gmax polygon question

[Guest]

The tower screenshot explains the problem. The tower inside was also created so that one would see the interior. However one sees through the polygon to the ground. If you enter into the tower (pass beyond the glass then there is no problem) all polygons are as they meant to be.This happened only to the tower, although I have other transparent areas but no problems?Could someone please ????Letats

[Guest]

What texture format you have used for the transparent bitmap? If DXT change it to 8-bit format and it should be ok.

[arno 1]

I am afraid that changing the texture will not help.The problem is the drawing order. This must be so that the inside is drawn before the outside. Otherwise the z-buffeting of FS will remove it (as it would bleed through).I have had some succes by not checking the "optimize" checkbox in the exporter. But it will depend on the order of the objects if it works.This is, in my opinion, one of the bad parts of GMax. You can not control the drawing order and therefore it is very hard to get transparant objects to work correct (PS. This is also true for FSDS and most other design programs).Arno

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[Guest]

The texture is 8 bit with the glass colour made transparent in BMP2000.The order of constructing the polygons in gmax were, first the balcony and the upstandsthen the ceilinglater the corner posts to the glass surroundfinally the glass polygons.I have other transparent areas but they do not have a problem.????Can anything be done to overcome this?Thanks for your replies

[arno 1]

Maybe not optimizing helps, as optimizing mixes the parts of the objects and desturbes the drawing order. Otherwise I wouldn't know a solution, except from hand editing the source.Arno

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Member Netherlands 2000 Scenery Team[a href=http://home.wanadoo.nl/arno.gerretsen]http://home.wanadoo.nl/arno.gerretsen/banner.jpg[/a]

[Guest]

Are you sure this isn't just a normals problem?3D objects as a rule only have normals facing "one-way": that is, their faces can only be seen from one side. If you create a 3D box, for example, and then go "inside" it will disappear, at least unless you either flip the normals or create a two-sided material (that effectively creates normals on both sides.In this case it looks to me like we're just "seeing" the normals of the tower from the wrong side. In Max (regular old Max, the one I'm used to) we'd solve this problem by putting a two-sided material on the tower. Conversely, I suppose you could also create a tower "inside" where the normals are reversed.If gMax (and the usage of the model in FS) is different in this regard than Max I'm sorry if I created confusion here. I can't actually try this out until tonight, but I'd be glad to make sure of this in case anyone already isn't.

[arno 1]

From letats first message I quote:"If you enter into the tower (pass beyond the glass then there is no problem) all polygons are as they meant to be."So I assume it is not a normals problem.The problem described is a well know problem when working with transparant textures (especially when combined with more complex objects).Arno

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Member Netherlands 2000 Scenery Team[a href=http://home.wanadoo.nl/arno.gerretsen]http://home.wanadoo.nl/arno.gerretsen/banner.jpg[/a]

[Guest]

I had a similar problem.No logical explanation, but I used two texture bmps and the prob was gone (initially I had one bmp with textures for more than one objects). Only happens with transparent objects.George

[arno 1]

I think this can be explained by the following. If you use another texture there will be two material, while there was one before. During the optimilization of the object the polygons with the same materials are "collected" and this mains that you can get another drawing order with two materials and that can solve the problem.Arno

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