From a64e3c1d3ef4055d382f052396ba2dfae8f1981e Mon Sep 17 00:00:00 2001
From: Andreas Hocevar <andreas.hocevar@gmail.com>
Date: Wed, 13 Jul 2016 14:23:41 +0200
Subject: [PATCH] Add renderBuffer option for ol.source.ImageVector

---
 externs/olx.js                     | 12 ++++++++++++
 src/ol/source/imagevectorsource.js |  8 +++++++-
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/externs/olx.js b/externs/olx.js
index 5fe169fb10..31060381b0 100644
--- a/externs/olx.js
+++ b/externs/olx.js
@@ -4970,6 +4970,7 @@ olx.source.ImageCanvasOptions.prototype.state;
  *     logo: (string|olx.LogoOptions|undefined),
  *     projection: ol.ProjectionLike,
  *     ratio: (number|undefined),
+ *     renderBuffer: (number|undefined),
  *     resolutions: (Array.<number>|undefined),
  *     source: ol.source.Vector,
  *     style: (ol.style.Style|Array.<ol.style.Style>|ol.StyleFunction|undefined)}}
@@ -5011,6 +5012,17 @@ olx.source.ImageVectorOptions.prototype.projection;
 olx.source.ImageVectorOptions.prototype.ratio;
 
 
+/**
+ * The buffer around the viewport extent used by the renderer when getting
+ * features from the vector source for the rendering or hit-detection.
+ * Recommended value: the size of the largest symbol, line width or label.
+ * Default is 100 pixels.
+ * @type {number|undefined}
+ * @api
+ */
+olx.source.ImageVectorOptions.prototype.renderBuffer;
+
+
 /**
  * Resolutions. If specified, new canvases will be created for these resolutions
  * only.
diff --git a/src/ol/source/imagevectorsource.js b/src/ol/source/imagevectorsource.js
index f7e9324523..3c8287236c 100644
--- a/src/ol/source/imagevectorsource.js
+++ b/src/ol/source/imagevectorsource.js
@@ -56,6 +56,12 @@ ol.source.ImageVector = function(options) {
    */
   this.canvasSize_ = [0, 0];
 
+  /**
+   * @private
+   * @type {number}
+   */
+  this.renderBuffer_ = options.renderBuffer == undefined ? 100 : options.renderBuffer;
+
   /**
    * @private
    * @type {ol.render.canvas.ReplayGroup}
@@ -108,7 +114,7 @@ ol.source.ImageVector.prototype.canvasFunctionInternal_ = function(extent, resol
 
   var replayGroup = new ol.render.canvas.ReplayGroup(
       ol.renderer.vector.getTolerance(resolution, pixelRatio), extent,
-      resolution);
+      resolution, this.renderBuffer_);
 
   this.source_.loadFeatures(extent, resolution, projection);