Doc:Tutorials/Materials/BSoD/part1e

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[edit] Bump

It’s very common for any surface to have bumps, either as the result of damage or by the natural makeup of the surface. Adding these details can help fool the eye into believing the render is real. Such details don’t have to be exact photographic duplicates of what you can see or what’s in the photograph. For instance the wood grain on the desktop would be very difficult to copy exactly. However, it should be possible to come up with similar pattern and color so that it looks like the simulated desk was produced from the same materials as the original. So lets have a go at creating the wood grain.

[edit] The wood surface grain

If you look closely at the grain within wood you will see that it has both depth and color. In other words they form dents in the surface of the wood. If a covering of varnish or stain has been added then quite often the grains fill slightly with the covering and darken. That’s exactly what has happened with the desktop in front of me. In fact the grain is quite pronounced and much darker than the wood surface. Fortunately we can use textures to simulate the wood grain.

[edit] Textures are our friends (wood)

Since we have 10 Texture slots available within any single material we have plenty of space to add a wood grain to our material.

It’s possible to add a new texture from within the materials button.

Select the Texture tab from within the Materials button.

LMB on the empty texture slot below the one we have already created.
LMB on the Add New button to create a new texture in that slot.

You will notice that the name of the texture appears to be identical to the last one called Tex. However, the actual texture name is Tex.001. You could change it here by LMB on the name and entering one of your choice. It’s easier to do that however, in the Texture button.

Press F6 (Texture Button)

The Texture button also has a Texture tab where you can Add New textures.

You can change the name of any texture that’s selected by clicking the name and entering one of your choice. Here I have changed the name of both textures as a reminder of their function.

If you can’t think of a name or you are completely lazy you can use the little motorcar icon. This will generate an automatic name based on the type of texture. Be warned however, that if you try to automatically name a blank texture its name will be None.

NOTE:

It’s always a good idea to meaningfully name things in Blender and Materials and Textures are no exception. You can easily lose track of what you are doing without the discipline of a good naming convention. Names are restricted to 19 characters which should be more than enough to help you out.

Back to our wood surface. Examination shows me that the grain is made from 2 elements. There are some broad elongated concentric rings that are slightly darker. Within those there are some thin and dark wood grain that has a pronounced indentation in the wood. We will start with the broader concentric rings.

I have chosen wood texture and RingNoise with a Noise Size of 0.250 and a Turbulence of 16.10.

Go back to Materials button F5 so that we can decide how it will be mapped to the material.

[edit] More Mapping

This texture is only being mapped to the Nor value.

This refers to the normal of a surface which when applied with different textures will produce simulated bumps in the material. They are not real bumps so they won’t alter mesh edges but they will give a very realistic interpretation of bumps & indentations on a surface. They will react with light shining on them and will appear as though they are self shadowing. Therefore deeper bumps will appear in shadow.

[edit] Stencil

Stencil will act as a mask on all texture slots that follow it. The Neg switch will reverse the stencil. These are great for restricting where a following texture will appear on our material. The reason it is being used here is because I want some small tight grain to only show through on some parts of the material. Thus leaving some of the original surface showing through.

[edit] Size

You will also see that I have changed the size of the texture to:-

sizeX = 0.300
sizeY = 3.00
sizeZ = 2.00

Those sizes were found after a few tests reaching a point I was happy with.

[edit] Previewing

It’s possible to preview a material without resorting to a full render. The material button now has a very capable preview tab that derives its picture using the same render engine.

Although small you get an impression of how the material might look when applied to a variety of surfaces.

There is also a very neat preview screen that you can now setup in any window by pressing SHIFTP.

You can resize the preview by dragging the bottom right corner of the frame. Again the render uses the same engine and therefore is a good method of previewing as you are working on materials.