From a3529772cd0d9329ed40f34ec9beeae2f767ab05 Mon Sep 17 00:00:00 2001
From: Olivier 'reivilibre <olivier@librepush.net>
Date: Sun, 28 Nov 2021 16:08:52 +0000
Subject: [PATCH] Add vertical axis ticks to graph

---
 Cargo.lock                    | 10 ++++++++++
 bare-metrics-gui/Cargo.toml   |  1 +
 bare-metrics-gui/src/graph.rs | 37 ++++++++++++++++++++++++++++++++---
 3 files changed, 45 insertions(+), 3 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 7d62c7f..285dca1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -124,6 +124,15 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
 
+[[package]]
+name = "axis-ticks"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b8d71f0cd2d8ee5cdf22cc6405287931603f7aa312f6eee0f356320d72f08b1"
+dependencies = [
+ "num-traits",
+]
+
 [[package]]
 name = "backtrace"
 version = "0.3.63"
@@ -154,6 +163,7 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "appdirs",
+ "axis-ticks",
  "bare-metrics-core",
  "bare-metrics-reader",
  "eframe",
diff --git a/bare-metrics-gui/Cargo.toml b/bare-metrics-gui/Cargo.toml
index fe1f156..a8bcb74 100644
--- a/bare-metrics-gui/Cargo.toml
+++ b/bare-metrics-gui/Cargo.toml
@@ -21,3 +21,4 @@ rfd = "0.6.1"
 ron = "0.7.0"
 serde = { version = "1.0.130", features = ["derive"] }
 appdirs = "0.2.0"
+axis-ticks = "0.1.0"
diff --git a/bare-metrics-gui/src/graph.rs b/bare-metrics-gui/src/graph.rs
index 3fd26e4..e4a9af7 100644
--- a/bare-metrics-gui/src/graph.rs
+++ b/bare-metrics-gui/src/graph.rs
@@ -4,7 +4,8 @@ use bare_metrics_core::structures::{
 };
 use bare_metrics_reader::{MetricsLogReader, SeekToken};
 use eframe::egui::{
-    Color32, Frame as EguiFrame, PointerButton, Pos2, Rect, Sense, Stroke, Ui, Vec2,
+    Color32, Frame as EguiFrame, Galley, PointerButton, Pos2, Rect, Sense, Stroke, TextStyle, Ui,
+    Vec2,
 };
 use hdrhistogram::Histogram;
 use log::{debug, error, info};
@@ -762,13 +763,43 @@ impl Graph {
             // let display_transform =
             //     emath::RectTransform::from_to(Rect::from_x_y_ranges(x_axis, y_axis), display_rect);
 
-            let display_transform =
-                GraphTransform::from_ranges_and_display_rect(x_axis, y_axis, display_rect);
+            let display_transform = GraphTransform::from_ranges_and_display_rect(
+                x_axis.clone(),
+                y_axis.clone(),
+                display_rect,
+            );
 
             let stroke = Stroke::new(2.0, Color32::GREEN);
 
             let mut last_point = None;
 
+            let ticks = axis_ticks::ticks(y_axis.start().clone(), y_axis.end().clone(), 10);
+            let tick_stroke = Stroke {
+                width: 0.5,
+                color: Color32::LIGHT_GRAY,
+            };
+            for tick in ticks {
+                let text = ui.fonts().layout_no_wrap(
+                    format!("{}", tick),
+                    TextStyle::Small,
+                    Color32::LIGHT_GRAY,
+                );
+
+                let mut text_rect = text.rect;
+                text_rect.set_center(display_transform * (*x_axis.start(), tick));
+                text_rect.set_left(display_rect.left());
+                ui.painter().line_segment(
+                    [
+                        display_transform * (*x_axis.start(), tick)
+                            + Vec2::new(5.0 + text.rect.width(), 0.0),
+                        display_transform * (*x_axis.end(), tick),
+                    ],
+                    tick_stroke,
+                );
+
+                ui.painter().galley(text_rect.left_top(), text);
+            }
+
             if let Some(scalar) = current_window
                 .counters
                 .get(&metric_id)