Normalize the rectangles

src/rectangle.js

@@ -43,6 +43,8 @@
  * y increases when going to the bottom
  * degrees increases clockwise with 0 being the horizontal
  *
+ * The constructor normalizes the rectangle to always have 0 <= degrees < 90
+ *
  * @memberof OpenSeadragon
  * @param {Number} [x=0] The vector component 'x'.
  * @param {Number} [y=0] The vector component 'y'.
@@ -77,6 +79,35 @@ $.Rect = function(x, y, width, height, degrees) {
     this.height = typeof(height) === "number" ? height : 0;
 
     this.degrees = typeof(degrees) === "number" ? degrees : 0;
+
+    // Normalizes the rectangle.
+    this.degrees = this.degrees % 360;
+    if (this.degrees < 0) {
+        this.degrees += 360;
+    }
+    var newTopLeft, newWidth;
+    if (this.degrees >= 270) {
+        newTopLeft = this.getTopRight();
+        this.x = newTopLeft.x;
+        this.y = newTopLeft.y;
+        newWidth = this.height;
+        this.height = this.width;
+        this.width = newWidth;
+        this.degrees -= 270;
+    } else if (this.degrees >= 180) {
+        newTopLeft = this.getBottomRight();
+        this.x = newTopLeft.x;
+        this.y = newTopLeft.y;
+        this.degrees -= 180;
+    } else if (this.degrees >= 90) {
+        newTopLeft = this.getBottomLeft();
+        this.x = newTopLeft.x;
+        this.y = newTopLeft.y;
+        newWidth = this.height;
+        this.height = this.width;
+        this.width = newWidth;
+        this.degrees -= 90;
+    }
 };
 
 $.Rect.prototype = /** @lends OpenSeadragon.Rect.prototype */{
@@ -257,10 +288,13 @@ $.Rect.prototype = /** @lends OpenSeadragon.Rect.prototype */{
      * @return {OpenSeadragon.Rect}
      */
     rotate: function(degrees, pivot) {
-        degrees = (degrees + 360) % 360;
+        degrees = degrees % 360;
         if (degrees === 0) {
             return this.clone();
         }
+        if (degrees < 0) {
+            degrees += 360;
+        }
 
         pivot = pivot || this.getCenter();
         var newTopLeft = this.getTopLeft().rotate(degrees, pivot);

test/modules/rectangle.js

@@ -15,11 +15,11 @@
         Util.assessNumericValue(rectA.x, rectB.x, precision, message + " x: ");
         Util.assessNumericValue(rectA.y, rectB.y, precision, message + " y: ");
         Util.assessNumericValue(rectA.width, rectB.width, precision,
-                message + " width: ");
+            message + " width: ");
         Util.assessNumericValue(rectA.height, rectB.height, precision,
-                message + " height: ");
+            message + " height: ");
         Util.assessNumericValue(rectA.degrees, rectB.degrees, precision,
-                message + " degrees: ");
+            message + " degrees: ");
     }
 
     test('Constructor', function() {
@@ -36,6 +36,39 @@
         strictEqual(rect.width, 0, 'rect.width should be 0');
         strictEqual(rect.height, 0, 'rect.height should be 0');
         strictEqual(rect.degrees, 0, 'rect.degrees should be 0');
+
+        rect = new OpenSeadragon.Rect(0, 0, 1, 2, -405);
+        Util.assessNumericValue(Math.sqrt(2) / 2, rect.x, precision,
+            'rect.x should be sqrt(2)/2');
+        Util.assessNumericValue(-Math.sqrt(2) / 2, rect.y, precision,
+            'rect.y should be -sqrt(2)/2');
+        Util.assessNumericValue(2, rect.width, precision,
+            'rect.width should be 2');
+        Util.assessNumericValue(1, rect.height, precision,
+            'rect.height should be 1');
+        strictEqual(45, rect.degrees, 'rect.degrees should be 45');
+
+        rect = new OpenSeadragon.Rect(0, 0, 1, 2, 135);
+        Util.assessNumericValue(-Math.sqrt(2), rect.x, precision,
+            'rect.x should be -sqrt(2)');
+        Util.assessNumericValue(-Math.sqrt(2), rect.y, precision,
+            'rect.y should be -sqrt(2)');
+        Util.assessNumericValue(2, rect.width, precision,
+            'rect.width should be 2');
+        Util.assessNumericValue(1, rect.height, precision,
+            'rect.height should be 1');
+        strictEqual(45, rect.degrees, 'rect.degrees should be 45');
+
+        rect = new OpenSeadragon.Rect(0, 0, 1, 1, 585);
+        Util.assessNumericValue(0, rect.x, precision,
+            'rect.x should be 0');
+        Util.assessNumericValue(-Math.sqrt(2), rect.y, precision,
+            'rect.y should be -sqrt(2)');
+        Util.assessNumericValue(1, rect.width, precision,
+            'rect.width should be 1');
+        Util.assessNumericValue(1, rect.height, precision,
+            'rect.height should be 1');
+        strictEqual(45, rect.degrees, 'rect.degrees should be 45');
     });
 
