>>Hello. Welcome to
Unreal Archviz Webinar series number 3, so welcome. We are going to talk
about lighting today. Before we begin,
a couple of questions. I hope if, Chris,
you can set the polls — have you used UE 4 before? Great to know
if you are a beginner. And have you seen
the previous webinar, because I am going
to go over some things we have talked about before. If you have, it will just be
a quick reminder. Otherwise, I will explain
a little bit more for those who were not there.
Great. So let us crack on. Today we are going
to look at two scenes. I have done one in the interior,
like this one, so we have got an overcast sort
of scenario with soft lighting. Soft lighting, soft Shadows, and this kind of very easy
to set up. Then we will look
at the same scene lit with artificial lighting. So we have just here
a range of Spotlights, IES lights, a little Omni
for that little lamp there, with a lampshade,
some surface lampshade. Then we have got
a couple of spots and some Area Lights
for the back of the shelves, and then some big Area Lights
that I put up; some big
self-illuminating spheres that I put up in the staircase. So we will have a look
at how I have set that up. Then just that scene that some
of you might have seen already, which is a great example
of a daylight exterior, sunny day setup.
I will take you through that. Then this exterior [INAUDIBLE], but lit by night
from photo references that I found on the internet. It was really exciting
to work like this. So I will take you through that. Okay, so quickly,
another question, do you already know
about deferred rendering? I talked about it last time,
and it is a way to go into the comparison
of VRay and Unreal. So if we come back
with the polls for that, it would be great, so that I know
if you already know about this. Anyway, I will carry on. Here we have just got typical
VRay render, and we have got this
lovely soft light happening, and this we all know about. What this VRay is,
is a forward-rendering, so the camera shoots out a ray and sees what is happening
when it hits geometry, and then renders of the pixels,
more or less, as far as I can understand,
that is my understanding of it. Maybe not completely
scientifically-based. But here, what we are trying
to do is understand a little bit
about how Unreal works. This is showing the way
this deferred rendering happens, again as far as I understand,
this is showing how we effectively have
the different renderers working on top of each other
like layers. Where is my little diagram here? Yes, so I am just going
to move that one up here. Here we have got layers
of different renderers stacked on top of each other, contributing to
the final pixel color. That is what we have
got in the end, is our rendered image, but made up of all
of these different things that we are controlling. Here we have got our outputs
that we are fairly familiar with, like the Zed-depth
and the Ambient Occlusion here, but there are many
that work internally, and that is kind of
a little bit beyond me. But it is really interesting
to understand how this works, because when we set up
the different Components that make up
our final pixel, it is useful to begin
to think that way, rather than the way that we are
used to working with VRay. So Skylight here, it takes up HDRIs
and Cubemaps and everything. I have put Cube here, especially because that is
what I am going to show you to work with,
very, very simply. We have got the Environment,
the Atmospherics; we went over this last time. I need to go over it again,
but the direct light, for those who do not know,
is going to be the sunlight. We have got some examples
working with that, and the Lightmass. Where we have the dreaded
Build button and the Build times
that go through the roof. We will try to see a few tips
how we can deal with that. Basically, this is
the Global Illumination, the GI, the light
bouncing around that Unreal calculates for us. Then we have got
our Reflection probe. Again, we spoke
about that last time, and we have got different ways
of generating Reflections, and those are very quick
and useful, but they are not very precise. We have got
Screen Space Reflections, and Planar Reflections
to work with instead. What complement lighting — so what we have got in parallel
of lighting is the Post-Process, so it really would not be wise
to talk about lighting without talking
about Post-Process, because in Unreal,
they are both interlinked, and there is a sense —
they work together because they are part
of the same package, whereas lighting is, in the traditional offline
rendering workflow, the lighting happens in 3ds Max
rendered in VRay, and the Post-Process is done
in Photoshop or After Effects. We do not really want
to go back to modify lighting after we have rendered
and done the Post-Process in another package. So traditionally, there is a
cutoff between each of these, and we will not get much chance
to revisit the lighting. Well, if we really have to,
obviously, but we are going to make
a few unhappy people. So this is different. I am going to explain
a little bit what is, for me, essential in
the Post-Process, which, as you can see here,
it is HDRI Tone mapping. The reason why that is,
first of all, I would like to poll
this question: How many people,
have you used VRay? Are you a VRay user,
regardless of Unreal Engine, because if you are, I would like
