I don't think there's much debate about
whether Assassin's Creed Origins is a
good-looking game. It is stunning.
From sweeping deserts to lush marshland
environments, Assassin's Creed Origins
plays its cards right. But being a
console title predominantly, the
developers and artists needed to squeeze
all the juice out of your Xbox or
Playstation that they could and one of
the ways they do this is by using low
detail geometry in smart ways. So in this
video I'm going to cover a few different
tricks that are used by Assassin's Creed
Origins and a lot of other games to
create low poly geometry that still
looks good and helps to trick the player
into thinking there is more graphical
detail than they might think. And I
thought I might keep it centralized and
contextual by getting all of these
tricks from this farm. I am warning
everyone now most of what we are about
to cover is things that you cannot unsee
so if you aren't the kind of person that
likes to look behind the curtain then
don't say I didn't give you a heads up.
Hey, this is Gigity McD and you are
watching design run. A casual series of
videos where we break down the design of
one game in particular. Let's get into
these tricks. Number one is the good old
crossed planes trick. One of the oldest
tricks in the book for 3d geometry is to
use crossed planes to create objects
with a lot of fine detail cheaply. This
works because we don't consider things
like trees as objects that have a lot of
detail. We look at the whole and process
it as a tree. Which is why when we get a
crude drawing like this we still know
instantly that it is a tree. Taking this
idea, games have been creating trees by
having a modeled trunk and flat planes
with leaf textures on them for ages.
Here's some footage from Jak and Daxter,
a game that came out from the start of
the ps2 lifecycle, although this footage
is from the ps4 port. Running down like
this everything looks fine but if we
stop and really scrutinize the
vegetation, you can easily see that it's
a lot of flat low poly geometry.
Assassin's Creed takes advantage of this
all over the place.
The trees are the obvious one. Mixing up
the angles and directions of this low
poly branch geometry so that from a
distance it looks like leaves but
getting close up you can see that even
the berries are part of the texture on
the branches and they disappear as you
get perpendicular to them. Similar
techniques get used for the crops and
these flowers. From the angle of the
third-person camera it looks pretty good
but when you swing overhead the illusion
falls apart a little. These little white
flowers actually gave me a bit of
trouble to work out but if we take out
our predator bow and look down along the
edge of the field, I think what is
happening is the stem is made up of
strips which we'll discuss in a second
and the bulb/flower at the top
has two little planes with the flower
texture that move independently in the
wind. Which turns out very convincing.
Number two, thin peals of geometry. So
similar to number one, a lot of these
props have solid low poly bodies and
then thin peals of geometry sticking
at the top. Then the detail work is
achieved mostly by the texture. This set
of bales is solid and looks pretty good
but once again if we swing over the top
with the camera the effect becomes very
obvious but from the angle that the
player will have the camera most of the
time this will look great and perform
well too. There is a similar thing going
on with this hay fence, where the bottom
is modeled as normal geometry with
dimension and to add detail without
blowing the poly count out of the water,
strips are again used to add the detail
in at the top where the ends of the hay
would lean over. This technique is also
used for things like ferns or
palm trees to give that feel that the
leaves are leaning over under the
influence of gravity which also adds
natural dimension without increasing the
amount of geometry.
Number three is taking advantage of
terrain textures. You can see around this
fire that the heat has burnt the ground
in places. Well ash is one of those
things that we consider as a whole
rather than as individual pieces of ash.
So here it looks like the artists have
taken advantage of the terrain running
underneath the fire. So terrain is
usually a massive flat tile that gets
adjusted and molded into the shape to
form the ground for the world and then
to detail it most game engines have a
set of brush tools that you can load a
pallet of textures into. These then get
painted onto the ground to create things
like paths. Here it seems the artist used
an ash texture and just painted it under
the fire to give the illusion of
scorched earth and the only additional
asset would be the texture. This
technique could be used for all sorts of
things though. Number four,
mesh warping. Hay bales you can hide in
like this are a staple of the Assassin's
Creed universe but that doesn't mean
that they aren't subject to low poly
tricks. If you look at this hay bale as I
hide in it, you can see that the top of
the mesh bobs to sell that interaction.
Combine this with some hay particles and
it's a pretty satisfying action. But when
you look at the mesh of the hay bale
it's pretty simple and the warping and
the texture are doing most of the work
to sell that interaction. Similarly, when
you run through the flowers and crops
etc. they look really good when you are
sprinting through them but if we slow
down and really consider what is
happening, you can see that there seems
to be a small sphere at Bayek's feet that
interacts with the plants. Warping the
mesh around the sphere and then pushing
it underneath the terrain surface. This
looks silly when you walk slowly at the
edge of the field but that mesh
deforming around the sphere is what
makes running through the flowers look
so good. Sell it with some cheeky hand
animation and these low poly planes are
starting to come in really handy.
Number five, texture warping. I think it's
worth talking about this awning for a
second for two reasons. The first is I
think the artists are getting a lot of
realism out of simply folding over the
edges like they have and tucking it up
in the corners. It adds dimension and
realism to the awning that otherwise is
just flat geometry with the texture. The
other trick they use is easy to see if
you jump up on top of the awning. The
awning itself does not sway in the wind,
instead the texture on the awning warps
ever so slightly. I'm not an artist so I
don't fully understand the tech behind
this but that sort of warping of the
texture is what the devs are using to
try and sell the idea that
wind is running underneath this cloth.
Another trick we can use to help detail
our environments. Last but not least,
Number six, combining things together. We've already quickly went over the idea
of a tree having a bunch of fine detail
but being processed by the brain as a
whole. Well, we can use this idea for the
props that we scatter around our
environments. These bags of what I'm
going to guess is grain look quite low
poly, you could chuck them around
everywhere by themselves or you could
stick them on top of something else.
Place that next to something else again.
Tie it all together with some rope and
you have a bunch of low poly objects
that the player will process as a whole
like supplies or cargo. Similarly, these
cucumbers or pickles or whatever they
are look okay but are fairly low detail
but if we use a bunch of them, and tie
them to a broken crate? It makes no sense,
I don't know why you would want to do
that but it looks and feels like a new
object and you are less critical of each
one's individual detail. And it doesn't
have to be random stuff either, here is a
bunch of brick only assets that have a
small story behind them as a whole. You
can see they even use some assets that
are chunks of four or five bricks, this
one and this one. And so I hope you liked
those little observations. SUBSCRIBE to
the channel and LIKE the video and I'm
sorry that this video was late this week.
I have a bunch of next week's video done
already so back to the normal schedule
on Fridays and keep an eye out for a
channel update in a few weeks as things
will be changing for a month or two
over April and May. Thanks everyone and
see you Friday!
