src: rewrite display to have generic surface implementations

src/embedded_graphics_lib.rs

@@ -3,23 +3,40 @@ use embedded_graphics::{
     pixelcolor::Rgb888,
     primitives::Rectangle
 };
+use embedded_graphics::pixelcolor::RgbColor;
 use ws2812_esp32_rmt_driver::lib_embedded_graphics::{Ws2812DrawTarget, LedPixelShape};
 
-use std::rc::Rc;
-use std::cell::RefCell;
-use std::sync::{Arc, Mutex};
 use running_average::RealTimeRunningAverage;
+use std::io;
 
 use crate::power;
+use crate::power::AsMilliwatts;
 use crate::lib8::*;
 use crate::render::*;
 use crate::time::Periodically;
+use crate::task::Task;
 use crate::geometry::*;
 
-pub struct EmbeddedDisplay<T>
+impl<T: RgbColor> AsMilliwatts for T {
+    fn as_milliwatts(&self) -> u32 {
+        const RED_MW : u32   = 16 * 5; //< 16mA @ 5v = 80mW
+        const GREEN_MW : u32 = 11 * 5; //< 11mA @ 5v = 55mW
+        const BLUE_MW : u32  = 15 * 5; //< 15mA @ 5v = 75mW
+        const DARK_MW : u32  =  1 * 5; //<  1mA @ 5v =  5mW
+
+        let red = (self.r() as u32 * RED_MW).wrapping_shr(8);
+        let green = (self.g() as u32 * GREEN_MW).wrapping_shr(8);
+        let blue = (self.b() as u32 * BLUE_MW).wrapping_shr(8);
+
+        return red + green + blue + DARK_MW;
+    }
+}
+
+pub struct EmbeddedDisplay<T, S>
 where
-T: DrawTarget {
-    surfaces : RefCell<Vec<Surface>>,
+T: DrawTarget,
+S: Surface + Default + Clone {
+    surfaces : SurfacePool<S>,
     target: T,
     total_mw: u32,
     max_mw: u32,
@@ -28,12 +45,27 @@ T: DrawTarget {
     fps_display: Periodically
 }
 
-impl<T> EmbeddedDisplay<T>
+impl<T: LedPixelShape, S: Surface + Default + Clone> Task for EmbeddedDisplay<Ws2812DrawTarget<'_, T>, S> {
+    fn start(&mut self) {
+        self.target.set_brightness(0);
+    }
+
+    fn name(&self) -> &'static str { "Renderer" }
+
+    fn tick(&mut self) {
+        self.start_frame();
+        self.render_frame();
+        self.end_frame();
+    }
+}
+
+impl<T, S> EmbeddedDisplay<T, S>
 where
-T: DrawTarget {
+T: DrawTarget,
+S: Surface + Default + Clone {
     pub fn new(target: T, max_mw: u32) -> Self {
         EmbeddedDisplay {
-            surfaces: RefCell::new(Vec::new()),
+            surfaces: SurfacePool::new(),
             target: target,
             max_mw: max_mw,
             total_mw: 0,
@@ -44,17 +76,17 @@ T: DrawTarget {
     }
 }
 
-impl<T> Surfaces for EmbeddedDisplay<T>
+impl<T, S> Surfaces<S> for EmbeddedDisplay<T, S>
 where
-T: DrawTarget {
-    fn new_surface(&mut self) -> Surface {
-        let surface = Surface::new();
-        self.surfaces.borrow_mut().push(surface.clone());
-        return surface;
+T: DrawTarget,
+S: Surface + Default + Clone {
+    fn new_surface(&mut self) -> Result<S, io::Error> {
+        self.surfaces.new_surface()
     }
 }
 
-impl<T: LedPixelShape> Display for EmbeddedDisplay<Ws2812DrawTarget<'_, T>> {
+impl<T: LedPixelShape, S: Surface + Default + Clone> Display<S> for EmbeddedDisplay<Ws2812DrawTarget<'_, T>, S> {
+
     fn start_frame(&mut self) {
         self.total_mw = 0;
         self.frame = self.frame.wrapping_add(1);
@@ -76,19 +108,17 @@ impl<T: LedPixelShape> Display for EmbeddedDisplay<Ws2812DrawTarget<'_, T>> {
         let yStride: u8 = 255 / (size.height as u8);
         let area = Rectangle::new(Point::new(0, 0), size);
 
