blittle 0.5.0

A fast little blitter
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

use glam::{I64Vec2, USizeVec2};
use std::fmt::{Display, Formatter};

macro_rules! clip_top_left {
    ($self:ident, $position:ident, $c:ident) => {{
        $position.$c = if $self.position.$c < 0 {
            0
        } else {
            $self.position.$c.unsigned_abs() as usize
        };
    }};
}

macro_rules! clip_bottom_right {
    ($position:ident, $size:ident, $other:ident, $c:ident) => {{
        if $position.$c + $size.$c > $other.size.$c {
            $size.$c = $other.size.$c - $position.$c;
        }
    }};
}

macro_rules! size {
    ($t:tt) => {
        pub const fn from_size(size: USizeVec2) -> Self {
            Self {
                position: $t::ZERO,
                size,
            }
        }
    };
}

macro_rules! overlaps {
    ($self:ident, $other:ident, $other_w:expr, $other_h:expr) => {{
        $self.position.x <= $other.position.x + $other_w
            && $self.position.x + $other_w > $other.position.x
            && $self.position.y <= $other.position.y + $other_h
            && $self.position.y + $other_h > $other.position.y
    }};
}

/// A rectangle in which the `position` can have negative values.
#[derive(Copy, Clone, Debug, Default)]
#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
pub struct RectI {
    pub position: I64Vec2,
    pub size: USizeVec2,
}

impl RectI {
    size!(I64Vec2);

    pub const fn new(position: I64Vec2, size: USizeVec2) -> Option<Self> {
        if size.x == 0 || size.y == 0 {
            None
        } else {
            Some(Self { position, size })
        }
    }

    pub const fn overlaps(&self, other: &Self) -> bool {
        let other_w = other.size.x.cast_signed() as i64;
        let other_h = other.size.y.cast_signed() as i64;
        overlaps!(self, other, other_w, other_h)
    }

    pub const fn clip(self, other: Self) -> Option<RectU> {
        let other_w = other.size.x.cast_signed() as i64;
        let other_h = other.size.y.cast_signed() as i64;
        // Don't try clipping if there is no overlap.
        if overlaps!(self, other, other_w, other_h) {
            let mut position = USizeVec2::ZERO;
            clip_top_left!(self, position, x);
            clip_top_left!(self, position, y);
            let mut size = self.size;
            clip_bottom_right!(position, size, other, x);
            clip_bottom_right!(position, size, other, y);
            let rect = RectU { position, size };
            if rect.size.x > 0 && rect.size.y > 0 {
                Some(rect)
            } else {
                None
            }
        } else {
            None
        }
    }

    pub const fn into_rectu(self) -> RectU {
        RectU {
            position: USizeVec2 {
                x: self.position.x.cast_unsigned() as usize,
                y: self.position.y.cast_unsigned() as usize,
            },
            size: self.size,
        }
    }
}

impl Display for RectI {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        write!(f, "{}, {}", self.position, self.size)
    }
}

/// A rectangle defined by a position and size.
#[derive(Copy, Clone, Debug, Default)]
#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
pub struct RectU {
    pub position: USizeVec2,
    pub size: USizeVec2,
}

impl RectU {
    size!(USizeVec2);

    pub const fn overlaps(&self, other: &Self) -> bool {
        overlaps!(self, other, other.size.x, other.size.y)
    }

    pub const fn into_recti(self) -> RectI {
        RectI {
            position: I64Vec2 {
                x: self.position.x.cast_signed() as i64,
                y: self.position.y.cast_signed() as i64,
            },
            size: self.size,
        }
    }
}