From 58c72b24c3d64fc6a79ca17da679b3b77fc21f85 Mon Sep 17 00:00:00 2001
From: Brandon Thomas <echelon@gmail.com>
Date: Sun, 5 Apr 2020 22:46:19 -0400
Subject: [PATCH] smaller critical section, but didn't fix lag

---
 src/main.rs    | 33 ++++++++++++++++++---------------
 src/sensors.rs |  7 +++++--
 2 files changed, 23 insertions(+), 17 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 9130074cdd..d0f27ebf36 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -19,6 +19,7 @@ use std::sync::{Arc, PoisonError, RwLockReadGuard};
 use std::sync::RwLock;
 use std::thread;
 use std::time::Duration;
+use std::sync::Mutex;
 
 use glium::{Display, glutin, Surface};
 use glium::glutin::event::{Event, StartCause};
@@ -52,7 +53,7 @@ pub mod k4a_sys_wrapper;
 pub mod sensors;
 
 pub fn main() {
-  let frame : Arc<RwLock<Option<DynamicImage>>> = Arc::new(RwLock::new(None));
+  let frame : Arc<Mutex<Option<DynamicImage>>> = Arc::new(Mutex::new(None));
   let frame2 = frame.clone();
 
   thread::spawn(move || {
@@ -167,25 +168,27 @@ pub fn main() {
     let mut target = display.draw();
     target.clear_color(0.0, 0.0, 1.0, 1.0);
 
-    let mut texture_frame : Option<Texture2d> = None;
+    let mut dynamic_image : Option<DynamicImage> = None;
 
-    match frame.read() {
-      Ok(lock) => {
-        let frame_image = lock.as_ref();
-
-        match lock.as_ref() {
-          Some(dynamic_image) => {
-            let frame_image = dynamic_image.to_rgba();
-            let frame_dimensions = frame_image.dimensions();
-            let frame_image = glium::texture::RawImage2d::from_raw_rgba_reversed(&frame_image.into_raw(), frame_dimensions);
-            texture_frame = Some(glium::texture::Texture2d::new(&display, frame_image).unwrap());
-          },
-          None => {},
-        }
+    match frame.lock() {
+      Ok(mut lock) => {
+        dynamic_image = lock.take();
       },
       Err(_) => {},
     }
 
+    let mut texture_frame : Option<Texture2d> = None;
+
+    match dynamic_image {
+      Some(image) => {
+        let frame_image = image.to_rgba();
+        let frame_dimensions = frame_image.dimensions();
+        let frame_image = glium::texture::RawImage2d::from_raw_rgba_reversed(&frame_image.into_raw(), frame_dimensions);
+        texture_frame = Some(glium::texture::Texture2d::new(&display, frame_image).unwrap());
+      },
+      None => {},
+    }
+
     let texture_to_use: &Texture2d = texture_frame.as_ref().unwrap_or(&textureB);
 
     let uniforms = uniform! {
diff --git a/src/sensors.rs b/src/sensors.rs
index e5d7c5cc26..77385188da 100644
--- a/src/sensors.rs
+++ b/src/sensors.rs
@@ -5,6 +5,7 @@ use std::os::raw::c_char;
 use std::ptr;
 use std::slice;
 use std::sync::{Arc, PoisonError, RwLockWriteGuard};
+use std::sync::Mutex;
 use std::sync::RwLock;
 use std::thread;
 use std::time::Duration;
@@ -33,7 +34,7 @@ use k4a_sys_wrapper::Device;
 use k4a_sys_wrapper::device_get_installed_count;
 use k4a_sys_wrapper::Image;
 
-pub fn capture_thread(frame: Arc<RwLock<Option<DynamicImage>>>) {
+pub fn capture_thread(frame: Arc<Mutex<Option<DynamicImage>>>) {
   let installed_devices = device_get_installed_count();
   println!("Installed devices: {}", installed_devices);
 
@@ -60,14 +61,16 @@ pub fn capture_thread(frame: Arc<RwLock<Option<DynamicImage>>>) {
         continue; // We didn't grab a frame.
       },
     }
+    println!("Got frame!");
 
     let image = captured_image.unwrap();
 
     let image_image = depth_to_image(&image)
         .expect("depth_to_image should work");
 
-    match frame.write() {
+    match frame.lock() {
       Ok(mut lock) => {
+        println!("Wrote to mutex!");
         *lock = Some(image_image)
       },
       Err(_) => {