Cycles :

* Use is_zero(a) rather than dot(a, a) == 0, saves some calculations. 

1 files changed, 1 insertions, 1 deletions

diff --git a/intern/cycles/kernel/kernel_camera.h b/intern/cycles/kernel/kernel_camera.h
index 8bd09247339..a23586a53a4 100644
--- a/intern/cycles/kernel/kernel_camera.h
+++ b/intern/cycles/kernel/kernel_camera.h
@@ -187,7 +187,7 @@ __device void camera_sample_panorama(KernelGlobals *kg, float raster_x, float ra
 	}
 
 	/* indicates ray should not receive any light, outside of the lens */
-	if(len_squared(ray->D) == 0.0f) {
+	if(is_zero(ray->D)) {	
 		ray->t = 0.0f;
 		return;
 	}