diff --git a/src/core/renderers/webgl/filters/Filter.js b/src/core/renderers/webgl/filters/Filter.js
index 36560a9..16b2cec 100644
--- a/src/core/renderers/webgl/filters/Filter.js
+++ b/src/core/renderers/webgl/filters/Filter.js
@@ -1,4 +1,7 @@
-var extractUniformsFromSrc = require('./extractUniformsFromSrc');
+var extractUniformsFromSrc = require('./extractUniformsFromSrc'),
+    utils = require('../../../utils'),
+    SOURCE_KEY_MAP = {};
+
 // var math = require('../../../math');
 /**
  * @class
@@ -38,20 +41,24 @@
         this.uniforms[i] = this.uniformData[i].value;
     }
 
-    // this.uniforms =
     // this is where we store shader references..
     // TODO we could cache this!
     this.glShaders = [];
 
-    // used for cacheing..
-    this.glShaderKey = null;
+    // used for cacheing.. sure there is a better way!
+    if(!SOURCE_KEY_MAP[this.vertexSrc + this.fragmentSrc])
+    {
+        SOURCE_KEY_MAP[this.vertexSrc + this.fragmentSrc] = utils.uid();
+    }
+
+    this.glShaderKey = SOURCE_KEY_MAP[this.vertexSrc + this.fragmentSrc];
 
     this.padding = 4;
     this.resolution = 1;
 }
 
 // constructor
-Filter.prototype.constructor = Filter;
+//Filter.prototype.constructor = Filter;
 module.exports = Filter;
 
 // var tempMatrix = new math.Matrix();