2D CA from uploaded picture

src/modules/picture.js

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+// https://stackoverflow.com/questions/4492385/convert-simple-array-into-two-dimensional-array-matrix
+// convert a 1D array into a 2D matrix
+export function toMatrix(array, width) {
+  return array.reduce(
+    (rows, key, index) =>
+      (index % width == 0
+        ? rows.push([key])
+        : rows[rows.length - 1].push(key)) && rows,
+    []
+  );
+}
+
+// convert an image into a black and white image
+export function picToBlackAndWhite(pixels, width, height) {
+  return pixels.reduce((acc, pixel, index) => {
+    if (index % 4 == 0) {
+      const count = pixels[index] + pixels[index + 1] + pixels[index + 2];
+      const colour = count >= 255 ? 255 : 1;
+      acc.data[index] = colour;
+      acc.data[index + 1] = colour;
+      acc.data[index + 2] = colour;
+      acc.data[index + 3] = 255;
+    }
+    return acc;
+  }, new ImageData(width, height));
+}
+
+// convert an ImageData into a 2D array of boolean (0, 1) values
+export function picToBoard(pixels, width, height) {
+  const flat = pixels.reduce((acc, pixel, index) => {
+    if (index % 4 == 0) {
+      const count = pixels[index] + pixels[index + 1] + pixels[index + 2];
+      const value = count >= 255 ? 1 : 0;
+      acc.push(value);
+    }
+    return acc;
+  }, []);
+  return toMatrix(flat, Math.max(width, height));
+}