Added internal.getPageInfo method to get objId of page

Author: Flamenco

jspdf.js

@@ -963,7 +963,11 @@ var jsPDF = (function(global) {
 			'getNumberOfPages' : function() {
 				return pages.length - 1;
 			},
-			'pages' : pages
+			'pages' : pages,
+			'getPageInfo' : function(pageNumberOneBased){
+				var objId = (pageNumberOneBased - 1) * 2 + 3;
+				return {objId:objId};
+			}
 		};
 
 		/**

jspdf.plugin.annotations.js

@@ -109,8 +109,8 @@
 						line = '<</Type /Annot /Subtype /Link ' + rect + '/Border [0 0 0] /A <</S /URI /URI (' + anno.options.url + ') >>';
 					} else if (anno.options.pageNumber) {
 						// first page is 0
-						var pageObjId = anno.options.pageNumber * 2 + 1;
-						line = '<</Type /Annot /Subtype /Link ' + rect + '/Border [0 0 0] /Dest [' + pageObjId + " 0 R";
+						var info = this.internal.getPageInfo(anno.options.pageNumber);
+						line = '<</Type /Annot /Subtype /Link ' + rect + '/Border [0 0 0] /Dest [' + info.objId + " 0 R";
 						anno.options.magFactor = anno.options.magFactor || "XYZ";
 						switch (anno.options.magFactor) {
 						case 'Fit':

jspdf.plugin.outline.js

@@ -56,7 +56,8 @@
 					for (var i = 0; i < totalPages; i++) {
 						var id = pdf.internal.newObject();
 						dests.push(id);
-						pdf.internal.write("<< /D[" + (i * 2 + 3) + " 0 R /XYZ null null null]>> endobj");
+						var info = pdf.internal.getPageInfo(i+1);
+						pdf.internal.write("<< /D[" + info.objId + " 0 R /XYZ null null null]>> endobj");
 					}
 
 					// assign a name for each destination
@@ -185,7 +186,8 @@
 							if (item.options.pageNumber) {
 								// Explicit Destination
 								//WARNING this assumes page ids are 3,5,7, etc.
-								this.line('/Dest ' + '[' + ((item.options.pageNumber - 1) * 2 + 3) + ' 0 R /XYZ 0 ' + this.ctx.pdf.internal.pageSize.height + ' 0]');
+								var info = pdf.internal.getPageInfo(item.options.pageNumber)
+								this.line('/Dest ' + '[' + info.objId + ' 0 R /XYZ 0 ' + this.ctx.pdf.internal.pageSize.height + ' 0]');
 								// this line does not work on all clients (pageNumber instead of page ref)
 								//this.line('/Dest ' + '[' + (item.options.pageNumber - 1) + ' /XYZ 0 ' + this.ctx.pdf.internal.pageSize.height + ' 0]');