Making Of 'Caterham'
I'm 23 years old and I have been into 3d since 2002, fascinated by my interest in 3d video games which was booming at that time. For the first few years I was just trying it out not to seriously and like most beginners in 3d I focused my time in learning modeling, maybe for to long, before I realized that texturing, lighting, and rendering skills was also important/ more important in creating good 3d scenes. Recently I got a job doing minor / light 3d work. Luckily the job gave me an opportunity to advance my 3d knowledge because I had free access to the web threw the office computer.
Before I started this scene I wanted to try to make a scene witch I could use all of what I have learned. I was also excited to try out Brazil which my friend had recommended for its quick and powerful materials, lighting and rendering system.
The idea for this scene came from a Caterham model that I saw at a hobby store a few weeks before. So the next time I went there I had to buy it. I was hoping to find a blueprint of the model car in the box but it wasn't there! So I had to build the model first and measure each object.
I then modeled the separated objects starting out using simple box and cylinders then turning it into an editable poly. Where I used the extrude, bevel, chamfer, cut, and slice tools to get the right topology. Finally I added a meshsmooth separately to each object of the car. I also used layers to manage the different parts of the car
For the tires I started out making it from a box, then deleted the bottom and frt/back faces that I didn't need. I used the cut tool to create the treads pattern, also trying to keep it clean. Then I extruded the selected polys and chamfered the edges to smoothen the edge (I did not want to add a meshmooth to the tire). I then copied it about 15 times and attached them all together. I then added a bend modifier to the tire objects making it into a cylinder.
Usually that would be it for the modeling part for me, but this time I wanted to make an environment for the caterham. I searched for any reference pics using google image search. And I found that most caterham images had the car in a country road environment. So that was what I wanted to make.
The "environment" scene included the road, grass (on the side of the road), and the wooden stake.
The road was just a 2x2 plane. I turned it to an editable poly, selected the front and back edges and used the connect tool to add several lines for making the elevated waves for the road.
The grass in the side of the road was divided into 2 layers. The closest was made by taking a few blades of grass which I mesh edited from the Society garlic foliage in max. Then I used the scatter tool to scatter the blades of grass on a small narrow plane. Add a planar uvw mapping modifier for texturing. And then instancing it along the edge of the road. I made dense and thin grass groups using this technique. I did edit random individual blades in editable mesh mode to randomize the appearance.
The second or back grass was made by several planes instances which I textured with a pre-render grass model I found on the web (I didn't want to merge the tall grass meshes into the environment scene because it would crash everything). I also adjusted the plane individually so it won't look the same.
Before I started texturing, I merged the car and wheel objects (which was made in different scenes) to the environment scene.
For the texturing some people prefer to setup the textures in Photoshop using layers. But I like to use the mix map in 3dmax to setup complex textures because it's easy to adjust each texture's size and coordinates individually. Even sometimes it might not be as efficient and add rendering times a little bit more, I still prefer this way of managing my textures. I used Brazil's advanced material for most of the texturing.
The road texture was the most complex because of the multiple mix maps I wanted to use in one material. I started by adding a mix map to the diffuse/color slot, for the main asphalt, then added layers of mix maps for the cracks, road lines, and dirt textures that made up the road. The crack texture which I found on the Internet was important because it added something extra so the road won't look so plain. I copied the diffuse map to the bump slot to add some bumps on the road. Finally I applied soft glossy reflections (using Brazil's glossy reflection control) masked with a mask map which made the reflection on the cracks a little bit more intense then on the asphalt, and none on the dirt.
The road diffuse mix map would probably take up one whole tutorial by itself, so here's the road's material navigator (only the diffuse slot), to keep it short.
For the grass mat, first I added an uvw planar map, and then in the material editor I applied a perpendicular/ parallel falloff map in the diffuse slot of the grass material (so the grass would have different shades of color depending its angle to the camera). The first map slot I added a mix map. In the mix map the first color I change to a dark yellow color and for the second slot I added a bitmap image of GRASS2.jpg. Then I added a gradient ramp map in the mix amount slot to simulate the transition from the green grass bitmap to the yellowish color.
For the plane grass objects I got the texture by pre-rendering the model of the tall grass in different side angles using the same lighting setup, and saved it as a TGA image file with separated alpha channel. Then I added the tga color image for the diffuse slot and added the alpha map image for the opacity slot of the plane grass material.
