plotters_unstable/coord/
translate.rs

1use plotters_backend::BackendCoord;
2use std::ops::Deref;
3
4/// The trait that translates some customized object to the backend coordinate
5pub trait CoordTranslate {
6    type From;
7
8    /// Translate the guest coordinate to the guest coordinate
9    fn translate(&self, from: &Self::From) -> BackendCoord;
10}
11
12impl<C, T> CoordTranslate for T
13where
14    C: CoordTranslate,
15    T: Deref<Target = C>,
16{
17    type From = C::From;
18    fn translate(&self, from: &Self::From) -> BackendCoord {
19        self.deref().translate(from)
20    }
21}
22
23/// The trait indicates that the coordinate system supports reverse transform
24/// This is useful when we need an interactive plot, thus we need to map the event
25/// from the backend coordinate to the logical coordinate
26pub trait ReverseCoordTranslate: CoordTranslate {
27    /// Reverse translate the coordinate from the drawing coordinate to the
28    /// logic coordinate.
29    /// Note: the return value is an option, because it's possible that the drawing
30    /// coordinate isn't able to be represented in te guest coordinate system
31    fn reverse_translate(&self, input: BackendCoord) -> Option<Self::From>;
32}