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Zak Parrish: Greetings and welcome back. In this video, I want to give you
a high-level overview of Cascade. I am not going to go over every single button,
knob, switch, and dial. If you want do want that, I recommend you check out
our documentation on the Cascade particle editor. This does
go over each an every button, and tells you what all the things do.
Definitely check out the documentation if you are curious. My goal here is to
give you a high-level run down, so you generally know what you are looking at
and where to find the things you need. At the top, you have a menu bar.
Given the options available in the toolbar,
you are probably never going to use the menu bar. We will move on to the toolbar.
I will go over the toolbar from left to right. You have some Save functions.
You have Restart Sim, which will either restart the simulation here or in the levels.
If you make changes and you don't notice those changes update in your levels, make
sure you click Restart Level. There are Undo and Redo buttons. You can click Thumbnail
to save the thumbnail. You can also show a few different things that
are very useful. You can see the bounds of the particle system by clicking Bounds.
This is very useful, particularly with GPU particle systems, because it is very
difficult to control when GPU particles render if you don't have a fixed set of bounds.
That is something we will talk about a little bit later when you create a
GPU particle system. For now, it is important to know you
can turn bounds on and off. You can show and hide the origin axis
for the effect by clicking Origin Axis. You can change the background color
by clicking Background Color. Not all particle systems look great
against black. In fact, the smoke here looks weird. If we start
increasing the background color Value, the effect becomes more apparent.
Be sure to play with Background Color to get the right overall feel of your particle system.
Next to this, we have the LOD section. I am not going to go into all of this
right now because I would like to have a separate discussion about what LODs are
and how to work with them inside of Cascade.
This is where you can go to create different levels of detail or LODs.
In brief, LODs are just different
tiers of settings based on how far
you are from the particle system. The farther away you get, the more
basic the particle system can become. Down from here,
we have the Viewport, which is pretty straightforward. The Viewport is a place for
you to preview your particle system. It navigates like all of the
3D viewports inside of UE4. You can hold down Alt and tumble around your
particle system with the Left Mouse Button (LMB). You can drive with the LMB.
You can use LMB+RMB together to track. You can use the RMB to rotate.
You have a View menu to turn on and off various things you might want to see.
Ones of note are Particle Counts, which are currently
on at the moment; and Particle Memory, which shows you how much memory
this particle system would take. You can also show and hide different things like
Vector Fields, if you are dealing with a GPU particle system.
You can preview what this particle system would like in motion by selecting
Motion. The particle system is actually moving around in a circle.
Deselect Motion. Moving on from there, we have the
Time menu. I find the most important thing in here is the ability to
turn on and off Realtime as you need.
To the right, we have the Emitter List.
This shows all of the different emitters that make up
our particle system. In this case, we have a lot. We have a couple
called Flames. We have Smoke, Embers, Sparks, and
heat shimmer for Distortion. Keep in mind when
working with these emitters, you have a lot of options. You can
right-click on any emitter. Under the Emitter submenu, you can:
Delete Emitter, Export Emitter into another particle system if you have
two (2) instances of Cascade open, Duplicate Emitter, or
Duplicate and Share Emitter. If I select that for instance on the Flames emitter,
we get another copy of this emitter and all of the modules
are completely shared. If I change one, it is the same as changing the other.
Since we don't need that emitter, I am going to right-click and select Delete Emitter.
It is going to pop up a warning and say,
"Are you sure you want to delete it?" Click Yes; we want that gone.
One thing I want to mention that is very important
because it is not the most discoverable, is there are some
settings which are inherent to an emitter itself.
I want to make quick mention of the Details panel. There are several Details panels
in UE4 and hopefully, you have been exposed to them at this point.
The Details panel is where you change your properties.
You might notice as you click on different modules, your Details panel is
context sensitive and will change for the details you see. If you click on an emitter,
you will see the settings for that emitter. If you click on a blank spot
in the Emitter List, you get the properties for the entire
particle system. That is a huge help and a major trick.
It is not exactly a secret, but it is one of those things
that I want to make sure everybody discovers. Keep in mind,
if you click on a blank spot in the Emitter List like this empty area
on the right-hand side, that gives you the properties for the entire particle system.
Along with the emitters, there are some things you should know about.
You have the ability to turn any emitter on and off
with the checkbox. You can enable Solo Mode on an emitter to see only
that emitter by clicking the S icon. You also control how it renders.
