Incremental progress toward archive loading in o3d-webgl. Implemented...

samples/o3d-webgl/archive_request.js

+/*
+ * Copyright 2010, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+// TODO(kbr): figure out how we can reuse the o3djs.io package from
+// within here.
+// o3djs.require('o3djs.io');
+
+// TODO(kbr): factor this out into e.g. o3djs.json and require
+// o3djs.json here.
+if(!this.JSON){this.JSON={};}
+(function(){function f(n){return n<10?'0'+n:n;}
+if(typeof Date.prototype.toJSON!=='function'){Date.prototype.toJSON=function(key){return isFinite(this.valueOf())?this.getUTCFullYear()+'-'+
+f(this.getUTCMonth()+1)+'-'+
+f(this.getUTCDate())+'T'+
+f(this.getUTCHours())+':'+
+f(this.getUTCMinutes())+':'+
+f(this.getUTCSeconds())+'Z':null;};String.prototype.toJSON=Number.prototype.toJSON=Boolean.prototype.toJSON=function(key){return this.valueOf();};}
+var cx=/[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,escapable=/[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,gap,indent,meta={'\b':'\\b','\t':'\\t','\n':'\\n','\f':'\\f','\r':'\\r','"':'\\"','\\':'\\\\'},rep;function quote(string){escapable.lastIndex=0;return escapable.test(string)?'"'+string.replace(escapable,function(a){var c=meta[a];return typeof c==='string'?c:'\\u'+('0000'+a.charCodeAt(0).toString(16)).slice(-4);})+'"':'"'+string+'"';}
+function str(key,holder){var i,k,v,length,mind=gap,partial,value=holder[key];if(value&&typeof value==='object'&&typeof value.toJSON==='function'){value=value.toJSON(key);}
+if(typeof rep==='function'){value=rep.call(holder,key,value);}
+switch(typeof value){case'string':return quote(value);case'number':return isFinite(value)?String(value):'null';case'boolean':case'null':return String(value);case'object':if(!value){return'null';}
+gap+=indent;partial=[];if(Object.prototype.toString.apply(value)==='[object Array]'){length=value.length;for(i=0;i<length;i+=1){partial[i]=str(i,value)||'null';}
+v=partial.length===0?'[]':gap?'[\n'+gap+
+partial.join(',\n'+gap)+'\n'+
+mind+']':'['+partial.join(',')+']';gap=mind;return v;}
+if(rep&&typeof rep==='object'){length=rep.length;for(i=0;i<length;i+=1){k=rep[i];if(typeof k==='string'){v=str(k,value);if(v){partial.push(quote(k)+(gap?': ':':')+v);}}}}else{for(k in value){if(Object.hasOwnProperty.call(value,k)){v=str(k,value);if(v){partial.push(quote(k)+(gap?': ':':')+v);}}}}
+v=partial.length===0?'{}':gap?'{\n'+gap+partial.join(',\n'+gap)+'\n'+
+mind+'}':'{'+partial.join(',')+'}';gap=mind;return v;}}
+if(typeof JSON.stringify!=='function'){JSON.stringify=function(value,replacer,space){var i;gap='';indent='';if(typeof space==='number'){for(i=0;i<space;i+=1){indent+=' ';}}else if(typeof space==='string'){indent=space;}
+rep=replacer;if(replacer&&typeof replacer!=='function'&&(typeof replacer!=='object'||typeof replacer.length!=='number')){throw new Error('JSON.stringify');}
+return str('',{'':value});};}
+if(typeof JSON.parse!=='function'){JSON.parse=function(text,reviver){var j;function walk(holder,key){var k,v,value=holder[key];if(value&&typeof value==='object'){for(k in value){if(Object.hasOwnProperty.call(value,k)){v=walk(value,k);if(v!==undefined){value[k]=v;}else{delete value[k];}}}}
+return reviver.call(holder,key,value);}
+text=String(text);cx.lastIndex=0;if(cx.test(text)){text=text.replace(cx,function(a){return'\\u'+
+('0000'+a.charCodeAt(0).toString(16)).slice(-4);});}
+if(/^[\],:{}\s]*$/.test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g,'@').replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g,']').replace(/(?:^|:|,)(?:\s*\[)+/g,''))){j=eval('('+text+')');return typeof reviver==='function'?walk({'':j},''):j;}
+throw new SyntaxError('JSON.parse');};}}());
+
+
+/**
+  An ArchiveRequest object is used to carry out an asynchronous request for a
+  compressed archive (containing multiple files).
+
+  Note: The archive must have as its first file a file named 'aaaaaaaa.o3d'
+  who's contents is 'o3d'. This is to prevent O3D being used to open
+  archive files that were not meant for it.
+
+  \code
+  var request = pack.createArchiveRequest();
+  request.open("GET", url);
+
+  request.onfileavailable = myFileAvailableCallback;
+  request.onreadystatechange = myReadyStateChangeCallback;
+  request.send();
+
+  function myFileAvailableCallback(rawData) {
+    dump("uri: " + rawData.uri + "\n");
+    dump("content: " + rawData.stringValue + "\n");
+
+    // You can pass a RawData to various creation functions. Note: rawData
+    // is only valid until you remove the request.