     test('getTopLeft', function() {
@@ -52,7 +85,7 @@
         rect.degrees = 45;
         expected = new OpenSeadragon.Point(1 / Math.sqrt(2), 1 / Math.sqrt(2));
         assertPointsEquals(expected, rect.getTopRight(),
-                "Incorrect top right point with rotation.");
+            "Incorrect top right point with rotation.");
     });
 
     test('getBottomLeft', function() {
@@ -63,7 +96,7 @@
         rect.degrees = 45;
         expected = new OpenSeadragon.Point(-1 / Math.sqrt(2), 1 / Math.sqrt(2));
         assertPointsEquals(expected, rect.getBottomLeft(),
-                "Incorrect bottom left point with rotation.");
+            "Incorrect bottom left point with rotation.");
     });
 
     test('getBottomRight', function() {
@@ -74,17 +107,17 @@
         rect.degrees = 45;
         expected = new OpenSeadragon.Point(0, Math.sqrt(2));
         assertPointsEquals(expected, rect.getBottomRight(),
-                "Incorrect bottom right point with 45 rotation.");
+            "Incorrect bottom right point with 45 rotation.");
 
         rect.degrees = 90;
         expected = new OpenSeadragon.Point(-1, 1);
         assertPointsEquals(expected, rect.getBottomRight(),
-                "Incorrect bottom right point with 90 rotation.");
+            "Incorrect bottom right point with 90 rotation.");
 
         rect.degrees = 135;
         expected = new OpenSeadragon.Point(-Math.sqrt(2), 0);
         assertPointsEquals(expected, rect.getBottomRight(),
-                "Incorrect bottom right point with 135 rotation.");
+            "Incorrect bottom right point with 135 rotation.");
     });
 
     test('getCenter', function() {
@@ -95,17 +128,31 @@
         rect.degrees = 45;
         expected = new OpenSeadragon.Point(0, 0.5 * Math.sqrt(2));
         assertPointsEquals(expected, rect.getCenter(),
-                "Incorrect bottom right point with 45 rotation.");
+            "Incorrect bottom right point with 45 rotation.");
 
         rect.degrees = 90;
         expected = new OpenSeadragon.Point(-0.5, 0.5);
         assertPointsEquals(expected, rect.getCenter(),
-                "Incorrect bottom right point with 90 rotation.");
+            "Incorrect bottom right point with 90 rotation.");
 
         rect.degrees = 135;
         expected = new OpenSeadragon.Point(-0.5 * Math.sqrt(2), 0);
         assertPointsEquals(expected, rect.getCenter(),
-                "Incorrect bottom right point with 135 rotation.");
+            "Incorrect bottom right point with 135 rotation.");
+    });
+
+    test('times', function() {
+        var rect = new OpenSeadragon.Rect(1, 2, 3, 4, 45);
+        var expected = new OpenSeadragon.Rect(2, 4, 6, 8, 45);
+        var actual = rect.times(2);
+        assertRectangleEquals(expected, actual, "Incorrect x2 rectangles.");
+    });
+
+    test('translate', function() {
+        var rect = new OpenSeadragon.Rect(1, 2, 3, 4, 45);
+        var expected = new OpenSeadragon.Rect(2, 4, 3, 4, 45);
+        var actual = rect.translate(new OpenSeadragon.Point(1, 2));
+        assertRectangleEquals(expected, actual, "Incorrect translation.");
     });
 