to address some concepts that we are familiar with,
which are this stuff. It is SRGB, Gamma 2.2
Linear Workflow Color Mapping, blah blah blah, exponential,
Rinehart, all this stuff. We are the ones who are
familiar with the Gamma; this is that, because blue line
is what happens inside, the software inside of the
computer, everything is linear. But the response, in this case, the response of this very,
very old, now defunct monitor, the curve was more of this
light blue one, the 2.2 curve. That was integrated
into the rendering, and then we have got ways
to clip the highlights which are exponential,
and so on. We have got the Gamma 2.2, the calibration
with our Texture maps. It all gets very complicated. On top that here, we have got
the environment colors that contribute to the pixel
being handled by 3ds Max, and then by VRay.
This button as [INAUDIBLE] as an option too.
It is all very complicated, and it is all for us to cater
for a technology that is no more.
It works, for sure; it is just a way to
effectively light our Shadows. But something has happened
under the hood that I thought
is worth mentioning, because I did not know about it until I found out
through this Tone Mapper. What happened is that
in the film industry, they obviously have
the same problem. They have been working on it. The Academy, I think
this is the Oscar Academy has been working on it. They have come up with
a standard so that people, I guess different studios can
communicate and exchange files, because since rarely one studio
works on the same movie any more these days,
so they needed to get something that is going to work
for everybody. So they came up with this. It is already
a couple of years old. From what I understand
has been in Unreal Engine for a couple of years,
but under the hood. It has been enabled, by default,
since version 4.15. As usual, it is great,
because a lot of the times when Epic do an update
on Unreal Engine, it means that we have
to do nothing. So this is why you really
do not have to do anything. It all works
without you doing anything. However, I am just going to
explain to you what this is — Slope, Toe, Shoulder — I had no idea
what that was when I saw it. So this is what that is:
That curve, that Gamma curve, has become our S-curve
that we would probably use if we were doing
color correction in Photoshop, especially to color —
to change contrast, and things like that.
That is what that does. The slope is that black line,
the angle of that black line. The toe is that here, so how tangent
to the horizontal it will be, and shoulder is the upper
[INAUDIBLE]. The white clip
and the black clip are things we are very familiar; if you have used Levels
in Photoshop, and that is it. That is really, really simple. The effect of that
is that Tone Mapping has changed between version
4.15 — now this is VRay. When you were to increase
the Intensity of a Spotlight to unreasonable levels;
very, very high, which is kind of extending
the range and challenging
the Tone Mapper. But this is what happens
in reality, obviously the sunlight being
the brightest of all things, and light behaves
in a certain way, and so on. Here, it is
this blue colored spot, increased to unreasonable
high intensities, so it became even more blue, it is just tending a little bit
to the purple there, but really just became
massively more blue. Here, on the other hand,
in Unreal Engine, when this is increased
very, very high, you will notice that the color
changes over to white, and becomes burnt out,
completely burnt out. But as opposed to all
the problems we had, we are using
linear in 3ds Max, while rendering, the burnout
spot is very tight here. There is a beautiful gradient,
going from white to the blue, obviously here, also,
due to the square falloff. So what I have done
is just taking a picture of this LED here, and you can see that
what happens in the photo is that at the brightest point, that has actually gone white
as well, completely burnt out. Then the rest is beautifully
kind of gradated and depicted. So Unreal is now able
to represent this effect
much more accurately. So the other thing to mention,
though, is that I did not
see this with my eyes. With my eyes, I saw something
not quite like that, but that was still red.
Interesting. But this looks
more photographic. Other thing to mention
in the Post-Process Volume is definitely the white balance.
This was the original shot without the white balance
applied. I just lowered the temperature
here, which now enabled me to have a lot more of a play
with the cool, because this obviously
being covered in all wood, it is very warm in color.
Then I added this — the reference had
this concrete floor, which was rather cool.
It allowed me to turn that down and bring the coolness
back out into the floor, whereas here everything is warm, and it is a bit sort of
like a sepia-color, tinted. LUT — I am going to refer you back
to the documentation for that, because it is explained
very well. I did not actually use it
in that scene, so I cannot show you
the demonstration. But maybe I will see
if I can do a speed-up demo, and put that on in here. Let us see, let us crack on, because we have much
to go through. Here, the layers, the LUT, yes.
The Vignette is simple and easy. It is always great
to add the Vignette, I think. You just see that here; those edges of the scene
