Brazil Features

Raytracing

Brazil's render engine uses the raytracing method (as opposed to scanline or hardware renderers). Raytracing has the advantage of simulating the way photons actually behave; although raytracing is not limited to realistic solutions.



Brazil's advanced raytrace engine simulates a wide range of effects including:

• Reflection
• Refraction (transparency)
• Dispersion (prismatic rainbow effects)
• Sub-surface scattering (diffuse light
• transmitting materials such as wax or skin)
• Glossy Reflections (blurry or brushed
• materials)

Advanced Lighting

Rhino supports point, spot, directional, linear and rectangular light objects with simple properties such as colour, hotspot, and shadow casting.
Brazil adds about 100 more light properties.
The number of light properties can be intimidating, but most of these settings are
only needed in a few specific cases.

Brazil light features include:

• Decay (darkening of light as a function of
• distance to the source)
• Attenuation (amplification of brightness as a
• function of distance to the source)
• Focus control (rectangular, conical,
• cylindrical etc.)
• Projections (emitting a picture or procedural
• texture instead of a colour)
• Exclusion lists (lights ignore specified objects
• in the scene)

Brazil will also display focal cones and attenuation spheres for selected lights in the viewport, so you can see the affects of your settings in real-time.

Cartoon and NPR

Brazil includes non-photoreal (NPR) effects such as toon shaders.

(Car)Toon shaders cooperate with photoreal shaders so you can mix glass, brushed metal and toon in a single scene without losing the ability to do indirect-illumination, depth-of-field or any other effect.



You can specify the behaviour of fills and inks including:

• Multi-level paint fills (discrete colours applied
• based on luminosity)
• Gooch type fills (continuous gradient)

Depth of Field

Depth-of-field (DOF) simulates the imperfect focusing properties of physical lens-systems such as biological eyes and cameras. DOF adds a measure of realism to a rendering by blurring out-of-focus areas. It can also be used to "mask" areas of the scene such as distant surroundings.



The settings for DOF include:

• Focus Distance
• Radius
• F-Stop
• Bokeh Aberrations (the appearance of
• out-of-focus areas in an image produced by
• a camera lens using a shallow depth of field

Procedural Textures

Brazil supports both bitmap and procedural textures. Bitmap textures use images (a grid of coloured pixels). Procedural textures, on the other hand, are defined by a mathematical function. Procedural textures do not suffer from resolution or tiling problems, and it is easy to change their behaviour. Procedural textures are simulated in the Rhino viewport to make adjustments easy.



Brazil built-in functions:

• Checker
• Dots
• Gradient
• Marble
• Noise
• Tile
• Wrinkled

Advanced definitions can be used to create other realistic materials such as wood and stone.

High Dynamic Range Colours

Brazil is a High Dynamic Range (HDR) engine. With an HDR rendering engine, colours are not limited to the black~white range. Colours can be brighter than white and darker than black. "Brighter-than-white" colours are important even though the computer screen cannot display them, because colours in a rendering are often diluted by partial reflection or refraction.

Global Illumination

Global Illumination is a feature you will find in most modern rendering platforms including Brazil. Global Illumination uses both direct and indirect illumination to generate a realistic image. Direct illumination is the process where light objects cast light onto objects creating bright areas on surfaces that face the light source, darker areas on surfaces that do not face the light source, and shadows when surfaces cannot "see" the light source directly due to some obstruction. After a surface has been lit directly, it emits photons and some of those photons are captured by other surfaces and some of those photons are finally caught by our eyes or a camera. The effect of indirect illumination is relatively small compared to that of direct illumination. Yet, it is very important to the "realistic" quality of the image.