Living without IK

LynceusGlaciermaw

New user here! I'm working with my wife to make games using Spine animation.

We're having some trouble. Now unlike what marketers seem to think, putting extremely useful features behind a paywall does not in fact cause more money to magically appear in my bank account to pay for it; therefore, I've got to live with the feature set that the Essential license gives me. (Don't get me wrong... I don't begrudge the developers the price tag for their hard work. I just can't afford it!)

To that end, I've been trying to live without inverse kinematics. Idle and dance animations have felt utterly impossible to reliably create without being able to anchor the foot bones in place - I've been scratching my head at how to work with such a huge handicap. I was under the impression that Spine hasn't always had IK available, so I thought techniques must exist.

Does anyone have any advice? I'd love to hear anything from a veteran. 🙂

24andahalf

Remove all translate and rotation keys from the feet then just don't move them if you want them planted in place. If the feet are parented to the legs then I'd say you haveta key the feet using their translation co-ordinates from their starting pose so they always stay in place everytime you move the feet. That's my hacky approach to some game anims I'm doin in another window right now anyway.

I've got about 16 years using Flash and had to handle 100s of characters walking, dancing, fighting etc all without IK. I have the full version of Spine and I'm still not using IK on the feet/legs because I want to have complete control over them and I have trust issues apparently 😃

Nate

Many animators prefer FK. Many animators start with FK, move to IK, then back to FK. Of course, great animations can be done with FK, IK, or both.

An IK target usually moves in straight lines which can lead to FK giving more natural movement. On the other hand, some movements are nearly impossible with FK, such as legs pedaling a bicycle.

FWIW, in this video at 12:00, I show how to adjust curves and bones to prevent feet penetrating the ground for a run animation without IK:

I'm sure better animators than myself have more advice. You aren't limited to Spine-specific advice, I suggest doing a broader search for FK animation approaches.

Søren

If you use Ghosting you will be able to see frames before and after your current frame and use that to adjust the position of your bones to get rid of feet sliding.

LynceusGlaciermaw

Thanks very much everyone! I'll try to put all of this to use. My wife has been making great strides in learning the program and this can only help.