Motion Vectors (for animated textures), How do you generate them?

Absolutely, as soon as the kinks are worked out I’ll share it. I am almost done, right now it requires a good amount of magic number fiddling which I would like to remove, although in the interest of keeping it as cheap as possible I might just leave it, the thinking being that you spend 15 minutes dialing in your numbers and then at least for that flipbook you are kinda done. Seems a reasonable trade for ease of use. On most projects I’ve worked on it’s not like you have 50 different flipbooks to dial in, you use the same 5-10 over and over.

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Been attempting this, can’t get it right. Any chance I could see your node set up?

Hi Junco, here’s a basic example you can start with.

Of course, you can change input UVs and other things as you go.

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How’s it coming along :smiley:

Thank you, the visual helps tremendously. :slight_smile:

Hi Mederic, Have you seen this ?

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i’m overwhelmed but desperate to incorporate this into our mobile (unity) pipeline
looks like the easiest (artist friendly) most accessible method is

  • explosion in blender,max,popcornFX or maya, (many simple tutorials online we can learn from)
  • output to FacedownFX (slate editor)
  • beg shader engineer to incorporate into toolset

my mission was to grab an explosion and i can take two avenues

  • sample the whole sequence
  • take 4 images, try to loop it (2x2)

went with a simple 2x2 to see if I can figure it out

there must be some way to append a 5th image to be used as the final flow but don’t know what to do next,…actually I feel like I haven’t learned anything

Are there anymore detailed accessible methods out there? Klemen Lozars is still too involved for me to pickup
I tried googling “Optical Flow Gnomon” or “Lynda” don’t get anything particularly useful

what would be the current next steps in terms of researching?

obviously the ideal answer I want - popcornFX or Blender would have an Optical flow checkbox

  • I make explosion
  • hit check box
  • render two sprite sheets
  • plop into engine shader

Is this a pipe dream?
is my only single package solution at the moment Houdini?
Is it a single package solution?

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Right now Houdini is the only single package solution.

The other solutions is Slate, Twixtor and potentially NukeX.

Klemens writeup is the only non Houdini one I’ve seen.


thanks man. im trying fraps with Unity -> VLC -> image sequence + Slate

I mean…it’s a start.


  • beginning frames are fast …not enough visual parity to get flow
  • smoke is so slow and using too much texture space, it could be rendered on 2’s

I can get visual parity with playback_speed but Slate would need a “remap” curve to process the sequence blending X:1 and the curve would also process smoke frames at higher ratios to throw out redundant visual data… I’m imagining sequences need to be authored with normalized pixel movement not real-time some type of optimized distortion time analogous to a models UV’s with unified pixel density - Am i making myself clear?
but all that doesn’t exist so what can we do?..

could I just break it up into 2 sprites and 2 emitters? would that work?

  • one is the explosion using additive
  • one the smoke using alpha

hmmm not a bad idea? this might allow me to optimize the smoke into a 256 with 3x3 (9 images)
and a 512 (4x4) for the explosion

Hi, I’m curious if anyone else is running into the issue of blockyness when the flipbook is played back more quickly? Has anyone been able to find a solution for that?

Hey everyone, at Tuatara we are super happy to announce that we have released a one-click motion vectors baking tool : TFlow - Motion Vector Generator