render: implement surface mapping api

src/platform/smart_leds_lib.rs

@@ -4,6 +4,7 @@ use crate::lib8::Rgb8Blend;
 use crate::render::{Surface, SurfacePool, Display, Surfaces};
 use crate::power::{brightness_for_mw, AsMilliwatts};
 use crate::geometry::*;
+use crate::mappings::*;
 use std::fmt::{Debug, Formatter};
 
 use smart_leds::brightness;
@@ -13,7 +14,8 @@ use std::io;
 use rgb::Rgb;
 
 pub struct SmartLedDisplay<T: SmartLedsWrite<Color = Rgb<u8>>, S: Surface, const PIXEL_NUM: usize> {
-    surfaces : SurfacePool<S>,
+    surfaces : Option<SurfacePool<S>>,
+    pixmap: StrideMapping,
     target: T,
     pixbuf: [T::Color; PIXEL_NUM],
     max_mw: u32
@@ -31,10 +33,11 @@ impl<T: SmartLedsWrite<Color = Rgb<u8>>, S: Surface, const PIXEL_NUM: usize> Deb
 impl<T: SmartLedsWrite<Color = Rgb<u8>>, S: Surface, const PIXEL_NUM: usize> SmartLedDisplay<T, S, PIXEL_NUM> {
     pub fn new(target: T, max_mw: u32) -> Self {
         SmartLedDisplay {
-            surfaces: SurfacePool::new(),
             pixbuf: [Rgb::new(0, 0, 0); PIXEL_NUM],
+            surfaces: Some(SurfacePool::new()),
             target: target,
             max_mw: max_mw,
+            pixmap: StrideMapping::new()
         }
     }
 }
@@ -49,8 +52,12 @@ impl<T, S, const PIXEL_NUM: usize> Surfaces<S> for SmartLedDisplay<T, S, PIXEL_N
 where
 T: SmartLedsWrite<Color = Rgb<u8>>,
 S: Surface {
-    fn new_surface(&mut self) -> Result<S, io::Error> {
-        self.surfaces.new_surface()
+    fn new_surface(&mut self, area: &Rectangle<u8, Virtual>) -> Result<S, io::Error> {
+        if let Some(ref mut s) = self.surfaces {
+            s.new_surface(area)
+        } else {
+            panic!("Could not grab surface list")
+        }
     }
 }
 
@@ -66,16 +73,21 @@ impl<T: SmartLedsWrite<Color = Rgb<u8>>, S: Surface, const PIXEL_NUM: usize> Dis
     }
 
     fn render_frame(&mut self) {
-        for x in 0..self.pixbuf.len() {
-            let virt_coords = VirtualCoordinates::new(x as u8, 0);
-            let mut pixel = Rgb::new(0, 0, 0);
-            for surface in self.surfaces.iter() {
-                surface.with_shader(|shader| {
-                    pixel = pixel.saturating_add(shader.draw(&virt_coords));
-                })
-            }
-            self.pixbuf[x] = Rgb::new(pixel.r, pixel.g, pixel.b);
-        };
+        let surfaces = self.surfaces.take().unwrap();
+        for surface in surfaces.iter() {
+            let rect = surface.rect().clone();
+            let mut sel = self.pixmap.select(&rect);
+            surface.with_shader(|shader| {
+                while let Some((virt_coords, phys_coords)) = sel.next() {
+                    let idx = phys_coords.x as usize;
+                    if idx >= PIXEL_NUM {
+                        continue;
+                    }
+                    self.pixbuf[idx] = self.pixbuf[idx].saturating_add(shader.draw(&virt_coords));
+                }
+            })
+        }
+        self.surfaces = Some(surfaces);
     }
 }