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[karla]

I've almost completed CVA-31 but I am perturbed by uneven shading, or differences in lighting, on the carrier flight deck. It can be seen in reply #67 of https://www.sas1946.com/main/index.php/topic,42027.50.html. The stern third of the deck is obviously darker than the rest of the flight deck. One can also see other differences in shading around the ship which are certainly not caused by differences in the texture maps. The uneven shading is always at the boundaries or edges of the various objects in the 3D model.

Is it because of my graphics card or what?

Ubuntu 14.04 64 bit/ Wine 1.7.34
IL2 1946 4.12.2m with High Resolution/True Color Textures Mod by carsmaster and SA~Storebror
NVIDIA GT240

[Gumpy]

I don't know about the graphics card or 3D model part of it karla but,uneven shading or the stern third of the deck being obviously darker would be a good thing I think.Planes landing causing tire marks on top of that planes staging there before flight ops leaking hydraulic fluid+oil and tons of foot traffic would obviously make the stern darker.           Tons of uneven shading.

[karla]

Thanks for the reply Gumpy.

I don't think you appreciate the level of detail in my model, there are 15 layers of texture in Gimp to create just the map for the flight deck surface - tyres and oil being two of them.

My problem is the rendering in game due to the graphics card setting, the HD mod, interference between sub-models or something else. Because I know the texture maps are as good as I can make them I will have to release CVA-31 as it is.

[Stainless]

Check your normals are facing the right direction.

I have seen this many times on HIM files, even stock ones.

If not check the material properties in game, especially the ambient and diffuse settings.

[karla]

Thanks Stainless. I've been working on the model for 7 months now and still spot the odd normal that's in the wrong direction. It's easy to see in Blender 2.49b - the face becomes transparent. So, the problem with the huge flight deck areas is not because of normals. The materials in question are shared across a number of faces and objects and vary in their rendering in game; the Blender 3D model looks perfect. Puzzling. However, I can just about accept these variations and guess that not many others will bother much and I will therefore release the model as is - but I'll carry out a post mortem and study my archives to see when the problem first arose.

Thanks anyway.

[just champi]

Hi, karla,
Have you checked smoothing groups? I haven't used Blendy exporter (nor Blender since a loooong time) but with Buggy it used to export everything with just one smoothing group so the shading around the whole object once exported in game looks odd.
May it be that the Blendy exporter has some issues with smoothing groups, I doubt it, but just in case...

My bet is that maybe you need to make use of "null" material to make the separated parts of deck (or hull if it's the case) look smooth once exported. I'm not familiar with shipbuilding at all, but this odd shading looks like this kind of issue. There is a tutorial by Loku
https://www.sas1946.com/main/index.php/topic,2707.0.html
explaining how to setup null material and what to do next. Basically you need to have attached to the main hull parts some extra faces that will be deleted after export the mesh object. This will keep the smoothing without breaking it along the borders of separated meshes that should look as one continuous surface.

[BOYAN]

There is something similar on Colossus class model too, but on hull... Is there an easy fix for it?

[just champi]

Hi, Boyan,
I can't tell if this is really the case, as I may be completely wrong, I really don't know what the modelling requeriments are for ships, it's just the impression I've got looking at the pictures.
Textures usually hide or mask smoothing or uneven shading issues, that's the reason I use a simple texture as a skin filled with just one medium-light colour to help me when checking these kind of issues.
If the lack of null material is the reason for the uneven shading, a bit of work is needed from the modeller to re-export the parts after adding some extra faces and fiddle a little deleting a bunch of geomtry and texture vertices in the .msh text files.

[karla]

Thanks for areas to start looking Stainless and just-champi. I can see the same problem on the Colossus, Boyan: one third from stern is a modelling joint and possibly a crooked one at the bow third. I was unable to discover when the problem first arose and, unfortunately, I haven't the time this month to carry out any tests.

I came across "non conformant texture clamping" which may be the culprit. Apparently, in older games seams at the edges of textures are visible in GL and Nvidia has a fix for it. However it didn't work with my setup. It may only be a problem with OpenGL (I should have said I'm using OpenGL) and not with DirectX, so, I'll leave it for now. If I find a fix for it I will post here.

Thanks anyway.

[Stainless]

Why don't you try loading it in my modtool and see what it looks like.

It's just a different renderer and although I can't say it matches the in game renderer, it map give you some clues.

[karla]

Thanks Stainless. I was unable to get your modtool to run under Linux/Wine at first attempt. I've tested out a few more suspect parameters including my NVidia settings.

I'm using carsmaster's and storebror's HD mod and used their "Lite" version with no effect. I've also varied settings in my CVA-31 .mat files with little or no effect - except specular and specularpow. They had a significant effect on the appearance but didn't eliminate it.

It looks like a rendering engine problem and I intend to test it out sometime soon (if possible, with Stainless' modtool or even in a locally built Windows environment (I'm running Ubuntu)).

Its a minor problem which will get solved someday ......

[Stainless]

One thing I have noticed on carrier decks is you can get issues with precision in the depth buffer.

I would try playing around with the "tfShouldSort" flag in the materials and see what happens.