plotters/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    /// Specifies the object to be translated from
7    type From;
8
9    /// Translate the guest coordinate to the guest coordinate
10    fn translate(&self, from: &Self::From) -> BackendCoord;
11
12    /// Get the Z-value of current coordinate
13    fn depth(&self, _from: &Self::From) -> i32 {
14        0
15    }
16}
17
18impl<C, T> CoordTranslate for T
19where
20    C: CoordTranslate,
21    T: Deref<Target = C>,
22{
23    type From = C::From;
24    fn translate(&self, from: &Self::From) -> BackendCoord {
25        self.deref().translate(from)
26    }
27}
28
29/// The trait indicates that the coordinate system supports reverse transform
30/// This is useful when we need an interactive plot, thus we need to map the event
31/// from the backend coordinate to the logical coordinate
32pub trait ReverseCoordTranslate: CoordTranslate {
33    /// Reverse translate the coordinate from the drawing coordinate to the
34    /// logic coordinate.
35    /// Note: the return value is an option, because it's possible that the drawing
36    /// coordinate isn't able to be represented in te guest coordinate system
37    fn reverse_translate(&self, input: BackendCoord) -> Option<Self::From>;
38}