From c1f0959992264be4cc62f55012a5133ad0e29a4b Mon Sep 17 00:00:00 2001
From: Michael Kefeder <m.kefeder@gmail.com>
Date: Sun, 17 May 2020 21:05:31 +0200
Subject: [PATCH 1/2] use js_sys::Uint8Array instead of as_ptr()

---
 Cargo.toml   |  1 +
 src/lib.rs   | 20 ++++++++------------
 www/index.js |  3 +--
 3 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index e55f7af..614f311 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,6 +12,7 @@ default = ["console_error_panic_hook"]
 [dependencies]
 cfg-if = "0.1.2"
 wasm-bindgen = "0.2"
+js-sys = "0.3"
 
 # The `console_error_panic_hook` crate provides better debugging of panics by
 # logging them with `console.error`. This is great for development, but requires
diff --git a/src/lib.rs b/src/lib.rs
index 4ee0f69..b921778 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,6 +5,7 @@ extern crate web_sys;
 mod utils;
 
 use std::fmt;
+use std::mem;
 use wasm_bindgen::prelude::*;
 use web_sys::console;
 
@@ -71,17 +72,9 @@ impl Universe {
     fn live_neighbor_count(&self, row: u32, column: u32) -> u8 {
         let mut count = 0;
 
-        let north = if row == 0 {
-            self.height - 1
-        } else {
-            row - 1
-        };
+        let north = if row == 0 { self.height - 1 } else { row - 1 };
 
-        let south = if row == self.height - 1 {
-            0
-        } else {
-            row + 1
-        };
+        let south = if row == self.height - 1 { 0 } else { row + 1 };
 
         let west = if column == 0 {
             self.width - 1
@@ -208,8 +201,11 @@ impl Universe {
         self.cells = (0..self.width * height).map(|_i| Cell::Dead).collect();
     }
 
-    pub fn cells(&self) -> *const Cell {
-        self.cells.as_ptr()
+    pub fn cells(&self) -> js_sys::Uint8Array {
+        unsafe {
+            let u8_cells = mem::transmute::<&Vec<Cell>, &Vec<u8>>(&self.cells);
+            js_sys::Uint8Array::view(&u8_cells)
+        }
     }
 
     pub fn toggle_cell(&mut self, row: u32, column: u32) {
diff --git a/www/index.js b/www/index.js
index 6f1c15f..11c6167 100644
--- a/www/index.js
+++ b/www/index.js
@@ -126,8 +126,7 @@ const getIndex = (row, column) => {
 };
 
 const drawCells = () => {
-  const cellsPtr = universe.cells();
-  const cells = new Uint8Array(memory.buffer, cellsPtr, width * height);
+  const cells = universe.cells();
 
   ctx.beginPath();
 

From ce4efde3782b94b145b839fd9f55b69dc857929f Mon Sep 17 00:00:00 2001
From: Michael Kefeder <m.kefeder@gmail.com>
Date: Sun, 17 May 2020 21:16:51 +0200
Subject: [PATCH 2/2] import of linear memory is not needed

---
 www/index.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/www/index.js b/www/index.js
index 11c6167..1015361 100644
--- a/www/index.js
+++ b/www/index.js
@@ -1,5 +1,4 @@
 import { Universe, Cell } from "wasm-game-of-life";
-import { memory } from "wasm-game-of-life/wasm_game_of_life_bg";
 
 const CELL_SIZE = 5; // px
 const GRID_COLOR = "#CCCCCC";