I forgot to add these.

Data/Shaders/GLSL/Shell.frag

@@ -0,0 +1,3 @@
+void main() {
+	gl_FragColor = vec4(0.25, 0.125, 0.125, 1.0);
+}

Data/Shaders/GLSL/Shell.vert

@@ -0,0 +1,7 @@
+void main() {
+	vec4 position = gl_Vertex + vec4(gl_Normal, 1.0) * 0.125;
+	// prevent skewing
+	position.w = 1.0;
+	
+	gl_Position = gl_ModelViewProjectionMatrix * position;
+}