6 Replies Latest reply on Nov 7, 2015 10:59 AM by asinclair@ithaca.edu

    How to have one point in a shape follow (and contort) across path

    chrisf88472466

      Hi,

      I have attached 3 stills to help me explain my issue.

      1.png2.png3.png

      I have a red shape layer that I would like to move smoothly across the screen following live action.  Right now the shape comes to a single point (at the top of the cone), which I like.  My problem is that the red shape bounces around (because I placed the top point manually, like a fool). 

       

      Is there a way to draw an arc path, where the top point is, and have that point follow the path smoothly and accurately, without moving the whole shape (just changing the shapes size and angle).

       

      Let me know if this didn't make sense or you need clarification?

       

       

      Thank you x1million.

        • 1. Re: How to have one point in a shape follow (and contort) across path
          Szalam Adobe Community Professional & MVP

          You could track the listener device thing in his hand, apply the tracking data to a null object. Parent your shape layer to that null. You may need to manually animate the curved part by the dish a bit, but this should get you pretty close.

          • 2. Re: How to have one point in a shape follow (and contort) across path
            chrisf88472466 Level 1

            Ahh yes, I should clarify.  I already have the shape layer parented to a tracked null (based off his rotation) which is how most of the movement is happening. 

             

            I then did some cleaning up on the curved parts of the dish.

             

            Is there a way to have another parent?  And have it be for JUST that one top point?

             

            Again, let me know if this made sense or what I should take screen grab of.

             

            THANK YOU!

            • 3. Re: How to have one point in a shape follow (and contort) across path
              asinclair@ithaca.edu Level 1

              Yes there is. Create a Null object. Then create a solid layer comp size (or bigger if the arc is bigger). In that layer draw your path. Use only 3 points in your bezier curve to draw the path. Select the Mask path and COPY it. Select the Null object, click P to open Position and PASTE it. The Null object now follows your path.

               

              Next create your shape. I can see your current shape has too many vertices at the base of the triangle. This makes it time consuming to animate. Use only 3 vertices to create the base curve so you only have 3 point to animate or adjust. Now MOVE the ANCHOR point of your shape to the apex of your shape.

              Create an expression on the POSITION of your shape layer so you can access the pickwhip.

              Finally using the pickwhip enabled by the expression drag it to the POSITION of the Null object, that's it.

               

              Now your shape should follow the arc path (based on the anchor point of the shape) and all you need to do now it to keyframe the 3 base vertices around the parabola of the mic.

               

              Let me know if this is clear. You can also contact me via Karen who has my mobile phone,

               

              Good luck

              • 4. Re: How to have one point in a shape follow (and contort) across path
                Rick Gerard Adobe Community Professional & MVP

                Here's what I would do.

                1. Track the movement of the microphone using AE's tracker with Position, Scale and Rotation selected:
                  Screen Shot 2015-11-04 at 10.55.21 PM.png
                2. Apply the track to a to a tracker null
                3. Position your shape layer where you want it on the first frame of the comp
                4. Move anchor point of the shape layer to the tip of the microphone
                5. Parent the shape layer to the null
                6. Set a rotation keyframe (Alt/Option + r) keyframe for the shape layer at the first frame of the project
                7. Move to the last frame of the project and adjust the rotation of the shape layer to fix any problem with the rotation of the shape layer
                8. Move to the middle of the timeline and verify that rotation is correct then make any adjustments needed (if your track is good one or two adjustment keyframes will be all that is necessary)
                  Screen Shot 2015-11-04 at 11.10.25 PM.png

                You're done.

                 

                This is the easiest solution. Anything involving an expression and the look at function or trying to position a vertex point to the motion path would be more work and require at leas as many steps. The trick to making this work is accurate positioning of the anchor point for the shape layer and a good track. If AE's built in tracker will not work you could also use Mocha. The only difference in the workflow is step 1 and 2. Track in Mocha, Copy and the tracking info and paste it to the null.

                • 5. Re: How to have one point in a shape follow (and contort) across path
                  Mylenium Most Valuable Participant

                  You could have just used the Beam effect and masked out one of its ends. It's funny how so many smart people can miss the obvious. Yopu know, half that tracking could be eliminated this way with some simple parenting and a pickwhip expression...

                   

                  Mylenium

                  • 6. Re: How to have one point in a shape follow (and contort) across path
                    asinclair@ithaca.edu Level 1

                    The beam is a good idea but you still would have to animate the mask at the bottom of the beam.