diff --git a/zenovis/xinxinoptix/DeflMatShader.cu b/zenovis/xinxinoptix/DeflMatShader.cu
index 91c7ddf250..4f9787ded1 100644
--- a/zenovis/xinxinoptix/DeflMatShader.cu
+++ b/zenovis/xinxinoptix/DeflMatShader.cu
@@ -237,9 +237,9 @@ extern "C" __global__ void __anyhit__shadow_cutout()
     bv0 = meshMat * bv0;
     bv1 = meshMat * bv1;
     bv2 = meshMat * bv2;
-    float3 v0 = make_float3(bv0.x, bv0.y, bv0.z);
-    float3 v1 = make_float3(bv1.x, bv1.y, bv1.z);
-    float3 v2 = make_float3(bv2.x, bv2.y, bv2.z);
+    float3& v0 = *(float3*)&bv0; //make_float3(bv0.x, bv0.y, bv0.z);
+    float3& v1 = *(float3*)&bv1; //make_float3(bv1.x, bv1.y, bv1.z);
+    float3& v2 = *(float3*)&bv2; //make_float3(bv2.x, bv2.y, bv2.z);
 
     float3 N_0 = normalize( cross( normalize(v1-v0), normalize(v2-v0) ) );
 
@@ -509,9 +509,9 @@ extern "C" __global__ void __closesthit__radiance()
     bv0 = meshMat * bv0;
     bv1 = meshMat * bv1;
     bv2 = meshMat * bv2;
-    float3 v0 = make_float3(bv0.x, bv0.y, bv0.z);
-    float3 v1 = make_float3(bv1.x, bv1.y, bv1.z);
-    float3 v2 = make_float3(bv2.x, bv2.y, bv2.z);
+    float3& v0 = *(float3*)&bv0; //make_float3(bv0.x, bv0.y, bv0.z);
+    float3& v1 = *(float3*)&bv1; //make_float3(bv1.x, bv1.y, bv1.z);
+    float3& v2 = *(float3*)&bv2; //make_float3(bv2.x, bv2.y, bv2.z);
 
     float3 N_0 = normalize( cross( normalize(v1-v0), normalize(v2-v1) ) ); // this value has precision issue for big float 
     
diff --git a/zenovis/xinxinoptix/Light.h b/zenovis/xinxinoptix/Light.h
index c0f0e452f8..3f22a211f8 100644
--- a/zenovis/xinxinoptix/Light.h
+++ b/zenovis/xinxinoptix/Light.h
@@ -256,7 +256,7 @@ void DirectLighting(RadiancePRD *prd, RadiancePRD& shadow_prd, const float3& sha
             
             light_attenuation = shadow_prd.shadowAttanuation;
 
-            if (length(light_attenuation) > 0.0f) {
+            if (lengthSquared(light_attenuation) > 0.0f) {
                 
                 auto bxdf_value = evalBxDF(lsr.dir, wo, scatterPDF);
                 auto misWeight = 1.0f;
diff --git a/zenovis/xinxinoptix/Shape.h b/zenovis/xinxinoptix/Shape.h
index 16b8a78426..56e3e042f1 100644
--- a/zenovis/xinxinoptix/Shape.h
+++ b/zenovis/xinxinoptix/Shape.h
@@ -247,6 +247,8 @@ struct SphereShape {
 
         float3 f = ray_origin - center;
         float b2 = dot(f, ray_dir);
+        if (b2 >= 0) { return false; }
+
 		float r2 = radius * radius;
 
 		float3 fd = f - b2 * ray_dir;
@@ -264,7 +266,6 @@ struct SphereShape {
             lsr->dir = ray_dir;
             lsr->dist = fminf(c/q, q);
             lsr->p = ray_origin + ray_dir * lsr->dist;
-
             // lsr->n = normalize(lsr->p - center);
             // lsr->p = rtgems::offset_ray(lsr->p, lsr->n);
             // lsr->dist = length(lsr->p - ray_origin);