Using replacement parts

…We've used Insert Meshes before, in order to…add shapes to the surface of other objects.…But there's another way that it can be used.…ZBrush has a feature called Replacement Parts.…And it's used to literally patch a…model seamlessly onto the surface of another model.…Let's see how it works.…So what I want to do in this video is…add a little, sort of sensor nodule onto the helmet.…So let's Alt click on it to…make it the active subtool.…Now the way that replacement parts work is you have to define what…part of your mesh you want to be replaced by the new model.…

So we do this with polygroups.…Let's hit Shift+F really quick so we can see…that there's no polygroups on this model right now.…I'm going to hit shift+F again, just to make it easier to see, and now…let's mask off an area that we want to be defined by a new polygroup.…Now, this replacement mesh…that I want to make is kind of oval shaped, so let's just paint in an…oval mask here, and then we can convert…this mask to a polygroup by hitting Ctrl+W.…So the mask goes away.…