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You have completed Unity Basics!
You have completed Unity Basics!
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Here we’ll introduce Unity's physics engine by adding a Rigidbody and Colliders to our game objects.
Unity 6 Documentation
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Okay, currently our
game object is just static in our scene,
0:01
so what we need, basically, is gravity.
0:04
Luckily for us, Unity has a built-in
physics engine which makes our jobs
0:07
much easier.
0:11
So to add a new component to an object,
we select it in the hierarchy,
0:13
and in the inspector
we can click add component.
0:17
This opens
a very intimidating select menu,
0:21
but I encourage you to explore
all of the options here.
0:24
I always use the search option here,
0:27
but that's in part
because I know what I'm looking for.
0:29
When just starting out, I would typically
look through the options, or go to Google
0:32
if I was looking for something specific
and I didn't know the name of it.
0:36
So let's click in there and start typing
rigid body.
0:40
Here we see a Rigidbody
in a Rigidbody2D.
0:44
We're making a 2D game,
so we definitely want the 2D option.
0:48
The other is used for 3D applications.
0:51
And now it's seen in our inspector
as a component.
0:55
Easy as that!
0:57
I'm going to collapse this
0:59
sprite renderer since I'm zoomed in here,
but you don't need to do this.
1:00
The Rigidbody2D
component applies Unity's built-in
1:04
physics to the game object
that we place it on.
1:07
We can see by glancing
1:10
at this component's properties
that it has one named Gravity Scale.
1:11
If we hover over this label
we see a tooltip and it says how much
1:15
gravity affects this body. Perfect!
1:19
Let's click play and see what happens.
1:22
Well there it goes!
It definitely has gravity
1:25
now, but it fell straight
through the screen!
1:28
I'm going to separate my scene
and game view
1:31
for a moment to show you further,
but you don't have to do this.
1:33
If I zoom out with the scroll wheel
and click play again,
1:37
you'll see it's just falling forever
outside of our camera's view.
1:40
Again,
don't feel the need to follow me here.
1:43
I just want to quickly give you a visual
of what the camera is doing.
1:45
If I click this button that
1:49
reads 2D, it will change our scene
view to a 3D view.
1:51
This can make things a bit more difficult
when making a 2D game,
1:55
but it shows the camera situation
pretty well.
1:58
You can see here it's essentially
a view box, and anything within it
2:01
and in front of
it will be shown in our game.
2:04
So what we need next,
2:09
logically, is a ground
to catch our circle.
2:11
So let's create another game object.
2:14
Let's go to 2D Objects,
2:16
and Sprites again,
2:19
and this time let's create a square.
2:21
I'm going to right click the Transform
label and reset its position.
2:24
This is something
2:28
I typically do with new objects,
just to have kind of a clean slate.
2:28
We want it at the bottom,
2:32
so I'll select the Move tool with W
and drag it down there.
2:33
I want it to go past the camera view a bit
so that we don't see the background
2:37
beneath it.
2:41
Negative 5 looks perfect.
2:43
Now I'm going to get the scale tool with R
and drag out
2:46
the X scale of its transform
so that it covers the whole camera view.
2:49
You can go outside the camera lines
here too.
2:53
Okay, let's click play again
2:57
and see what happens.
2:58
Oops, it fell right through it!
3:02
What we want is for these two objects
to collide
3:05
with each other, and to achieve that,
we need another component.
3:07
You guessed it, a collider.
3:11
Collisions are one of the most important
aspects of game development.
3:14
If everything passed through everything
else, we wouldn't be able to make anything
3:17
very fun.
3:21
Players couldn't run on the ground, cars
couldn't crash into each other, and so on.
3:22
So let's click Add Component
and search for Collider.
3:27
We'll see a lot of options here,
but we're working with a square,
3:31
so the one we want is Box Collider 2D.
3:34
Again,
make sure you're using the 2D option.
3:37
Now it's hard to tell, but
3:41
it's actually been automatically applied
to the exact shape of our sprite.
3:42
If we enable this edit
collider button here and zoom in a bit,
3:46
we'll see four green squares
on each side of the object.
3:50
We can click and drag these to edit
our invisible collider shape.
3:53
This means we have the freedom
to have parts of our objects
3:57
pass right through things
and other parts detect collisions
4:00
I going to undo this though
because I just want the entire box covered.
4:04
There also the offset and size fields
4:08
here to adjust this collider shape
if we want to.
4:10
Okay, now
4:14
we need to add one to our circle as well
or it'll still pass right through it.
4:14
So let's select our player,
and I'm going to collapse these components
4:18
to free us up some space,
and then add a component.
4:21
Oh, how convenient,
our collider search is remembered,
4:25
and this time
we want a Circle Collider 2D.
4:28
Again,
4:32
it's applied it perfectly
to the edges of our sprite.
4:32
Also, real quick,
these colliders are perfectly forming
4:36
to these two shapes because
we're using a square with a box collider
4:38
and a circle with a circle collider,
and they play well together.
4:42
If we had a human shaped sprite
for example, we won't be getting this
4:46
perfect formation obviously,
but don't worry about that stuff yet.
4:49
Let's click play and see what happens.
4:53
Alright, we've got collisions!
4:57
I'd say this wraps up this game.
5:00
Thanks for watching everyone!
5:01
We'll see you next time.
5:03
Alright, kidding, of course.
5:04
This achievement may seem small,
but this is huge in the world of game
5:07
development.
5:10
We have physics and collisions
already working and it was as simple
5:11
as that to implement. Nice job.
5:14
Next, we need to get this circle doing
something besides, you know, just falling.
5:17
So in the next few videos, we're going
to be implementing the most crucial aspect
5:22
of creating a game. Capturing user input.
5:26
I'll see you there. you
5:29
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