[Bf-committers] Blender render architecture - Interleaved sampling

[Magnus Löfgren]

Hi,

Being a non-programmer and lacking understanding of blenders render
architecture, I'm not sure if this is a stupid question.
But how much work would it take to implement interleaved sampling in
blenders internal renderer for Motion Blur and Depth of field?
http://www.cs.ubc.ca/labs/imager/tr/2001/keller2001a/

Blender has raytraced area light shadows and glossy reflections after all,
and a similar approach must have been made in this area.

If this is indeed a mammoth task and there isn't enough time to implement
this, how about another approach to optimize the multi-sample motion blur
and multi-sample DOF already present in blender 2.4x?

For example to in Project Messiah, their internal renderer (it shares the
same roots as Arnold from Sony), when you render motion blur, the raytrace
samples are divided by the amount of passes, so that each "sub-frame"
rendered is extremely noisy, but merged together produces noise free
results.
It's still a multi-sample "render-the-whole-scene x amount of times" but
alot smarter than blenders approach, when you can keep the amount of samples
in each subframe to a minimum to reduce total rendertime without sacrificing
quality. So you can increase the amount of passes to reduce the common
strobing effects of multipass motion blur.

In blender, the noise pattern remains identical for each subframe, so
reducing the amount of samples in ambient occlusion or raytraced shadows to
take advantage of multi-pass rendering didn't really give an advantage like
in Project Messiah.

Of coarse interleaved sampling would still be ideal since strobing is
completely eliminated and the only artifact you have to take care of is
noise, so you only need to increase the pixel samples.

Thanks