Planetside Software Forums

General => Terragen Discussion => Topic started by: cyphyr on January 21, 2015, 04:26:55 PM

Title: Render Layers 2D Motion Vector usage
Post by: cyphyr on January 21, 2015, 04:26:55 PM
Hi guys

One of the files that can be rendered out within "Render Layers" is the "Surface 2D Motion Vector" aka myfile.tgSurf2dMotion.0001.exr.

This will generate a colourful file representing relative motion in different directions by varying colours. (test.tgSurf2dMotion.jpg)

Can anyone advise on how to use the motion vector file to simulate motion blur in either After Effects or Nuke.

Ta muchly :)

Richard

Title: Re: Render Layers 2D Motion Vector usage
Post by: Matt on January 21, 2015, 06:23:17 PM
In Nuke it's pretty straightforward. The Red and Green channels are U and V motion in pixels, and the data can be used by the Vector Blur node without needing to massage the data. If I recall correctly, you probably want to shuffle (or shufflecopy) the rgb.r and rgb.g components into the motion.uv channel, then make sure the Vector Blur node uses motion.uv. You might even be able to do it directly from the second input. I forget exactly what you need to do with the offset and multiplier, but offset should probably be 0 and the multiplier should be 1.0 if you want the motion blur to respect the motion blur length that was set in Terragen's camera.

Here's a reply I just made to another question about motion vectors, which might be relevant:

http://www.planetside.co.uk/forums/index.php/topic,19506.msg191737.html#msg191737

Matt
Title: Re: Render Layers 2D Motion Vector usage
Post by: cyphyr on January 22, 2015, 01:49:57 PM
Thanks Matt :)