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WIP CN SD40-2W DLC Reskin Projects

Posted:
Mon Nov 21, 2011 11:00 am
by roinuj
Hi All,
I've started my next reskin project. I'm trying my hand at a protypical weathering re-skin for the
DLC of the CN Wide Nose SD40-2.
Here is a link to the reference photos.
CN 5284 on RailPictures.netHere is what I've done so far. I still have more work to do plus I'm not 100% satisfied with the weathering effect and will continue to work on this but your comments and suggestions will be much appreciated. Like my GATX re-skin, I hope to put together a reskin package for the RWA Library in the future.


I did run into some problems with the panel lines on the long hood. It seems to me this model has the doors modeled in 3D and it creates the dark panel lines regardless of the texture. I tried a couple of things but couldn't over come the problem.
Thanks, Don
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Mon Nov 21, 2011 1:41 pm
by imnew
Don, you tha man ! Looks amazing as it is

Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Mon Nov 21, 2011 2:38 pm
by BNSF650
Looking good once again.
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Mon Nov 21, 2011 6:25 pm
by Kali
If you need any little panels for higher-resolution lettering and so on made up, I'm quite willing to do that. I don't think you've mentioned if you've any experience with 3d work, so sorry if it's stepping on toes :)
Anyway I'm glad you started that, because I pulled mine out the other day and it looked ... in need of attention, let's say.
I wonder if you'd be happier with the weathering if the bumpmap worked better ( if it's even got a bumpmap ).
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Mon Nov 21, 2011 9:14 pm
by roinuj
Thanks everyone for the encouraging words. I'm glad I'm on the right track.
@Kali
My 3D skills are limited to real world buildings (I'm a design/build contractor by day) but when it comes to Railworks 3d, scripting, shaders etc. etc. I'm afraid its all Greek to me.
As for the bump maps, the only is a generic one. Nothing for the panels. I'm not 100% sure but it looks to me the panels are modeled in 3d and it renders with unattractive and inconsistent black lines.
I would definitely appreciate any help or guidance you have with regards to improving the project.
Thanks, Don
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Mon Nov 21, 2011 9:33 pm
by Kali
Well, bumpmap ( normal map really ) are easy, you just have to think of them as height data - you don't paint shadows as such, you let the normal map generator do that. First off you need the plugin from nVidia ( which is in the same place you get the dds exporter I think ).
The normal map is mapped the same as the texture it's attached to, thankfully - which is helpful as you can use the texture as a guide then. If we take the side of the SD40 as an example, as you look at the texture imagine the engine is on it's side for the explanation:
* Let's call the body itself the reference height
* Doors are a bit ( quite a lot ) higher than the reference
* Any rust pitting is a bit below the reference
So, when you come to make the source for the normal map:
* Body reference height is 50% grey, so just fill it with that
* Doors are significantly above, so I would probably make white rectangles using the door edges as the rectangle edges
* Rust pitting is a bit below, so just fill the centres of the pits with some sort of mid-dark grey.
* Rivets/protruding panel lines - do the centres in some shade of grey-white
* You can add some sort of gentle pattern fill either side of 50% grey to add some panel warping also
Flatten the image, and run the nVidia normal map plugin: you'll end up with a bright blue layer with the same colour rectangles surrounded by lines of varying shades of red/blue/green. Insert that into the normal map texture & see how it looks, and then just experiment. Technically it works by changing the angle light bounces off parts of the model, the stronger the colour difference from the reference blue, the bigger the angle. You might find you have to use the option to reverse Y values, iirc.
If the doors are in 3d I don't know how much use that will be, but I guess it's worth playing.
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Mon Nov 21, 2011 11:32 pm
by roinuj
Kali wrote: Insert that into the normal map texture & see how it looks, and then just experiment. Technically it works by changing the angle light bounces off parts of the model, the stronger the colour difference from the reference blue, the bigger the angle. You might find you have to use the option to reverse Y values, iirc.
If the doors are in 3d I don't know how much use that will be, but I guess it's worth playing.
@Kali

