Polygon Normals help 3D Software determine which side of a polygon is the front vs. back face. This is extremely important to understand as objects with “flipped” normals will oftentimes not render properly. At times you’ll have an entire model with flipped normals or at times just a few polygons. We’ll discuss normal direction as well as how to reverse the normal direction on geometry that’s reacting oddly. In practice, normals should always be facing outward from your model. This will allow the software and renderer to read them properly. Normals play a huge role in the shading, lighting, and rendering by allowing you to further manipulate a flat surface with detail as seen in bump or normal maps. We’ll discuss these maps in detail as we get to materials and rendering in octane.