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
161
162

//! The `BorderedRectangle` widget and related items.

use {
    Color,
    Colorable,
    Dimensions,
    Borderable,
    Point,
    Positionable,
    Rect,
    Scalar,
    Sizeable,
    Widget,
};
use widget;
use widget::triangles::Triangle;


/// A filled rectangle widget that may or may not have some border.
///
/// NOTE: BorderedRectangle is currently implemented as two filled rectangles:
///
/// 1. A `Rectangle` for the border.
/// 2. A `Rectangle` for the non-border area.
///
/// This is flawed in that, if a user specifies an alpha lower than 1.0, the front `Rectangle` will
/// blend with the border `Rectangle`, which is likely unexpected behaviour. This should be changed
/// so that the border is drawn using a outlined `Rectangle`.
#[derive(Copy, Clone, Debug, WidgetCommon_)]
pub struct BorderedRectangle {
    /// Data necessary and common for all widget builder types.
    #[conrod(common_builder)]
    pub common: widget::CommonBuilder,
    /// Unique styling for the **BorderedRectangle**.
    pub style: Style,
}

widget_ids! {
    struct Ids {
        border,
        rectangle,
    }
}

/// Unique styling for the **BorderedRectangle** widget.
#[derive(Copy, Clone, Debug, Default, PartialEq, WidgetStyle_)]
pub struct Style {
    /// Shape styling for the inner rectangle.
    #[conrod(default = "theme.shape_color")]
    pub color: Option<Color>,
    /// The thickness of the border.
    #[conrod(default = "theme.border_width")]
    pub border: Option<Scalar>,
    /// The color of the border.
    #[conrod(default = "theme.border_color")]
    pub border_color: Option<Color>,
}

/// Unique state for the `BorderedRectangle`.
pub struct State {
    ids: Ids,
}

impl BorderedRectangle {

    /// Build a new **BorderedRectangle**.
    pub fn new(dim: Dimensions) -> Self {
        BorderedRectangle {
            common: widget::CommonBuilder::default(),
            style: Style::default(),
        }.wh(dim)
    }

    builder_method!(pub with_style { style = Style });

}


impl Widget for BorderedRectangle {
    type State = State;
    type Style = Style;
    type Event = ();

    fn init_state(&self, id_gen: widget::id::Generator) -> Self::State {
        State {
            ids: Ids::new(id_gen),
        }
    }

    fn style(&self) -> Self::Style {
        self.style.clone()
    }

    /// Update the state of the Rectangle.
    fn update(self, args: widget::UpdateArgs<Self>) -> Self::Event {
        let widget::UpdateArgs { id, state, style, rect, ui, .. } = args;

        let border = style.border(&ui.theme);
        if let Some(triangles) = border_triangles(rect, border) {
            let border_color = style.border_color(&ui.theme);
            widget::Triangles::single_color(border_color, triangles.iter().cloned())
                .with_bounding_rect(rect)
                .parent(id)
                .graphics_for(id)
                .set(state.ids.border, ui);
        }

        let color = style.color(&ui.theme);
        widget::Rectangle::fill(rect.pad(border).dim())
            .xy(rect.xy())
            .color(color)
            .parent(id)
            .graphics_for(id)
            .set(state.ids.rectangle, ui);
    }

}


impl Colorable for BorderedRectangle {
    builder_method!(color { style.color = Some(Color) });
}


impl Borderable for BorderedRectangle {
    builder_methods!{
        border { style.border = Some(Scalar) }
        border_color { style.border_color = Some(Color) }
    }
}


/// The eight triangles that describe a rectangular border.
///
/// `rect` specifies the outer rectangle and `border` specifies the thickness of the border.
///
/// Returns `None` if `border` is less than or equal to `0`.
pub fn border_triangles(rect: Rect, border: Scalar) -> Option<[Triangle<Point>; 8]> {
    if border <= 0.0 {
        return None;
    }

    // Pad the edges so that the line does not exceed the bounding rect.
    let (l, r, b, t) = rect.l_r_b_t();
    let l_pad = l + border;
    let r_pad = r - border;
    let b_pad = b + border;
    let t_pad = t - border;

    // The four quads that make up the border.
    let r1 = [[l, t], [r_pad, t], [r_pad, t_pad], [l, t_pad]];
    let r2 = [[r_pad, t], [r, t], [r, b_pad], [r_pad, b_pad]];
    let r3 = [[l_pad, b_pad], [r, b_pad], [r, b], [l_pad, b]];
    let r4 = [[l, t_pad], [l_pad, t_pad], [l_pad, b], [l, b]];

    let (r1a, r1b) = widget::triangles::from_quad(r1);
    let (r2a, r2b) = widget::triangles::from_quad(r2);
    let (r3a, r3b) = widget::triangles::from_quad(r3);
    let (r4a, r4b) = widget::triangles::from_quad(r4);

    Some([r1a, r1b, r2a, r2b, r3a, r3b, r4a, r4b])
}