cranpose_ui_layout/
constraints.rs

1//! Layout constraints system
2
3/// Constraints used during layout measurement.
4#[derive(Clone, Copy, Debug, PartialEq)]
5pub struct Constraints {
6    pub min_width: f32,
7    pub max_width: f32,
8    pub min_height: f32,
9    pub max_height: f32,
10}
11
12impl Constraints {
13    /// Creates constraints with exact width and height.
14    pub fn tight(width: f32, height: f32) -> Self {
15        Self {
16            min_width: width,
17            max_width: width,
18            min_height: height,
19            max_height: height,
20        }
21    }
22
23    /// Creates constraints with loose bounds (min = 0, max = given values).
24    pub fn loose(max_width: f32, max_height: f32) -> Self {
25        Self {
26            min_width: 0.0,
27            max_width,
28            min_height: 0.0,
29            max_height,
30        }
31    }
32
33    /// Returns true if these constraints have a single size that satisfies them.
34    pub fn is_tight(&self) -> bool {
35        self.min_width == self.max_width && self.min_height == self.max_height
36    }
37
38    /// Returns true if all bounds are finite.
39    pub fn is_bounded(&self) -> bool {
40        self.max_width.is_finite() && self.max_height.is_finite()
41    }
42
43    /// Constrains the provided width and height to fit within these constraints.
44    pub fn constrain(&self, width: f32, height: f32) -> (f32, f32) {
45        (
46            width.clamp(self.min_width, self.max_width),
47            height.clamp(self.min_height, self.max_height),
48        )
49    }
50
51    /// Returns true if the width is bounded (max_width is finite).
52    #[inline]
53    pub fn has_bounded_width(&self) -> bool {
54        self.max_width.is_finite()
55    }
56
57    /// Returns true if the height is bounded (max_height is finite).
58    #[inline]
59    pub fn has_bounded_height(&self) -> bool {
60        self.max_height.is_finite()
61    }
62
63    /// Returns true if both width and height are tight (min == max for both).
64    #[inline]
65    pub fn has_tight_width(&self) -> bool {
66        self.min_width == self.max_width
67    }
68
69    /// Returns true if the height is tight (min == max).
70    #[inline]
71    pub fn has_tight_height(&self) -> bool {
72        self.min_height == self.max_height
73    }
74
75    /// Creates new constraints with tightened width (min = max = given width).
76    pub fn tighten_width(self, width: f32) -> Self {
77        Self {
78            min_width: width,
79            max_width: width,
80            ..self
81        }
82    }
83
84    /// Creates new constraints with tightened height (min = max = given height).
85    pub fn tighten_height(self, height: f32) -> Self {
86        Self {
87            min_height: height,
88            max_height: height,
89            ..self
90        }
91    }
92
93    /// Creates new constraints with the given width bounds.
94    pub fn copy_with_width(self, min_width: f32, max_width: f32) -> Self {
95        Self {
96            min_width,
97            max_width,
98            ..self
99        }
100    }
101
102    /// Creates new constraints with the given height bounds.
103    pub fn copy_with_height(self, min_height: f32, max_height: f32) -> Self {
104        Self {
105            min_height,
106            max_height,
107            ..self
108        }
109    }
110
111    /// Deflates constraints by the given amount on all sides.
112    /// This is useful for applying padding before measuring children.
113    pub fn deflate(self, horizontal: f32, vertical: f32) -> Self {
114        Self {
115            min_width: (self.min_width - horizontal).max(0.0),
116            max_width: (self.max_width - horizontal).max(0.0),
117            min_height: (self.min_height - vertical).max(0.0),
118            max_height: (self.max_height - vertical).max(0.0),
119        }
120    }
121
122    /// Creates new constraints with loosened minimums (min = 0).
123    pub fn loosen(self) -> Self {
124        Self {
125            min_width: 0.0,
126            min_height: 0.0,
127            ..self
128        }
129    }
130
131    /// Creates constraints that enforce the given size.
132    pub fn enforce(self, width: f32, height: f32) -> Self {
133        Self {
134            min_width: width.clamp(self.min_width, self.max_width),
135            max_width: width.clamp(self.min_width, self.max_width),
136            min_height: height.clamp(self.min_height, self.max_height),
137            max_height: height.clamp(self.min_height, self.max_height),
138        }
139    }
140}
cranpose_ui_layout/constraints.rs

cranpose_ui_layout/
constraints.rs
