Quad Versus Tri Patches in 3D Modeling

Although it is possible to turn any type of geometry into a Patch surface using Edit Patch, this technique is highly inadvisable. Doing so creates an enormous amount of Control points that will either be extremely difficult to edit or may crash your 3D Application entirely. The best way to build patches is either from Patch surfaces or via the your 3D Application primitives.

If you decide to use Patch surfaces as your foundation for patches, you have two choices: Quad or three-sided Patch. Both types of patches create the same geometry initially. The visual difference is that you can see the Tri Patch is made up of triangles, whereas the Quad Patch is made up of four-sided shapes. The main geometric difference between using either one is what happens when you add to an existing patch.

When you add a Quad Patch, you are adding another square-like patch. When you add a Tri Patch, you are adding a three-sided Patch object-that is, a patch that comes to a point. When you are custom patches no minimum adding massive sections to an overall object, you should probably use Quad Patches. When you are adding in a patch to cover a small area for detail, you should use a Tri Patch. You can add either type of patch to existing Quad and Tri Patches.

This means that if you prefer to use Quad Patches most of the time, you can always add a three-sided Patch where you need it. Quad Patches are best for large sections of geometry. When you are building the cheeks of a face or the forehead, you can usually get away with Quad Patches. As a matter of fact, it is better to start with Quad Patches and add three-sided Patch where you need them.

This is primarily due to what happens when you use a patch as a flat surface. Quad Patches have less geometric detail information to bend with and produce more faces in order to bend properly. Therefore, if your surface requires little curvature, stick with Quad Patches. They will work better when it comes to editing.