Why Unreal Engine 5.1 is a Huge Deal

The first major update for UN rolling of five just released called 5.1 and it is a huge deal .

The reason why is one word and that is foliage .

Since un rolling of five came out , it introduced a revolutionary new way of rendering geometry called NANITE to briefly sum up nanite .

Every object you see in computer graphics is composed of tiny flat planes of geometry called polygons .

And the more polygons you have in your environment , the longer it will take to render .

This is why video games have developed a system called a level of detail or L O D for shorts .

The further away an object is from the camera , the less polygons it will use to render that object .

This makes games run faster since there's less polygons that have to be rendered .

But it is very time consuming to create all those L O DS .

NANITE replaces L O DS because it uses dynamic level detail .

This means you can have an object with millions of polygons without any L O DS because polygons dynamically deform lowering the amount of poly on the object .

A good example of Nanite in use is this desert .

If I come up to lit nanite triangles , we can see nanite in action , every color is an individual polygon and there are millions of them without a single L O D being used .

The biggest issue with nanites is that it did not work with foliage .

This means we still have to rely on level of detail for foliage like shrubs , grass and trees , trees generally use billboards as the lowest level of detail , which is just a flat plane with a texture that as you can see does not look very nice .

Here is an example of what a billboard looks like I have on real engine five opened up .

And in this environment , all the trees are using level of details because that was the only option .

Now , if I move my camera far away , you can see that the trees change L O Ds until they are using billboards and the transition looks pretty bad .

Notice how even the shadows disappear because billboards only block light if it's facing it .

Now , in Unreal engine 5.1 , we finally get nanite foliage to enable NANITE on foliage is pretty simple .

You want to open up the static mesh and within here , make sure enabled NANITE support is turned on .

And this is unique for foliage , select preserve area .

That's how if you aren't too far away , the object won't disappear and then press apply changes .

I went ahead and did the exact same process to all the trees in this environment .

Now , when the camera flies away , there is no L O D transitions or billboards , the trees retain the same quality as if they're being viewed up close and the shadows do not disappear at long distances .

There is no loss in performance .

In fact , we gain an extra five frames .

So it is more performant than L O DS .

So Nanite not only looks better , it runs better in certain scenarios .

Here's another example showing the power of Nanites .

This is what it looks like without nanites .

The level of detail is noticeable because you can see that in the distance the trees are just textures .

Also the lighting is casting incorrect shadows and this is the same environment .

But with Nanite enabled , the trees far away are no longer being faked by inaccurate textures .

All the trees are real geometry that exists in the world and we did not lose any performance .

I wanted to push the limit of Nanite foliage .

So I create a forest that is four square kilometers in total .

There's over 100,000 trees in this environment and I'm still getting decent performance .

And as a reminder , this is all in real time , this level of density was only possible in pre rendered movies .

Also , it makes life easier .

We don't need several different versions of an object for L O Ds anymore .

On top of Nanite foliage now interacts with light accurately in real life .

Light passes through or bounces inside of leaves creating subsurface scattering .

Previously , this did not work with U E five's lighting but now it does this is foliage and unreal legend 5.0 .

Notice how the shadows are way too dark and unrealistic and here's foliage and unreal legend 5.1 .

Now light is passing through the leafs and illuminating the ground which looks a lot nicer .

This is a subtle change but it does make a big difference .

They also added nanite landscapes , but it is feature incomplete and still in early access .

Hopefully in the next version of Unreal , we get proper nanite landscapes .

Of course , foliage is not the only major change when Unreal I release , it introduced a new lighting system called Alumin which gave us high performance dynamic bounce lighting .

And while it was revolutionary , there was one big issue and that is it did not work with translucent materials .

So glass and water reflections were pretty much broken .

It was so bad that I was recommending people to not use glass since the reflections were completely different from the environment .

Right now , I have a previous Unreal engine version open up and this house's windows , reflections make no sense .

