>>I do too have this problem. I can get a double sides surface with AC3D
>>modeller using the "2S" button, but I don't get any double sided .ac
>>exported face with Blender. AC3D is time limited so, I don't have much
>>time to find out how to do the same with Blender. Any hint?
>
> This is because the author of the ac3d-export script made a conscious
> decision not to export 2 sided Blender surfaces as 2 sided .ac surfaces.
> The reason is that all the surfaces in Blender are 2 sided by default
> and this would result in either a lot of work for modelers or something
> close to a doubling of the polygon count for a model.
Well, I have to add that I import a lot of Wavefront .obj models into
Blender, they have one sided faces only, they are not autoconverted to
two-sided faces into Blender. Doing this, every object has one-sided
faces and Blender does the .ac exporting job very well. Why the hell
should I not have the opportunity to make just a few of those faces
double-sided and export them into a .ac file as they are? Sorry, but I
don't think that decision was _conscious_ as you say.
> The solution for modelers is to simply duplicate the surface that you
> want to be two sided and then flip normals. Personally, I almost never
> do this since zero thickness surfaces just don't occur in real life. I
> also use shrink/fatten on one of the surfaces to give the object some
> thickness.
Sorry Josh, I disagree with the above method; duplicating faces in order
to get double sided rendering into FGFS is not a solution to me at all.
That just increases the geometry and has bad consequences on
performance. I would not suggest this solution to anybody.
By the way, FGFS does not resemble reality with high fidelity at all;
ok, it aims to that, but we are far from that. In the meanwhile, we
accept a lot of compromise between reality, performance and visual
quality into FGFS. Most 3d objects have to be seen from a distance and
do not need high poly geometry at all; zero thickness surfaces are very
often used and are a very good solution for building lowpoly objects
with double sided visible geometry.
> Nope, I tried and he convinced me of his viewpoint. Sadly, the default
> behavior in Blender is not configurable without recompiling.
That is something Blender developers should face one day or another.
Blender is going to grow every day more, it has to cope with a wide
variety of modellers' needs; it has to be flexible with respect to that,
otherwise it will stop being used, even if it's free.
I know modellers have so much variable needs considering the peculiar
field they are involved, the different techniques each and everyone
develops in order to adapt the software tools to their own needs _and_
vice versa. A modern 3d modelling software can't afford being stuck to
default settings like that one :-(
I really don't know Blender very deeply, but those news make me think I
should not spend a lot of my time on it.
Roberto
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