I am fairly new to blender, I started using it about a month and a half ago, have a few models done, but haven’t textured anything. In my most recent model I encountered a odd phenomenon where after exporting the model as a fbx and importing it into my game, a bunch of surfaces were not rendered. However you can view these surfaces if you go inside the model. My question is, what is this called, and how do you define which side of a face is rendered?
Looking back at the model in blender, the parts are two slightly different colors.