For the tire texture I wanted to get a clean tread grooves and a dirty groove. I needed to make a bitmap image which I could use as a mask map. The first thing I did was to turn off the bend modifier on the tire object and placed a new plane object underneath the treads, revealing only the extruded part. I gave the plane a matte shadow material so it would show only the black background and gave the tire a 100% self illuminated white material. Then I rendered it from the top view, making a blk & white map which could be used as a mask map later on
After I rendered the blk & white tire mask I added a planar uvw mapping modifier set to map channel 1 below the bend modifier in the modifier stack (for adjusting the blk white tire mask later).
I assigned a multi-sub-object material with 2 mat slots to the tire. When using multi-sub-object material I had to assign different material ID's to the treads(groove area)(1) and to the side of the tire poly(2). The first slot in the multi-sub-object material was for the treads area (area which made contact with the ground) and the second slot was for the side area (brand and specs of the tire).
For the treads material I used a mix map for the diffuse slot. In the mix map the first map slot I just used a dark grey color. The second map slot I added a noise map with the same color of the asphalt road. For the mix amount maps slot I added another mix map. In the new mix map I added the black & white tire mask image in the first slot. The second map slot was just the color black. And for the mix amount map I used a black & white noise map to add some randomize texture to the tire.
For the side of the tire I first added another planar uvw mapping modifier to the top of the modifier stack of the tire and change the map channel to 2.
The material for the side of the tire was just a diffuse dark grey material with a really low amount of reflection, and I also turned on the glossy reflection control (glossiness=25.0) to add soft blurred reflections. The brand and specs lettering was made by adding a black & white bitmap in the bump map slot and changing the bitmap's map channel to 2.
The materials for the car's paint were pretty basic. But before I added the materials for the car I added an HDRI image (I got on the web) to the environment map slot, instanced it to the material editor and turned it's coordinates to environ with spherical mapping, so the car's materials would have an environment/sky to reflect.
For the car's paint I used the technique of using a falloff map from green fading to a dark green/almost black for the diffuse, and a fresnel falloff of IOR 2.0 for the reflection.
One of the things that I liked about Brazil's advanced material was the glossy reflection control which controlled the softness/blur of the reflection, making reflections look more natural/ realistic. The metal material I used for the car's frame was made buy changing the color of the frame material to black, then adding a fresnel falloff of around IOR 10, to the reflection map slot. Then I turned on the glossy reflection control and adjusted its amount to 90. So it won't look like a perfect chrome material.
The lighting was very simple. I wanted to make a warm partly sunny look. First I turned on Brazil skylight in the rendering window, and set the color to a light blue color. Then I added a light yellowish orange omni Brazil light for the sun, I placed it in the front right top of the car. I did not use Indirect Illumination for this scene.
Rendering and Post Production
I used Brazil for rendering, texturing, and lighting the scene. The rendering took about 5 hours at 2500x1875 resolution, and saved it as a TGA image file with separate Alpha channel image which I used as a mask in Photoshop.
The final image, after I looked at it, I realized that it was not as bright as I would like. I could of re-rendered it again and increased the sky and omni amount, but instead I used the new shadow/highlight image adjustment in Photoshop cs to brighten the image, and it almost looks like faking indirect illumination/bounces.
I then adjusted the color, levels, saturation, contrast & brightness of the car image. The sky background was from Google image search, but it wasn't as large as the resolution rendering of the car, so I had to scale the image then apply a blur filter to decrease the noise. Then I rotated the sky image to follow the camera angle.
To make the grass look softer and denser I first used the blur tool in Photoshop and stroke the grass vertically with a big size brush to give it the dense and soft look. Then I duplicated the first Caterham layer and set the new layer's opacity amount to 50. For the first Caterham layer I added a light gaussian blur and for the second Caterham layer I used the sharpening filter(so the profile of the grass won't fade away). When I was finished with all of the adjustment I again used the blur tool to carefully fake DOF blurring in the image.
I wasn't really confident with the compositions of the final image and kept tweaking and trying different "styles" with it until now, that's why for the future I would like to learn more about composition of color, light, and space(does anybody know any references?). Also learn about the "artistic" side of creating a 3d image. But for now, overall, I'm pretty happy with the results of this project.
The Caterham project took me 2 weeks to finish. Half was for modeling and the other half was for texturing, lighting, rendering, and the post production.
For any questions please feel free to email me.