-        let surfaces = self.surfaces.borrow();
-
         self.target.draw_iter(
             area.points()
             .map(|pos| {
                 let virtCoords = VirtualCoordinates::new(pos.x as u8 * xStride, pos.y as u8 * yStride);
                 let mut pixel = RGB8::new(0, 0, 0);
-                for surface in surfaces.iter() {
+                for surface in self.surfaces.iter() {
                     surface.with_shader(|shader| {
                         pixel = shader.draw(virtCoords.clone());
                     })
                 }
-                self.total_mw += power::color_to_mw(&pixel);
+                self.total_mw += pixel.as_milliwatts();
                 return Pixel(pos, Rgb888::new(pixel.red, pixel.green, pixel.blue));
             })
         ).unwrap();

src/main.rs

@@ -1,13 +1,12 @@
 #![feature(trait_upcasting)]
 #![allow(arithmetic_overflow)]
 use esp_idf_svc::hal::prelude::Peripherals;
-use ws2812_esp32_rmt_driver::lib_embedded_graphics::{LedPixelStrip, LedPixelShape, LedPixelMatrix, Ws2812DrawTarget};
+use ws2812_esp32_rmt_driver::lib_embedded_graphics::{LedPixelShape, Ws2812DrawTarget};
 use embedded_graphics::{
     prelude::*,
 };
 use palette::Hsv;
 use palette::convert::IntoColorUnclamped;
-use std::thread;
 
 mod power;
 mod lib8;
@@ -20,10 +19,11 @@ mod embedded_graphics_lib;
 use crate::time::Periodically;
 use crate::geometry::{Coordinates, VirtualCoordinates};
 use crate::embedded_graphics_lib::EmbeddedDisplay;
+use crate::render::{Surfaces, Surface, SimpleSurface};
 
-struct IdleTask {
+struct IdleTask<T: Surface> {
     frame: u8,
-    surface: render::Surface,
+    surface: T,
     updater: Periodically
 }
 
@@ -37,17 +37,17 @@ impl render::Shader for IdleShader {
     }
 }
 
-impl IdleTask {
-    fn new(render: &mut dyn render::Display) -> Self {
+impl<T: Surface> IdleTask<T> {
+    fn new(surface: T) -> Self {
         IdleTask {
             frame: 0,
-            surface: render.new_surface(),
+            surface: surface,
             updater: Periodically::new_every_n_ms(16)
         }
     }
 }
 
-impl task::Task for IdleTask {
+impl<T: Surface> task::Task for IdleTask<T> {
     fn name(&self) -> &'static str { "Idle" }
 
     fn tick(&mut self) {
@@ -82,6 +82,8 @@ impl LedPixelShape for PonderjarMatrix {
     }
 }
 
+type PonderjarTarget<'a> = Ws2812DrawTarget<'a, PonderjarMatrix>;
+
 fn main() {
     // It is necessary to call this function once. Otherwise some patches to the runtime
     // implemented by esp-idf-sys might not link properly. See https://github.com/esp-rs/esp-idf-template/issues/71
@@ -96,19 +98,17 @@ fn main() {
     let led_pin = peripherals.pins.gpio14;
     let channel = peripherals.rmt.channel0;
 
-    const NUM_PIXELS : usize = 255;
     const POWER_VOLTS : u32 = 5;
     const POWER_MA : u32 = 500;
     const MAX_POWER_MW : u32 = POWER_VOLTS * POWER_MA;
 
     log::info!("Setting up display");
-    let mut target = Ws2812DrawTarget::<PonderjarMatrix>::new(channel, led_pin).unwrap();
-    target.set_brightness(0);
-    let mut display = EmbeddedDisplay::new(target, MAX_POWER_MW);
+    let target = PonderjarTarget::new(channel, led_pin).unwrap();
+    let mut display = EmbeddedDisplay::<PonderjarTarget, SimpleSurface>::new(target, MAX_POWER_MW);
 
     log::info!("Creating runner");
     let mut runner = task::Scheduler::new(vec![
-        Box::new(IdleTask::new(&mut display)),
+        Box::new(IdleTask::new(display.new_surface().unwrap())),
         Box::new(display),
     ]);
 

src/power.rs

@@ -1,16 +1,5 @@
-use embedded_graphics::pixelcolor::RgbColor;
-
-pub fn color_to_mw<T: RgbColor>(color : &T) -> u32 {
-    const RED_MW : u32   = 16 * 5; //< 16mA @ 5v = 80mW
-    const GREEN_MW : u32 = 11 * 5; //< 11mA @ 5v = 55mW
-    const BLUE_MW : u32  = 15 * 5; //< 15mA @ 5v = 75mW
-    const DARK_MW : u32  =  1 * 5; //<  1mA @ 5v =  5mW
-
-    let red = (color.r() as u32 * RED_MW).wrapping_shr(8);
-    let green = (color.g() as u32 * GREEN_MW).wrapping_shr(8);
-    let blue = (color.b() as u32 * BLUE_MW).wrapping_shr(8);
-
-    return red + green + blue + DARK_MW;
+pub trait AsMilliwatts {
+    fn as_milliwatts(&self) -> u32;
 }
 
 pub fn brightness_for_mw(total_mw : u32, target : u8, max_power: u32) -> u8 {

src/render.rs

@@ -1,55 +1,47 @@
 use std::rc::Rc;
 use std::cell::RefCell;
 use std::sync::{Arc, Mutex};
-use palette::blend::{BlendWith, Equations, Parameter, PreAlpha};
+use std::io;
 