You can see that we're getting reflection from nowhere and same thing for this glass jar .

And this is the same environments in 5.1 .

But you will notice that there is no change yet in the reflections .

And that's because we have to go into our post process volume and under reflections , lumen reflections , make sure high quality translucency reflection is turned on .

Now we get a 1 to 1 reflection with our environment .

We could better see this in the glass cupboard .

There is an accurate reflection of the room .

We can even see the table and windows within that reflection .

The only downside is that the setting does a lower performance .

So there is a cost but nothing is free .

And now reflections work water isn't broken anymore because of this new setting .

Before this update to get true reflection , we would have to use plainer reflection and then manually move it to lining up with the water .

Now , I can just enable translucent to get realistic while reflections without having to use a reflection capture .

This also fixes reflections for large bodies of water .

Notice how on the side of the viewport , we have weird reflections .

This is because by default , unreal is using screen space for translucent reflections .

So that's why we get this artifact and to get rid of it .

Now , just within the post process volume , activate high quality translucency reflection .

So now we get accurate large body reflections without any artifact .

Also besides loin reflections working with glass of water .

Looming , global illumination has seen massive improvements .

Lummi now has a much more accurate bounce lighting because it is bouncing light from the objects surface instead of a Vauxhall approximation .

What this means is that our environment is indirectly illuminated more and there's less noise right .

Here is a simple room with a point light in the old version .

And here it is in 5.1 , the shadows are more illuminated and we got rid of the weird occlusion in the corners .

Here's another example of just indirect sky lighting in version five .

And here it is in 5.1 , you can tell that the secondary bounces are more accurate and powerful .

And finally , there's a lot less noise when using emission materials .

In this example , there's a lot of noise when I move the light around .

And here it is in 5.1 , there is no noise .

You can't even tell that this is real time .

It looks path traced loin wasn't the only lighting system that got approved .

Now , the path tracer supports sky and atmosphere just make sure in your post process volume under path tracing rares atmosphere is enabled also path tracing .

Now finally supports decals and light functions .

For those who want to use traditional light baking .

The GP U light mass has seen massive improvement .

First off , the light mass works at release , it was crashing .

But now since it is more stable , the quality of the lighting is better and the denoyer has improved in dark areas .

Also the GP U light mass now supports sky and atmosphere right out of the box .

Besides lighting , there's also an interesting change to how large unreal levels can be in past versions of Unreal .

If you are really far away from the world origin , Unreal engine starts to break .

For example , I'm an Unreal engine four and I'm very far from the origin , the widgets are starting to break apart because Unreal can't calculate what is happening that far away .

Now , in 5.1 , the recommended area for an environment has expanded from 22 kilometers to 88 million kilometers .

So as you can guess , we can create some pretty large worlds now .

And finally , the last major trade of note is animation with the sequencer animating anything in unreal is done in the sequencer with key frames .

And if you want to move a sequence of key frames earlier or later in the timeline , you have to select each one individually .

For example , let's say maybe I want this ship to fly off earlier .

What I'm going to have to do is hold down shift and select every single key frame and then move them back .

That's how the animation starts .

The ship is already flying off .

5.1 makes this process a lot easier with layer bars which make reim keyf frames , a breeze .

Instead of selecting each key frame individually , I can select the bar as a whole which will move all the key frames of the objects with it .

So with one click , I can re time the animation .

That's how it's sooner instead of selecting all of them those were all the most important major changes of Unreal engine 5.1 .

Now , this was just my opinion .

Of course , there are hundreds of other new features and bug fixes .

So if you are curious , I recommend you check out the release notes in the description below .

If you want to keep up to date with everything Unreal Engine , make sure to subscribe to this channel .

Unreal is more important than ever because half of all announced next gen games are being made on U E five .

There's no better time to learn unreal legend than now .

Luckily for you , I have an entire free course right here on youtube which goes over all the essentials to learn U E .

You can check it out in the description below .