Our first goal with interactive render (IR) was the full integration our OpenGL viewport. This way, IR can be used the same way with the same navigation controls. Besides the integration with the viewport, full integration with the rest of UI is implemented, so that almost every function of Thea works in co-operation with IR. This way, we can tweak settings, apply materials, etc. with IR keep working in the background.

The second goal, was the render method itself. We wanted a new mode that would be as fast as possible especially in initial updates. Although this can be parameterized to use TR1/TR2 unbiased methods, for IR we developed two "lighter" techniques; one progressive biased and a Monte Carlo unbiased.

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