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

use draw::{self, Drawing};
use draw::properties::{spatial, ColorScalar, Draw, Drawn, IntoDrawn, Primitive, Rgba, SetColor, SetDimensions, SetOrientation, SetPosition};
use draw::properties::spatial::{dimension, orientation, position};
use geom;
use math::{BaseFloat, Vector2};

/// Properties related to drawing an **Ellipse**.
#[derive(Clone, Debug)]
pub struct Ellipse<S = geom::DefaultScalar> {
    spatial: spatial::Properties<S>,
    color: Option<Rgba>,
    resolution: Option<usize>,
}

// Ellipse-specific methods.

impl<S> Ellipse<S>
where
    S: BaseFloat,
{
    /// Specify the width and height of the **Ellipse** via a given **radius**.
    pub fn radius(self, radius: S) -> Self {
        let side = radius * (S::one() + S::one());
        self.w_h(side, side)
    }

    /// The number of sides used to draw the ellipse.
    pub fn resolution(mut self, resolution: usize) -> Self {
        self.resolution = Some(resolution);
        self
    }
}

// Trait implementations.

impl<S> IntoDrawn<S> for Ellipse<S>
where
    S: BaseFloat,
{
    type Vertices = draw::mesh::vertex::IterFromPoint2s<geom::ellipse::TriangleVertices<S>, S>;
    type Indices = geom::ellipse::TriangleIndices;
    fn into_drawn(self, draw: Draw<S>) -> Drawn<S, Self::Vertices, Self::Indices> {
        let Ellipse {
            spatial,
            color,
            resolution,
        } = self;

        // First get the dimensions of the ellipse.
        let (maybe_x, maybe_y, maybe_z) = spatial.dimensions.to_scalars(&draw);
        assert!(
            maybe_z.is_none(),
            "z dimension support for ellipse is unimplemented"
        );

        // TODO: These should probably be adjustable via Theme.
        const DEFAULT_RESOLUTION: usize = 50;
        let default_w = || S::from(100.0).unwrap();
        let default_h = || S::from(100.0).unwrap();
        let w = maybe_x.unwrap_or_else(default_w);
        let h = maybe_y.unwrap_or_else(default_h);
        let rect = geom::Rect::from_wh(Vector2 { x: w, y: h });
        let resolution = resolution.unwrap_or(DEFAULT_RESOLUTION);
        let color = color
            .or_else(|| {
                draw.theme(|theme| {
                    theme
                        .color
                        .primitive
                        .get(&draw::theme::Primitive::Ellipse)
                        .map(|&c| c)
                })
            })
            .unwrap_or(draw.theme(|t| t.color.default));

        // TODO: Optimise this using the Circumference and ellipse indices iterators.
        let ellipse = geom::Ellipse::new(rect, resolution);
        let (points, indices) = ellipse.triangle_indices();
        let vertices = draw::mesh::vertex::IterFromPoint2s::new(points, color);
        (spatial, vertices, indices)
    }
}

impl<S> Default for Ellipse<S> {
    fn default() -> Self {
        let spatial = Default::default();
        let color = Default::default();
        let resolution = Default::default();
        Ellipse {
            spatial,
            color,
            resolution,
        }
    }
}

impl<S> SetOrientation<S> for Ellipse<S> {
    fn properties(&mut self) -> &mut orientation::Properties<S> {
        SetOrientation::properties(&mut self.spatial)
    }
}

impl<S> SetPosition<S> for Ellipse<S> {
    fn properties(&mut self) -> &mut position::Properties<S> {
        SetPosition::properties(&mut self.spatial)
    }
}

impl<S> SetDimensions<S> for Ellipse<S> {
    fn properties(&mut self) -> &mut dimension::Properties<S> {
        SetDimensions::properties(&mut self.spatial)
    }
}

impl<S> SetColor<ColorScalar> for Ellipse<S> {
    fn rgba_mut(&mut self) -> &mut Option<Rgba> {
        SetColor::rgba_mut(&mut self.color)
    }
}

// Primitive conversion.

impl<S> From<Ellipse<S>> for Primitive<S> {
    fn from(prim: Ellipse<S>) -> Self {
        Primitive::Ellipse(prim)
    }
}

impl<S> Into<Option<Ellipse<S>>> for Primitive<S> {
    fn into(self) -> Option<Ellipse<S>> {
        match self {
            Primitive::Ellipse(prim) => Some(prim),
            _ => None,
        }
    }
}

// Drawing methods.

impl<'a, S> Drawing<'a, Ellipse<S>, S>
where
    S: BaseFloat,
{
    /// Specify the width and height of the **Ellipse** via a given **radius**.
    pub fn radius(self, radius: S) -> Self {
        self.map_ty(|ty| ty.radius(radius))
    }

    /// The number of sides used to draw the ellipse.
    pub fn resolution(self, resolution: usize) -> Self {
        self.map_ty(|ty| ty.resolution(resolution))
    }
}