+    // Examples:
+    if (rawData.uri == 'mytexture.jpg')
+      pack.createTexture2d(rawData, makeMips);
+    if (rawData.uri == 'myvertices.bin')
+      vertexBuffer.set(rawData);
+    if (rawData.uri == 'myAudio.mp3')
+      audioSystem.createSound(rawData);
+  }
+
+  function myReadyStateChangeCallback() {
+    if (request.done) {
+      if (request.success) {
+        // there were no errors trying to read the archive
+      } else {
+        dump(request.error);
+      }
+    }
+  }
+
+  // When you are done with the RawDatas loaded by the request, remove
+  // the request from the pack to free them.
+  pack.removeObject(request);
+*/
+
+o3d.ArchiveRequest = function() {
+  o3d.ObjectBase.call(this);
+  this.method_ = null;
+};
+o3d.inherit('ArchiveRequest', 'ObjectBase');
+
+/**
+ * The URI this request is for.
+ * @type {string}
+ */
+o3d.ArchiveRequest.prototype.uri = '';
+
+/**
+ * Set up several of the request fields.
+ * @param {string} method "GET" is the only supported method at this time
+ * @param {string} uri the location of the file to fetch
+ * @param {boolean} async true is the only legal value at this time.
+ */
+o3d.ArchiveRequest.prototype.open =
+    function(method, uri) {
+  this.uri = uri;
+
+  // Compute the parent directory of this URI.
+  var parentURI = uri;
+  var lastSlash = uri.lastIndexOf('/');
+  if (lastSlash != -1) {
+    parentURI = parentURI.substring(0, lastSlash + 1);
+  }
+
+  this.parentURI_ = parentURI;
+};
+
+/**
+ * Send the request.
+ * Unlike XMLHttpRequest the onreadystatechange callback will be called no
+ * matter what, with success or failure.
+ */
+o3d.ArchiveRequest.prototype.send = function() {
+  var that = this;
+  this.done = false;
+  this.success = true;
+  this.error = null;
+  var callback = function(sourceJSON, exc) {
+    // Don't send down the original scene.json because 'eval' is used
+    // elsewhere to reconstitute it, which is risky.
+    var filteredJSON = JSON.stringify(JSON.parse(sourceJSON));
+
+    if (that.onfileavailable) {
+      var rawData = new o3d.RawData();
+      rawData.uri = 'scene.json';
+      rawData.stringValue = filteredJSON;
+      that.onfileavailable(rawData);
+    }
+
+    // In o3d-webgl, the "archive" is really just the top-level
+    // scene.json. We run a regexp on it to find URIs for certain
+    // well-known file types (.fx, .png, .jpg) and issue file requests
+    // for them.
+    var uriRegex = /\"([^\"]*\.(fx|png|jpg))\"/g;
+    var matchArray;
+    var uris = [];
+    while ((matchArray = uriRegex.exec(sourceJSON)) != null) {
+      uris.push(matchArray[1]);
+    }
+
+    that.pendingRequests_ = uris.length;
+
+    // Issue requests for each of these URIs.
+    for (var ii = 0; ii < uris.length; ++ii) {
+      if (that.stringEndsWith_(uris[ii], ".fx")) {
+        var func = function(uri) {
+          var completion = function(value, exc) {
+            var rawData = null;
+            if (exc == null) {
+              rawData = new o3d.RawData();
+              rawData.uri = uri;
+              rawData.stringValue = value;
+            }
+            that.decrementPendingRequests_(rawData, exc);
+          };
+          o3djs.io.loadTextFile(that.relativeToAbsoluteURI_(uri),
+                                completion);
+        };
+        func(uris[ii]);
+      } else if (that.stringEndsWith_(uris[ii], ".png") ||
+                 that.stringEndsWith_(uris[ii], ".jpg")) {
+        var func = function(uri) {
+          var image = new Image();
+          image.onload = function() {
+            var rawData = new o3d.RawData();
+            rawData.uri = uri;
+            rawData.image_ = image;
+            that.decrementPendingRequests_(rawData, exc);
+          };
+          image.onerror = function() {
+            that.decrementPendingRequests_(null, exc);
+          }
+          image.src = that.relativeToAbsoluteURI_(uri);
+        };
+        func(uris[ii]);
+      }
+    }
+  };
+
+  o3djs.io.loadTextFile(this.uri, callback);
+};
+
+/**
+ * A callback to call whenever the ready state of the request changes.
+ * @type {function(): void}
+ */
+o3d.ArchiveRequest.prototype.onreadystatechange = null;
+
+/**
+ * A callback to call when each file comes in.
+ * @type {function(!o3d.RawData): void}
+ */
+o3d.ArchiveRequest.prototype.onfileavailable = null;
+
+/**
+ * Converts a local URI to an absolute URI.
+ * @private
+ */
+o3d.ArchiveRequest.prototype.relativeToAbsoluteURI_ = function(relativeURI) {
+  return this.parentURI_ + relativeURI;
+};
+
+/**
+ * Indicates whether one string ends with another.
+ * @private
+ */
+o3d.ArchiveRequest.prototype.stringEndsWith_ = function(string, suffix) {
+  return string.substring(string.length - suffix.length) == suffix;
+};
+
+/**
+ * Decrements the number of pending requests.
+ * @private
+ */
+o3d.ArchiveRequest.prototype.decrementPendingRequests_ =
+    function(rawData, opt_exc) {
+  this.success = this.success && rawData && (!opt_exc);
+  if (opt_exc != null) {
+    this.error = "" + opt_exc;
+  }
+  if (rawData && this.onfileavailable) {
+    this.onfileavailable(rawData);
+  }
+  if (--this.pendingRequests_ == 0) {
+    this.done = true;
+    if (this.onreadystatechange) {
+      this.onreadystatechange();
+    }
+  }
+};