diff --git a/src/context.c b/src/context.c
index 32b1f18..df0dc5c 100644
--- a/src/context.c
+++ b/src/context.c
@@ -4,8 +4,6 @@
 void set_clean_color_context( unsigned char r, unsigned char g, unsigned char b )
 {
 	glEnable( GL_DEPTH_TEST );
-	glEnable( GL_CULL_FACE );
-	glCullFace( GL_BACK );
 
 	glClearColor( (float)r/0xff, (float)g/0xff, (float)b/0xff, 1.0 );
 }
diff --git a/src/data/shaders.h b/src/data/shaders.h
index 5ae40ac..07eac94 100644
--- a/src/data/shaders.h
+++ b/src/data/shaders.h
@@ -25,7 +25,7 @@ const char * vs =
 	"	index=idx;"
 	"	vec3 aNormal = vec3(aNormal_x,aNormal_y,aNormal_z);"
 	"	vec3 aPos = vec3(aPos_x,aPos_y,aPos_z);"
-	"	Normal = mat3(transpose(inverse(rot*mdl))) * aNormal;"
+	"	Normal = normalize(mat3(transpose(inverse(rot*mdl))) * aNormal);"
 	"	gl_Position = fix * rot * mdl * vec4( aPos, 1.0 );\n"
 	"	FragPos = vec3( rot * mdl * vec4(aPos, 1.0));"
 	"}";
@@ -52,26 +52,26 @@ const char * fs =
     "uniform sampler2DArray palette;"
 
     "in float index;"
-    "out vec4 FragColor;"
     "in vec3 Normal;"
     "in vec3 FragPos;"
-    "uniform vec3 viewPos;\n"
-    "const float specularStrength = 0.5;\n"
+
+    "out vec4 FragColor;"
 
     "void main()"
     "{"
     "   vec4 color = texture(palette, vec3(0, 0, index));\n"
-    "   vec3 lightPos = vec3(0, 0, -15);\n"
-    "   vec3 lightDir = normalize(lightPos - FragPos);\n"
-
-    "   float diffuse = max(dot(Normal, lightDir), 0.0);\n"  
 
+    "   vec3 viewPos = vec3(0, 0, -15);\n"
     "   vec3 viewDir = normalize(viewPos - FragPos);\n"
+
+    "   vec3 lightPos = viewPos\n;"
+    "   vec3 lightDir = normalize(lightPos - FragPos);\n"
     "   vec3 reflectDir = reflect(-lightDir, Normal);\n"
-    "   float spec = pow(max(dot(viewDir, reflectDir), 0.0), 32);\n"
-    "   vec3 specular = specularStrength * spec * vec3(1.0); \n"  
 
-    "   vec3 result = (0.5 + 0.5 * diffuse) * color.rgb + specular;\n"  
 
+    "   float specular = pow(max(dot(viewDir, reflectDir),0.0), 16);\n"
+    "   float diffuse = max(dot(Normal, lightDir),0.0);\n"  
+
+    "   vec3 result = (0.5 + 0.5 * diffuse + specular) * color.rgb;\n" 
     "   FragColor = vec4(result, color.a);\n" 
-    "}";
\ No newline at end of file
+    "}";
diff --git a/src/mesh.c b/src/mesh.c
index 21861c1..1b0758b 100755
--- a/src/mesh.c
+++ b/src/mesh.c
@@ -32,8 +32,8 @@ mesh_t create_mesh( float * d, float * n, unsigned char * coordanate, unsigned c
 	glEnableVertexAttribArray(3);
 
 	glGenBuffers( 1, &p->n_vbo );
-	glBindBuffer( GL_ARRAY_BUFFER, p->n_vbo );
-	glBufferData( GL_ARRAY_BUFFER, p->vertex*m*sizeof(float), n+1, 
+	glBindBuffer( GL_ELEMENT_ARRAY_BUFFER, p->n_vbo );
+	glBufferData( GL_ELEMENT_ARRAY_BUFFER, p->vertex*m*sizeof(float), n+1, 
 		GL_STATIC_DRAW );
 	glVertexAttribPointer( 4,1,GL_FLOAT, 0, m*sizeof(float), (float*)(coordanate[0]*sizeof(float)) );
 	glEnableVertexAttribArray(4);
diff --git a/src/surface.c b/src/surface.c
index 40f67df..737a2ac 100644
--- a/src/surface.c
+++ b/src/surface.c
@@ -43,8 +43,9 @@ void klein(float *d_surface, int i, int j, int grid_size)
 float * generate_surface(int grid_size)
 {
 	unsigned char m = 4;
-	long size = grid_size*grid_size*2*9*m;
 	function_t f = klein;
+
+	long size = grid_size*grid_size*6*m;
 	float * d_surface;
 	int k=0;
 
@@ -55,14 +56,6 @@ float * generate_surface(int grid_size)
 	{ 
 		for (int j = 0; j < grid_size; j++)
 		{
-			// triangle 1, front
-			f(&d_surface[k + 1], i, j, grid_size);
-			k+=m;
-			f(&d_surface[k + 1], i + 1, j, grid_size);
-			k+=m;
-			f(&d_surface[k + 1], i + 1, j + 1, grid_size);
-			k+=m;
-
 			// triangle 1, back
 			f(&d_surface[k + 1], i + 1, j + 1, grid_size);
 			k+=m;
@@ -78,14 +71,6 @@ float * generate_surface(int grid_size)
 			k+=m;
 			f(&d_surface[k + 1], i + 1, j + 1, grid_size);
 			k+=m;
-
-			// triangle 2, back
-			f(&d_surface[k + 1], i + 1, j + 1, grid_size);
-			k+=m;
-			f(&d_surface[k + 1], i, j + 1, grid_size);
-			k+=m;
-			f(&d_surface[k + 1], i, j, grid_size);
-			k+=m;
 		}
 	}