layout/core/
format.rs

1//! Defines the interfaces for accessing and querying shapes.
2
3use super::{
4    geometry::{Point, Position},
5    style::StyleAttr,
6};
7
8/// This is the trait that all elements that can be arranged need to implement.
9pub trait Visible {
10    /// \return the Position of the shape.
11    fn position(&self) -> Position;
12    /// \return the mutable reference to the Position of the shape.
13    fn position_mut(&mut self) -> &mut Position;
14    /// Return true if the element is a connector.
15    fn is_connector(&self) -> bool;
16    /// Swap the coordinates of the location and size.
17    fn transpose(&mut self);
18    /// Update the size of the shape.
19    fn resize(&mut self);
20}
21/// This is the trait that all elements that can be rendered on a canvas need to
22/// implement.
23pub trait Renderable {
24    /// Render the shape into a canvas.
25    /// If \p debug is set then extra markers will be rendered.
26    fn render(&self, debug: bool, canvas: &mut dyn RenderBackend);
27
28    /// \Return the coordinate for the connection point of an arrow that's
29    /// coming from the direction of \p from.
30    /// The format of the path is (x, y, cx, cy), where cx and cy, are the
31    /// control points of the bezier curve.
32    /// \p force is the magnitude of the edge direction.
33    /// \p port is the optional port name (for named records).
34    fn get_connector_location(
35        &self,
36        from: Point,
37        force: f64,
38        port: &Option<String>,
39    ) -> (Point, Point);
40
41    /// Computes the coordinate for the connection point of an arrow that's
42    /// passing through this edge.
43    /// coming from the direction of \p from.
44    /// \returns the bezier path in the format (x, y, cx, cy), where cx and cy,
45    /// are the control points for the entry path of the bezier curve. The exit
46    /// path is assumed to be the mirror point for the center (first point).
47    /// \p force is the magnitude of the edge direction.
48    /// This works with the get_connector_location method for drawing edges.
49    fn get_passthrough_path(
50        &self,
51        from: Point,
52        to: Point,
53        force: f64,
54    ) -> (Point, Point);
55}
56
57pub type ClipHandle = usize;
58
59/// This is the trait that all rendering backends need to implement.
60pub trait RenderBackend {
61    /// Draw a rectangle. The top-left point of the rectangle is \p xy. The shape
62    /// style (color, edge-width) are passed in \p look. The parameter \p clip
63    /// is an optional clip region (see: create_clip).
64    fn draw_rect(
65        &mut self,
66        xy: Point,
67        size: Point,
68        look: &StyleAttr,
69        properties: Option<String>,
70        clip: Option<ClipHandle>,
71    );
72
73    /// Draw a line between \p start and \p stop.
74    fn draw_line(
75        &mut self,
76        start: Point,
77        stop: Point,
78        look: &StyleAttr,
79        properties: Option<String>,
80    );
81
82    /// Draw an ellipse with the center \p xy, and size \p size.
83    fn draw_circle(
84        &mut self,
85        xy: Point,
86        size: Point,
87        look: &StyleAttr,
88        properties: Option<String>,
89    );
90
91    /// Draw a labe.
92    fn draw_text(&mut self, xy: Point, text: &str, look: &StyleAttr);
93
94    /// Draw an arrow, with a label, with the style parameters in \p look.
95    fn draw_arrow(
96        &mut self,
97        path: &[(Point, Point)],
98        dashed: bool,
99        head: (bool, bool),
100        look: &StyleAttr,
101        properties: Option<String>,
102        text: &str,
103    );
104
105    /// Generate a clip region that shapes can use to create complex shapes.
106    fn create_clip(
107        &mut self,
108        xy: Point,
109        size: Point,
110        rounded_px: usize,
111    ) -> ClipHandle;
112}
layout/core/format.rs

layout/core/
format.rs
