Wednesday, December 1, 2010

Style vs. Technique

This is a very dear topic to me, I just wish I was able to output my through about it efficiently.

I recently posted a link to a paper and video in twitter:
Situation Agents: Agent-based Externalized Steering Logic
I got a reply that the results are not very realistic. And it is very true, especially the formation examples look quite unrealistic indeed.

But compared to what? Some generic situation in real-life? Our generic assumption about how things should behave? Maybe you were in a similar situation yesterday and you comparing the video to that.

There was a one important lesson I learned from art school: when you critique someone's work, you better be able to explain your point of view. You have to define your point of view, your artistic vision and potentially references to existing methods.

In order to have a good critique over the above example both the presenter as well as the commenter needs to point out their artistic point of view. Otherwise the discussion is pointless.

More scientific way to justify your point of view is to hypothesize, collect data, build a model, and compare your method against it. This approach is well executed in the following research:
A Synthetic-Vision-Based Steering Approach for Crowd Simulation
When the model is tuned based on the input data, the output looks and should look much like the data that was used to tune it.

My critique to the above method is that can it reproduce different kind of styles? For example if two actors would act out exaggerated situation where and a nerd and a bully avoid each other, could the method capture that style?

In my humble opinion in order to critique a technique you either have to have an artistic point of view (one that you can also explain to others) or if you compare things to realism, you better have good data! Otherwise the discussion will be just bike shedding.

Seeing potential of a method is not easy either. Ken Perlin showed an interesting picture pair during talk at Paris AI Conference this year. In one picture there was a raytraced marble sphere, picked from his original noise paper, on other picture there was a shot from a movie which had beautifully rendered stormy ocean, which was build using his noise function.

Examples are generic and try to show off the technicalities of the technique, but it takes an artistic vision to turn a technique into something worth watching.


  1. I think it's also okay to take feedback from people without clear reasons for their opinions. They might be wrong, or it might really be just a different opinion, but I find people also often have some value in their gut reactions. No need to enslave oneself to unsubstantiated statements, and clear evidence is valuable. But that doesn't mean other feedback is always meaningless.

  2. I think it's fair to judge something on its results. How else can it be judged? If it's not realistic then don't show it with human agents. Are we supposed to guess at its potential? The technique seems to avoid non-existent future collision unless he can show differently it seems safe to assume that is a deficiency of the algorithm - either that or he's showing too early