Wrote image stitcher

tools/stitcher/index.js

@@ -0,0 +1,88 @@
+const fs = require("fs");
+const path = require('path');
+const { PNG } = require("pngjs");
+
+// Constants
+const IMAGES_ROOT = path.join(...[
+  '.', 
+  'assets',
+  'characters',
+  'penny',
+  'Sample sets',
+  'Eyes'
+]);
+
+const FILE_OUT = 
+
+
+// Code
+const imageLoad = (image) => new Promise(resolve => {
+  fs.createReadStream(image)
+    .pipe(new PNG({ filterType: 4 }))
+    .on("parsed", function () {
+      // Normalize
+      const pixels = [];
+      for(let y = 0; y < this.height; y++) {
+        for(let x = 0; x < this.width; x++) {
+          const idx = (this.width * y + x) << 2;
+          const r = this.data[idx];
+          const g = this.data[idx + 1];
+          const b = this.data[idx + 2];
+          const a = this.data[idx + 3];
+
+          pixels.push({ r, g, b, a });
+        }
+      }
+      resolve({ pixels, width: this.width, height: this.height });
+    })
+  ;
+});
+
+const imageWrite = (image, file) => new Promise(resolve => {
+  const png = new PNG({ width: image.width, height: image.height });
+  png.width = image.width;
+  png.height = image.height;
+  
+  for(let y = 0; y < image.height; y++) {
+    for(let x = 0; x < image.width; x++) {
+      const i = (image.width * y + x);
+      const idx = i << 2;
+
+      const pixel = image.pixels[i];
+      png.data[idx] = pixel.r;
+      png.data[idx + 1] = pixel.g;
+      png.data[idx + 2] = pixel.b;
+      png.data[idx + 3] = pixel.a;
+    }
+  }
+
+  png.pack().pipe(fs.createWriteStream(file))
+    .on('close', () => resolve(true))
+  ;
+});
+
+(async () => {
+  const files = fs.readdirSync(IMAGES_ROOT);
+
+  let stitched = null;
+  let k = 0;
+  
+  for(let i = 0; i < files.length; i++) {
+    const filePath = path.join(IMAGES_ROOT, files[i]);
+    const image = await imageLoad(filePath);
+
+    if(!stitched) {
+      stitched = {  
+        width: image.width,
+        height: image.height * files.length,
+        pixels: Array(image.width*image.height*files.length)
+      }
+    }
+
+    for(let j = 0; j < image.pixels.length; j++) {
+      stitched.pixels[j + (i * image.width * image.height)] = { ...image.pixels[j] };
+    }
+  };
+
+  await imageWrite(stitched, FILE_OUT);
+})().catch(console.error);