Click the S icon to go into Solo Mode so it is easier to see.
By clicking this rendering icon, I converted over to
points, or to crosses, or to
lights, or I can nullify it all together. There are some controls there
for how you see different things. Solo Mode is probably one of my
favorite things when setting up an effect. If you want to make sure that your
fire looks exactly right, you can enable Solo Mode and perfect it.
Then, you start bringing in other effects as you need them. The Details panel
is like every other Details panel in UE4.
The search bar is of particular importance because you can use that to find
a particular property. Sometimes these property lists get pretty long. Also, if you
are trying to figure out what you changed that made a
particle system look bad, good, or if you wondered "how did I do that?",
remember you can click on the Eye drop down menu and select
Show Only Modified Properties. Also keep in mind, you will need to turn
that back off if it suddenly looks like you are missing some properties.
In the lower right-hand corner is the Curve Editor.
The Curve Editor is massive and important. I can't stress
enough how vital it is. Real quick, I am going to
remove all the curves from the Curve Editor by clicking the RMB
and selecting Remove All Curves. Click Yes. Now, it is completely empty.
Let's some curves to the Curve Editor. Enable Solo Mode
on the Flames. We have a Color Over Life module.
I can send any curves associated with this module
down to the Curve Editor by clicking on this tiny green
curve button on the right-hand side of the module. Click on that. There you go.
We can't see the entire curve. We can click the buttons
to fit horizontally and vertically (Horizontal and Vertical).
Now we can see the curves and how great they look.
Let's hide the Alpha curve because we don't necessarily need to see that.
Here are the curves for Red, Green, and Blue.
Press Shift and click on one (1) of the
curves. CTRL + click on one (1) of the curves.
I will create a color by arbitrarily moving the
curves around. You will notice now the fire
is changing color mid-way through its life. That is certainly not the best
color I could have possibly chosen. Let's choose something that is
a little more red dominant. Select only the Red,
and drive red up. Then, select only Blue. You will notice I am
clicking on the squares for the Red, Green, and Blue to turn those on and off.
For Green, we can use a little bit of green because it will
start to give us a bit of a yellowish tint. For Blue
if we turn it up, you see we are starting to get a little shade of purple.
If I pull Blue back down, that pulls blue out.
Now, we are just getting a little bit of yellow frame right in the middle. You can see how
those curves control the behavior of your objects.
If you don't want to control this manually and
you prefer to punch in numbers, you can select Color Over Life.
Here is Color Over Life in the Details panel. Its Distribution is a
Constant Curve, which makes sense because we were just editing the curves for it.
Expand the Points in that curve. There are three (3) of them.
The point in the middle is about 20 x 3.5 x 0.12.
We can set those manually. We can set X to 20. X is red in this case.
Change Y to 3.0 and Z to 0.2.
Whichever way you want to control those is fine. You will notice it did update the values
on the curve as well. You have a lot of controls
over how the Curve Editor works. You have Pan mode, which is
going to allow you move the view around like you are panning as you
drag with the LMB. Zoom mode allows you to zoom in and out.
LMB will zoom you vertically. RMB will zoom you horizontally.
All you are doing really is changing the extents of the graph.
Then, you have the different curve types you might need.
Hopefully you are familiar with these. You can click Auto if you want a
spline sort of curve. You can click Linear if you want a straight linear relationship.
Click Constant if you want something to change the moment that
key is actually pressed. You can play with the tangents (Flatten and Straighten).
You can also put curves into tabs as you need.
Create a tab by clicking Create Tab. Call this
"MyColorTab". I can add curves
into the Curve Editor, like these curves here. At any point,
I could go back to the default tab. Click the Current Tab drop down and select Default.
Let's empty the Default tab. Right-click and select Remove All Curves.
A warning will pop up saying, "Are you sure you want to 'Remove All Curves'?" Click Yes.
Go back to MyColorTab. It removed the curves from MyColorTab as well.
Select the Curves icon on Color Over Life to add the curves.
Click the Current Tab drop down menu and select Default.
You can see the different between the tabs. The Default tab has nothing in it.
MyColorTab has the color curves. It is a way to keep your
curves organized if you want to be able to quickly switch between them.
That is Cascade at a glance.
I didn't want to spend all day going over each and
every single button because you are going to get familiar with Cascade
as you use it. That is one of my goals. I want to push you through some particle
effects and make you do some things. That is going to wrap things up for this video.
Thanks a lot. ♪♪♪
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