diff --git a/lib/ace/edit_session.js b/lib/ace/edit_session.js
index 6ccb6a91..ed84f009 100644
--- a/lib/ace/edit_session.js
+++ b/lib/ace/edit_session.js
@@ -944,13 +944,14 @@ var EditSession = function(text, mode) {
 
     this.$getDisplayTokens = function(str) {
         var arr = [];
-        var tabSize = this.getTabSize();
+        var tabSize;
 
         for (var i = 0; i < str.length; i++) {
 			var c = str.charCodeAt(i);
 			// Tab
 			if (c == 9) {
 			    arr.push(TAB);
+                tabSize = this.getScreenTabSize(arr.length);
 			    for (var n = 1; n < tabSize; n++) {
 			        arr.push(TAB_SPACE);
 			    }
@@ -990,7 +991,7 @@ var EditSession = function(text, mode) {
 			var c = str.charCodeAt(i);
 			// tab
 			if (c == 9) {
-				screenColumn += tabSize;
+				screenColumn += this.getScreenTabSize(screenColumn);
 			}
     		// CJK characters
             else if (
@@ -1103,6 +1104,13 @@ var EditSession = function(text, mode) {
         return this.screenToDocumentPosition(screenRow, screenColumn).column;
     };
 
+    /**
+     * Returns the width of a tab character at screenColumn.
+     */
+    this.getScreenTabSize = function(screenColumn) {
+        return this.$tabSize - screenColumn % this.$tabSize;
+    };
+
     this.screenToDocumentPosition = function(row, column) {
         var line;
         var docRow;
@@ -1131,7 +1139,8 @@ var EditSession = function(text, mode) {
             line = this.getLine(docRow).substring(docColumn);
         }
 
-        var tabSize = this.getTabSize();
+        var tabSize,
+            screenColumn = 0;
         for(var i = 0; i < line.length; i++) {
             var c = line.charCodeAt(i);
 
@@ -1139,8 +1148,10 @@ var EditSession = function(text, mode) {
                 docColumn += 1;
                 // tab
                 if (c == 9) {
+                    tabSize = this.getScreenTabSize(screenColumn);
                     if (remaining >= tabSize) {
                         remaining -= tabSize;
+                        screenColumn += tabSize;
                     } else {
                         remaining = 0;
                         docColumn -= 1;
@@ -1154,6 +1165,7 @@ var EditSession = function(text, mode) {
                     c >= 0xF900 && c <= 0xFAFF ||
                     c >= 0x3400 && c <= 0x4DBF
                 ) {
+                    screenColumn += 2;
                     if (remaining >= 2) {
                         remaining -= 2;
                     } else {
@@ -1161,6 +1173,7 @@ var EditSession = function(text, mode) {
                         docColumn -= 1;
                     }
                 } else {
+                    screenColumn += 2;
                     remaining -= 1;
                 }
             } else {
diff --git a/lib/ace/layer/text.js b/lib/ace/layer/text.js
index 43f24baa..7c22548f 100644
--- a/lib/ace/layer/text.js
+++ b/lib/ace/layer/text.js
@@ -160,18 +160,21 @@ var Text = function(parentEl) {
         return true;
     };
 
+    this.$tabStrings = [];
     this.$computeTabString = function() {
         var tabSize = this.session.getTabSize();
-        if (this.showInvisibles) {
-            var halfTab = (tabSize) / 2;
-            this.$tabString = "<span class='ace_invisible'>"
-                + new Array(Math.floor(halfTab)).join("&#160;")
-                + this.TAB_CHAR
-                + new Array(Math.ceil(halfTab)+1).join("&#160;")
-                + "</span>";
-        } else {
-            this.$tabString = new Array(tabSize+1).join("&#160;");
+        var tabStr = this.$tabStrings = [0];
+        for (var i = 1; i < tabSize + 1; i++) {
+            if (this.showInvisibles) {
+                tabStr.push("<span class='ace_invisible'>"
+                    + this.TAB_CHAR
+                    + new Array(i).join("&#160;")
+                    + "</span>");
+            } else {
+                tabStr.push(new Array(i+1).join("&#160;"));
+            }
         }
+
     };
 
     this.updateLines = function(config, firstRow, lastRow) {
@@ -295,17 +298,41 @@ var Text = function(parentEl) {
             var spaceReplace = "&#160;";
         }
 
-        var _self = this;
-        var characterWidth = this.config.characterWidth;
+        var _self = this,
+            characterWidth = this.config.characterWidth,
+            screenColumn = 0;
+
         function addToken(token, value) {
             var output = value
-                .replace(/&/g, "&amp;")
-                .replace(/</g, "&lt;")
+                    .replace(/\t|&|<|[\u3040-\u309F]|[\u30A0-\u30FF]|[\u4E00-\u9FFF\uF900-\uFAFF\u3400-\u4DBF]/g, function(c, idx) {
+                        if (c == "\t") {
+                            var tabSize = _self.session.
+                                    getScreenTabSize(screenColumn + idx);
+                            screenColumn += tabSize - 1;
+                            return _self.$tabStrings[tabSize];
+                        } else if (c == "&") {
+                            return "&amp";
+                        } else if (c == "<") {
+                            return "&lt;";
+                        } else {
+                            screenColumn += 1;
+                            return "<span class='ace_cjk' style='width:" + (characterWidth * 2) + "px'>" + c + "</span>"
+                        }
+                    })
+//                .replace(/\t/g, function(c, idx) {
+//                    idx += screenColumnOld;
+//                    var tabSize = _self.session.getScreenTabSize(idx);
+//                    screenColumn += tabSize - 1;
+//                    return _self.$tabStrings[tabSize];
+//                })
+//                .replace(/&/g, "&amp;")
+//                .replace(/</g, "&lt;")
                 .replace(spaceRe, spaceReplace)
-                .replace(/\t/g, _self.$tabString)
-                .replace(/[\u3040-\u309F]|[\u30A0-\u30FF]|[\u4E00-\u9FFF\uF900-\uFAFF\u3400-\u4DBF]/g, function(c) {
-                    return "<span class='ace_cjk' style='width:" + (characterWidth * 2) + "px'>" + c + "</span>"
-                });
+//                .replace(/[\u3040-\u309F]|[\u30A0-\u30FF]|[\u4E00-\u9FFF\uF900-\uFAFF\u3400-\u4DBF]/g, function(c) {
+//                    screenColumn += 1;
+//                    return "<span class='ace_cjk' style='width:" + (characterWidth * 2) + "px'>" + c + "</span>"
+//                });
+                screenColumn += value.length;
 
             if (!_self.$textToken[token.type]) {
                 var classes = "ace_" + token.type.replace(/\./g, " ace_");
@@ -344,7 +371,9 @@ var Text = function(parentEl) {
                         "<div style='height:",
                         this.config.lineHeight, "px",
                         "'>");
+
                     split ++;
+                    screenColumn = 0;
                     splitChars = splits[split] || Number.MAX_VALUE;
                 }
                 if (value.length != 0) {