From 3a357553e440c779a9fb5b8a6c513570c77a16ed Mon Sep 17 00:00:00 2001
From: numzero <numzer0@yandex.ru>
Date: Sat, 14 Sep 2024 17:00:40 +0300
Subject: [PATCH] Print usage on misusage

---
 src/bin/mesh/main.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/bin/mesh/main.rs b/src/bin/mesh/main.rs
index 50d78e8..db0281e 100644
--- a/src/bin/mesh/main.rs
+++ b/src/bin/mesh/main.rs
@@ -1,7 +1,7 @@
 use glam::*;
 use refraction::mesh_loader::load_mesh;
 use refraction::mesh_tracer::{trace_to_mesh, Mesh};
-use show_image::{ImageInfo, ImageView, WindowOptions};
+use show_image::{exit, ImageInfo, ImageView, WindowOptions};
 use std::env;
 use std::error::Error;
 use std::f32::consts::PI;
@@ -91,6 +91,10 @@ fn render(mesh: &Mesh, camera: impl Fn(Vec2) -> (Vec3, Vec3)) -> Image {
 #[show_image::main]
 fn main() -> Result<(), Box<dyn Error>> {
 	let args: Vec<String> = env::args().collect();
+	if args.len() != 2 {
+		println!("Usage: {} path/to/model.obj", args[0]);
+		exit(1);
+	}
 	let mesh = {
 		let f = File::open(&args[1])?;
 		let mut f = BufReader::new(f);