Problem with flickering fabric

[realh]

I'm trying to create a mod with some textures copied from existing mods and some new ones I've created myself. The ones I've created are for StadiumFabric* and StadiumFabricStructure* with the FabricStructure files being copies of the corresponding Fabric files. I also found StadiumFabricL in other mods, it looked the same in both so I copied it to mine, but I didn't find a StadiumFabricStructureL. The trouble is the textures are flickering. It isn't just the usual z-fighting caused by bad mixing, even unmixed blocks are flickering. I think it's related to the depth sorting bug you get with some old mods with transparent textures, but I don't know how to fix it.

My textures had some transparency originally; I made versions with no transparency but that didn't entirely cure the problem. Most of the blocks have stopped flickering, but where I can look up at a roof (8-8-1) inside other fabric blocks the roof flickers, appearing to show through to the other fabric through it. I'm not sure whether this only happens when the second visible block is FabricStructure or if it also happens with Fabric, but like I said I just copied aech Fabric file to the corresponding FabricStructure.

I don't have Photoshop so I used GIMP. The textures are 1024x512 pixels. For the S I copied the N, brightened it only slightly and made it 50% transparent, because it isn't supposed to be shiny. For the N I used Gimp's Normalmap filter then decomposed into separate R, G, B and A layers and cut the red layer and pasted it into the alpha, then set the red to all black before recomposing. I saved them all with the BC3 DXT5 option and mipmap generation enabled.

My files are at http://www.realh.co.uk/tm/dds/.

A friend tried loading them into Photoshop and re-exporting them, but that made no difference. That was with an earlier version of the texture with broken normal maps (I hadn't moved the red to alpha), but I don't think that's the cause of the problem anyway. I also saw similar flickering when I tried using the fabric textures from Inca mod before making my own textures.

[popgun]

Hi realh,

Grab the modifies files here;
http://www.cadify.co.uk/signs/realh/realhStadiumFabric.zip
and add them to your zip.

I don't use Gimp so I can't tell you where you went wrong.

If you can 'aquire' photoshop, I can send you my actions files that make creating speculars and normals simple.

Otherwise finish your mod's diffuse files, send me a link and I'll make them for you, but you'll have to email me as I don't log in very often.

pop

[realh]

Hi, nice to hear from you.

Thanks for doing that, but it still flickers. I've made a fully opaque version but even with that the FabricStructure textures seem to keep switching alpha on and off, but luckily it's hardly noticeable in the track, so I can live with it.

The problem could be something to do with one of the other mysterious dds files, or lack of, or just a bug that doesn't usually get noticed because most tracks don't have so much fabric. plext and charn are close to finishing their Steampunk track and I noticed the transparent side of the fabric in that doing the same thing.

[realh]

I found a way to fix it at last. Just making StadiumFabricStructureD.dds fully opaque isn't enough, I also had to save it with BC1 DXT1 compression instead of BC3 DXT5. So it looks like StadiumFabricStructureD.dds just can't be transparent and you have to make sure TM knows it isn't by using a suitable format. StadiumFabricD.dds can be transparent though, so I've still got a reasonable level of transparency in that section of my track.

BTW, I don't think your actions are creating the right sort of normal maps for TM1. I noticed they appeared fully opaque, but I read you're supposed to move or copy the red channel to the alpha for TM. I remade my own normal maps that way and they do seem to look better.