Crop image at image_loader.

ui/file_manager/image_loader/image_loader_unittest.js

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * Test case:
+ * - Source image: 200x50
+ * - Target: max size is 100x100
+ */
+function testNormalImage() {
+  var source = new Image();
+  source.width = 200;
+  source.height = 50;
+  var options = {
+    maxWidth: 100,
+    maxHeight: 100
+  };
+  var result = ImageLoader.calculateCopyParameters(source, options);
+  assertEquals(0, result.source.x);
+  assertEquals(0, result.source.y);
+  assertEquals(200, result.source.width);
+  assertEquals(50, result.source.height);
+  assertEquals(0, result.target.x);
+  assertEquals(0, result.target.y);
+  assertEquals(100, result.target.width);
+  assertEquals(25, result.target.height);
+  assertEquals(100, result.canvas.width);
+  assertEquals(25, result.canvas.height);
+};
+
+/**
+ * Test case:
+ * - Source image: 50x200 90 deg clock-wise rotated image.
+ * - Target: max size is 100x100
+ */
+function testRotatedImage() {
+  var source = new Image();
+  source.width = 50;
+  source.height = 200;
+  var options = {
+    maxWidth: 100,
+    maxHeight: 100,
+    orientation: 1
+  };
+  var result = ImageLoader.calculateCopyParameters(source, options);
+  assertEquals(0, result.source.x);
+  assertEquals(0, result.source.y);
+  assertEquals(50, result.source.width);
+  assertEquals(200, result.source.height);
+  assertEquals(0, result.target.x);
+  assertEquals(0, result.target.y);
+  assertEquals(25, result.target.width);
+  assertEquals(100, result.target.height);
+  assertEquals(100, result.canvas.width);
+  assertEquals(25, result.canvas.height);
+}
+
+/**
+ * Test case:
+ * - Source image: 800x100
+ * - Target: 50x50 cropped image.
+ */
+function testCroppedImage() {
+  var source = new Image();
+  source.width = 800;
+  source.height = 100;
+  var options = {
+    width: 50,
+    height: 50,
+    crop: true
+  };
+  var result = ImageLoader.calculateCopyParameters(source, options);
+  assertEquals(350, result.source.x);
+  assertEquals(0, result.source.y);
+  assertEquals(100, result.source.width);
+  assertEquals(100, result.source.height);
+  assertEquals(0, result.target.x);
+  assertEquals(0, result.target.y);
+  assertEquals(50, result.target.width);
+  assertEquals(50, result.target.height);
+  assertEquals(50, result.canvas.width);
+  assertEquals(50, result.canvas.height);
+}
+
+/**
+ * Test case:
+ * - Source image: 200x25
+ * - Target: 50x50 cropped image.
+ */
+function testCroppedImageWithResize() {
+  var source = new Image();
+  source.width = 200;
+  source.height = 25;
+  var options = {
+    width: 50,
+    height: 50,
+    crop: true
+  };
+  var result = ImageLoader.calculateCopyParameters(source, options);
+  assertEquals(87, result.source.x);
+  assertEquals(0, result.source.y);
+  assertEquals(25, result.source.width);
+  assertEquals(25, result.source.height);
+  assertEquals(0, result.target.x);
+  assertEquals(0, result.target.y);
+  assertEquals(50, result.target.width);
+  assertEquals(50, result.target.height);
+  assertEquals(50, result.canvas.width);
+  assertEquals(50, result.canvas.height);
+}
+
+/**
+ * Test case:
+ * - Source image: 20x10
+ * - Target: 50x50 cropped image.
+ */
+function testCroppedTinyImage() {
+  var source = new Image();
+  source.width = 20;
+  source.height = 10;
+  var options = {
+    width: 50,
+    height: 50,
+    crop: true
+  };
+  var result = ImageLoader.calculateCopyParameters(source, options);
+  assertEquals(5, result.source.x);
+  assertEquals(0, result.source.y);
+  assertEquals(10, result.source.width);
+  assertEquals(10, result.source.height);
+  assertEquals(0, result.target.x);
+  assertEquals(0, result.target.y);
+  assertEquals(50, result.target.width);
+  assertEquals(50, result.target.height);
+  assertEquals(50, result.canvas.width);
+  assertEquals(50, result.canvas.height);
+}
+
+/**
+ * Test case:
+ * - Source image: 100x400 90 degree clock-wise rotated.
+ * - Target: 50x50 cropped image
+ */
+function testCroppedRotatedImage() {
+  var source = new Image();
+  source.width = 100;
+  source.height = 400;
+  var options = {
+    width: 50,
+    height: 50,
+    crop: true,
+    orientation: 1
+  };
+  var result = ImageLoader.calculateCopyParameters(source, options);
+  assertEquals(0, result.source.x);
+  assertEquals(150, result.source.y);
+  assertEquals(100, result.source.width);
+  assertEquals(100, result.source.height);
+  assertEquals(0, result.target.x);
+  assertEquals(0, result.target.y);
+  assertEquals(50, result.target.width);
+  assertEquals(50, result.target.height);
+  assertEquals(50, result.canvas.width);
+  assertEquals(50, result.canvas.height);
+}