Merge pull request #1903 from ali1234/flipmode

Implement per-image flipping

src/navigator.js

@@ -452,6 +452,7 @@ $.extend( $.Navigator.prototype, $.EventSource.prototype, $.Viewer.prototype, /*
         myItem.setWidth(bounds.width, immediately);
         myItem.setRotation(theirItem.getRotation(), immediately);
         myItem.setClip(theirItem.getClip());
+        myItem.setFlip(theirItem.getFlip());
     },
 
     // private

src/tile.js

@@ -176,6 +176,12 @@ $.Tile = function(level, x, y, bounds, exists, url, context2D, loadWithAjax, aja
      * @memberof OpenSeadragon.Tile#
      */
     this.size       = null;
+    /**
+     * Whether to flip the tile when rendering.
+     * @member {Boolean} flipped
+     * @memberof OpenSeadragon.Tile#
+     */
+    this.flipped    = false;
     /**
      * The start time of this tile's blending.
      * @member {Number} blendStart
@@ -296,6 +302,10 @@ $.Tile.prototype = {
         this.style.height  = this.size.y + "px";
         this.style.width   = this.size.x + "px";
 
+        if (this.flipped) {
+            this.style.transform = "scaleX(-1)";
+        }
+
         $.setElementOpacity( this.element, this.opacity );
     },
 
@@ -376,13 +386,17 @@ $.Tile.prototype = {
             sourceHeight = rendered.canvas.height;
         }
 
+        context.translate(position.x + size.x / 2, 0);
+        if (this.flipped) {
+            context.scale(-1, 1);
+        }
         context.drawImage(
             rendered.canvas,
             0,
             0,
             sourceWidth,
             sourceHeight,
-            position.x,
+            -size.x / 2,
             position.y,
             size.x,
             size.y

src/tiledimage.js

@@ -392,6 +392,26 @@ $.extend($.TiledImage.prototype, $.EventSource.prototype, /** @lends OpenSeadrag
         return bounds.rotate(this.getRotation(current), this._getRotationPoint(current));
     },
 
+    /**
+     * @function
+     * @param {Number} level
+     * @param {Number} x
+     * @param {Number} y
+     * @returns {OpenSeadragon.Rect} Where this tile fits (in normalized coordinates).
+     */
+    getTileBounds: function( level, x, y ) {
+        var numTiles = this.source.getNumTiles(level);
+        var xMod    = ( numTiles.x + ( x % numTiles.x ) ) % numTiles.x;
+        var yMod    = ( numTiles.y + ( y % numTiles.y ) ) % numTiles.y;
+        var bounds = this.source.getTileBounds(level, xMod, yMod);
+        if (this.getFlip()) {
+            bounds.x = 1 - bounds.x - bounds.width;
+        }
+        bounds.x += (x - xMod) / numTiles.x;
+        bounds.y += (this._worldHeightCurrent / this._worldWidthCurrent) * ((y - yMod) / numTiles.y);
+        return bounds;
+    },
+
     /**
      * @returns {OpenSeadragon.Point} This TiledImage's content size, in original pixels.
      */
@@ -832,6 +852,23 @@ $.extend($.TiledImage.prototype, $.EventSource.prototype, /** @lends OpenSeadrag
         this.raiseEvent('clip-change');
     },
 
+    /**
+     * @returns {Boolean} Whether the TiledImage should be flipped before rendering.
+     */
+    getFlip: function() {
+        return !!this.flipped;
+    },
+
+    /**
+     * @param {Boolean} flip Whether the TiledImage should be flipped before rendering.
+     * @fires OpenSeadragon.TiledImage.event:bounds-change
+     */
+    setFlip: function(flip) {
+        this.flipped = !!flip;
+        this._needsDraw = true;
+        this._raiseBoundsChange();
+    },
+
     /**
      * @returns {Number} The TiledImage's current opacity.
      */
@@ -1255,24 +1292,41 @@ function updateLevel(tiledImage, haveDrawn, drawLevel, level, levelOpacity,
 
