Created a setting for the number of out-of-view rows buffered for thumbnails

diff --git a/GnuBook/GnuBook.js b/GnuBook/GnuBook.js
index 8b4714f..64bffee 100644 (file)
--- a/GnuBook/GnuBook.js
+++ b/GnuBook/GnuBook.js
@@ -41,6 +41,7 @@ function GnuBook() {
     this.mode    = 1; //1, 2, 3
     this.ui = 'full'; // UI mode
     this.thumbScale = 10; // thumbnail default
+       this.thumbRowBuffer = 4; // number of rows to pre-cache out a view
 
     this.displayedIndices = [];        
        this.displayedRows=[];
@@ -633,8 +634,7 @@ GnuBook.prototype.drawLeafsThumbnail = function() {
        
        var firstRow = rowsToDisplay[0];
        var lastRow = rowsToDisplay[rowsToDisplay.length-1];
-       var rowBuffer = 4;
-       for (i=1; i<rowBuffer+1; i++) {
+       for (i=1; i<this.thumbRowBuffer+1; i++) {
                if (firstRow-i >= 0) { rowsToDisplay.unshift(firstRow-i); }
                if (lastRow+i < leafMap.length) { rowsToDisplay.push(lastRow+i); }
        }