- [Instructor] In this lesson, lets finish up the shape
of the aurora and give it some nice colors, shall we?
One thing I've never mentioned in this course,
you can of course select several Frames
and frame all of them together with a bigger frame.
I am not sure I like it, feels kinda, chaotic.
But you can definitely do it, if you want,
and call it a Shape frame.
And now, we will multiply a few nodes over this shape,
to cut off those ugly edges.
For the top down cutoff,
we can actually use the same gradient
that we built originally.
Lets just grab these nodes here, duplicate them,
and put them all the way back here.
Reset your Ramp points, and also add in a Mix RGB node
set to Multiply.
Connect the Ramp and the second socket of Multiply node
and raise the Factor all the way to one.
And yeah, that's the other side that's cut off, right?
So, as I said, flip these two points,
which basically inverts the gradient,
and now its working as we want it.
Okay, frame this for example as falloff.
and the final step we'll do
is to fade these edges as well.
In fact, we'll do it by using another Gradient texture,
but this time, we'll make a Spherical type,
which has this nice falloff on the edges.
Now, our goal is to get it in the middle of our object,
so that the fading happens only on the edges here.
For me, these values worked fine,
with X at negative 0.8,
Z at negative 0.5,
1.6 on the X scale and negative 0.4 on the Y scale.
I also increased the contrast by pushing the black point.
Then, when you multiply the result over the first gradient,
it cuts off our aurora on the sides,
which is what we wanted.
Now of course we still need to finish up the colors.
So on our reference, you can see that auroras
come in many colors and shades, however,
one type I do like and that will probably fit nicely
to our scene, is this one,
where the lights start green at the bottom
and gradually get more bluish, with a touch of magenta.
So let's try to achieve that,
by first adding a new Color Ramp.
When you plug it into the color,
your aurora will turn black and white,
but that's just because there are no colors here.
So change it to this seafoam shade,
and the other side to cyan.
Nothing's happening though.
So, lets instead Ctrl + Shift Click preview the node,
to see the placement better.
To achieve the type of gradient we want with this
just add these Mapping and Coordinate nodes,
plug the generator type in,
scale Z value to 4,
and rotate this value 90 degrees.
What you want again is this top to bottom
transition of the colors.
And of course, nothing is stopping you
from playing with these points,
adding a new one and making it magenta or almost pink
and fiddling with the positioning of the stops.
But that is ultimately up to you.
So at this point, I am quite happy with this.
So let me frame this Color part,
and save my file,
and then append this object to my scene.
And after putting it at its place and scaling it up,
you will probably realize that the Emission
is now much more intense due to the larger size of the mesh.
So, that's why we have this Multiply node here,
now because just as you could easily make it more intense,
you can now go lower with the number,
and that will solve the problem.
Also, you can always jump here and keyframe the W value
on your 4D Noise textures,
that will make the shapes move.
Oh, and don't forget to select
your newly created keyframes
and in the graph editor or timeline,
hit T and make them linear.
Nice!
So this way, you can add this effect to your scenes.
In the next lesson, we'll tie the whole thing together
and prepare it for rendering.
(suspenseful music)