Make FPS rate configurable, minor cleanup

src/main.rs

@@ -25,6 +25,9 @@ const DEFAULT_THREAD_COUNT: usize = 4;
 const DEFAULT_IMAGE_WIDTH: u32 = 1920;
 const DEFAULT_IMAGE_HEIGHT: u32 = 1080;
 
+// The default frames per second rate
+const DEFAULT_IMAGE_FPS: u32 = 1;
+
 // The amount of milliseconds to wait for an image, when a painter has no image.
 const PAINTER_IMAGE_WAIT_DELAY_MILLIS: u64 = 100;
 
@@ -80,10 +83,18 @@ fn main() {
         .parse::<u32>()
         .expect("Invalid Y offset");
 
+    // Get the FPS rate
+    let fps = matches
+        .value_of("fps")
+        .unwrap_or(&format!("{}", DEFAULT_IMAGE_FPS))
+        .parse::<u32>()
+        .expect("Invalid frames per second rate");
+
     // Start
     start(
         host,
         image_paths,
+        fps,
         count,
         (width, height),
         (offset_x, offset_y)
@@ -139,6 +150,12 @@ fn parse_args<'a>() -> ArgMatches<'a> {
 			.value_name("PIXELS")
 			.help("Drawing Y offset in pixels (def: 0)")
 			.takes_value(true))
+		.arg(Arg::with_name("fps")
+			.short("r")
+			.long("fps")
+			.value_name("RATE")
+			.help("Frames per second with multiple images (def: 1)")
+			.takes_value(true))
 		.get_matches()
 }
 
@@ -146,6 +163,7 @@ fn parse_args<'a>() -> ArgMatches<'a> {
 fn start(
     host: &str,
     image_paths: Vec<&str>,
+    fps: u32,
     count: usize,
     size: (u32, u32),
     offset: (u32, u32)
@@ -166,7 +184,11 @@ fn start(
         image_manager.tick(&mut canvas);
 
         // Sleep until we need to show the next image
-        thread::sleep(Duration::new(1, 0));
+        thread::sleep(
+            Duration::from_millis(
+                (1000f32 / (fps as f32)) as u64
+            )
+        );
     }
 }