     var viewportCenter = tiledImage.viewport.pixelFromPoint(
         tiledImage.viewport.getCenter());
+
+    if (tiledImage.getFlip()) {
+        // The right-most tile can be narrower than the others. When flipped,
+        // this tile is now on the left. Because it is narrower than the normal
+        // left-most tile, the subsequent tiles may not be wide enough to completely
+        // fill the viewport. Fix this by rendering an extra column of tiles. If we
+        // are not wrapping, make sure we never render more than the number of tiles
+        // in the image.
+        bottomRightTile.x += 1;
+        if (!tiledImage.wrapHorizontal) {
+            bottomRightTile.x  = Math.min(bottomRightTile.x, numberOfTiles.x - 1);
+        }
+    }
+
     for (var x = topLeftTile.x; x <= bottomRightTile.x; x++) {
         for (var y = topLeftTile.y; y <= bottomRightTile.y; y++) {
 
-            // Optimisation disabled with wrapping because getTileBounds does not
-            // work correctly with x and y outside of the number of tiles
-            if (!tiledImage.wrapHorizontal && !tiledImage.wrapVertical) {
-                var tileBounds = tiledImage.source.getTileBounds(level, x, y);
-                if (drawArea.intersection(tileBounds) === null) {
-                    // This tile is outside of the viewport, no need to draw it
-                    continue;
-                }
+            var flippedX;
+            if (tiledImage.getFlip()) {
+                var xMod = ( numberOfTiles.x + ( x % numberOfTiles.x ) ) % numberOfTiles.x;
+                flippedX = x + numberOfTiles.x - xMod - xMod - 1;
+            } else {
+                flippedX = x;
+            }
+
+            if (drawArea.intersection(tiledImage.getTileBounds(level, flippedX, y)) === null) {
+                // This tile is outside of the viewport, no need to draw it
+                continue;
             }
 
             best = updateTile(
                 tiledImage,
                 drawLevel,
                 haveDrawn,
-                x, y,
+                flippedX, y,
                 level,
                 levelOpacity,
                 levelVisibility,
@@ -1447,10 +1501,10 @@ function getTile(
         tilesMatrix[ level ][ x ] = {};
     }
 
-    if ( !tilesMatrix[ level ][ x ][ y ] ) {
+    if ( !tilesMatrix[ level ][ x ][ y ] || !tilesMatrix[ level ][ x ][ y ].flipped !== !tiledImage.flipped ) {
         xMod    = ( numTiles.x + ( x % numTiles.x ) ) % numTiles.x;
         yMod    = ( numTiles.y + ( y % numTiles.y ) ) % numTiles.y;
-        bounds  = tileSource.getTileBounds( level, xMod, yMod );
+        bounds  = tiledImage.getTileBounds( level, x, y );
         sourceBounds = tileSource.getTileBounds( level, xMod, yMod, true );
         exists  = tileSource.tileExists( level, xMod, yMod );
         url     = tileSource.getTileUrl( level, xMod, yMod );
@@ -1469,9 +1523,6 @@ function getTile(
         context2D = tileSource.getContext2D ?
             tileSource.getContext2D(level, xMod, yMod) : undefined;
 
-        bounds.x += ( x - xMod ) / numTiles.x;
-        bounds.y += (worldHeight / worldWidth) * (( y - yMod ) / numTiles.y);
-
         tile = new $.Tile(
             level,
             x,
@@ -1485,14 +1536,22 @@ function getTile(
             sourceBounds
         );
 
-        if (xMod === numTiles.x - 1) {
-            tile.isRightMost = true;
+        if (tiledImage.getFlip()) {
+            if (xMod === 0) {
+                tile.isRightMost = true;
+            }
+        } else {
+            if (xMod === numTiles.x - 1) {
+                tile.isRightMost = true;
+            }
         }
 
         if (yMod === numTiles.y - 1) {
             tile.isBottomMost = true;
         }
 
+        tile.flipped = tiledImage.flipped;
+
         tilesMatrix[ level ][ x ][ y ] = tile;
     }
 

