Merge pull request #11293 from adobe/marcel/scroll-marks-fixes

Improve search tick mark positioning

Author: Marcel Gerber

src/search/ScrollTrackMarkers.js

@@ -67,8 +67,43 @@ define(function (require, exports, module) {
      * @type {?jQueryObject}
      */
     var $markedTickmark;
+    
+    /**
+     * Vertical space above and below the scrollbar
+     * @type {number}
+     */
+    var scrollbarTrackOffset;
+
+    switch (brackets.platform) {
+    case "win": // Custom scrollbar CSS has no gap around the track
+        scrollbarTrackOffset = 0;
+        break;
+    case "mac": // Native scrollbar has padding around the track
+        scrollbarTrackOffset = 4;
+        break;
+    case "linux": // Custom scrollbar CSS has assymmetrical gap; this approximates it
+        scrollbarTrackOffset = 2;
+        break;
+    }
 
+    /**
+     * Vertical space above and below the scrollbar.
+     * @return {number} amount Value in pixels
+     */
+    function getScrollbarTrackOffset() {
+        return scrollbarTrackOffset;
+    }
 
+    /**
+     * Sets how much vertical space there's above and below the scrollbar, which depends
+     * on the OS and may also be affected by extensions
+     * @param {number} offset Value in pixels
+     */
+    function setScrollbarTrackOffset(offset) {
+        scrollbarTrackOffset = offset;
+    }
+    
+    
     function _getScrollbar(editor) {
         // Be sure to select only the direct descendant, not also elements within nested inline editors
         return $(editor.getRootElement()).children(".CodeMirror-vscrollbar");
@@ -81,16 +116,8 @@ define(function (require, exports, module) {
         trackHt = $sb[0].offsetHeight;
 
         if (trackHt > 0) {
-            // Scrollbar visible: determine offset of track from top of scrollbar
-            if (brackets.platform === "win") {
-                trackOffset = 0;  // Custom scrollbar CSS has no gap around the track
-            } else if (brackets.platform === "mac") {
-                trackOffset = 4;  // Native scrollbar has padding around the track
-            } else { //(Linux)
-                trackOffset = 2;  // Custom scrollbar CSS has assymmetrical gap; this approximates it
-            }
+            trackOffset = getScrollbarTrackOffset();
             trackHt -= trackOffset * 2;
-
         } else {
             // No scrollbar: use the height of the entire code content
             var codeContainer = $(editor.getRootElement()).find("> .CodeMirror-scroll > .CodeMirror-sizer > div > .CodeMirror-lines > div")[0];
@@ -101,9 +128,31 @@ define(function (require, exports, module) {
 
     /** Add all the given tickmarks to the DOM in a batch */
     function _renderMarks(posArray) {
-        var html = "";
+        var html = "",
+            cm = editor._codeMirror,
+            editorHt = cm.getScrollerElement().scrollHeight;
+
+        // We've pretty much taken these vars and the getY function from CodeMirror's annotatescrollbar addon
+        // https://github.com/codemirror/CodeMirror/blob/master/addon/scroll/annotatescrollbar.js
+        var wrapping = cm.getOption("lineWrapping"),
+            singleLineH = wrapping && cm.defaultTextHeight() * 1.5,
+            curLine = null,
+            curLineObj = null;
+
+        function getY(cm, pos) {
+            if (curLine !== pos.line) {
+                curLine = pos.line;
+                curLineObj = cm.getLineHandle(curLine);
+            }
+            if (wrapping && curLineObj.height > singleLineH) {
+                return cm.charCoords(pos, "local").top;
+            }
+            return cm.heightAtLine(curLineObj, "local");
+        }
+
         posArray.forEach(function (pos) {
-            var top = Math.round(pos.line / editor.lineCount() * trackHt) + trackOffset;
+            var cursorTop = getY(cm, pos),
+                top = Math.round(cursorTop / editorHt * trackHt) + trackOffset;
             top--;  // subtract ~1/2 the ht of a tickmark to center it on ideal pos
 
             html += "<div class='tickmark' style='top:" + top + "px'></div>";
@@ -140,8 +189,8 @@ define(function (require, exports, module) {
                 return;
             }
 
-            var $sb = _getScrollbar(editor);
-            var $overlay = $("<div class='tickmark-track'></div>");
+            var $sb = _getScrollbar(editor),
+                $overlay = $("<div class='tickmark-track'></div>");
             $sb.parent().append($overlay);
 
             _calcScaling();
@@ -201,4 +250,7 @@ define(function (require, exports, module) {
     exports.setVisible      = setVisible;
     exports.addTickmarks    = addTickmarks;
     exports.markCurrent     = markCurrent;
+    
+    exports.getScrollbarTrackOffset = getScrollbarTrackOffset;
+    exports.setScrollbarTrackOffset = setScrollbarTrackOffset;
 });