Now that 3.6 is out, it's time to show some of the new stuff we have been working on
The bread and butter of most Indigo users is arch-viz, and a lot of arch-viz consists of sunlight and glass. So we have two new features that should make for some massive improvements for such scenes.
The first is arch glass. Arch glass will be an option for specular materials. It uses some trickery to approximate the flow of light through thin glass. Although it is an approximation, it should be a highly accurate one, and should result in much faster rendering convergence.
Indigo arch glass correctly handles multiple reflections, as well as absorption in the glass. It's as easy to use as ticking a checkbox on the specular material settings.
The second new feature is a change to the way exit portals work - you will now be able to see through them, e.g. you can still use them in a window even if the outside of a room should be visible as well. You can even use them for exterior shots looking into a building.
In this test, we are looking into a room with glass on the window. The cactus is a reflection in the window.
Old: (50 samples / pixel)
This test uses an exit portal on the window.
As you can see, the outside is now visible. Also the reflection of the sunlight on the chrome sphere cleans up much faster.
Old:
) but it would be nice to have invisible objects not to be rendered in reflections too.. 
