Having forgotten what little French I ever knew, I used the Google Translator to get the following:
"I have a smoothed spline basis which gives a rugby ball shaped open-ended and wanting to close with " busy area " I found that the area has 3d rendering of the surface stuck with sketch based spline section , the surface is faceted ...
Is a subtle rendering engine ?
As to close I can only select the last spline profile and I have no option fusion and I have a surface that fits perfectly with the spline and no longer sticks to the smooth surface and is independent the smoothed surface.
If I hide it surface profile I then activated the option of merging and smoothing surface is selectable to have a surface that mouth perfectly smooth surface, but this surface obtained wife facets of the surface smoothed Evil
I tried doing a simple extruded spline surface and there is obvious: the surface section is produced facet and not perfectly matches the spline as it perfectly with climbing on a circle or polygon extruded ... .
Thank you in advance: wink:"
I am not sure I understand, but it sounds like you made a smooth shape like a Rugby ball, but with the ends open and you are trying to close the shape. You are worried that the open ends look faceted and wonder if that could be a problem with the rendering. Yes, there are limits to how well SolidWorks renders the shapes and you will often see faceted edges where the real geometry is smooth. Under Tools/Options/Document Properties/Image Quality, try pushing the slider on "Wireframe and high quality HLR/HLV resolution" all the way to the right to the "High (slower)" end.
You might try a Loft or Boundary Surface to a Point or a Fill Surface to close the end. You might want to add some Guide Curves with the Loft or Boundary or Constraint Curves with the Fill Surface. Use the Edge of the open surface, not the splines, as the starting edges of your closing surface.