Cineversity

I have been using the same car model for years for various productions. The model has been great but for some reason I have always had a recurring issue with the tires. For some reason the tires will rotate 360 degrees at 90 key frames, if I shorten the animation to say 50 key frames the geometry stops rotating. I have always wondered why? This may be something obvious but I have never been able to figure it out. Am I missing something? I have never had this issue with any other model I have created personally, or purchased.

I am posting this out of curiosity more than necessity so no rush. Thanks in advance – Devoted

File attached.

Having issues uploading the zip file.

Error Message:  The file you are attempting to upload has invalid content for its MIME type.

Not sure why I am getting this error, its only a 1MB zip file

Hi Devoted,

I have that “Mime” thingy from time to time as well. No idea if some extra “dot/periods” in the name will cause that. Sorry. I use Drop-Box, or Amazon Cloud for that, others have other cloud services, most allow for some GB for free.

Please try again with the zip, perhaps rename it to,e.g., devoted1.zip

I will have a look into it.

Talk to you soon.

Sassi

I uploaded it here

http://www.devotiondesign.com/C4D/Tire.zip

Thank you!

Hi Devoted,

I got your file, thanks for the extra effort.

I’m not clear what you communicate with the “...if I shorten the animation to say 50 key frames the geometry stops rotating.”

Do you mean a) you shorten the scene time to 50 frames and not changing the keys, or b) you changing the key frames so they are only 50 frames apart and outside of that there is no rotation? (See image)

The question is only to understand you clearly, so we can solve that mystery.

Can you send a file where you have set it to 50 frames and tell me where you expect to have motion.

Cheers
Sassi

Try moving the last key frame from frame 90 to 50 then press play. Does the tire geometry stop spinning?

The tire is intended to rotate 360 degrees as if it is rolling. It rotates at 90 frames but doesn’t at 50. I would expect it simply rotate faster not stop. The axis keeps rotating but the geometry does not.

Thanks

As in my image above? Animation is change over time. Between frame zero and frame 50 (horizontal axis) the value (vertical axis) changes. Time and value changes and lead to motion. After frame 50 there is only time, no change in value, no motion.

The two dots at frame zero and 50 show the keyframe. The line between these two is the interpolation (linear in this case). After frame 50 is no line as there is no further key frame after frame 50. Nothing to interpolate.

Do I describe it as close to your problem as possible. If not, what do I miss?

For this demo I am only having it rotate once. If I play the timeline from 0 to 50 the tire does not rotate even though it is keyed to rotate. If I keep everything the same and move the key frame from 50 to 90, then play the time line from 0 to 90 it rotates. What happens when you do that?

Thanks

I’m not a step further, as you don’t answer questions that I have asked you. Do you change the keyframes or the preview time. Be precise.

The file you have send is playing fine—if I play from 0 to 50 or 50 to 90.

Please send the file exactly as you have the problem.

Updated file http://www.devotiondesign.com/C4D/Tire2.zip

This file, when I hit play the tire does not spin even though it is keyed to spin once.

Can you see the tire geometry actually rotating in this updated file? All I did was drag the keyframe 90 to frame 50.

Thank you. Sorry this is a hassle.

Devoted,
Exactly, between 50 and 90 9or 90 to 50 as you say), there is no change of the information, the Information is here the rotation in degrees. With that, the tire is supposed to stand still. This is how it should be!

Again, animation is change of values over time. No time change—no animation. No value change, no animation.

There is a keyframe on frame 50. So this keyframe value, is then all there is to it. Let me say it clearly:

Frame 50= 360º
Frame 51= 360º
Frame 52= 360º
Frame 53= 360º
etc
Frame 90= 360º

As after frame 50 comes no different information, that is all there is 360º

You can set the interpolation to continue after the last key frame, but that is a complete different idea, you project the animation change from the past to the “future”. But in your scene, after frame 50 (again) there is no information change. Hence there is a yellow line between the two dots (F-Curve window) to show case that, no line no change. (If you use “Track After” then the line will be black, and indicates an “extrapolation” of the keyframes before.

You need to set a keyframe to frame 90 with a new and DIFFERENT value than on frame 50, otherwise it will just be there, no P.R change an it is correctly doing nothing.

Let me know of that made sense. It is the basic idea of animation.

Years ago I had a classic animation artist on the Event booth, asking about a similar question. She was not certain how to tell the computer all the “in-between” poses. That is the interpolation. Inter as in between the key positions. After Frame 50 there is no Key position—so it repeats.

(BTW, to make a tire run one time around, the 0º and the 360º are the same.If you make a loop, this would introduce a small stop. In the moment we are clear with the Keyframes, I think it would be great if we could clear that as well.)

You must not be seeing what I am seeing, thus you must not be having the issue for some reason. I understand animation I started keyframing in flash back in 97. When you play the scene Tire2 from frame 0 to frame 50 does the tire spin?

Key Value 0 = 0 degrees
Key Value 50 = 360 degrees

The tire should rotate 1 time, correct? I know it will not rotate after frame 50. Does the tire rotate 1 time for you? It does not for me.

Later tonight I will record my screen and upload a video.

Thank you for all your help.

Hi Devoted,

Sorry, I didn’t intended to place a label on you, “can’t animate”. You never gave me an acknowledgement for what I wrote, nor answered questions (e.g., a) or b).  So, I assume, as a good instructor, that there might be the black spot or let’s call it the misunderstood. That’s all.

I think I wrote three times already that the tire is rotating during the first 50 frames here. 

It is clearly not the case for you, and that is then, with no doubt a case for the support. I can’t do anything else then here. But please read on…
You wrote “For some reason the tires will rotate 360 degrees at 90 key frames”, which indicates for me, that no filter (e.g., no animation) is working here. So, that is strange, and nothing I can solve.

So, let’s do the next thing: Pick any single polygon of the tire, when it is selected, then pull it out. Now scrub the time-slider again. Can you see how it is moving?

One more, in the Editor view, set the Display to “BOX”, scrub again, is the box rotating?

I can see it rotating. If you can’t, please contact the support, but I guess it does rotate, including the geometry. All fine?

All the best

Sassi

Thank you for your time and please do not think that any of my posts are intended to convey any attitude or disrespect toward you. It is definitely not intended. I appreciate all you have done, are doing and will do in the future for me! I have nothing but gratitude.

This is just a really weird problem.  As stated I have used this model for years and have always had the same issue in C4D13, 14, 15, 16. This issue has also survived through 3 different machines, all fast but my current build is the fastest. Dual Intel E5-2620, Nvidia K5000, 64GB RAM. Windows 7 Pro

Please view the video and let me know your thoughts.

Thank you very much!

http://www.devotiondesign.com/C4D/TireProblem.zip

Hi Devoted,

I have nothing located in our discussion that I would take in a negative way. In the past decade I have introduced so many people to 3D or supported their growth to a certain degree, that I know, we all have a very mixed bag of skills. I never like to underestimate anyone, but I have to explore the problem that is requested to solve, which can have many sources. So, I try to focus not only on the application.

Please read my last post, please all the way through, or just the line in “bold”. BTW, if that doesn’t help, how about the Physical Render and Motion Blur ;o) IF the geometry isn’t moving, then it should have no MB. But I’m certain you will see that the frame 0-50 is the exact time to freeze the appearance. A little bit different and you would get teh Wheel backwards effect, as seen in movies from time to time.

Let me know if the two examples of post #12 will work for you and if that clears up the problem. I’m certain it will.

Have a wonderful evening. (I have watched the movie, same here, if the display is set up that way)

Sassi