line() {
        let mut line = Line::new((1, 1), (5, 5));

        assert_eq!(Some((2, 2)), line.next());
        assert_eq!(Some((3, 3)), line.next());
        assert_eq!(Some((4, 4)), line.next());
        assert_eq!(Some((5, 5)), line.next());
        assert_eq!(None, line.next());
    }

    #[test]
    fn line_with_callback() {
        let mut line = Line::new_with_callback((1, 1), (5, 5), |x, _y| {
            assert!(x <= 4);
            x < 4
        });
        assert_eq!(Some((5, 5)), line.next());
        assert_eq!(None, line.next());
    }
}