So i got this project, it has 2 binary stars that will come into screen slowly, then start to orbit eachother and eventually collide... thing is, if I mask the path, the animation will be at the same speed throughout. Thats when i copy the mask shape and paste it to the position of the star.
My question is, is there an expression or a way to control the speed of the stars along a mask path? Or is it a matter of adjusting keyframes? because that is rather time consuming.
Usually is by pre-composing and enabling time remap. But it will be almost the same as creating keyframes at times and giving them influence. Its easier because with time remmap you can just say "I want the two-second mark's position now" by creating a keyframe and typing 02;00.
Precomposing as Cassius mentions is a great option.
I also sometimes use an expression to give me progress along the motion path. Add a Slider Control effect to your layer, and rename it "Progress". Then Alt+click the stopwatch and paste the following expression: