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wes

How Motion Capture Works for Locomotion

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At the recent motion capture shoot we decided to recapture the female locomotion. This includes walk, jog, and sprint, as these are the speeds you can move in the game. The previous data we captured for the female was a bit off. We simply were not happy with how it looked. The new data is much cleaner and looks more fluid and natural. The gif below is a looped gif, so there's a brief hiccup in the locomotion. That was a symptom of the gif, not the raw data. It will be perfect in-game. 


 


The trickier parts for locomotion relates to starts/stops and blends. Let me explain. When you press forward on the thumbstick (on a controller) and the character was standing still, then should begin moving forward. If you barely press forward, they walk, if you push harder they jog. If you click in on the thumbstick, they sprint. But when we capture these movements they are independent. We ask the actor to walk and we capture that. Then we ask them to jog and we capture that. Lastly they run and we capture that. Then we cut the data down to just one cycle each. If it's a walk, one cycle would be each leg moving forward, and that's all we need. Same for jog and sprint. Once you have those cycles you have to then think about starts and stops. So with the same data, we pull the frames from when they first began the locomotion (walk, jog, and sprint) and we pull that frame. Same for when they stop. Next we pull the few frames that are just between the moments of starting and then top speed. Again we pull blends from all 3 cycles (walk, jog and sprint).


 


female_run_cycle.gif


 


 


With that said what you end up with is three starts, three stops, three blends and three speed cycles. Each only a few frames each. This allows the player to move the thumbstick and see the character react appropriately on-screen. It's a very time consuming process and it takes a real artist to get it right. If your data is off by one frame, it throws the whole cycle off. You'll get unnatural movement. Next you have to think about timing the frames to match foot speed. If this is off, you get "foot sliding". This is an effect that looks like the character is skating. If the timing of the locomotion is slower than the foot speed (think of it like miles per hour), then you get foot sliding. Same issue if the locomotion is too fast. It's very delicate. Artists/engineers are working in centiseconds within a frame. 


 


So the next time you play a game and you notice your character walking, running, etc. Now you have a brief background on what it takes to make that look correct. 


 


-W


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At the recent motion capture shoot we decided to recapture the female locomotion. This includes walk, jog, and sprint, as these are the speeds you can move in the game. The previous data we captured for the female was a bit off. We simply were not happy with how it looked. The new data is much cleaner and looks more fluid and natural. The gif below is a looped gif, so there's a brief hiccup in the locomotion. That was a symptom of the gif, not the raw data. It will be perfect in-game. 

 

The trickier parts for locomotion relates to starts/stops and blends. Let me explain. When you press forward on the thumbstick (on a controller) and the character was standing still, then should begin moving forward. If you barely press forward, they walk, if you push harder they jog. If you click in on the thumbstick, they sprint. But when we capture these movements they are independent. We ask the actor to walk and we capture that. Then we ask them to jog and we capture that. Lastly they run and we capture that. Then we cut the data down to just one cycle each. If it's a walk, one cycle would be each leg moving forward, and that's all we need. Same for jog and sprint. Once you have those cycles you have to then think about starts and stops. So with the same data, we pull the frames from when they first began the locomotion (walk, jog, and sprint) and we pull that frame. Same for when they stop. Next we pull the few frames that are just between the moments of starting and then top speed. Again we pull blends from all 3 cycles (walk, jog and sprint).

 

attachicon.giffemale_run_cycle.gif

 

 

With that said what you end up with is three starts, three stops, three blends and three speed cycles. Each only a few frames each. This allows the player to move the thumbstick and see the character react appropriately on-screen. It's a very time consuming process and it takes a real artist to get it right. If your data is off by one frame, it throws the whole cycle off. You'll get unnatural movement. Next you have to think about timing the frames to match foot speed. If this is off, you get "foot sliding". This is an effect that looks like the character is skating. If the timing of the locomotion is slower than the foot speed (think of it like miles per hour), then you get foot sliding. Same issue if the locomotion is too fast. It's very delicate. Artists/engineers are working in centiseconds within a frame. 

 

So the next time you play a game and you notice your character walking, running, etc. Now you have a brief background on what it takes to make that look correct. 

 

-W

 

 

Some have reported that the gif I posted isn't working properly. Here's a direct link to view: http://imgur.com/RmCdjQT

BlackWidowofLaPorte likes this

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Following this game has taught me so much about game development; I never thought about how much work people had to do to bring a game to life. I have a newfound respect for you guys and the whole game development industry. Thanks so much for all the hard work you guys do to make this game a reality for us. You guys are da real MVPs!

wes and thatdudescott like this

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Awesome posts, love the insight you're giving to people on game development. You guys seem to be taking it all very seriously and love telling people just how hard even the simplest things can be in game development. 

 

Again, thanks for being so in-depth with the intricacies, can't wait to see counselor gameplay!

wes likes this

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Like others I really love these posts and think they're good for those people that don't understand how development works and why things take so much time. Thanks to Wes and the rest of team. You're doing an amazing job.

wes likes this

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Kind of like editing frames in Flash tweeting the animations to line up with the frames with multiple layers but way way more complex I bet

 

Now is that gif link you showed the new one or the last unsatisfied one?

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Kind of like editing frames in Flash tweeting the animations to line up with the frames with multiple layers but way way more complex I bet

 

Now is that gif link you showed the new one or the last unsatisfied one?

 

That gif I posted is the corrected sprint locomotion. :)

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That gif I posted is the corrected sprint locomotion. :)

Nice! Also good you were able to do it while doing single player mo cap! My brother worked at that studio years ago he designed the clothing skins for hot shots 2 golf

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you guys are missing the real life bounce of a woman. other then that looks great

kind of what i was getting at. mocap will never get that i as far as i know.

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