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akriesman

Seam Problem. Fixed, but expected solution !

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Ok, I solved the seam display/flashing problem. The problem had to do with the textures, but it is still very strange and unexpected. And, it is not directly related to the texture mapping. If you look at the two textures below. Texture A is the texture that gave me the seams. Texture B corrects the problem.Now, I know the first thing in looking at the textures, is that you might think that I had incorrectly mapped the right side of the textures into the black area. But, this is not the case. The black areas occupy colummns 252 thru 256 (256x256 bitmap). My texture mappings for the far right side of the model were 0.9804 (X-axis). As I reduced this number, the visible texture portion began to shift to the left, which was several pixel positions fromthe black portion. Yet, the black seam was still shown.When I changed to the texture from A to B (below), the problem went away. Even though the black portion is not in the mapped texture area, it still affects the edge of the displayed polygons somehow (causing the flashing).Texture A:http://ftp.avsim.com/dcforum/User_files/3dfb7d6372d12e7e.jpgTexture B:http://ftp.avsim.com/dcforum/User_files/3dfb7d8273c5cef8.jpgIf anybody has any comments on this, I would like to hear them. Or, if I need to explain the problem/solution more, I can try. This problem should affect all the scenery design packages GMAX, FSDS, and others. It is not really a problem with the texture mappings, but seems to be a problem with the way the texture mapping is applied when the polygons are displayed (DirectX, or the translation from BGL to DirectX primitives).By the way, this is an opaque texture. I tried several types 565, DXT1, etc.What do you think ?Allen

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Guest Cazador

Dear Allen:Yes i have the same porblem using FSDS 2 and gmax, see my post (14/12/02) with the topic FSDS 2 texture Problems.Thanks.Alfredo Mendiola LoyolaLima Peru

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Hi Allen I have never got that problem what are tool are you using ?FSDS or gmax and what version(of gmax at least?) I still use version1.1 as I had problems with 1.2 crashing when I worked on meshes done with version 1.1. Second do you get the above with "simple" bitmaps(I.E. no mipmapped textures)? I am thinking it might be related to"texel" display maybe?. Second what did you do to texture "B"?. Dan

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I have never had the problem myself, but I think it can have to do with the mipmaps. For the lower resolution version of the bitmap the black line can shift a bit of course (because the bitmap is smaller). Maybe that is the solution?Arno


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

Arno

If the world should blow itself up, the last audible voice would be that of an expert saying it can't be done.

FSDeveloper.com | Former Microsoft FS MVP | Blog

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That's what I am thinking but I still would like to know what Allendid to the second texture. Dan

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Dan,All I did on the second texture was to minimize the contrasting portions.If the boundaries in my mapped texture area are lighter, then I make sure the area just outside of the mapped area is lighter (or the same color/texture).I did this with all my textures and the problems have gone away. Very strange.Allen

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After reading the reply, I wanted to clarify. In the above examples, there are different colored steel wall textures. The black areas to the right are not mapped, so I had left them black. All I did in the second texture example (:( was extend the colors out to fill in the black area.Hope that makes senses.Allen

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Arno,I originally thought the problem was related to the MIPMAPS, so I removed them all. I still see the seam even when getting right up to the building.Allen

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Humm, interesting, then I wonder where the problem comes from...Arno


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

Arno

If the world should blow itself up, the last audible voice would be that of an expert saying it can't be done.

FSDeveloper.com | Former Microsoft FS MVP | Blog

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Guest PaulL01

>Ok, I solved the seam display/flashing problem. The problem >had to do with the textures, but it is still very strange >and unexpected. And, it is not directly related to the >texture mapping. >>If you look at the two textures below. Texture A is the >texture that gave me the seams. Texture B corrects the >problem. >>Now, I know the first thing in looking at the textures, is >that you might think that I had incorrectly mapped the right >side of the textures into the black area. But, this is not >the case. The black areas occupy colummns 252 thru 256 >(256x256 bitmap). My texture mappings for the far right >side of the model were 0.9804 (X-axis). As I reduced this >number, the visible texture portion began to shift to the >left, which was several pixel positions from >the black portion. Yet, the black seam was still shown. >>When I changed to the texture from A to B (below), the >problem went away. Even though the black portion is not in >the mapped texture area, it still affects the edge of the >displayed polygons somehow (causing the flashing). >>Texture A: >http://ftp.avsim.com/dcforum/User_files/3dfb7d6372d12e7e.jpg >>Texture B: >http://ftp.avsim.com/dcforum/User_files/3dfb7d8273c5cef8.jpg >>If anybody has any comments on this, I would like to hear >them. Or, if I need to explain the problem/solution more, I >can try. This problem should affect all the scenery design >packages GMAX, FSDS, and others. It is not really a >problem with the texture mappings, but seems to be a problem >with the way the texture mapping is applied when the >polygons are displayed (DirectX, or the translation from BGL >to DirectX primitives). >>By the way, this is an opaque texture. I tried several >types 565, DXT1, etc. >>What do you think ? >>Allen This is caused by mipmaping... regardless of your removing the mips, via bmp.formats etc. FS will still mipmap a non mip texture the only way around this is to use an alph an the old 444DXT format and for what ever reason FS2k2 will not mip those (if it is not the 444 I can look it up to be sure) But that,s not the answer to your problem, and as I see it it is no problem at all as you seem to have figured it out by extending the the used image colors to the edges thus no dithered black edges etc. Just to be clear >It< (using the black edge in your bmp) is the problem even if you dont use a miped format as FS2k2 will still mip taking up a bit more cpu/gpu power to do so more than a pre-miped bmp.

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