There is a possibility that one of the parts within your model, has colocated vertices.

A colocated vertex occurs when three vertices of the exact same polygon are lined up almost straight on with each other. This can cause a bit of confusion for makemdl as it has to figure out how to render such vertices.

As you know, a polygon consists of at least 3 vertices and 3 edges. If those three corners are lined up [making a smashed polygon], rendering the polygon may be impossible.

Another cause:

Many vertices of the same object-in-question might be in the exact same location [basically, vertices are clumped together].

Steps to help avoid colocated vertices:

1. Avoid using semi-spheres. Sometimes they can cause the problem. But if you're gonna use them, such as for making a nose cone of a prop, make sure that the vertices on the flat area are moved out of alignment.

2. Second, avoid the spline technique. This technique may be helpful with dealing curves, but it can cause the errors that you have in the same manner due to the complex nature of the spline tool. Besides, there are other [safer] methods for dealing with curves such as Box-modeling and Poly-modeling.

3. Select an object [any object that is basically complex] and highlight all the vertices. In the Modifier panel, scroll down to where it says "Weld". Click "Selected" and this will cause any vertex that is clumped together to be combined into one single vertex. This resembles the "Collapse" method, but the "Weld" method targets vertices thar too close to each other without needlessly affecting the rest of the vertices.

4. This following method is slow, but it will help you identify faulty objects within your model very early. After adding a complex object to a model, give it a special name and export it with the rest of the model. During the export [if you have middleman and mdlcommander installed], check the "keep error log" box before continueing. That way, if an error occurs, simply read the saved log and check to see if the object you made is responsible for the issue. Typically, the log will give you the name of the object by simply repeating it and tell you what it found. Deal with the object in Gmax, and export it again to see if it's been fixed. If it works, move on to the next new object you make.

This should help.

I find it interesting - unless my eyes are seeing wrong, that you have two poloygon/triangles co-located.  Note that the vertex x,y,z definitions for the two triangles are the same.

In this case, a simple welding of points *should* eliminate the problem.

Quote:


Felix is right, I've had this problem before and all you need to do is select all vertics on the shape and weld with default setting. That should solve you problem.