look very bright. They sort of do not really
tell much of a story. So with the Vignette,
enables to tone them down and to bring the focus back onto the sort of focus
area of your — you have chosen usually away
from the edges, I guess. So that is really simple
and easy, and quick to do. The Exposure — I need to show
you this in the interface; let me just — right. I will show you about the
Exposure in the interface here. Give ourselves
a little bit of room — it is a little bit complicated, because there is
all these things; Min Brightness, Max Brightness,
blah blah blah, Exposure Bias,
and all these things, which I am going to go into
in a minute. But the first thing
I would like to point out to you is that if you click on this
Lit button and you go down to Exposure, you have the ability
to fix at Log 0. I have taken the habit to set
my Intensity of my Skylight at this setting of 0 here, so that I have some way
of knowing where we are, because what happens with this Exposure from
the Post-Process setting is that it is going to —
obviously it does not work here because I am on 0.0 here,
but it is the Exposure here is going
to vary up and down. You might set the Exposure, and you think it is right
when you are here. Let me just show you —
I bring it back to automatic. See, we were kind of all
right here. We will set the
Exposure Bias to -1.2. Then here, it is kind of just
a bit too dark, really. Here we wanted to be up here,
so nearly at 0.0. That becomes
a little bit annoying. Then also, what I do
is this speed up and speed down, I whack it up
to whatever maximum, so that you do not have
to wait for ages, so that you know exactly
what is going on. Here it is over-bright.
Either you make the whole thing so that the Exposure
is not going to change, and that sort of works, usually
that is what we are used to when we do fly-throughs in VRay, because the Exposure does not
normally change unless we tell it to. Or what is a little bit
more complicated here is to use this
Brightness mix, a Min and Max. In this case, they recommend have
the Min Brightness near 0.0, so we can have it at what
the recommended level is, and I guess that will
probably work in most places. In this particular interior,
it needs to be quite high. I will set it at 1.2 here, so it will never go brighter
than that, even if we are in some very,
very dark places. That is what is good
to understand. I think this Maximum Brightness
needs to be changed much less often, that is kind of to deal
with the same affair, but with our darkest spots,
so how dark the darkest will go. It does not seem
to need tweaking much. That is for the Exposure. But I think it is quite
important to point this out; I went for ages without
knowing about this feature here, Exposure fixed at Log 0.0,
so it has been, I think, cooler, in the Forums
recommended to point them all — put them both at the same value. Say if they are both at 1.0,
that kind of works all right. But if we put them
all at another value, then we need to change
the Exposure Bias to get back
to something acceptable, and then it is all very
complicated, and a bit contorted,
then might be unpredictable. I just tried to keep it
simple like this. Work, so I will say it one
last time, fixed at Log 0.0. Then once it is more
or less within range, I just go back to my
Post-Process Volume and just tweak the Exposure
on and up, and work with this Min
and Max Brightness to adjust it. But at least I am not way off. I hope that makes sense. Maybe I will just leave it
at this for now, and let us go back
to our next slide. This is the slide
I put together. Let us have this little
walkthrough of how I go from — basically how I set up
that scene all together. I show you from the start
how to create a really, really simple, easy Cubemap. The reason why, HDRs are very,
obviously, superb, great, but I wonder whether
Unreal deals with them absolutely in a perfect way. I have had a bit
of strange things happen that were not that predictable. This is a really simple way
and really easy to have a very flat color, like an overcast day,
to light your scene. It is extremely predictable
lighting from all sides, and gives us a nice
environment color to work for. It is a little bit like having
the color for the environment, in the environments
locked in Max or in VRay. That is really easy. It is
the sort of basic GI setup. I show you the walkthrough,
and then I must admit, I have kind of put this sequence
of events after I have done the video, so some of it
does not quite match, but it makes more sense
as a good workflow. I will keep referring
to that in the video. Let us just crack on. This is me playing the video. This is like the old PowerPoint,
but I thought we have not got this problem anymore,
of the video not playing. Right, nothing that a restart
will not fix. Here we go. I am creating in Photoshop
this Cubemap. Feel free to fire up Photoshop
and go along with me on this. This is me doing it,
but I have sped it up, so it might be
a bit quicker than you — but while your Photoshop
is starting up, if you are in front of your
computer, feel free to do it, because then you will have
a Cubemap ready to go to use
in your own project, as soon as this webinar
is finished. I just created a square image,
1024 pixels, or 256 will do, actually, I do not know
why I did it so big. I just resize it,
