Niko's Tutorial 1. Chrome and Shiny Metal Surfaces

I have decided to post this tutorial because I noticed a number of questions on the Blender discussion board about creating realistic looking chrome and/or shiny metal textures. I have spent many hours looking for an easy method for creating the reflective metal effect, and I think I have finally figured it out. There is no easy way. However, it is very possible. Here is a brief overview of the technique. Note: there may still be better ways to do this as well as many possible improvements on this method. I encourage you to notify me if you have any suggestions, but as always, be nice! (see email at bottom of page).

1. Introduction.

There is no "chrome" or "metal" texture buttons in Blender. There is a good reason for this, however. As with so many things in this world, a short-cut solution is almost always inferior to hard work and some ingenuity. The reflectivity that you see on metal or chrome objects in the real world are a function of the environments in which they are placed. If you put a chrome sphere in a completely black room, the ball will appear black. So when you want to see chrome on a car bumper, the chrome will only really look natural if it's based on an environment map. However, shiny metal surfaces are often not perfectly reflective, and sometimes the surfaces also have underlying colour(s) associated with them that are independent of the environment.

Underlying colours -grey, red and blue.

The key to this method of making the chrome or shiny metal effect is threefold:

a) make an 'environment' for your model. This can be as simple as two walls and a floor (with textures), or a bunch of different simple models scattered all over the place. It is important to have some colour and texture variety in the environment, so ensure that you don't simply rely on a single sky texture.

b) Environment map in texture channel 1 for your model. Tweak the settings to suit your needs.

c) Colour texture in texture channel 2 for your model. I use the colourband to select a colour, then I use the alpha value to set the degree to which the colour affects the overall appearance.

2. Make the environment.

Here's the layout for this scene. The walls are simply cloud textures (Noise size=0.682, NoiseDepth=5, white texture RGB, blue material RGB). The floor is some texture I ripped off of some texture page on the web. You can use pretty well anything you want. Just make sure it varies somewhat from the colour and look of the walls. I also put some red trim along the bottom of the wall. Don't spend too much time on this (unless the environment is part of your final product of course).

3. Environment Map.

A picture is worth a thousand words...

This is a simple environment map. The environment map copies 'snapshots' of the regions surrounding the model and 'pastes' the snapshots on the surface. Play around with some of the settings to customise the look. Note that the environment map is in the first channel. In the environment map settings, ensure that you type in the name of the object that is to receive the reflection effect (in this case, 'CurveCircle'). The foci of the snapshot is the object's 'centre' (wherever the pink ball is).

4. Colour Texture.

In the second texture channel, I start with 'marble'. Then I click on the colourband button and then delete one of the two colours, leaving a single colour. I reduce the alpha value and change the colour values to get a look that I like. In this case, the underlying colour of the metal surface is blue.

4. Result.

And here's a final product. To get rid of the background, just render the model, make the environment map 'static' (the default in blender) and then delete the environment.

5. Conclusions.

I think the chrome effect works fairly well. It's easy enough to remove the gold-ish appearance by making the colour channel grey instead of yellow, or using a different set of environment colours. Someone suggested altering the unified rendering settings to increase the shineyness of the final product (good suggestion, and can work well!). Other settings worth playing with include: the colours of the environment textures, emit values, the brightness of textures on the surface, and the amount of light in the scene. Generally speaking, the brighter the environment, the shinier the object appears. Now go forth my Blender brothers and sisters and make all your models of metal shine!

Comments or suggestions should be sent to niko@geopublic.com
Insults should be sent to Bill.Gates@microsoft.com