Tuesday, 3 December 2013

Fiat 126

1.      Research

 Vehicles are not something I'm confident with. I would say I prefer more organic shapes. This is why I decided to partially drop the concept of a shiny hard surface of modern vehicles and literally go towards the organic. And since I'm not a big fan of vehicles I created something I'm most familiar with. A car, that is.
I wanted to make a small vintage car and give it a rusty look. Since the project was really about the shaders, I wanted to make the surface partially reflective by blocking it out in reflective map. The first vehicle that came to my mind was Fiat 126p. It was produced in Poland as a slightly different version of Italian Fiat 126. We call it Maluch (Little One) and until recently I've known it only by this name.  The type of car I was ashamed to get inside as a teenager, because it was considered not cool and you had that feeling as if it's going to fall apart while driving. I wanted to build it in 3D for some time now. As people get older they start to appreciate those embarrassing moments from their past.

There, there, in all its glory. It is quite cheap and works great as a canvas for mechanics.

Or art students.

 It can be transformed into a tank.

A train.

 A flying machine.

A... carriage.


From all of these Google gave me one inspiring image, which I chose for my final idea.

It's a painting by Zdzisław Beksiński. Another great artist from my own country that I didn't know about.
I liked the idea of the veins/webs growing on the vehicle like this. I practiced Zbrush over the summer and it seemed like a great opportunity to sculpt it nicely and quickly. Of course the veins would have a rather matte surface which left me with only a few bits of untouched hard reflective surface.

2.      Modelling and texturing

I didn't really waste much time and got straight to building a base mesh. I got blue prints from the internet and got it going.

Obviously my aim was to make it really organic but in the end it was still a car which was once new, shiny and expensive looking. I had to keep some hard edges. That's why I decided to make two normal maps - one from a high poly using a Turbo Smooth in 3Ds Max, and the other would be my sculpt from Zbrush - then combine them together in Photoshop.

While making a high poly in 3Ds Max was a matter of 15 minutes, sculpting the veins on the top of the surface was very time consuming. I really wanted to stick to the painting as much as I could.

It took me roughly one day to produce a finished sculpture. Although the veins on my reference are much broader I thought to save more untouched space for flat reflection. Also it is less work.

Now that I had both of my high poly meshes ready I thought of using Zremesher to create a completely new low poly model. It would be faster and require but a press of a button. I’ve used this plugin over the summer and although it didn’t do a very good job with retopologizing a human figure, I reckoned it will do better with a regular object. In the end my vehicle was not a complicated one.

I had to put guidelines to specify edge flow.

Unfortunately it didn’t work out quite well. It completely changed the shape of my mesh. I wish for a day when retopologizing would be absolutely automatic. Instead of being lazy I just worked on my base mesh. After all there were just few mistakes requiring attention. After that I was more than ready to bake everything down.

Thanks to this process I started to notice differences in baking programs. In most cases Xnormal seems to be doing a well better job. Even though you can adjust the cage of your bake in 3Ds Max, Xnormal maps are clearer and more detailed. Although there are spots I needed to paint over in Photoshop. Having two normal maps for my disposition gave off better results I suppose. I could cut out bits and pieces from each one and combine them nicely together.

One of the reasons I decided to sculpt a vehicle in Zbrush was less seams on my normal map. Why wouldn’t I do the same with diffuse? I experimented with colours and textures and had it straight on my mesh. Then I just baked the entire thing out again. I got a basic diffuse, normal map, ambient occlusion and cavity map.

I've always been a fan of using hundreds of layers just in case. Although even if it was all named properly and each group had a different colour I still cursed myself for creating so many.

I really don't know why on earth I have never used masks in Photoshop before. Currently I could put a mask on every single layer; this is how great they are. It not only helps you blend things more nicely but also allows you to recover your entire image. It's like magic, only better.
The entire process of texturing was rather long and boring. I kept jumping between PS and 3Ds Max every 3 minutes to see how the changes look on the actual mesh.

It seemed like I had the main body pretty much done. It was time to make the rest.

I’ve been told of this fantastic way of making tires in 3Ds Max. It’s basically dividing a plane into smaller parts, bevelling them up and chamfering the edges. Next you copy it next to each other and weld it together. Then you put Bend modifier and fiddle with the settings so the whole thing wraps up together. It makes me think of the infinite ways of making everything in 3Ds Max if you only have the brains. Which I don’t.
Voila! A wheel fully baked and textured. Only things left to make were side mirrors and some nice but very basic interior. I decided I’m not going to have glass windows at all. If the veins are sneaking inside the vehicle I would have to either have them shattered – bits and pieces sticking out. I really liked the idea to be honest but I also knew I’m running out of texture space and main body is the priority. Also my colleagues kept complaining about alpha channel not working properly with Codemasters shaders.

Here I have my fully modelled and textured Fiat with standard shaders. It’s time to change the graphics mode and make everything shiny and not necessarily beautiful.

3. Shaders

Alright, I missed those shadows in realistic viewport. First thing I needed was blocking out my reflection so it only affects the left side of my mesh. I thought I would use Zbrush again.

Again, I did not get seams and  I had a better understanding of where the reflection should be blocked.

That was pretty much done. I painted the rest in Photoshop.
I love working on little details. I think it’s both an advantage and a disadvantage. I usually need someone to tell me it’s enough.
Looking back at my reference I still needed to put the same kind of veiny surface underneath the vehicle. Since the shaders will not cope with alpha channel I’ll just have to use a standard shader.

Fortunately it took me less time now. I baked it to a regular plane and take those textures into Photoshop to improve diffuse and paint a simple alpha channel.

It turned out the alpha channel decided it will not work, not even as a standard material. I was tired of trying to fit this in. There aren’t even this many settings you can fiddle with and no matter what shader I used it simply will not work. I kept getting strange fringes. The texture keeps flickering on and off when I moved the mesh around. I had to drop that idea. 

I always enjoyed making a skybox. I used my own photographs and blended them together with images from Google.
I planned on making my environment very simple and since it was an open space I had to build an entire sky dome.

Maybe when the lighting is baked it will start looking better.
Cube map is next.

Apart from that all I really needed to do is resolve the small issues around everywhere. For example, side mirrors had unwanted noise on their normal map which obviously affected the reflection.

4. Conclusion
In the end I was pleased with the outcome but expected better from myself. I only know I worked really hard on. Sadly I also know it doesn’t matter when the results are poor.

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