Only compile normals and light shaders when needed

src/main.cc

@@ -273,12 +273,17 @@ int main() {
   Mesh screen = {screen_vertices, screen_indices, {}};
 
   Shader main_shader       {"shaders/vert.glsl",        "shaders/frag.glsl"};
-  Shader normal_vis_shader {"shaders/normal_vert.glsl", "shaders/normal_frag.glsl", "shaders/normal_geo.glsl"};
-  Shader light_shader      {"shaders/vert.glsl",        "shaders/light_frag.glsl"};
   Shader skybox_shader     {"shaders/sb_vert.glsl",     "shaders/sb_frag.glsl"};
   Shader reflective_shader {"shaders/vert.glsl",        "shaders/reflective_frag.glsl"};
   Shader refractive_shader {"shaders/vert.glsl",        "shaders/refractive_frag.glsl"};
   Shader post_processing   {"shaders/pp_vert.glsl",     "shaders/pp_frag.glsl"};
+#if NORMALS
+  Shader normal_vis_shader {"shaders/normal_vert.glsl", "shaders/normal_frag.glsl", "shaders/normal_geo.glsl"};
+#endif
+
+#if POINT_LIGHTS
+  Shader light_shader      {"shaders/vert.glsl",        "shaders/light_frag.glsl"};
+#endif
 
   const float camera_speed  = 25.0f;
   glm::vec3 camera_position = glm::vec3(-2.5f, 0.0f, 8.0f);
@@ -377,12 +382,18 @@ int main() {
 
   // Set the shaders binding points
   main_shader.set_uniform_block_binding_point      ("Common", ubo_binding_point);
-  normal_vis_shader.set_uniform_block_binding_point("Common", ubo_binding_point);
-  light_shader.set_uniform_block_binding_point     ("Common", ubo_binding_point);
   skybox_shader.set_uniform_block_binding_point    ("Common", ubo_binding_point);
   reflective_shader.set_uniform_block_binding_point("Common", ubo_binding_point);
   refractive_shader.set_uniform_block_binding_point("Common", ubo_binding_point);
 
+#if NORMALS
+  normal_vis_shader.set_uniform_block_binding_point("Common", ubo_binding_point);
+#endif
+
+#if POINT_LIGHTS
+  light_shader.set_uniform_block_binding_point     ("Common", ubo_binding_point);
+#endif
+
   // Add projection matrix to uniform buffer
   glBufferSubData(GL_UNIFORM_BUFFER, 0, sizeof(glm::mat4), glm::value_ptr(projection));
   glBindBuffer(GL_UNIFORM_BUFFER, 0);