scale it 600 times, 600 percent. We want this image
that we have in this — an image that comes
in this webpage exactly, which is telling you
how to create Cubemaps. This is, obviously, in order
to output them from Max, back in the days
when you needed Cubemaps. Here, what you do is you get all
these numbers from the webpage, and then you save it as .dds,
from Photoshop. This is how to create a Cubemap, and you make sure
this is on the Cubemap. No need to bother about Mipmaps. This works like this.
Then save it as .dds. Basically here, I have taken you
into the interface, and I am building up
just really — just bringing in some geometry into a new Level
that I have created, to show you how I set up
that Cubemap into the Skylight. I am just bringing a Skylight,
make that bringing that — I have just imported the Cubemap
that we have just made, all there, all good. I have just stuck it in there in
the image slot of the Skylight. Now I have set up my Skylight,
now I have set up — I am looking at the Lightmaps, so just making sure that it is
all the right resolution. Because as you know,
when they come in, those squares are really big. I make them really tight
so that they are red in color, so you can press
on your keyboard ALT-0. ALT and 0 give you
this Lightmap Density view, and you can access it through
this button as well, of course. Once we have got the Lightmaps,
I will just put here, because I am just going
to Lightmap settings, so Lightmass portals. I add them afterwards,
because I forgot. We have got
our Lightmass Settings, and these are the ones I use, so I turned
the Environment Color to black, but do try it
with white as well, because it adds
to some of the dark areas, so it is very interesting. And the settings I use are 0.75
and 0.75 for Indirect Lighting, Smoothness
and Static Level Scale, and then number of Indirect
Lighting Bounces to 12.0, and Lighting Quality on 4.0. You can bump that up
to 10.0, 20.0, if you need,
for the final render. But when I am working, I either
leave it on 1.0 or 4.0, okay? Here I have put it onto —
you might not have seen, because I was going too quickly. But here, I turned
my Ambient Occlusion with a Post-Process Volume. I have set my Exposure on 0.0,
and I have got my Skylight. Just quickly here,
while we are rendering, I thought I would just show you, for those of you
who do not know it exists, this is the Swarm Agent
that Epic provides, which is the back burner, which is enables you to render
on lots of different machines. But also, when Unreal
renders the Lightmass, it throws it out of UE 4
into the Swarm Agent. That is why while
this is building lighting, you can still carry on working
and use the interface, which is brilliant. This is all handled
by a separate program called Swarm Agent, and the network rendering works
very, very well; it is really easy.
Once it is set up, it is great. But what I am wanting to show
you now is a way that you — when this comes by default — let us just take you
through the steps. You go into here, and most of
the time you will see that Show Developer menu —
how did you get to here? You go in your system tray here,
and you see that little S icon. You double-click on it,
and you get the Swarm Agent. Then when you go
into the settings, you see that the Show
Developer menu is set on False, so you set that on True,
like I have done here. Then you get your
Developer Settings tab. You will probably see
that your local job’s default process account is not set
on the number of processes you have in your machine. Mine, I have got eight calls
into this laptop, and it was set on 6. If that is the case, I have got
20 percent of my power which is not being used.
You just set this on 8, and you have just immediately
gained 20 percent power; therefore, 20 percent more time. That is just a little quick tip
that I will just remind you of when we talk
about the rendering time. Basically, you can see my CPU
level here has gone very high. Here, I have forgotten
the Lightmass portals, so I quickly add them —
no big deal. But I do recommend you use them,
because I have noticed that the quality of the light
calculation is much nicer, much better, with them,
and possibly quicker as well. When that is done,
I carry on the — yes, so here the Reflection probes,
you see how important it is. That back wall was really
completely washed out before I moved it, like this. Then I moved it, and that sort
of corrected that problem. Here I have not —
this is just a default standard super Material,
there is nothing to it, just one image
on the diffuse color. So there is something wrong
with the Reflection. But just to highlight the importance
of the Reflection probe. Here, I have just
come to the end, and I just backtrack
a little bit to show you
what I have rendered. The rendering time for this room
was 29 seconds, on sort of low-quality,
or Preview. Then the final one
that I have got in here only took 5 minutes,
production, and 4 here. It is really pretty satisfactory
lighting calculation and precision
for such a small render type. Yes, that is my
walkthrough here. I am going to go through
some of the settings again, just to make sure that is all. Let us just go through
the Lightmass, just to make sure
we are clear on that. Lightmass,
we go to World Settings, and these are the values
that I use. Here, it was not even on 12, 3,
it was on 12. When you set that to white,