For the suggestions.
I read up on creating the bump map and think I'm okay there but where I'm confused is on how to deploy into the game. Do you include as a layer in the base texture image and then save as a .dss and convert or do you save it as a separate file and reference it in a blueprint? If the latter, were in the blue print do you make the changes/additions?
Thanks
Don
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Tue Nov 22, 2011 12:32 am
by Kali
It's a seperate map in the material used to build the model, so it's a seperate texture file and it already exists; you convert it just like any other texture file ( and once you've built one you can copy/paste/use it as a layer just like any other texture also ).The ones for this model seem to be called SD_40_Wide_bump_nm(c), so that's uncompressed ( _nm ) and compressed ( _nmc ) ones. I'm at the wrong PC to actually open any texture files so I have no idea what SD_40_alpha_nm is - I think I might have to take a look at the shape for this model because it might do something a bit wierd. Most of the old models have bumpmaps that don't really do much, I've never looked at the ones for this model though.
Wierd how I complained for ages about models being too bright, and now I'm complaining default models look too dark! guess it's just the new lighting.
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Tue Nov 22, 2011 10:23 am
by roinuj
@Kali,
Thanks for the clarification. So if you don't have original 3d model, there is no way to add a bump map unless one was created by the original content creator?
When I started I looked the bump maps for this asset.
SD_40_Wide_bump_nm(c) is just a generic material texture.
SD_40_Alpha_nm(c) is fan, window glass and some text details.
I initially tried some "bumps" using this technique I found.
http://www.michaeldashow.com/tips_bumpmaps.html but when added to the model, it didn't seem to work. I noticed some weird things like strange highlights on the louvers that makes me think they are modeled as well.
I created a blank tetxure to try see the under modelling details. Looks very well detailed. I'm not sure what is happening on the louvres.

Regards
Don
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Tue Nov 22, 2011 10:28 am
by roinuj
I decided to take CN5284 for a spin on the Bay of Quinte route last night.

Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Tue Nov 22, 2011 11:12 am
by Kali
Looks well at home there :)
That's not how to do RW-type normal maps, however:
http://www.game-artist.net/forums/spotl ... pping.html is what you're after ( just the bit on adding to the generated map - the rest of it is a rather nice tutorial on generating them from Max )
Edit:
http://jarrodchristman.com/normal.php is a better one.
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Tue Nov 22, 2011 12:54 pm
by roinuj
Thanks for the reference Kali, I'll bookmark have a good look at them. Looks very informative. I really need to learn more about modelling for RW and get my head around this.
I knew the method I tired was not the true method to do it but thought it may be a faux way of creating texture when there seems to be no useful bumpmap for the panels. Without one, I don't know if there is anything else I can do to improve how the repaint will look, especially the panel lines in the area of the zebra stripping.
Thanks for all you advise.
Don
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Tue Nov 22, 2011 1:07 pm
by Kali
If panels aren't defined enough I tend to use a vector mask of the edges with a neutral fill layer ( usually 50% grey and overlay so I can maybe add a layer mask with some noise later if I need it ), and generally just use layer effects to bring out the edge shading a bit. That doesn't help with reflections being a bit flat which is where the normal map helps, but conveniently you've just made a fill layer of all the panels :)
If there are better ways of using PS I'd be happy to know, because I'm entirely of the "well that seems to work" school of training.
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Tue Nov 22, 2011 1:17 pm
by PapaXpress
Kali wrote:If panels aren't defined enough I tend to use a vector mask of the edges with a neutral fill layer ( usually 50% grey and overlay so I can maybe add a layer mask with some noise later if I need it ), and generally just use layer effects to bring out the edge shading a bit. That doesn't help with reflections being a bit flat which is where the normal map helps, but conveniently you've just made a fill layer of all the panels :)
If there are better ways of using PS I'd be happy to know, because I'm entirely of the "well that seems to work" school of training.
I would like to know more about how to do this. From previous post (long ago) I asked about vector mapping, but you said this was something that could be done in Illustrator, not CS3. Are these two different things? How would I create this mask in CS3?
Re: WIP CN SD40-2W DLC Reskin Project

Posted:
Tue Nov 22, 2011 1:35 pm
by Kali
I think I probably meant it was better done in Illustrator,not that you couldn't do it :) Illustrator is most definitely less annoying for vector work; PS has no alignment tools other than snap, for one thing ( unless they're really well buried ).
For fill layers as described above:
* Create new fill layer of 50% grey, set it to overlay.
* Layer -> Vector mask -> hide all
* Select your new vector mask
*- To draw a random shape, select the pen tool and start making points in the mask. I posted a howto about making curved shapes in GIMP with bezier curves a while back in response to a post of Mike's, it's the same concept.
*- If you just want a rectangle or a circle or some other predefined shape, use the shape tool.
There are a lot of options for shapes - not least the options whether an individual shape adds/subtracts/intersects with the overall contents of the mask. The manipulating of points on lines is best left for a tutorial from the web somewhere rather than me trying to condense it here.
You will now have a totally invisible shape layer! lovely. Open the blending options for the layer, and for the sake of this example, enable Outer Glow. Go to the options for Outer Glow, set the colour to black, blend mode to Multiply, opacity to 50%, size to... lets say 8, Range in the Quality section to 70% and antialiased. If you now click away from your new fill layer so the outline of the shape disappears, you'll find a basic shadow as if your shape was a raised area. Bevel might be a better idea for outlining side panels themselves, but the general technique is the important idea ( and bevel does slightly different things - outer glow isn't bad for getting a little dirt round the panels quickly ).