View Full Version : Animating a playing guitar

10 October 2005, 03:14 PM
How would you animate the strings of a guitar beeing played?

I want to have the string vibrating with the vibration starting at the respective fret going down (with beeing strongest over the "hole" in the body of the guitar) and fading out as it reaches the end of the string. A little bit hard to explain.
Just imagine a guitar string beeing played by an invisible hand.

10 October 2005, 08:49 PM
You could use posemixer and animate the String between two extremes.

The extreme poses can easyly made with and FDD
see attached file.


10 October 2005, 09:31 PM
you could also just use a formula deformer (with it's basic formula) or a wind deformer, and a restriction tag with a weightmap along the string.

10 October 2005, 09:32 PM
i'd do it with basic xpresso tricks + loft nurbs.. to explain:

| = where to put circle spline, first one is the head nut, 2nd is fret, 3rd is middle of wave, and last one is bridge, so just oscillate the 3rd one, and use xpresso to move the 2nd and 3rd ones according to the fret position (so that 3rd is always 1/2 the distance of 2nd away from bridge), if you need accurate natural or pinch harmonics as well, this should be easy enough to modify to account for those as well :)

10 October 2005, 09:58 PM
here's an example of what i was suggesting (just hit play then hit the "Pluck!" checkbox on the cylinder/string object).

10 October 2005, 10:37 PM
here's an example of what i was suggesting (just hit play then hit the "Pluck!" checkbox on the cylinder/string object).awesome work :D

.. however, when a guitar string is plucked, it plays a 1st harmonic wave:

unless of course you play a natural or pinch harmonic, in which case you will achieve an nth harmonic (although proper pinch harmonics i can imagine are notoriously annoying to simulate). wind gives a pretty random looking result, although it might not be bad if physical accuracy isn't too important :)

10 October 2005, 10:54 PM
i was presuming he wanted something a bit more cartoony as realisitic normal guitar string vibration would really only be visible as a blur unless it's a slowmo effect (though thinking about that you could also maybe fake the effect by making a slightly strobing transparent texture that blends in as you flatten out a string sideways for a more realistic effect without the renderhit of doing motion blur). if you want you can reduce the frequencies and randomness in the wind effector too to create a more accurate effect (with no randomness you get a pure sine wave from wind).

10 October 2005, 10:24 AM
Wow - this are some great techniques!

I think the Pluck! Xpresso can do exactly what I want with modified Wind-Prameters but I'll check out on the Loft-Xpresso thingie too.

Thank you very much indeed.

10 October 2005, 12:21 PM
Ignore this post, discovered answer to my question.

10 October 2005, 11:04 PM
mdme_sadie, is there an easier way to animate your Pluck-Xpresso than what I do right now?

I need to set three keys for one pluck (frame1 Off, frame2 On, frame3 Off), because apparently when I key a number of "On"s I get a constantly vibrating string. It displays the Pluck-Field as off but it works as if it's on (supposedly because the "always on" f-curve overrides the "shut down" function in the expresso).

Not a big problem though - I'm just curious.

Another thing I'm curious about is: How can you controll a Coffee variable with a User Data field? What I'd like to do is wire the 0.95 value you used for dampening the effect to a slider in the HUD, so that I can easily access this option. I haven't worked with Coffee in conjunction with Xpresso yet.

And just if anybody is interested, here's the guitar this will be used on:

10 October 2005, 11:14 PM
Forget the User Data to Coffee variable question, I just found out that you simply add a Real as an input for the Coffee node :D

11 November 2005, 12:57 AM
Hey, I know that Response by 3dattack will be able to do this, but, in the meantime, is there a quick way to get the strings to repond to music? That is, vibrate to selected music/segments of music?

CGTalk Moderation
11 November 2005, 12:57 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.