Localized cloud Y animation parameter difference-problem

Started by Kadri, August 30, 2014, 12:53:16 pm

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* Make a localized 3D cloud layer.

* Animate the cloud layer to different Y highs with the "Centre" settings say from frame 1 to 10

In the animation panel of the cloud you will see the right Y settings from frame 1 to 10.

But what really happens is whatever parameter you had in the "Cloud altitude" will override the "Center" Y value. Animated or not.

This frustrated me yesterday because i had 4 cloud layers animated and
all looked right in the animation panel but it didn't worked right as i thought it should be.

Basically to use the Y value for localized clouds you have to use the "Cloud altitude" settings.

When you hold the time bar and want to go thru the frames you see the strange behavior of the
cloud in the Y value as it jumps from the animated parameter in the "localized" Y but
sits in the end where the "Cloud altitude" Y setting is.


I don't think the localized parameters should be used to animate clouds, or did you want to lower the cloud in time? It's just the area where clouds occur.
If you want to lower clouds, I would animate the Y of the fractal and if no or a little movement of clouds is necessary, also use a distribution shader with an identical animated height restriction. But the localization should be bigger than the area you want to traverse with the cloud. Localized is a sphere, more or less, you can also use a soft SSS, which is a vertical cylinder. Theory, never done this.


You know you can do many things differently in Terragen.
That is not the reason that i am posting this here Ulco.
The problem here is that Terragen shows parameters and renders differently...confusing even wrong if you ask to me.
What you said could be done of course.
But unnecessarily harder and for what is the localized cloud option for if you have to use different ways to localize the clouds? 
When you tick the "move textures with cloud" option all the textures should move with the cloud already.

"I don't think the localized parameters should be used to animate clouds" Why?
You could use it for many different things probably.

My reason was to change the radius, high(of the cloud layer) X, Z and the Y position in time.
4 different clouds at the same time with different values.
The easiest way is to use the localized part for this.
Still is, if you are careful of the problem and use "Cloud altitude" for Y.


I can see how this would be surprising, and it might be something we can improve in future. But can you achieve the animation you want by animating the cloud altitude parameter, and making sure the cloud centre Y coordinate is not animated?

Just because milk is white doesn't mean that clouds are made of milk.


As i said if you use the "Cloud altitude" to animate (without animation too of course) the Y value takes
over the localized Centre Y setting whatever the value there may be.
So at least for my own animation i had no problem using it this way.
I just wanted to point it out that it could be confusing if someone
tried it with the Localized options only like i tried at the beginning.

By the way the two values there doesn't match fully (when animated?).
When you use 5 in one the other can be 4.999988 or whatever.
That wasn't a problem for me. Just saying for your information.
Thanks Matt.


Good to know there is a workaround but I understand the confusion.

About the differences between Y and altitude, that's probably because of planet curvature. Away from the origin, Y is not the same as altitude. Also, because some calculation has to happen to convert between Y and altitude, even at the origin it's possible for some rounding error occur, resulting in very small differences.

Just because milk is white doesn't mean that clouds are made of milk.