dirty initial commit

game/Bitmap.js

@@ -0,0 +1,78 @@
+import BoundingRectangle from './BoundingRectangle.js'
+
+export default class Bitmap {
+    constructor(width, height, rgba = null) {
+        this._w = width
+        this._h = height
+        this._com = 4 // number of components per pixel (RGBA)
+        this._boundingRect = new BoundingRectangle(0, this._w - 1, 0, this._h -1)
+        const len = this._w * this._h * this._com
+        this._data = new Uint8ClampedArray(len)
+        if (rgba) {
+            for (let i = 0; i < len; i+=4) {
+                this._data[i] = rgba[0]
+                this._data[i + 1] = rgba[1]
+                this._data[i + 2] = rgba[2]
+                this._data[i + 3] = rgba[3]
+            }
+        }
+
+        // public
+        this.width = this._w
+        this.height = this._h
+    }
+
+    toImage() {
+        const canvas = document.createElement('canvas');
+        const ctx = canvas.getContext('2d');
+
+        canvas.width = this._w;
+        canvas.height = this._h;
+
+        const imgData = ctx.createImageData(canvas.width, canvas.height);
+        imgData.data.set(this._data);
+        ctx.putImageData(imgData, 0, 0);
+
+
+        return new Promise((resolve) => {
+
+            const img = document.createElement('img')
+            img.onload = () => {
+                resolve(img)
+            }
+            img.src = canvas.toDataURL()
+            return img
+        })
+    }
+    
+    getPix(x, y, out) {
+        if (x < 0 ||  y < 0 || x >= this._w || y >= this._h) {
+            return false;
+        }
+        x = Math.round(x)
+        y = Math.round(y)
+        const idx = (y * 4 * this._w) + (x * 4)
+        out[0] = this._data[idx]
+        out[1] = this._data[idx + 1]
+        out[2] = this._data[idx + 2]
+        out[3] = this._data[idx + 3]
+        return true
+    }
+
+    putPix(x, y, rgba) {
+        if (x < 0 ||  y < 0 || x >= this._w || y >= this._h) {
+            return;
+        }
+        x = Math.round(x)
+        y = Math.round(y)
+        const idx = (y * this._com * this._w) + (x * this._com)
+        this._data[idx] = rgba[0]
+        this._data[idx + 1] = rgba[1]
+        this._data[idx + 2] = rgba[2]
+        this._data[idx + 3] = rgba[3]
+    }
+
+    getBoundingRect() {
+        return this._boundingRect
+    }
+}