diff --git a/shaders/compute.glsl b/shaders/compute.glsl
index a17020b..febe279 100644
--- a/shaders/compute.glsl
+++ b/shaders/compute.glsl
@@ -202,8 +202,8 @@ vec3 pathtrace(Ray ray, inout uint rng_state)
         GPUMaterial mat = materials[hit.mat_index];
         calculateLightColor(mat, hit, color, light, rng_state);
         
-		// if (mat.emission > 0.0 && mat.emission_texture_index == -1)
-		// 	break;
+		if (mat.emission > 0.0 && mat.emission_texture_index == -1)
+			break;
 
         ray = newRay(hit, ray, rng_state);
         ray.inv_direction = 1.0 / ray.direction;
diff --git a/shaders/intersect.glsl b/shaders/intersect.glsl
index b62ce3d..543ca42 100644
--- a/shaders/intersect.glsl
+++ b/shaders/intersect.glsl
@@ -1,27 +1,28 @@
 bool intersectSphere(Ray ray, GPUObject obj, out hitInfo hit)
 {
 	vec3 oc = ray.origin - obj.position;
-	
 	float b = dot(oc, ray.direction);
 	float c = dot(oc, oc) - obj.radius * obj.radius;
-	float h = b * b - c;
-	
-	float t = -b - sqrt(h);
-	float last_t = -b + sqrt(h);
+	float discriminant = b * b - c;
 
-	if (t > last_t)
-	{
-		float temp = t;
-		t = last_t;
-		last_t = temp;
-	}
+	float sqrtD = sqrt(max(0.0, discriminant));
+	float t0 = -b - sqrtD;
+	float t1 = -b + sqrtD;
 
-	hit.t = t;
-	hit.last_t = last_t;
-	hit.position = ray.origin + ray.direction * t;
+	float temp = min(t0, t1);
+	t1 = max(t0, t1);
+	t0 = temp;
+
+	bool isInside = c < 0.0;
+	t0 = isInside ? t1 : t0;
+
+	hit.t = t0;
+	hit.last_t = t1;
+	hit.position = ray.origin + ray.direction * t0;
 	hit.normal = normalize(hit.position - obj.position);
-	
-	return (h >= 0.0 && t > 0.0);
+	hit.normal *= (isInside ? -1.0 : 1.0);
+
+	return (discriminant >= 0.0) && (t0 > 0.0);
 }
 
 bool intersectPlane(Ray ray, GPUObject obj, out hitInfo hit)
diff --git a/shaders/light.glsl b/shaders/light.glsl
index 6b5d1ed..1bf4147 100644
--- a/shaders/light.glsl
+++ b/shaders/light.glsl
@@ -90,11 +90,9 @@ vec3 sampleLights(vec3 position, inout uint rng_state)
 
 vec2 getSphereUV(vec3 surfacePoint)
 {
-    // Convert 3D point to spherical coordinates
     float phi = atan(surfacePoint.z, surfacePoint.x);
     float theta = acos(surfacePoint.y);
     
-    // Map to [0, 1] UV space
     float u = (phi + M_PI) / (2.0 * M_PI);
     float v = theta / M_PI;
     
@@ -113,11 +111,9 @@ vec2 getTextureColor(hitInfo hit)
     else if (hit.obj_type == 3)
     {
         GPUTriangle tri = triangles[hit.obj_index];
-
         uv = hit.u * tri.texture_vertex2 + hit.v * tri.texture_vertex3 + (1 - (hit.u + hit.v)) * tri.texture_vertex1;
-        uv = vec2(uv.x, 1 - uv.y);
     }
-    return (uv);
+    return (vec2(uv.x, 1 - uv.y));
 }
 
 void    calculateLightColor(GPUMaterial mat, hitInfo hit, inout vec3 color, inout vec3 light, inout uint rng_state)
@@ -136,8 +132,8 @@ void    calculateLightColor(GPUMaterial mat, hitInfo hit, inout vec3 color, inou
     }
     else
     {
-        light += mat.emission * mat.color;
         color *= mat.color;
+        light += mat.emission * mat.color;
     }
     // light += sampleLights(hit.position, rng_state);
 }
\ No newline at end of file
diff --git a/skymap.hdr b/skymap.hdr
new file mode 100644
index 0000000..32c2f91
Binary files /dev/null and b/skymap.hdr differ
diff --git a/srcs/class/ObjParser.cpp b/srcs/class/ObjParser.cpp
index 5debd8c..04b3bf7 100644
--- a/srcs/class/ObjParser.cpp
+++ b/srcs/class/ObjParser.cpp
@@ -333,11 +333,13 @@ void	ObjParser::parseMtl(std::stringstream &input_line, Scene &scene)
 				throw std::runtime_error("OBJ: syntax error while getting material texture");
 
 			mat->emission_texture_index = scene.getEmissionTextures().size();
-			std::cout << "path " << mat->emission_texture_index << " : " << getFilePath(_filename) + path << std::endl;
 			scene.addEmissionTexture(getFilePath(_filename) + path);
+			
+			if (mat->emission == 0)
+				mat->emission = 1;
 		}
-		else
-			std::cerr << "unsupported material setting : " << identifier << std::endl;
+		// else
+			// std::cerr << "unsupported material setting : " << identifier << std::endl;
 	}
 	if(mat)
 	{