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In this screencast we are going to show how to
effectively use the slider option for repeating
“increasing once”. So what is that?
That is an option where the animation will go from
t-=0 to the endpoint exactly once. But there are a
few things to consider.
First let us see what we want. Let us say that
we want the man to walk from 0 to 4 or
whatever the distance d is.
So let us put a picture of a man. Insert image. This
is one little tiny tip. If we come down here, both
points P and A glow.
So we can either move t over to get P by itself or
we can click over here in the Algebra view to get
P by itself. Okay.
There is my man image. Insert. Now if we turn the
animation on the man goes with the point P.
Now what happens if we change the animation
to be the repeat “increasing once”?
Right-click, go down to object properties, on the
slider tab, we see the repeat and we will change
it to “increasing once”.
Now that sounds great. Let us turn it on. What
happens? The man goes to the endpoint and then
the play button is no longer there.
Okay. Then you have to right-click and all this
other stuff to get it to animate again. So how do
we fix this so that it works really great?
We will insert a button that says “Animate”. So
animate is our button name.
Now the first thing we want to do is reset - this
is script, but it is nothing difficult. Reset our slider
to 0 so t=0.
And then hit Enter and then we say
startanimation (all one word) and then it is best if
we put the variable in there.
So bracket, then “t”, then close bracket. That is it.
t=0 and startanimation. Apply. Let us get our Move
tool and try it.
Animate. Now we can pause it down here and
then restart down here, but will go exactly once
and if we want it to start it again, we can start it
again with the Animate button.
Now another thing that is nice – remember in the
last video we showed that if we right-click on d
and we say “scripting” and we told it t=0.
Probably the best thing would be to have it stop
the animation first. So we go to the front. Hit
enter.
BTW there is no stopanimation command. But we
type startanimation and we tell it [false] and that
is actually “stop animation”.
So startanimation[false] and then t=0 so it resets
it. Now don’t forget to do this. You must come
down here and find OK and then click Close.
Now if our animation is on and we change the
value of d, it will reset and stop and wait for us to
animate again.
Here is another example of a worksheet where
the animation on the slider t is “increasing once”.
It has a variable length - the length of this arc.
The animation button rolls out the arc and on the
radius, the angle and the reset button is the
simple scripting: startanimation[false] and t=0.
So I can reset here and look at it before rolling it
out again. If I start to roll out and I change the
angle.
Notice the animation stopped and t=0 again. And
then roll out again. If I change the radius, again it
stops and resets.
So on all 3 of these we have that scripting
startanimation[false], t=0 and on the slider itself
we have used the repeat “increasing once”.