src/viewer.js

@@ -1301,6 +1301,7 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
      * @param {Boolean} [options.preload=false]  Default switch for loading hidden images (true loads, false blocks)
      * @param {Number} [options.degrees=0] Initial rotation of the tiled image around
      * its top left corner in degrees.
+     * @param {Boolean} [options.flipped=false] Whether to horizontally flip the image.
      * @param {String} [options.compositeOperation] How the image is composited onto other images.
      * @param {String} [options.crossOriginPolicy] The crossOriginPolicy for this specific image,
      * overriding viewer.crossOriginPolicy.
@@ -1463,6 +1464,7 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
                     opacity: queueItem.options.opacity,
                     preload: queueItem.options.preload,
                     degrees: queueItem.options.degrees,
+                    flipped: queueItem.options.flipped,
                     compositeOperation: queueItem.options.compositeOperation,
                     springStiffness: _this.springStiffness,
                     animationTime: _this.animationTime,

test/demo/flipping.html

@@ -0,0 +1,113 @@
+<!DOCTYPE html>
+<html>
+    <head>
+        <title>OpenSeadragon Flipping Demo</title>
+        <script type="text/javascript" src='../../build/openseadragon/openseadragon.js'></script>
+        <script type="text/javascript" src='../lib/jquery-1.9.1.min.js'></script>
+        <style type="text/css">
+
+            .openseadragon1 {
+                width: 800px;
+                height: 600px;
+                float: left;
+            }
+
+            .options {
+                margin: 0.5em;
+            }
+
+            .button {
+                margin: 0.3em;
+            }
+
+        </style>
+    </head>
+    <body>
+    <div>
+        Simple demo page to show image flipping.
+    </div>
+    <div id="contentDiv" class="openseadragon1">
+
+
+    </div>
+    <div class="options">
+        First
+        <div class="button">
+            <input type="checkbox" id="ffirst" onchange="flip(0, this.checked)">
+            <label for="ffirst">Flip</label>
+        </div>
+        <div class="button">
+            <input type="checkbox" id="rfirst" onchange="rotate(0, this.checked * 45)">
+            <label for="rfirst">Rotate</label>
+        </div>
+    </div>
+
+    <div class="options">
+        Second
+        <div class="button">
+            <input type="checkbox" id="fsecond" onchange="flip(1, this.checked)" checked>
+            <label for="fsecond">Flip</label>
+        </div>
+        <div class="button">
+            <input type="checkbox" id="rsecond" onchange="rotate(1, this.checked * 45)">
+            <label for="rsecond">Rotate</label>
+        </div>
+    </div>
+
+    <div class="options">
+        Viewport
+        <div class="button">
+            <input type="checkbox" id="fview" onchange="flipViewport(this.checked)">
+            <label for="fview">Flip Viewport</label>
+        </div>
+
+        <div class="button">
+            <input type="checkbox" id="debug" onchange="debug(this.checked)">
+            <label for="debug">Debug Mode</label>
+        </div>
+    </div>
+    <script type="text/javascript">
+
+        var viewer = OpenSeadragon({
+            // debugMode: true,
+            id: "contentDiv",
+            prefixUrl: "../../build/openseadragon/images/",
+            showNavigator:true,
+            tileSources: [
+                {
+                    tileSource: "../data/testpattern.dzi",
+                    x: 0,
+                    y: 0,
+                    flipped: document.getElementById("ffirst").checked,
+                    degrees: document.getElementById("rfirst").checked * 45,
+                }, {
+                    tileSource: "../data/testpattern.dzi",
+                    x: 1,
+                    y: 0,
+                    flipped: document.getElementById("fsecond").checked,
+                    degrees: document.getElementById("rsecond").checked * 45,
+                }
+            ]
+        });
+
+        viewer.viewport.setFlip(document.getElementById("fview").checked);
+
+        function debug(v) {
+            viewer.setDebugMode(v);
+        }
+
+        function flip(n, v) {
+            viewer.world.getItemAt(n).setFlip(v);
+        }
+
+        function rotate(n, v) {
+            viewer.world.getItemAt(n).setRotation(v);
+        }
+
+        function flipViewport(v) {
+            viewer.viewport.setFlip(v);
+        }
+
+    </script>
+    </body>
+</html>