Good, you should be way caught up to speed now. From now on I am going to assume you get how to do this.
With the material assigned and viewing the map we can make further changes to how the map is "mapped" onto the surface. The simplest, and sometimes most efficient - yet not always the best - way to make a quick adjustment is by changing the tiling right here in the Material editor.Â What I want you to do is this: change the Tiling under the Coordinates rollout to 3 on both the U and V coordinates. As you can see, we are now telling Max to repeat the base image along the surface 3 times, also known as tiling (Fig.27).
The problem with this method is that we have changed the whole material. This means that every object in our scene that gets this material assigned will have the image tiled 3 times.
If you want one object to have it tiled 3 times and another 20 times then you will have to apply a UVMapping modifier to the one you want tiled more and adjust the tiling in the modifier. This is actually a preferred way to do this because you really should handle Mapping coordinates on a per-object basis, but for now this method will work for our needs. Or you could make a duplicate of this material and change the tiling just on the copy and assign that to the other object but hopefully you can see the redundancy and the waste of time in that method.
Now we need to go back to our main material level.Â Do this by hitting the Go to Parent button (Fig.28).
Here, at the top level of the material, we will do what I tell my students is the absolute least you can do when making materials: copy the map in the diffuse channel to the Specular Level channel and the Bump channel. To do this just click and hold on the map in the diffuse channel and drag it to the Specular level channel, choose Copy when asked and then do the same to the Bump channel and again choose Copy (Fig.29).
As I said this is the least effort you can put into making you materials. Why? Because you have given Max enough information to simulate a basic material.
Let's take a look at the render now to examine. I'm going to zoom up to sphere so we can see the details a little better.
Let's compare (Fig.30 - 31).
See the difference? Diffuse with no specular or bump is just plain flat. This is what most of my students seem to do and they wonder why their renders are so flat.
By just copying channels we bring so much more realism to our objects, but like I said this is the least you should do.
Now, I didn't add a comparison render showing with diffuse and just specular because adding the bump doesn't change much at first. However, let's play with that now.
In the Maps rollout, go down to the Bump channel and raise the Amount to 120 (Fig.32).
Here is the render
Here the only thing we have done is increased the amount the Bump channel is effecting the whole material.Â But as you can see our sphere seems to have a little surface texture with 120 as compared to 30.
This is a lot better but the downside is that we are using the same image for all three channels.Â The Specular Level and Bump channel convert images into grayscale and thereby uses black and white to determine how much effect is seen.
This generally is not accurate. This is what we get (Fig.35 - Specular and Bump).
While at first this might not seem that bad, notice how there is basically no whites in the greyscale image.Â This means that nowhere on the surface will we find full effect.
What I want you to do now are save these images so we can experiment (Fig.36 - Save this as SlimyMetal_spec.jpg, and Fig.37 - Save this as SlimyMetal_bump.jpg).
Hopefully you can already see the major difference, so let's go ahead and use them. Back in the Material Editor, go into the Specular Level channel and load in the SlimyMetal_spec image. Do this by clicking on the Bitmap slot under the Bitmap Parameters rollout and then go and choose the correct image (Fig.38).