diff --git a/lib/ace/document.js b/lib/ace/document.js
index 9766763d..bf30aa3b 100644
--- a/lib/ace/document.js
+++ b/lib/ace/document.js
@@ -895,9 +895,13 @@ var Document = function(text, mode) {
             else {
                 var lenBefore = value.length;
                 value = value.trimLeft();
+
                 // True if value has some content. This content goes directly
                 // after the last split.
-                if (value.length != 0) {
+                // If there is no content but we are in the last tabLine, we
+                // already know that there is no following tabLine and we can
+                // shortcut by using this if instead of the following else.
+                if (value.length != 0 || i == tabLine.length - 1) {
                     documentColumn = lastSplitColumn += lenBefore - value.length;
                     screenColumn += value.length;
                     documentColumn += 1; // The tab after this for-loop.
@@ -974,28 +978,7 @@ var Document = function(text, mode) {
     };
 
     this.screenToDocumentColumn = function(row, screenColumn) {
-        var tabSize = this.getTabSize();
-
-        var docColumn = 0;
-        var remaining = screenColumn;
-
-        var line = this.getLine(row).split("\t");
-        for (var i=0; i<line.length; i++) {
-            var len = line[i].length;
-            if (remaining >= len + tabSize) {
-                remaining -= (len + tabSize);
-                docColumn += (len + 1);
-            }
-            else if (remaining > len){
-                docColumn += len;
-                break;
-            }
-            else {
-                docColumn += remaining;
-                break;
-            }
-        }
-        return docColumn;
+        return this.screenToDocumentPosition(row, screenColumn).column;
     };
 
     this.screenToDocumentRow = function(row) {
@@ -1014,24 +997,50 @@ var Document = function(text, mode) {
     };
 
     this.screenToDocumentPosition = function(row, column) {
+        var line;
+        var docRow;
+        var docColumn;
+        var remaining = column;
         if (!this.$useWrapMode) {
-            return {
-                row: row,
-                column: this.screenToDocumentColumn(row, column)
+            docRow = row;
+            docColumn = 0;
+            line = this.getLine(docRow).split("\t");
+        } else {
+            var wrapData = this.$wrapData, linesCount = this.lines.length;
+
+            docRow = 0;
+            while (docRow < linesCount && row >= wrapData[docRow].length + 1) {
+                row -= wrapData[docRow].length + 1;
+                docRow ++;
+            }
+
+            if (docRow >= this.lines.length) {
+                return {
+                    row: docRow,
+                    column: 0
+                };
+            }
+            docColumn = wrapData[docRow][row - 1] || 0;
+            line = this.getLine(docRow).substring(docColumn).split("\t");
+        }
+
+        var tabSize = this.getTabSize();
+        for (var i=0; i<line.length; i++) {
+            var len = line[i].length;
+            if (remaining >= len + tabSize) {
+                remaining -= (len + tabSize);
+                docColumn += (len + 1);
+            }
+            else if (remaining > len){
+                docColumn += len;
+                break;
+            }
+            else {
+                docColumn += remaining;
+                break;
             }
         }
 
-        var wrapData = this.$wrapData, linesCount = this.lines.length;
-
-        var docRow = 0;
-        while (docRow < linesCount && row >= wrapData[docRow].length + 1) {
-            row -= wrapData[docRow].length + 1;
-            docRow ++;
-        }
-
-        var docColumn = column +
-            (docRow < linesCount ? wrapData[docRow][row - 1] || 0 : 0);
-
         // Clamp docColumn.
         if (docRow < linesCount && wrapData[docRow][row]) {
             docColumn =  Math.min(docColumn, wrapData[docRow][row]);
@@ -1046,25 +1055,7 @@ var Document = function(text, mode) {
     };
 
     this.documentToScreenColumn = function(row, docColumn) {
-        var tabSize = this.getTabSize();
-
-        var screenColumn = 0;
-        var remaining = docColumn;
-
-        var line = this.getLine(row).split("\t");
-        for (var i=0; i<line.length; i++) {
-            var len = line[i].length;
-            if (remaining > len) {
-                remaining -= (len + 1);
-                screenColumn += len + tabSize;
-            }
-            else {
-                screenColumn += remaining;
-                break;
-            }
-        }
-
-        return screenColumn;
+        return this.documentToScreenPosition(row, docColumn).column;
     };
 
     this.documentToScreenRow = function(row) {
@@ -1091,16 +1082,28 @@ var Document = function(text, mode) {
     }
 
     this.documentToScreenPosition = function(row, column) {
+        var str;
+        var tabSize = this.getTabSize();
+
         if (!this.$useWrapMode) {
+            str = this.getLine(row).substring(0, column);
+            column += (str.split("\t").length - 1) * (tabSize - 1);
             return {
                 row: row,
-                column: this.documentToScreenColumn(row, column)
-            }
+                column: column
+            };
         }
         var screenRow = this.documentToScreenRow(row);
+        if (row >= this.lines.length) {
+            return {
+                row: screenRow,
+                column: 0
+            };
+        }
         var screenColumn = column;
         var wrapRowData = this.$wrapData[row];
-        for (var split = 0; wrapRowData && split < wrapRowData.length; split++) {
+        var split;
+        for (split = 0; wrapRowData && split < wrapRowData.length; split++) {
             if (column > wrapRowData[split]) {
                 screenColumn = column - wrapRowData[split];
                 screenRow ++;
@@ -1109,6 +1112,9 @@ var Document = function(text, mode) {
             }
         }
 
+        str = this.getLine(row).substring(wrapRowData[split - 1] || 0,  column);
+        screenColumn += (str.split("\t").length - 1) * (tabSize - 1);
+
         return {
             row: screenRow,
             column: screenColumn
diff --git a/lib/ace/layer/cursor.js b/lib/ace/layer/cursor.js
index 30a52de7..9791ffb8 100644
--- a/lib/ace/layer/cursor.js
+++ b/lib/ace/layer/cursor.js
@@ -58,10 +58,8 @@ var Cursor = function(parentEl) {
     };
 
     this.setCursor = function(position, overwrite) {
-        this.position = {
-            row : position.row,
-            column : this.doc.documentToScreenColumn(position.row, position.column)
-        };
+        this.position =
+            this.doc.documentToScreenPosition(position.row, position.column);
         if (overwrite) {
             dom.addCssClass(this.cursor, "ace_overwrite");
         } else {
@@ -109,8 +107,7 @@ var Cursor = function(parentEl) {
             };
         }
 
-        var pos = this.doc.documentToScreenPosition(this.position.row,
-                                                    this.position.column);
+        var pos = this.position;
         var cursorLeft = Math.round(pos.column * this.config.characterWidth);
         var cursorTop = (pos.row - (onScreen ? this.config.firstRowScreen : 0)) *
             this.config.lineHeight;