5 Replies Latest reply on Jun 17, 2012 7:23 AM by Mylenium

    Dealing with speed & velocity in a 3D space.

    quinnygoth Level 1

      Hello everybody.

       

      I've recently posted a question regarding the project I'm currently working on but this is a new issue so I thought I'd start a new discussion.

       

      I'm making a music video. In this music video the audience is taken through a "vortex" like tunnel in space. Similar to this;

       

      http://www.youtube.com/watch?v=VwjfrAn0hnA

       

      However, in my video the vortex is made from a number of audio waveforms, generated with After Effects' Audio Waveform feature, which have been precomposed, and made in to a tunnel using After Effects' CC Cylinder feature.

       

      I've made the composition and the waveforms that make the vortex 30,000 pixels in height, which, after the CC Cylinder feature has been applied and the X axis rotation adjusted -90 degrees, translates to depth.

       

      I created a camera layer and parented that to a null layer. I positioned the camera at the opening to the vortex (start of tunnel/top of cylinder), at the start of the main comp, via the Z axis and made a key frame. I go to the end of the comp, place another keyframe, and move the Z axis position until it comes to the end of the vortex (bottom of cylinder).

       

      I rammed the whole thing in 1/4 resolution because I'm on a standard spec MacBook Pro and it can't handle the precomposed waveforms comp size (30,000 pixels) in full resolution (There's 10 precomposed waveforms in a precomp. So ten precomps that are 30,000 pixels in height). I play it through and the camera isn't travelling through the vortex at my desired speed. I need it to look like the audience are travelling through the vortex much faster.

       

      Currently the vortex is just a straight cylinder. However, I intend on using various displacement maps to add turns and dips to the vortex, as well as adding various other bits and pieces, such as particles.

       

      So my question is: how can I change the velocity of the camera so I can get it the speed I want?

       

      Note: if anybody thinks they know a better way to approach this project, even if the methods are totally different I'm all ears.

       

      Thanks!

        • 1. Re: Dealing with speed & velocity in a 3D space.
          Rick Gerard Adobe Community Professional & MVP

          Other than putting the keyframes for the camera move closer together I'm not sure how you make the camera go faster.

           

          I'm not sure why you need such huge pre-comps. If the camera is moving quickly then motion blur would fix any pixelization problems.

           

          Also, there are many ways to make a vortex that are more efficient than stacking up a bunch of CC Cylinder effects. I'm not sure how you'd use distortion mapping to move the cylinder into a cone. It's just not built that way.

           

          I'd take your audio wave forms comps and put them in a comp that's maybe 3 times the height of your main comp and use that for your tunnel. You'll only need one. Then create a camera with a very wide lens (say 15 or 10º) and fly that through your tunnel by animating the Z position of the camera. The wider lens will give you a straight tunnel that looks very long when it isn't.

          1 person found this helpful
          • 2. Re: Dealing with speed & velocity in a 3D space.
            Mylenium Most Valuable Participant

            Well, in so many words: scrap the idea. It's never gonna look anything but dull/ awful. There are too many limitations here like CC Cylinder not calculating motion blur and your only getting into trouble with humongously large layers. Even that idea with the waveform is not that great - who's gonna see it, anyway? You're to bent on making this "real". If all you want is some wobbly patterns as in the video, then the answer is so insanely, ridiculously simple it will make you laugh like a mad man: Fractal Noise followed by the Polar Coordinates effect. Animate the offset of the Fractal Noise and it will look like a flythrough. You can even stack multiple layers and by shifting them one against the otehr create "curves" - good old parallax scrolling as it was used in games a lot. And I'm sure your waveforms fit in there somewhere as well, it may take just some tweaking. In any case it's a lot more resource friendly and controllable.

             

            Mylenium

            1 person found this helpful
            • 3. Re: Dealing with speed & velocity in a 3D space.
              quinnygoth Level 1

              Thanks for the reply Mylenium. In regards to the video looking dull & awful, I'm not posting here to ask for help in regards to the stylistic or conceptual merits of the video. The concept has been fully thought out and it fits well with the record artwork and the song itself. Then again, you might be correct, and it might look rubbish, but I'd rather make it and see then not make it and never know.

               

              I'm not trying to make a vortex like the one in the video I linked. I've watched a couple of videos on how to make one like that so I'm aware of how it's done, but thanks for explaining anyway.

               

              "You can even stack multiple layers and by shifting them one against the otehr create "curves" - good old parallax scrolling as it was used in games a lot."

               

              Could you elaborate here for me please? What do you mean stack the layers? I've just checked the Wikipedia on parralax scrolling but I don't really understand.

               

              The waveforms are an important part of the video. I've set the duration, height, thickness and amount so that they can be seen by the audience when travelling through the vortex. They repsond to the music. It looks cool and it's part of the concept.

              • 4. Re: Dealing with speed & velocity in a 3D space.
                quinnygoth Level 1

                Thanks for the reply Rick. The reason I thought it best to have big precomps is because I need the waveform vortex to last the whole length of the video. My thinking was the bigger the precomp, the more vortex the camera needs to fly through in the 3 minute time frame, making it look like it's travelling faster.

                 

                "Also, there are many ways to make a vortex that are more efficient than stacking up a bunch of CC Cylinder effects. I'm not sure how you'd use distortion mapping to move the cylinder into a cone. It's just not built that way."

                 

                Could you possibly explain these other ways to make a vortex? Or link me to an explanation? I've watched a few tutorials on displacement mapping. I've never used it before. However from what I've seen I thought I'd be able to use it to "bend" the vortex at certain points, creating dips and turns.

                 

                "I'd take your audio wave forms comps and put them in a comp that's maybe 3 times the height of your main comp and use that for your tunnel. You'll only need one. Then create a camera with a very wide lens (say 15 or 10º) and fly that through your tunnel by animating the Z position of the camera. The wider lens will give you a straight tunnel that looks very long when it isn't."

                 

                The issue I have is not the tunnel looking long, but, the tunnel not being long enough for the camera to fly through at the speed desired. I can put the end keyframe in the middle of the timeline and it makes the camera go through the vortex fast, but there's still another half a song afterwards.

                 

                Thanks

                • 5. Re: Dealing with speed & velocity in a 3D space.
                  Mylenium Most Valuable Participant

                  Simply shift the layers slightly left/ right, each with slightly different values. If you have a few of them behind each otehr and the offsets folow more or less a sinus/cosinus or exponential curve, it will look like a curving tunnel. Could be automated using some expressions, of course. Anothe idea would be to exploit a particle system like Particular with a ring like emitter or even a point emitetr that spits out ring particles. By using the forces and varying particle properties over time you can also create some interesting stuff....

                   

                  Mylenium