it helps as well those dark areas. That is great,
it helps with the way the Skylight does not get too —
and yeah, so that is it for the Lightmass,
pretty simple. What you really want to do is
untick Compress Lightmaps here. You really do not want to add
some .jpg artifacts to your lighting,
bounced lighting calculations. Lightmass Settings, Lightmaps — again, you press
ALT-0 on your keyboard, so you can see that here
I have set them — here, the grid is really,
really small. I went possibly completely
overboard, because it is a very small room. It wanted to see
if it made a difference. But to be honest, it only took
five minutes to render, so it is not a problem. You can see how it comes in
by default; this grid is very, very large.
Maybe not that small, but the way
I like to describe it, the grid needs to be
as small as this — at least smaller than
the smallest item that you are going to have
in the scene here, being especially the feet
of chairs, and things like that. There is a bit of
LOD here on there. This is very, very important,
to give you the smooth Shadows, and also it massively increases
your render times. Here it is not a problem,
as I said, because it was only 5 minutes.
But if you have a large scene and these Lightmass Lightmap
resolutions are too high, then you really need to kind of
bring them down to a level that is going to be more coarse. I think the Lighting Quality
in Unreal, so far, has worked great. It probably could afford to be
a bit more optimized than this on this scene.
So far, so good. Carry on — Lightmaps.
Build time issues — obviously, we have got very high
render times on some scenes. Here —
you probably already know this, but I work on Preview,
when I just put in my — I have got my Skylight, and I just want
to see the general level of lighting in the room,
how to set this Intensity. I am probably going to have
a lot of iterations. I work on Preview,
then I put this down onto one. These are the only two settings that I tweak to change
to work quickly, and to reiterate
the lighting calculation, the Lighting Quality here,
and the Lighting Quality here. Obviously, if your scene
is taking far too long to render and you cannot handle it, then you are going to have to
change your Lightmap Density, bring that down. As I told you also, Swarm —
you get to Swarm by, if you cannot see it
in your system tray here, you need to set off a render. So you need to set off a render.
I am not going to do it now, but then your Swarm
will appear in here, and then you can do these
Mins I showed you. Obviously, then,
with Swarm you can add machines. I am not going to go into it now,
but it is a bit complicated; it took me quite a long time
to sort out to understand how. But it does work. Also, before a final —
you have got lighting info, Lighting Static Mesh info.
I get this little window. Lighting Build info,
and here there is nothing. But do have a look in here. It is a list
that looks a bit like this, and you can order it by the time it took
to calculate the lighting. You will see that
the ones at the top, sometimes some come out way,
way, way higher than the others. It is a very quick
and easy way to debug some items that really will need
optimizing and looking at. That is top tip here,
to use this lighting info, Lighting Status Mesh info, and look at the build times
for each Mesh. Let us go back
to the PowerPoint. Now I think I have
given you enough theory. Let us look at the scene. I just basically
took you through — in fact, let me try
and do it straight into — now, let us do it
in the pre-set ones, because it will be much easier. Here I have just started with
the scene completely dark, and I have just turned
the lights on one by one. This is a kind of a good screen
shot of the final lighting calculation with effectively the GI,
which we can see here, which is sort of turned down
really low. What we have here is effectively the resulting calculation
from the Skylight, but with the bounce light
turned off, or very, very low here.
The Shadow areas are very dark, but we see that we have got
really nice contact Shadows, and a really nice soft lighting coming from the diffuse
background color. That is my Skylight. That is the sort of settings
with my Cubemap in it, then here set up nearly 15. That is with
the Global Illumination turned back on, basically. We have got a really simple,
just one light. Then I have added
these Spotlights here. I will go in the Spotlights
in a minute, but here what is interesting is that I have turned off
my fixed Exposure. Now I have added
this directional light, which is a Skylight,
so the Intensity here is 25.0, and I have given it
a little warmth in the color. But you can see that
as I turn my Intensity way up, instead of nearly to 80,
now to one and a half thousand — the Tone Mapping
really reacts very, very well. This is where after
all this theory, we have got our nice
overcast day lighting, then we can add a sharp light
that comes from maybe that sort of sun
just poking through the clouds. Here there is more kind of
Mediterranean sun, hard sun coming in. Here is more of a science-fiction,
divine look, sort of God rays, somebody has
just seen inspiration. Yeah, this is effectively,
this is the kind of techniques I use to the light this scene. It was actually that divine sort
of light setup; high contrast. There was a lot of work here
