更新

TongjiUniApp/node_modules/@jimp/plugin-shadow/src/index.js

@@ -0,0 +1,64 @@
+import { isNodePattern } from '@jimp/utils';
+
+/**
+ * Creates a circle out of an image.
+ * @param {function(Error, Jimp)} options (optional)
+ * opacity - opacity of the shadow between 0 and 1
+ * size,- of the shadow
+ * blur - how blurry the shadow is
+ * x- x position of shadow
+ * y - y position of shadow
+ * @param {function(Error, Jimp)} cb (optional) a callback for when complete
+ * @returns {Jimp} this for chaining of methods
+ */
+export default () => ({
+  shadow(options = {}, cb) {
+    if (typeof options === 'function') {
+      cb = options;
+      options = {};
+    }
+
+    const { opacity = 0.7, size = 1.1, x = -25, y = 25, blur = 5 } = options;
+
+    // clone the image
+    const orig = this.clone();
+    const shadow = this.clone();
+
+    // turn all it's pixels black
+    shadow.scan(
+      0,
+      0,
+      shadow.bitmap.width,
+      shadow.bitmap.height,
+      (x, y, idx) => {
+        shadow.bitmap.data[idx] = 0x00;
+        shadow.bitmap.data[idx + 1] = 0x00;
+        shadow.bitmap.data[idx + 2] = 0x00;
+        // up the opacity a little,
+        shadow.bitmap.data[idx + 3] = shadow.constructor.limit255(
+          shadow.bitmap.data[idx + 3] * opacity
+        );
+
+        this.bitmap.data[idx] = 0x00;
+        this.bitmap.data[idx + 1] = 0x00;
+        this.bitmap.data[idx + 2] = 0x00;
+        this.bitmap.data[idx + 3] = 0x00;
+      }
+    );
+
+    // enlarge it. This creates a "shadow".
+    shadow
+      .resize(shadow.bitmap.width * size, shadow.bitmap.height * size)
+      .blur(blur);
+
+    // Then blit the "shadow" onto the background and the image on top of that.
+    this.composite(shadow, x, y);
+    this.composite(orig, 0, 0);
+
+    if (isNodePattern(cb)) {
+      cb.call(this, null, this);
+    }
+
+    return this;
+  }
+});