diff --git a/lib/torque/renderer/ball.js b/lib/torque/renderer/ball.js
index 817be75..69134f9 100644
--- a/lib/torque/renderer/ball.js
+++ b/lib/torque/renderer/ball.js
@@ -275,7 +275,7 @@ BallRenderer.prototype = {
         for (var i = 0, len = this.pointLayer.length; i< len; i+=4){
             alpha = this.pointLayer[i+3] * 4; // get gradient color from opacity value
 
-            if (alpha) {
+            if (alpha>0) {
                 this.heatmapLayer[i] = grad[alpha]; // R
                 this.heatmapLayer[i + 1] = grad[alpha + 1]; // G
                 this.heatmapLayer[i + 2] = grad[alpha + 2]; // B