done by the Tone Mapper to put
everything in range. But it really is something
we can use to create the level of contrast
and emotional message that we want to carry through. Moving on, interior at night —
that is the shot here. Like I said,
we have got Spotlights in here. Let me just fire up
the interface, the same project, and I will open
the one by night. It is just open straight away — I got all confused
as to what is what. Here, everything is off.
That is great. Okay, so what we will do, I am just going to show you using this thing,
or let us just — let me just have a quick — yes,
so you see, classic mistake — I have this
Exposure fixed at 0.0 from the previous,
from having this Level open. Now I have got this Level,
and I forgot, so I was, like, oh, what is going on?
Here it is a bit confusing. At this Level, I have got
four lights on the ceiling here. They are IES lights, so just to speak a little bit
about these Spotlights. The way the IES
worked for me is, I have to have this Attenuation
Radius completely out. Normally it comes — no, sorry,
the outer Cone Angle, because obviously if you
have got your cone like this, your IES is going to want
to display information up here. But the cone is going
to block it out. You need to have your cone
and go really way out. The IES I have just put in here,
so that is really straight-forward. You just import it,
straight in here. All these lights
I have set on Moveable, so they do not get
calculated into the Shadow. I do not know why
my second frame is gone here. But anyway, the lights in the
staircase are these spheres, which are just what
I call Area Lights, but really what they are
is with a Material, with a self-illuminated,
emissive color. I have called it
“Emissive Power,” which I can change in here.
That is set on 10.0. The Mesh itself must have the
Use Emissive for Static Lighting ticked in order
to be used as an Area Light. So same thing for these rectangles
of light at the back here. This is great,
because it is totally baked in, so you can have as many
as you want. It will have absolutely
nil effect on the performance
of your scene. You can have an unlimited
amount of lights here. Obviously, they are not dynamic. Here, the Spotlight,
what I have done — if I just put these values back, you can see that
it is quite a gamey, harsh Shadow we have got here
because of the Spotlight. There is a nice falloff
here on the edge because of the cone angle
being so — in a Cone Angle, keep that to 0.0 —
well, if you want to. But that gives you a really
nice falloff here for that, and then the outer Cone Angle
was whatever that was. Just for the Shadow,
what I do to soften the Shadow, is I lower the Shadow Resolution
here, just slightly. I am not sure even
if that is made for that, but that is the effect
that it has. But then you see that
the problem that we then have is a light
leaking through the shelf, because our Shadow Bias
is too high. I just need to lower
the Shadow Bias so that it effectively is going
to be smaller than the size of the shelf. The problem that we will have is
that if it gets too small, we will have some self-shadowing,
so we really do not want that. It is this very fine line
between those two problems. Yeah, the Resolution Scale
is nice to sort of soften the Shadows a little bit. That is for those lights. Then these ones,
I am not quite sure, sometimes these lights come on.
These stop casting a Shadow, and then they come back on,
see, like that. I think it is some kind of LOD
in the lights, but I have not quite figured
that out. Maybe it is because it is some
optimizing within the interface. Then finally, this Omni here
is casting a light through this lampshade. That was really easy to work
to make this lampshade glow. What is nice is that
it is not casting a Shadow, so if I set up, I do not have the streaks
of the lampshade on the wall because of this sub-Material,
this sub-surface Material. That works really well.
Great. Let us move on, because
the time clock is ticking. I have shown you the build-up
quickly of these lights, so that is the IES
naturally close to the wall have a really nice effect,
that is the down-lighters. That is the Omni by itself, and that is
the Spotlights together. Then if we build
the scene back up, you see that it is very much like this sort
of compositing again. We just sort of add all these
lights on top of each other. Then we can even work
with the Global Illumination, as if we had to render [INAUDIBLE] for that with this
in the Post-Process Volume. You will really see
how the Post-Process Volume really becomes
part of the lighting here where we have got direct
lighting Intensity set low. Then higher, then higher to 1.0. So we have got complete control
over that, after the lighting
has been rendered. Then that is those Spotlights
we looked at. Great, so now moving on
to the exterior scene, great thing about this one,
there is no GI. It is super to work this way;
there is no render and no GI. It is all animated,
all the leaves, all the grass — everything. I am just going to take you
through this walkthrough quickly, because we are
running out of time. But here Effect World is
turned off for the Skylight, so we have got really
the base scene, nothing, just a Reflection here. Then the Skylight is added
with this HDR. It gives us
a nice blue undertone. You see that the detail, obviously
