Add mpsc to send data to waterfall

src/app.rs

@@ -1,11 +1,25 @@
 use eframe::{egui_glow, glow};
 use egui::mutex::Mutex;
+use std::sync::mpsc;
 use std::sync::Arc;
 
 mod waterfall;
 use waterfall::Waterfall;
 pub mod turbo_colormap;
 
+mod deadbeef_rand {
+    static mut RNG_SEED: u32 = 0x3d2faba7;
+    static mut RNG_BEEF: u32 = 0xdeadbeef;
+    pub fn rand() -> u8 {
+        unsafe {
+            RNG_SEED = (RNG_SEED << 7) ^ ((RNG_SEED >> 25).wrapping_add(RNG_BEEF));
+            RNG_BEEF = (RNG_BEEF << 7) ^ ((RNG_BEEF >> 25).wrapping_add(0xdeadbeef));
+            (RNG_SEED & 0xff) as u8
+        }
+    }
+}
+use deadbeef_rand::rand;
+
 /// We derive Deserialize/Serialize so we can persist app state on shutdown.
 pub struct TemplateApp {
     // Example stuff:
@@ -13,6 +27,7 @@ pub struct TemplateApp {
     value: f32,
     /// Behind an `Arc<Mutex<…>>` so we can pass it to [`egui::PaintCallback`] and paint later.
     waterfall: Arc<Mutex<Waterfall>>,
+    fft_sender: mpsc::Sender<Vec<u8>>,
 }
 
 impl TemplateApp {
@@ -24,6 +39,7 @@ impl TemplateApp {
         // Load previous app state (if any).
         // Note that you must enable the `persistence` feature for this to work.
 
+        let (tx, rx) = mpsc::channel();
         let gl = cc
             .gl
             .as_ref()
@@ -33,7 +49,8 @@ impl TemplateApp {
             // Example stuff:
             label: "Hello World!".to_owned(),
             value: 2.7,
-            waterfall: Arc::new(Mutex::new(Waterfall::new(gl, 300, 300))),
+            waterfall: Arc::new(Mutex::new(Waterfall::new(gl, 300, 300, rx))),
+            fft_sender: tx,
         }
     }
 }
@@ -104,6 +121,12 @@ impl eframe::App for TemplateApp {
 
                 let _angle = response.drag_motion().x * 0.01;
 
+                let mut new_data = vec![0_u8; 300];
+                for data in new_data.iter_mut() {
+                    *data = rand();
+                }
+                self.fft_sender.send(new_data).unwrap();
+
                 // Clone locals so we can move them into the paint callback:
                 let waterfall = self.waterfall.clone();
 

src/app/waterfall.rs

@@ -3,6 +3,7 @@ use glow::HasContext as _;
 use glow::{NEAREST, TEXTURE_2D, TEXTURE_MAG_FILTER, TEXTURE_MIN_FILTER};
 use log;
 use std::mem::{size_of, transmute};
+use std::sync::mpsc::Receiver;
 
 const SIZE_OF_F32: i32 = size_of::<f32>() as i32;
 
@@ -15,19 +16,6 @@ unsafe fn check_for_gl_errors(gl: &glow::Context, msg: &str) {
     }
 }
 
-mod deadbeef_rand {
-    static mut RNG_SEED: u32 = 0x3d2faba7;
-    static mut RNG_BEEF: u32 = 0xdeadbeef;
-    pub fn rand() -> u8 {
-        unsafe {
-            RNG_SEED = (RNG_SEED << 7) ^ ((RNG_SEED >> 25).wrapping_add(RNG_BEEF));
-            RNG_BEEF = (RNG_BEEF << 7) ^ ((RNG_BEEF >> 25).wrapping_add(0xdeadbeef));
-            (RNG_SEED & 0xff) as u8
-        }
-    }
-}
-use deadbeef_rand::rand;
-
 use crate::app::turbo_colormap;
 
 pub struct Waterfall {
@@ -38,6 +26,8 @@ pub struct Waterfall {
     vbo: glow::Buffer,
     ebo: glow::Buffer,
     offset: usize,
+    width: usize,
+    fft_in: Receiver<Vec<u8>>,
 }
 
 impl Waterfall {
@@ -54,11 +44,6 @@ impl Waterfall {
     pub fn paint(&mut self, gl: &glow::Context, _angle: f32) {
         use glow::HasContext as _;
 
-        let mut new_data: [u8; 300] = [0; 300];
-        for data in new_data.iter_mut() {
-            *data = rand();
-        }
-
         unsafe {
             // Bind our texturs
             gl.active_texture(TEXTURE1);
@@ -80,22 +65,27 @@ impl Waterfall {
             check_for_gl_errors(&gl, "bind vao");
 
             // Update texture
-            gl.tex_sub_image_2d(
+            while let Ok(fft) = self.fft_in.try_recv() {
-                glow::TEXTURE_2D,
+                if fft.len() != self.width {
-                0,
+                    todo!();
-                0,
+                }
-                self.offset as i32,
+                gl.tex_sub_image_2d(
-                300,
+                    glow::TEXTURE_2D,
-                1,
+                    0,
-                glow::RED,
+                    0,
-                glow::UNSIGNED_BYTE,
+                    self.offset as i32,
-                PixelUnpackData::Slice(&new_data),
+                    self.width as i32,
-            );
+                    1,
-            check_for_gl_errors(&gl, "update texture");
+                    glow::RED,
-            self.offset = (self.offset + 1) % 300;
+                    glow::UNSIGNED_BYTE,
+                    PixelUnpackData::Slice(&fft),
+                );
+                check_for_gl_errors(&gl, "update texture");
+                self.offset = (self.offset + 1) % self.width;
+            }
 
             if let Some(uniform) = gl.get_uniform_location(self.program, "offset") {
-                gl.uniform_1_f32(Some(&uniform), self.offset as f32 / 300.0);
+                gl.uniform_1_f32(Some(&uniform), self.offset as f32 / self.width as f32);
             }
             check_for_gl_errors(&gl, "update uniform");
 
@@ -106,7 +96,7 @@ impl Waterfall {
             check_for_gl_errors(&gl, "APP PAINT");
         }
     }
-    pub fn new(gl: &glow::Context, width: usize, height: usize) -> Self {
+    pub fn new(gl: &glow::Context, width: usize, height: usize, fft_in: Receiver<Vec<u8>>) -> Self {
         let vertices: [f32; 32] = [
             // positions      // colors          // texture coords
             1.0, 1.0, 0.0, /**/ 1.0, 0.0, 0.0, /**/ 1.0, 1.0, // top right
@@ -320,6 +310,8 @@ impl Waterfall {
                 vbo,
                 ebo,
                 offset: 0_usize,
+                width,
+                fft_in,
             }
         }
     }