Merge pull request #6 from bananaturtlesandwich/main

fix axis label drawing (#5)

src/backend.rs

@@ -1,24 +1,24 @@
 //! Plotter backend for egui
 
 use std::error::Error as ErrorTrait;
+use std::f32::consts::FRAC_PI_2;
 use std::fmt::{Display, Formatter, Result as FmtResult};
 use std::ops::{Add, AddAssign, MulAssign, Sub, SubAssign};
 
 use egui::{
-    epaint::PathShape, Align2, Color32, FontFamily as EguiFontFamily, FontId, Pos2, Rect, Stroke,
-    Ui,
+    epaint::{PathShape, TextShape},
+    Align, Align2, Color32, FontFamily as EguiFontFamily, FontId, Pos2, Rect, Stroke, Ui,
 };
 use plotters_backend::{
+    text_anchor::{HPos, Pos, VPos},
     BackendColor, BackendCoord, BackendStyle, BackendTextStyle, DrawingBackend, DrawingErrorKind,
     FontFamily as PlottersFontFamily,
 };
 
 #[derive(Debug, Clone, Copy)]
 /// Error to be returned by the backend. Since egui doesn't return any errors
 /// on any painter operations, this is a stub type.
-pub enum EguiBackendError {
-    None,
-}
+pub struct EguiBackendError;
 
 impl Display for EguiBackendError {
     #[inline]
@@ -322,7 +322,48 @@ impl<'a> DrawingBackend for EguiBackend<'a> {
 
         let color: Color32 = EguiBackendColor::from(style.color()).into();
 
-        painter.text(pos.into(), Align2::LEFT_TOP, text, font, color);
+        let rotations = style.transform() as usize;
+        let angle = rotations as f32 * FRAC_PI_2;
+
+        let Pos { h_pos, v_pos } = style.anchor();
+
+        // !TODO! Find a slightly more eligant rotation function.
+        let mut anchor = Align2([
+            match h_pos {
+                HPos::Left => Align::LEFT,
+                HPos::Right => Align::RIGHT,
+                HPos::Center => Align::Center,
+            },
+            match v_pos {
+                VPos::Top => Align::TOP,
+                VPos::Center => Align::Center,
+                VPos::Bottom => Align::BOTTOM,
+            },
+        ]);
+        fn rotate(anchor: &mut Align2) {
+            *anchor = match anchor {
+                &mut Align2::LEFT_TOP => Align2::RIGHT_TOP,
+                &mut Align2::RIGHT_TOP => Align2::RIGHT_BOTTOM,
+                &mut Align2::RIGHT_BOTTOM => Align2::LEFT_BOTTOM,
+                &mut Align2::LEFT_BOTTOM => Align2::LEFT_TOP,
+                &mut Align2::LEFT_CENTER => Align2::CENTER_TOP,
+                &mut Align2::CENTER_TOP => Align2::RIGHT_CENTER,
+                &mut Align2::RIGHT_CENTER => Align2::CENTER_BOTTOM,
+                &mut Align2::CENTER_BOTTOM => Align2::LEFT_CENTER,
+                &mut Align2::CENTER_CENTER => Align2::CENTER_CENTER,
+            }
+        }
+        for _ in 0..rotations {
+            rotate(&mut anchor)
+        }
+        let galley = painter.layout_no_wrap(text.to_string(), font, color);
+        let rect = anchor.anchor_rect(Rect::from_min_size(pos.into(), galley.size()));
+        if !galley.is_empty() {
+            painter.add(TextShape {
+                angle,
+                ..TextShape::new(rect.min, galley)
+            });
+        }
 
         Ok(())
     }

src/charts/xytime.rs

@@ -132,8 +132,6 @@ impl XyTimeData {
             ranges.push((range_x, range_y));
         }
 
-        let y_unit: String = y_unit.split("").map(|c| format!("{}\n", c)).collect();
-
         // Turn all the vecs and strings into arcs since they are more or less read-only at
         // this point