-use crate::task;
 use crate::lib8::RGB8;
-use crate::power;
-use crate::time::Periodically;
 use crate::geometry::*;
 
-use std::time::Instant;
-
 pub trait Shader: Send {
     fn draw(&self, surface_coords: VirtualCoordinates) -> RGB8;
 }
 
-pub trait Surfaces {
-    fn new_surface(&mut self) -> Surface;
+pub trait Surface {
+    fn with_shader<F: FnMut(&dyn Shader)>(&self, f: F);
+    fn set_shader(&mut self, shader: Box<dyn Shader>);
+    fn clear_shader(&mut self);
+    fn set_opacity(&mut self, opacity: u8);
 }
 
-pub trait Display: Surfaces {
+pub trait Surfaces<T: Surface> {
+    fn new_surface(&mut self) -> Result<T, io::Error>;
+}
+
+pub trait Display<T: Surface>: Surfaces<T> {
     fn start_frame(&mut self) {}
     fn end_frame(&mut self) {}
-
-    fn render_frame(&mut self) {}
+    fn render_frame(&mut self);
 }
 
-impl<T> task::Task for T
-where
-T: Display {
-    fn name(&self) -> &'static str { "Renderer" }
-
-    fn tick(&mut self) {
-        self.start_frame();
-        self.render_frame();
-        self.end_frame();
-    }
-}
-
-struct ShaderBinding {
+pub struct ShaderBinding {
     shader: Option<Box<dyn Shader>>,
     opacity: u8,
 }
 
 #[derive(Clone)]
-pub struct Surface {
-    pub binding: Arc<Mutex<ShaderBinding>>
+pub struct BoundSurface<T> {
+    pub binding: T
 }
 
-impl Surface {
-    pub fn new() -> Self {
+pub type SharedSurface = BoundSurface<Arc<Mutex<ShaderBinding>>>;
+pub type SimpleSurface = BoundSurface<Rc<RefCell<ShaderBinding>>>;
+
+impl Default for BoundSurface<Arc<Mutex<ShaderBinding>>> {
+    fn default() -> Self {
         Self {
             binding: Arc::new(Mutex::new(ShaderBinding {
                 shader: None,
@@ -57,22 +49,79 @@ impl Surface {
             })),
         }
     }
+}
 
-    pub fn with_shader<F: FnOnce(&dyn Shader)>(&self, f: F) {
+impl Default for BoundSurface<Rc<RefCell<ShaderBinding>>>{
+    fn default() -> Self {
+        Self {
+            binding: Rc::new(RefCell::new(ShaderBinding {
+                shader: None,
+                opacity: 255,
+            })),
+        }
+    }
+}
+
+impl Surface for BoundSurface<Rc<RefCell<ShaderBinding>>> {
+    fn with_shader<F: FnMut(&dyn Shader)>(&self, mut f: F) {
+        if let Some(ref shader) = self.binding.borrow().shader {
+            f(shader.as_ref());
+        }
+    }
+
+    fn set_shader(&mut self, shader: Box<dyn Shader>) {
+        self.binding.borrow_mut().shader = Some(shader);
+    }
+
+    fn clear_shader(&mut self) {
+        self.binding.borrow_mut().shader = None;
+    }
+
+    fn set_opacity(&mut self, opacity: u8) {
+        self.binding.borrow_mut().opacity = opacity;
+    }
+}
+
+impl Surface for BoundSurface<Arc<Mutex<ShaderBinding>>> {
+    fn with_shader<F: FnMut(&dyn Shader)>(&self, mut f: F) {
         if let Some(ref shader) = self.binding.lock().unwrap().shader {
             f(shader.as_ref());
         }
     }
 
-    pub fn set_shader(&mut self, shader: Box<dyn Shader>) {
+    fn set_shader(&mut self, shader: Box<dyn Shader>) {
         self.binding.lock().unwrap().shader = Some(shader);
     }
 
-    pub fn clear_shader(&mut self) {
+    fn clear_shader(&mut self) {
         self.binding.lock().unwrap().shader = None;
     }
 
-    pub fn set_opacity(&mut self, opacity: u8) {
+    fn set_opacity(&mut self, opacity: u8) {
         self.binding.lock().unwrap().opacity = opacity;
     }
 }
+
+pub struct SurfacePool<S: Surface + Default> {
+    surfaces: Vec<S>
+}
+
+impl<S: Surface + Default> SurfacePool<S> {
+    pub const fn new() -> Self {
+        Self {
+            surfaces: Vec::new()
+        }
+    }
+
+    pub fn iter(&self) -> std::slice::Iter<S> {
+        self.surfaces.iter()
+    }
+}
+
+impl<S: Surface + Default + Clone> Surfaces<S> for SurfacePool<S> {
+    fn new_surface(&mut self) -> Result<S, io::Error> {
+        let surface = S::default();
+        self.surfaces.push(surface.clone());
+        return Ok(surface);
+    }
+}