add screenshotting

src/main.rs

@@ -1,13 +1,16 @@
 #![feature(random)]
 use core::f32;
 use std::{
-    fs::read_dir,
+    fs::{read_dir, OpenOptions},
+    io::Write,
     path::PathBuf,
+    process::{Command, Stdio},
     sync::mpsc::{self, Receiver, Sender},
     thread::{self, JoinHandle},
-    time::Duration,
+    time::{Duration, SystemTime},
 };
 
+use chrono::{Datelike, Local, Timelike};
 use macroquad::prelude::*;
 
 const THICKNESS: f32 = 2.0;
@@ -19,10 +22,15 @@ static mut PORT: Option<String> = None;
 struct Point {
     x: f32,
     y: f32,
+    time_since_last: f32,
 }
 impl Point {
-    fn new(x: f32, y: f32) -> Self {
-        Self { x, y }
+    fn new(x: f32, y: f32, delta: f32) -> Self {
+        Self {
+            x,
+            y,
+            time_since_last: delta,
+        }
     }
 }
 
@@ -103,7 +111,7 @@ impl<'a> Graph<'a> {
         Self {
             font,
             // start all the dots off screen
-            points: [Point::new(-1., -1.); TAIL_LEN],
+            points: [Point::new(-1., -1., 0.); TAIL_LEN],
             head: 0,
             axises,
             x_origin: x_offset,
@@ -176,6 +184,7 @@ impl<'a> Graph<'a> {
                 self.push(Point::new(
                     self.head_tracker,
                     self.y_origin - y_displacement,
+                    delta_time,
                 ));
             }
             Axis::Two => {
@@ -183,6 +192,7 @@ impl<'a> Graph<'a> {
                 self.push(Point::new(
                     self.x_origin + x_displacement,
                     self.y_origin - y_displacement,
+                    delta_time,
                 ))
             }
         }
@@ -339,12 +349,55 @@ async fn main() {
 
         graph.draw();
 
-        if is_key_pressed(KeyCode::F3) {
-            show_debug = !show_debug;
-        }
         if is_key_pressed(KeyCode::F1) {
             pause = !pause;
         }
+        if is_key_pressed(KeyCode::F2) {
+            // Dump data to csv
+            if let Ok(mut file) = OpenOptions::new()
+                .write(true)
+                .append(false)
+                .truncate(true)
+                .create(true)
+                .open("data.csv")
+            {
+                let mut x = 0.;
+                for p in &graph.points {
+                    x += p.time_since_last;
+                    let _ = file.write_all(format!("{x},{}\n", p.y).as_bytes());
+                }
+                let _ = file.flush();
+
+                let now = Local::now();
+                let date_string = format!(
+                    "{}-{}-{}-{}-{}-{}-{}",
+                    now.year(),
+                    now.month(),
+                    now.day(),
+                    now.hour(),
+                    now.minute(),
+                    now.second(),
+                    now.timestamp_subsec_millis()
+                );
+
+                if let Ok(out_file) = OpenOptions::new()
+                    .write(true)
+                    .append(false)
+                    .truncate(true)
+                    .create(true)
+                    .open(format!("dump-{date_string}.png"))
+                {
+                    let _ = Command::new("gnuplot")
+                        .stdin(file)
+                        .arg("template.gnuplot")
+                        .stdout(out_file)
+                        .spawn();
+                }
+            }
+        }
+        if is_key_pressed(KeyCode::F3) {
+            show_debug = !show_debug;
+        }
 
         let (_, my) = mouse_wheel();
         graph.px_per_s += 10. * my;