Straighten the vertices

Emanmaker · 11th January 2021, 06:50 PM

I'll explain it in another way: I'm building models for the model train simulator, "Rule the Rail!" The software requires the model to be inverted to align it in the environment. So before I invert the project, my model is straight and narrow like this....

However when I invert the model in while in AC3D, the vertices on each end of the model distort and "web" out like this....

I did try surface>flatten and no effect is there something else, or would someone take a look at what I'm missing or not hitting....?

Andy · 12th January 2021, 07:20 AM

I'm not sure what you mean by "inverting" but if you are getting black parts of the surfaces, it could be that the normals are being calculated wrong. This is usually caused by a concave polygon starting with the wrong orientation. You may have vertices overlapping (in the same place) within a polygon. Try running Object->Optimize vertices.

Try triangulating the problem surfaces. Or you could use Surface->change-vertex-order to try and remove the black parts.

Also, check all the normals are facing outwards (press 'n'). A quick way to test this is to set the surfaces to 1-sided and if anything is not visible from the outside, those surfaces need flipping.

11th January 2021, 06:50 PM	#1
Emanmaker Junior Member Member Join Date: Jan 2021 Posts: 11	Re: Straighten the vertices I'll explain it in another way: I'm building models for the model train simulator, "Rule the Rail!" The software requires the model to be inverted to align it in the environment. So before I invert the project, my model is straight and narrow like this.... However when I invert the model in while in AC3D, the vertices on each end of the model distort and "web" out like this.... I did try surface>flatten and no effect is there something else, or would someone take a look at what I'm missing or not hitting....? Last edited by Emanmaker; 11th January 2021 at 07:19 PM.

12th January 2021, 07:20 AM	#2
Andy Administrator Professional user Join Date: Jun 2003 Posts: 4,565	Re: Straighten the vertices I'm not sure what you mean by "inverting" but if you are getting black parts of the surfaces, it could be that the normals are being calculated wrong. This is usually caused by a concave polygon starting with the wrong orientation. You may have vertices overlapping (in the same place) within a polygon. Try running Object->Optimize vertices. Try triangulating the problem surfaces. Or you could use Surface->change-vertex-order to try and remove the black parts. Also, check all the normals are facing outwards (press 'n'). A quick way to test this is to set the surfaces to 1-sided and if anything is not visible from the outside, those surfaces need flipping.