diff --git a/f_shader.glsl b/f_shader.glsl
index a26bf41..dd010e0 100644
--- a/f_shader.glsl
+++ b/f_shader.glsl
@@ -2,7 +2,7 @@
 uniform vec4 ambient, diffuse, specular;
 uniform float shininess;
 
-varying vec3 eye_pos_i;
+varying vec3 pos_i;
 varying vec3 normal_i;
 
 void main(void)
@@ -11,7 +11,7 @@ void main(void)
     vec4 color;
     float NdotL, RdotEye;
 
-    lightDir = vec3(-0.1, 0, -0.9);
+    lightDir = normalize(vec3(-0.1, 0, -0.9));
     color = ambient;  /* ambient light */
     n = normalize(normal_i);
 
@@ -22,10 +22,10 @@ void main(void)
         /* diffuse component */
         color += diffuse * NdotL;
         /* specular component */
-        RdotEye = dot(normalize(eye_pos_i), normalize(reflect(-lightDir, n)));
+        RdotEye = dot(normalize(-pos_i), normalize(reflect(-lightDir, n)));
         if (RdotEye > 0.0)
         {
-            color += specular * pow(RdotEye, shininess);
+            color += clamp(specular * pow(RdotEye, shininess), 0.0, 1.0);
         }
     }
 
diff --git a/v_shader.glsl b/v_shader.glsl
index efb7e85..6fde1ce 100644
--- a/v_shader.glsl
+++ b/v_shader.glsl
@@ -2,12 +2,12 @@
 attribute vec3 pos;
 attribute vec3 normal;
 
-varying vec3 eye_pos_i;
+varying vec3 pos_i;
 varying vec3 normal_i;
 
 void main(void)
 {
     gl_Position = gl_ModelViewProjectionMatrix * vec4(pos, 1);
-    eye_pos_i = vec3(gl_Position.x, gl_Position.y, gl_Position.z);
+    pos_i = vec3(gl_Position.x, gl_Position.y, gl_Position.z);
     normal_i = gl_NormalMatrix * normal;
 }