add benchmark; change delta_x and rigidity to match gm

benchmark/liquid_rescale.js

@@ -0,0 +1,43 @@
+const path = require('node:path');
+const fs = require('node:fs');
+const concolor = require('concolor');
+const gm = require('gm').subClass({ imageMagick: true });
+const { liquidRescale } = require('../dist/index.js');
+const { Suite } = require('benchmark');
+
+const image = fs.readFileSync(path.join(path.resolve(), 'benchmark', 'bear.png'));
+const suite = new Suite("Liquid rescale and resize image");
+
+function liquidRescaleWithGm() {
+    return new Promise((resolve, reject) => {
+        gm(image).size((err, size) => {
+            if (err) reject(err);
+
+            const width = size.width;
+            const height = size.height;
+
+            gm(image).out('-liquid-rescale', "400x400")
+                .toBuffer('JPEG', (err, buf) => {
+                    if (err) reject(err);
+
+                    gm(buf).resize(width, height)
+                        .toBuffer('JPEG', (err, buf) => {
+                            err ? reject(err) : resolve(buf);
+                        });
+                });
+        });
+    });
+}
+
+suite
+    .add('gm', async () => {
+        await liquidRescaleWithGm();
+    })
+    .add('native', async () => {
+        await liquidRescale(image, 400, 400);
+    })
+    .on('cycle', (event) => console.info(String(event.target)))
+    .on('complete', function () {
+        console.info(`${this.name} bench suite: Fastest is ${concolor`${this.filter('fastest').map('name')}(green)`}`);
+    })
+    .run({ async: true });