Brazil Rio comes with an assortment of fun-filled new materials and shaders. In this tutorial, I will go over each one and try to give a few tips for general usage. Let's start with the dedicated purpose materials:

Skip Ahead:

Brazil Glass
Brazil Toon
Brazil Advanced (carpaint)
Brazil Advanced (skin/wax)
Brazil Advanced (others)
Brazil Utiliy and Brazil Basic

Brazil Chrome:

The Brazil Chrome material is a shader dedicated to reflection-only surfaces. You'll note that there is no slot for a diffuse map, as the chrome material has no diffuse component. This means that the chrome will not be affected by lighting (except for a specular highlight). The most important thing to remember with chrome is:

The appearance of the object, with the chrome material applied, relies entirely on the environment surrounding the object.

This means that if you have a teapot floating in space, and you render it with the chrome material on it, you'll just get a black frame, as the teapot has nothing to reflect, and therefore reflects the background color of black. So let;s experiment with the chrome shader:

1) Create yourself a teapot, torus knot, or any other curvy object you like.

2) In the material editor, make a new material and select Brazil Chrome from the list. Leave the material settings at default for now and apply this material to your teapot/object. 3) In the render dialog, activate the CSG ground plane in the CSG server rollout

4) In the luma server, turn on the skylight and set it's color to white (the little blue color swatch is the skylight color).

5) Set image sampling to min 0, max 2 and give it a render:

You should get something like the image above, with the white ground plane and black background reflected. Now let's get a little more interesting of an environment, before we start playing with the chrome.

6) Create a large cylinder above the teapot. Make it big and flat, and position it centered above the teapot, but high enough as to not be visible in the rendering.

7) Next, create another new material, although make this one just a standard material. Set the material's diffuse color to white and set self-illumination to 100. Apply this material to the new cylinder. Now give your teapot a render again.

Now we are getting some better reflections, but we should add one more level of complexity, just to make it a little less contrasty.

8) Open the environment panel (under the rendering menu) and poke the big button for the environment map.

9) From the list choose 'gradient ramp'

10) Drag an instance of this new gradient ramp into the material editor (be sure it is an instance and not a copy).

11) Now we need to change a few things. First, set the mapping type to 'Environ' and choose 'spherical environment' from the drop down menu. Next Enter a W value of -90, to rotate the map 90 degrees, aligning it to our environment. Next set the gradient to something like what I have.

After you've got these thing set, give your teapot another render and see how things have changed.

12) Okay, finally, let's add a spotlight and adjust our skylight a bit. Create a spotlight, so that it lights our teapot from the side, turn on it's shadows and set it's multiplier to .5. Set the skylight multiplier to .6. This should give us some directional lighting, which will be handy for testing later shaders as well.

Okay, now we have a good environment for testing this chrome (and for testing all the rest of our Brazil materials), so let's move on to the chrome settings. The chrome material is really pretty basic as far as settings go. There are the standard 2-sided and faceted checkboxes. There is a rollout for highlight parameters. The important controls here are those for filtering reflection, enabling glossy reflection and for enabling refelction decay.

First, let's set the filter color to red.

Now give it a render and see how it has changed.

This filter color swatch acts as a tint filter for your reflections. You can also stck a map in there for more control. The 'Env' color swatch and map slot below the filter color acts as a local override for the environment map (where we put the gradient ramp earlier), allowing you to customize environmental reflections on a per-material basis.

Set the filter color back to white and enable glossy reflections. This enables blurry reflections on the chrome, giving it an aluminum or brushed steel look.

Leave the rest of the settings at default values and give it a render.

The glossiness spinner (set to 80 by default) controls blurry the reflections are. 100 is no blur and 1 is maximum blur. The focus map slot lets you put assign a map to the glossiness. For example, you could put a checker map in there, and the black areas would be blurry and white would be not-blurry.

The sample rate spinner controls the number of samples, which basically breaks down to controling the quality of the blurriness. Lower sample rates will give you grainier reflections and higher sample rates will give you smoother reflections. Of course, higher sample rates will give you slower renders as well.

The Adaptive Sampling setting also has an influence over general quality. In this case, the max error spinner controls the amount of error allowed in the adaptive sampling. Higher settings allow for more error in the sampling, ie lower sampling rates, and faster renders. And, as expected, lower settings allow for less error, and give a cleaner solution, and slower renders. Basically this setting tells Brazil that if pixel A and pixel B are different by this (max error amount) much or more, sample some more.

Now, it sounds like the two controls pretty much do the same thing, but think of it like this: With adaptive sampling turned OFF, the sample rate is the rate which is used for every image sample. So if every pixel requires 4 image samples (say your image samples are set at 1/1) and your glossy reflection sample rate is at 15, you will end up with 60 samples (4x15) per pixel, for every pixel, no change. With adaptive sampling enabled, the sample rate effectively becomes a MAXIMUM rate. So in aforementioned case, instead of every pixel requiring 60 samples, some may require 22, some 47, and some the full 60, depending on the error threshold. So, in many cases, this will speed up glossy reflections ALOT, depending on what you are reflecting.

The next area, the reflection decay controls, act as a sort of reflection attenuation.

When activated, this puts a distance limit on reflections, preventing things outside of the End distance from being reflected, and instead reflecting a color or environment map (depending on the Fade To settings). This limit is not a sudden cut-off, but rather a fading from 100% to 0% reflection. Much like a lights attenuation, the start and end distances control where the fading starts and ends, and the Type drop-down menu controls how that fading occurs.

Reflection Decay Types (teapots reflected on the side of a cube):

That pretty much wraps up the chrome shader. Now, on to the Glass shader:

>>>> One down, six to go!! >>>>

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