Rendering with mental ray: Final Gather and Global Illumination

Autodesk 3ds Max Tutorials > Lighting and Rendering >

The following tutorial is designed to make you a mental ray wizard for interior architecture in two, two-hour sessions. Enjoy the trip.

The scene used for the tutorial, shown below, incorporates an interior room with daylight/sunlight. All materials use the new mental ray Arch & Design material that's part of mental ray 3.5 and is included in 3ds Max.

Scene in viewport

Next we show the scene rendered, without any global illumination. It is quite dark, as sun hits only a part of the scene. This is ideal for testing global illumination algorithms, as the dark parts will get all their light indirectly.

Scene rendered

TipTo achieve optimal performance, we recommend that you use the mental ray Arch & Design material wherever possible. This material uses sophisticated importance-sampling techniques that can produce substantial overall speedup. A performance factor of up to 10 times is possible for final gather, especially glossy floors as well as materials with weak reflections. Improvement can be even greater with more bounces.

In this tutorial, you will learn how to:

Use final gather (often referred to by its acronym, FG), including multibounce to obtain more realistic scene illumination.
Accelerate scene rendering time by combining final gather and ambient occlusion.
Use photons to effectively distribute light energy in a scene.
Combine final gather and photons for optimal performance.

Skill level: Intermediate to Advanced

Time to complete: 3 to 4 hours

Files for This Tutorial

All the files necessary to do this tutorial can be found on the program disc. Before doing the tutorials, copy the \tutorials\mental_ray directory from the disc to your local program installation.

Lessons in This Tutorial

Final Gather

Final Gather and Ambient Occlusion

Photons

Photons and Final Gather

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