Terminology
Also known as: Surface Patch, Bezier Patch, NURBS Surface (with bezier interpolation)
A patch is made up of 2 parts, the control points and the resulting tessellated mesh. The control points are the parts that the user interacts with in the editor. The tessellated mesh is a preview of the final polygons.
Patches are mainly used to build terrain in SSX. That includes the main track, hills and cliffs. They're also used for infrastructure such as roads, rooftops and tunnels.
That being said, you may find that patch editing is not that intuitive at first. If you want to give the best experience to the player you need to make sure to follow the best practices.
Recommended to learn:
- Bezier curve editing
This is Blender's built-in patch type. It allows free control over all points and extruding in both U and V.
Limitations:
-Notice how the edge of the left surface patch has a ramp? That is an incorrectly tessellated mesh. If exported it would look like the one on the right in game.
- No automatic alignment. You will have to select all the points surrounding the edge of a segment if you want smooth continuity.
For example. If you wanted to create a hill on figure A. You would have to select the 6 points between the segments (figure B). Then move them up (figure C).
This is a custom object type in BXTools. It allows free control over all points but it does not support extruding.
If you use this type make sure not to modify the topology. You can only change the geometry i.e moving vertices.
Overall this is a very limited patch type. If you know 3D modeling you may find some use in it.
TODO
As you can see from this image, Patch Objects can hold multiple Patch Segments. In this case there's 2 segments in 1 object.
Note that this image shows the "Spline Cage" patch type.