Parametric NURBS Modelling in Ayam

submited by
Style Pass
2021-06-21 19:00:05

This page describes some experiments with parametric NURBS modelling in Ayam while creating the Marsrakete image: 3D-Version Marsrakete   Toggle 3D!

Since the image is rendered using a simple cartoon/cel shader, everything (yes, every rivet!) has to be pure geometry, no textures will help. Luckily, in Ayam, you can do this easily with the help of the ExtrNC and Clone tool objects. But let us have a look at the overall scene structure first:

The main body is a surface of revolution that depends on a curve, currently selected in the upper image. To create a wing attached to this surface, three curves are extracted, and, together with other curves, skinned (the flow of geometric information is shown by red arrows in the above image). Since the curve extraction only extracts curves over the full extent of the surface, small Script objects trim the extracted curves to the right length. The wing is put into a Clone object to easily have any number of them. In addition, the advanced Gordon caps have an appearance (they close the non-planar wing surface as can be seen in the wing detail image):

Let us move on to the rivets, this time we are using the extracted curves as trajectory to place them on. Again, since the ExtrNC object only provides curves that extend over the full length of a surface, small Script objects trim the extracted curves to the right lengths.

Leave a Comment