     test('union', function() {
@@ -114,7 +161,7 @@
         var expected = new OpenSeadragon.Rect(0, 1, 4, 4);
         var actual = rect1.union(rect2);
         assertRectangleEquals(expected, actual,
-                "Incorrect union with horizontal rectangles.");
+            "Incorrect union with horizontal rectangles.");
 
         rect1 = new OpenSeadragon.Rect(0, -Math.sqrt(2), 2, 2, 45);
         rect2 = new OpenSeadragon.Rect(1, 0, 2, 2, 0);
@@ -125,7 +172,7 @@
             2 + Math.sqrt(2));
         actual = rect1.union(rect2);
         assertRectangleEquals(expected, actual,
-                "Incorrect union with non horizontal rectangles.");
+            "Incorrect union with non horizontal rectangles.");
     });
 
     test('rotate', function() {
@@ -137,29 +184,29 @@
             2,
             1,
             45);
-        var actual = rect.rotate(45);
+        var actual = rect.rotate(-675);
         assertRectangleEquals(expected, actual,
-                "Incorrect rectangle after rotation of 45deg around center.");
+            "Incorrect rectangle after rotation of -675deg around center.");
 
         expected = new OpenSeadragon.Rect(0, 0, 2, 1, 33);
         actual = rect.rotate(33, rect.getTopLeft());
         assertRectangleEquals(expected, actual,
-                "Incorrect rectangle after rotation of 33deg around topLeft.");
+            "Incorrect rectangle after rotation of 33deg around topLeft.");
 
         expected = new OpenSeadragon.Rect(0, 0, 2, 1, 101);
         actual = rect.rotate(101, rect.getTopLeft());
         assertRectangleEquals(expected, actual,
-                "Incorrect rectangle after rotation of 187deg around topLeft.");
+            "Incorrect rectangle after rotation of 187deg around topLeft.");
 
         expected = new OpenSeadragon.Rect(0, 0, 2, 1, 187);
         actual = rect.rotate(187, rect.getTopLeft());
         assertRectangleEquals(expected, actual,
-                "Incorrect rectangle after rotation of 187deg around topLeft.");
+            "Incorrect rectangle after rotation of 187deg around topLeft.");
 
         expected = new OpenSeadragon.Rect(0, 0, 2, 1, 300);
         actual = rect.rotate(300, rect.getTopLeft());
         assertRectangleEquals(expected, actual,
-                "Incorrect rectangle after rotation of 300deg around topLeft.");
+            "Incorrect rectangle after rotation of 300deg around topLeft.");
     });
 
     test('getBoundingBox', function() {
@@ -167,22 +214,22 @@
 
         var bb = rect.getBoundingBox();
         ok(rect.equals(bb), "Bounding box of horizontal rectangle should be " +
-                "identical to rectangle.");
+            "identical to rectangle.");
 
         rect.degrees = 90;
         var expected = new OpenSeadragon.Rect(-3, 0, 3, 2);
         assertRectangleEquals(expected, rect.getBoundingBox(),
-                "Bounding box of rect rotated 90deg.");
+            "Bounding box of rect rotated 90deg.");
 
         rect.degrees = 180;
         var expected = new OpenSeadragon.Rect(-2, -3, 2, 3);
         assertRectangleEquals(expected, rect.getBoundingBox(),
-                "Bounding box of rect rotated 180deg.");
+            "Bounding box of rect rotated 180deg.");
 
         rect.degrees = 270;
         var expected = new OpenSeadragon.Rect(0, -2, 3, 2);
         assertRectangleEquals(expected, rect.getBoundingBox(),
-                "Bounding box of rect rotated 270deg.");
+            "Bounding box of rect rotated 270deg.");
     });
 
 })();