because there has not been any lighting calculation
performed, the resulting lighting
is very flat. Because this is going to be
the color of my Shadows, this is kind of what I am
looking for, a flat, lit Shadow. It comes from a little bit
what I have learned in painting and drawing, where the Shadow area
is left without much detail, and leaves a little bit more
to the imagination. But it does have a tint. That looks correct as a base. You will see, hopefully,
the success for that later on. Here, I am building up
the layers again. If I flip between the two,
you will see that there is no change
in my rendering of the scene, because I have added the sky.
The fog was already taken — well, that sky was already taken
into account by the Skylight having its HDR. Here I am building up
the sky background, and then I am adding the fog
over the rest of the scene. It is very much like
we are working with a compositing package. Then I have added this dome
Blueprint effectively, which is this Material
with a sky on it, which projects it
as a dome sphere, and animates it, makes it rotate
at speeds that you want. That is great,
that adds a little bit of life and animation in the sky. Then you see that when I turn on
the directly light of the sun, and that is made
with a warm color on purpose, it really contrasts, and it gives quite a good render
of the whole thing in the end. That is, again, a very simple
setup, and very effective. The Skylight does a great job of
just illuminating our Shadow areas. I guess we could even add
a bit of Ambient Occlusion here, that I have probably turned off. We will work with that
a little bit more to get those contact Shadows
here working. But generally,
because it is an outdoor scene, the sunlight will have
an enormous effect. Just moving on for that,
the night scene, here again
I just sort of build that up, because it was very theatrical,
great fun to work with again. Here I have just sort of added a little bit of faked
bounce light from the ceiling. This has got some up lighters
in the corners here, up lighting the ceiling,
the white ceiling, which is giving a nice,
soft, warm light to the interior of the house. I tried to replicate
that just with Spotlight, so I did not
have to calculate any baking. Saying that, I probably
could have just put a Lightmass Importance Volume just around the house,
and calculate the baking, the light bouncing,
just for the interior. But I did not do that. This time focused
on the outside, and here I have got
some down-lighters here from the edges,
just flooding a little bit, the edges of the house with this
kind of very soft transition to complete darkness here. Then these flood lights
onto the trees, they were put on top
of the roof of the house, and just projected light
out onto the trees. They have got this kind
of warm color here that I — I actually turned off
the square falloff for these. They are quite uniform, and I have changed
the falloff manually. Then those sort of back ones
that we are sort of more in cool color contrasting,
with the warm for the rest. Then final —
I could not help it — to add the new Volumetric fog, which, yeah, begins to
really make this thing — while the level of realism
that we can achieve, using Unreal Engine today
is quite impressive, I think. That looked great.
That was great fun to play with. Why do I not just show you
quickly how to rebuild this? Okay, so here we have got
a Skylight here, that is just giving —
that is just a blue color. That is just giving a base,
again, this sort of just base flat light
over our Shadow areas. Then just these two inside; so you see those
down-lighters here — where are they — just go perspective
onto these down-lighters here, so that is what is
going on in there. Then we have got
our parameter lights — so again, nothing too fancy,
that Intensity. What is lovely here is that, the way I have worked this,
is that you have got the Folders, so I can just sort of
turn them on and off this way. If I just deselect them —
so that is a great way to work. Then I just select them
like that, and just click on the interface.
If I hide them, if I press G, then I can play
with them completely. Or you can make a Blueprint. But this is incredibly
interactive, right? That is for the parameter and then
the flood lights on the roof, I just turn those on.
Then again, only three there, but I can just play
with them like this. Here, I turned off
the inverse squared. That is why this Intensity
is set on 20.0, normally it would be much higher
if I had the square falloff. Then finally, this on the slope. Then the exponential height fog,
again, is just super, because it is one
of these things that there is
really nothing to do; all you need to do
is just click that, Enable Volumetric Flow of Fog. Here I have just changed
the Albedo color, brought it down a notch. Here, put the Intensity
quite high. But yeah, it is a fantastic
thing to play with, this toy. Just to reiterate,
the performance on this scene is really not great,
but it gives us a nice image to stick at the end
of the PowerPoint. There you go.
If you want to know more, please do check my website.
There are some new courses to be released
very soon about lighting; how to get different
lighting scenarios. Check out on the website, and get in touch
if you need to know more. I will hand back
to Chris for now, and any questions far away?

Lighting Deep Dive for Architectural Visualization | Webinar | Unreal Engine
Tagged on:                                     

11 thoughts on “Lighting Deep Dive for Architectural Visualization | Webinar | Unreal Engine

  • August 3, 2018 at 9:39 pm


  • August 3, 2018 at 9:52 pm

    Great contribution to release the video webinars for all public as should be. Congratulations @Unreal Engine!

  • August 4, 2018 at 7:21 am

    Unreal Engine 4 Lightmap baking takes too long even for archviz. Something you guys should improve upon.

  • August 4, 2018 at 1:57 pm

    Nice tutorial share to https://real3d.org/lessons/lighting-deep-dive-for-architectural-visualization-webinar-unreal-engine/

  • August 16, 2018 at 6:53 pm

    Whats up Fabrice. Why is your voice in a UE4 demo?

  • March 3, 2019 at 10:13 pm

    How to get notifications for webinars

  • April 11, 2019 at 8:05 pm

    So I’m a noob at this stuff. But how do you turn the scene dark???

  • July 3, 2019 at 9:47 pm

    How can I create a level sequencer to capture the GI, refraction…?

  • July 8, 2019 at 1:03 am

    Thank you, very much for taking the time to create this guide and share the information but, dude… collect your thoughts then start recording – pretty sure 15-20 minutes of this hour long clip was "UHHH, soooo, so so so so, ehhhhhhhhhhhhhhhhHhHhhH"

    Great content otherwise though! Thanks again.

  • August 14, 2019 at 11:07 am

    starts the video
    we are running out of time so lets go quickly

  • August 25, 2019 at 5:34 am

    One good thing I found to make or help me make perfect Lightmaps, is to use "Lightmap Templates". These were a god send for me, and I learned this from Warren Marshall, a guy on YouTube here who does some great work. I use these as backgrounds in my UV Grid, and then I use Pixel Snap, to help layout my UVs and snap them perfectly to each pixel in the background of the UV Grid. This template, would be a checkered pattern to help with the snapping and being able to tell were the pixels actually are. I found that planning ahead and aiming for a certain Lightmap Resolution is the BEST method to use when planning and creating Lightmaps for all assets. This makes my shadows look crisp every time. I tend to use 1024 and 2048 as the preferred Lightmap Resolutions for Arch Viz setups.


Leave a Reply

Your email address will not be published. Required fields are marked *