• Adobe After Effects Expressions

  Slider that scales the slider value to the comp duration

  Posted by Michael Stark on January 9, 2014 at 9:45 pm

  I’m basically trying to make scrolling text, that i can re-use based on a comp’s duration.

  I have one slider that controls the vertical position, but I want to add another controller that scales it’s slider range from 0 – the end point.

  That way I can say that the other controller’s “2nd keyframe” will happen on “specified frame”.

  I’m not the best expression person (I fancy the pickwhip) so trying to figure this out is just hurting my brain.

  Any help is much appreciated.

  Philip Bowser replied 12 years, 3 months ago 2 Members · 3 Replies
• 3 Replies

• 

  Philip Bowser

  January 10, 2014 at 1:28 am

  So are you trying to have text automatically scroll from one position to another over the course of the comp’s duration?

  Would something like assigning a “Start Vertical Position” and an “End Vertical Position” with sliders be sufficient? With Expressions handling the animation at a velocity that is based on duration?

  Philip. Bowser
• 

  Michael Stark

  January 10, 2014 at 4:46 am

  See, that’s what I did with another slider.

  I’m just trying to avoid having to go into the position or keyframing the time.

  So the vertical slider is good to go. I guess what I’m trying to do is tell the second vertical slider’s second keyframe to snap to the keyframed “frame number” of the other slider.

  That way they both happen at the same time. The reason they both aren’t controlled by the same slider is that the vertical position needs to be independent.

  So just to reiterate. I’m trying to have “slider 1” control the vertical position and “slider 2” control the frame number the second keyframe in “slider 1” will land on.

  But also, I was trying to have “slider 2” min/max range always be the range of the current composition; or the min be 0 and the max be the last frame of the current comp.

  lol, i apologize if I’m making no sense and asking for a lot. I tried searching all day and tried Frankensteining together many expressions but nothing worked.

  I appreciate the help! 😀
• 

  Philip Bowser

  January 17, 2014 at 3:38 am

  Hey Michael,

  I’m still not sure I understand what your end result will actually be. It seems as though this is maybe not the best way to go about it. If you could maybe talk more generally about what you are trying to achieve, not specifically using expressions, but overall what your issue is and why an expression would help you, you may get an even better solution than this one you are trying to put together.

  Philip. Bowser

Reply to this Discussion! Login or Sign Up