subject: 3D Patch Modeling Procedures [print this page] Author: Daniel Kreimer Author: Daniel Kreimer
Patches can be used to model mostly smooth surfaces. Although the technology can do edges very easily, that type of modeling is best suited for a clean and proper Polygonal model. Creating organic shapes is very easy. For the most part, you will need to think about building objects from a center point outward. Through patch propagation, you will simply add more and more patches as you build outward. Eventually, you will end up with a smooth, flowing surface with no seams. A feature that both patches and NURBS surfaces share is their capability to have relatively low detail models in the viewports and then render higher detail versions. This feature, called Surface Approximation, allows you to specify both the viewport and rendering quality of a model. This makes building and editing both patch and NURBS surfaces very easy-and detailed.Patch models have some limitations associated with them that can present problems if you are used to modeling a specific way. For instance, if you like to build an object using defining shapes such as a Loft object, you will be unable to accomplish this. Patches can be built from primitives, or Patch grids, and that is it. You can, however, convert a Polygonal object to a Patch surface by applying the EditPatch modifier. Doing this turns your Polygonal mesh into one big patch with a ton of vertices. For the most part, this is impractical except for on the simplest of Polygonal meshes. Perhaps the most popular modeling technology to come around has been NURBS (Non-Uniform Rational B-Spline) modeling. Simply put, NURBS modeling excels at smooth surfaces but can also do sharp edges very well. It seems as if everyone is using NURBS to build their 3D models-from characters to cars. Like patches, NURBS allow you to create complex detail that is rendered but not necessarily displayed in the viewports. This means that both the construction and editing of NURBS surfaces is fairly straightforward.About the Author:
