add graph labels and step resizing on zooming

1 files changed, 58 insertions, 15 deletions

diff --git a/src/ui/graph.rs b/src/ui/graph.rs
index 2f3855d..13e8ac9 100644
--- a/src/ui/graph.rs
+++ b/src/ui/graph.rs
@@ -4,7 +4,7 @@ use super::Message;
 use iced::{
     event,
     mouse::{self, Interaction},
-    widget::canvas::{self, stroke, Cache, Frame, Geometry, LineCap, Path, Stroke},
+    widget::canvas::{self, stroke, Cache, Frame, Geometry, LineCap, Path, Stroke, Text},
     Color, Point, Rectangle, Renderer, Size, Theme, Vector,
 };
 
@@ -45,12 +45,22 @@ pub struct GraphState {
 }
 
 impl GraphState {
-    fn view_rectangle(&self, frame: &Frame) -> Rectangle {
-        let s = Size::new(frame.width() / self.scale + 2.0, frame.height() / self.scale + 2.0);
-        let p = Point::new(-self.center.x / self.scale - s.width / 2.0, -self.center.y / self.scale - s.height / 2.0);
+    fn view_rectangle(&self, frame: &Frame, step: usize) -> Rectangle {
+        let s = Size::new(
+            self.map_to_step(frame.width() / self.scale + 2.0 * step as f32, step),
+            self.map_to_step(frame.height() / self.scale + 2.0 * step as f32, step),
+        );
+        let p = Point::new(
+            self.map_to_step(-self.center.x / self.scale - s.width / 2.0, step),
+            self.map_to_step(-self.center.y / self.scale - s.height / 2.0, step),
+        );
         Rectangle::new(p, s)
     }
 
+    fn map_to_step(&self, n: f32, step: usize) -> f32 {
+        ((n as i64 / step as i64) * step as i64) as f32
+    }
+
     fn map_coords(&self, x: f32, y: f32) -> Point {
         Point::new(x, -y)
     }
@@ -79,37 +89,43 @@ impl canvas::Program<Message, Renderer> for GraphCanvas {
         _cursor: mouse::Cursor,
     ) -> Vec<Geometry> {
         let graph = self.graph.draw(renderer, bounds.size(), |frame| {
+            let zcolor = Color::new(0.27, 0.52, 0.53, 1.0);
+            let lcolor = Color::new(0.49, 0.43, 0.39, 1.0);
+            let gcolor = Color::new(0.8, 0.14, 0.11, 1.0);
+            let step = 10_usize.pow((400.0 / state.scale).log10() as u32);
+
             let unitline_whole = Stroke {
                 width: 1.0,
-                style: stroke::Style::Solid(Color::new(0.5, 0.5, 0.5, 1.0)),
+                style: stroke::Style::Solid(lcolor),
                 line_cap: LineCap::Round,
                 ..Stroke::default()
             };
+
             let zeroline = Stroke {
                 width: 3.0,
-                style: stroke::Style::Solid(Color::new(0.0, 0.0, 0.8, 1.0)),
+                style: stroke::Style::Solid(zcolor),
                 line_cap: LineCap::Round,
                 ..Stroke::default()
             };
 
             let graphline = Stroke {
                 width: 3.0,
-                style: stroke::Style::Solid(Color::new(0.8, 0.0, 0.0, 1.0)),
+                style: stroke::Style::Solid(gcolor),
                 line_cap: LineCap::Round,
                 ..Stroke::default()
             };
 
+            let rect = state.view_rectangle(frame, step);
+            let x_end = (rect.x + rect.width) as i64;
+            let y_end = (rect.y + rect.height) as i64;
+
             frame.translate(Vector {
                 x: frame.center().x + state.center.x,
                 y: frame.center().y + state.center.y,
             });
             frame.scale(state.scale);
 
-            let rect = state.view_rectangle(frame);
-            let x_end = (rect.x + rect.width) as i64;
-            let y_end = (rect.y + rect.height) as i64;
-
-            for y in (rect.y as i64..y_end).step_by(1) {
+            for y in (rect.y as i64..y_end).step_by(step) {
                 let line = Path::line(
                     Point::new(rect.x, y as f32),
                     Point::new(rect.x + rect.width, y as f32),
@@ -117,7 +133,7 @@ impl canvas::Program<Message, Renderer> for GraphCanvas {
                 frame.stroke(&line, unitline_whole.clone());
             }
 
-            for x in (rect.x as i64..x_end).step_by(1) {
+            for x in (rect.x as i64..x_end).step_by(step) {
                 let line = Path::line(
                     Point::new(x as f32, rect.y),
                     Point::new(x as f32, rect.y + rect.height),
@@ -142,8 +158,35 @@ impl canvas::Program<Message, Renderer> for GraphCanvas {
             );
 
             frame.with_save(|frame| {
-                frame.translate(Vector { x: 1.0, y: 0.0 });
-                frame.fill_text("1");
+                for x in (rect.x as i64..x_end).step_by(step) {
+                    let p = Point::new(x as f32, 0.0);
+                    frame.fill(&Path::circle(p, 10.0 / state.scale), zcolor);
+                    frame.fill_text(Text {
+                        content: x.to_string(),
+                        position: p,
+                        horizontal_alignment: iced::alignment::Horizontal::Center,
+                        vertical_alignment: iced::alignment::Vertical::Center,
+                        color: Color::WHITE,
+                        ..Text::default()
+                    });
+                }
+
+                for y in (rect.y as i64..y_end).step_by(step) {
+                    if y == 0 {
+                        continue;
+                    }
+
+                    let p = Point::new(0.0, y as f32);
+                    frame.fill(&Path::circle(p, 10.0 / state.scale), zcolor);
+                    frame.fill_text(Text {
+                        content: (-y).to_string(),
+                        position: p,
+                        horizontal_alignment: iced::alignment::Horizontal::Center,
+                        vertical_alignment: iced::alignment::Vertical::Center,
+                        color: Color::WHITE,
+                        ..Text::default()
+                    });
+                }
             });
 
             let mut y1 = self