Inverse Kinematics

[Springheel]

When the time is right it doesn't look like it will be that hard to get our AI to walk properly up stairs. I'm not going to do this now because the rigging on our AI is about to change, but it looks pretty straightforward to set it up. http://www.iddevnet.com/doom3/walkik.php

[ascottk]

There's already ik code in the def files. This one's from the elite guard:

 

	"ik_numLegs"					"2"
"ik_footSize"					"4"
"ik_waist"						"Body"
"ik_hip1"						"Lupleg"
"ik_hip2"						"Rupleg"
"ik_knee1"						"Lloleg"
"ik_knee2"						"Rloleg"
"ik_ankle1"						"Lankle_r"
"ik_ankle2"						"Rankle_r"
"ik_dir1"						"Lknee"
"ik_dir2"						"Rknee"
"ik_foot1"						"Lball_r"
"ik_foot2"						"Rball_r"

[Ishtvan]

Cool, yeah it looks fairly straightforward, the only one that might need some change in the model is the ik_dir joint telling the knee which way to bend, not sure if there's already a convenient joint for that.

 

There's also a less-well documented "arm IK" within the SDK, but I don't know to what extent it's implemented in D3.

 

@AscottK: True, but usually those just give a crapload of warnings about the joints not existing. I think it was copy/pasted from the Imp, might have to be modified for our skeletons.

[ascottk]

Hmm, yeah. Odd's models have different names. Since I'm working on the builder guard, here's his legs/feet joint names:

 

"Hips"

"LeftHips_Dummy"

"LeftUpLeg"

"LeftUpLegRoll"

"LeftLeg"

"LeftLegRoll"

"LeftFoot"

"LeftToeBase"

"joint3"

"joint4"

"RightHips_Dummy"

"RightUpLeg"

"RightUpLegRoll"

"RightLeg"

"RightLegRoll"

"RightFoot"

"RightToeBase"

"joint5"

"joint6"

 

I have no idea why there are leg rolls There's also some generic joints in there whose function is not known to me Maybe they're knee related.

[Springheel]

There's already ik code in the def files. This one's from the elite guard:

 

Yeah, those are just copied from the D3 imp. They don't work. They need to be replaced with the appropriate joint names. I took a stab at it a few days ago but I was just guessing since our AI seem to have twice as many leg joints as the D3 models.

 

Anyway, once we have our new, updated rigging it should be easy to track down which is which.

[oDDity]

Those buidler guard bones are the default bone rig required by motion builder. After that early rig I changed it to a simpler and more standard system.

You'd probely be better re-rigging it with the standard skeleton.