[Ben Rollason]

Okay… I’ve got a comp 860×484… don’t know why that size, but anyway.

In the middle is a blue solid 200×200, which sits at [430, 242].

On to this solid (which is a 3D layer) I set position to…

origTY = 242; // orig (central) y position.
tMaxHeight = 200; //max y movement above or below origTY
tDepth = tMaxHeight*3; //you can make this more than max height to exagerrate the depth. At 1, the object will describe a circle.

tY = transform.position[1];
tY = (tY > origTY + tMaxHeight?origTY + tMaxHeight: (tY < origTY - tMaxHeight? origTY - tMaxHeight: tY)); //clamp tY so it can't move outside its upper or lower bounds. acosY = Math.acos((tY-242)/tMaxHeight); tZ = Math.sin(acosY); [transform.position[0], tY,(-tZ*tDepth)+tDepth];

and orientation to...

origTY = 242; //orig (central) y position
tFactor = 1.5; //adjust for more or less rotation
xRot = transform.position[2]/10;
[-tFactor * xRot * (((transform.position[1] > origTY)*2)-1), transform.orientation[1], transform.orientation[2]]


I think that gives you something like you're after. The trigonometry causes the solid to move back in space in a circular fashion. It's essentially describing a circle with a central point tMaxHeight behind your solid. The movement is driven by animating the y position.

The rotation is arbitrary, based on the movement back in z space.

Hope that helps,

-Ben.

http://www.benrollason.com

[Ben Rollason]

Hmmm. I posted the expression in the box, but it didn’t come up, so here it is again…

-Ben.


p1 = thisComp.layer(1).position;
p2 = thisComp.layer(2).position;
p3 = thisComp.layer(3).position;

tpoints = [p1, p2,p3];

tduration = 300; //frames

tFrame = time/thisComp.frameDuration;

tSector = Math.ceil((tFrame) / (tduration/3));

tSector = (tSector < 1?1:(tSector>3?3:tSector));

tBetween = [tSector % 3,tSector -1];

tStage = tFrame % 100;

tP = (tpoints[tBetween[0]]*tStage+ tpoints[tBetween[1]]*(100-tStage))/100;

if (tFrame > tduration) { tP = p1 };

http://www.benrollason.com

[Ben Rollason]

The following draws a triangle between the three points defined by three layers. They could equally well be points that you have inputed manually.

The rounded corner thing is tricky. Either the math gets really complicated. You’d need to have a point moving distant from your original point, but perpendicular to it. At each vertex, you would pause the initial movement for a time and instead animate the point in the arc of a circle around the vertex.

How long that time is depends on the relative length of the sides of the triangle to the arcs of the circles.

Like I said, complicated.

Couldn’t you just get the damn thing to follow a spline path? 🙂

-Ben.

http://www.benrollason.com

[Ben Rollason]

random(1) > 0.5;

will give you a 0 or a 1 randomly on each new frame. If you want more control, try:

tSpeed = 1;
noise(time*tSpeed) > 0;

and then adjust the speed variable to make it go faster or slower.

– Ben.

http://www.benrollason.com

[Ben Rollason]

Graham,

If I understand you correctly, it is basically an expressions job – a copy and paste one, but it needn’t be as cumbersome as you think.

If you make sure that the layers are in the same order between comps, then you could use something like this…

position expression: comp(“comp I link to”).layer(thisLayer.index).transform.position;

orientation expression: comp(“comp I link to”).layer(thisLayer.index).transform.orientation;

Type this in for one layer, then highlight the position and orientation properties, copy. Highlight all other layers, paste.

Now open up the other comps you need to link, select all layers, paste.

Voila. Linked.

Ben.
https://www.benrollason.com

http://www.benrollason.com

[Ben Rollason]

Thanks Dan!

http://www.benrollason.com

[Ben Rollason]

Lots of reasons really. I use it all the time in After Effects.

Specifically, this time I wanted to write a function that automatically picked up the first and last keyframe of one property and apply an identically shaped curve to different properties – that might have a different interval or duration.

It’s also dead useful for position averaging, anticipation or custom look-ahead type functions…

B.

http://www.benrollason.com

[Ben Rollason]

It’s easy when you know how!

Thanks Adam.

– Ben.

http://www.benrollason.com

[Ben Rollason]

Hi again Lennart,

Can you tell me where I can find the point cache tag. I only have 3 Clothilde tags and I can’t seem to find point cache anywhere else in Cinema (v10)

Best,

Ben.

http://www.benrollason.com

[Ben Rollason]

Hi Lennart,

That’s a new one on me! Thanks for the tip, I’ll give it a go.

Ben.

http://www.benrollason.com