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‫Welcome back.

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‫Now, if we start the game and we check one behavior, which is if we cut our oranges, they will also

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‫stay in the game infinitely.

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‫So we have taken care of our oranges.

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‫They will get deleted after a certain amount of time.

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‫But our cut oranges not so let's change that.

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‫Let's go into our script and in this case, into our fruit script.

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‫So here destroy insert dot game object after 5 seconds.

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‫So this instantiated game object, which is our created slice sliced fruit, will be deleted after 5

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‫seconds.

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‫So let's have a look, if that's true now.

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‫Now I'm gonna slice and let's see if those orange cut game objects get deleted after 5 seconds.

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‫And as you can see, they are gone.

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‫Those things are very important.

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‫If you don't take care of those things, you might run into performance issues.

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‫And that's not that big of an issue with a PC, which has plenty of powerful hardware, but it's a problem

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‫with smartphones.

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‫So really be careful with creation of game objects and deleting them.

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‫All right.

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‫Next, let's create the blade.

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‫So let's create an empty game object and call that one blade.

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‫Now let's reset the transform position and let's add a component, which is a trail renderer.

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‫So there's the thing called trailer renderer.

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‫Let's just use that.

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‫Save the script and check it out.

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‫And if we move around and let's play around with the X and Y value, and as you can see now, it creates

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‫this magenta, which means we don't have the correct material for our blade yet, so let's create a

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‫material for that.

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‫Now let's go into our assets folder and create a new folder in order to create a material for it.

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‫So material and actually materials, plural.

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‫And in here, I want to create a new material and I'm going to call it Blade.

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‫Now, it needs a color, of course, and I'm going to take a light blue, actually, maybe a bit more

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‫powerful just like that.

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‫You can take any color that you like, so I'm just going to take this blue.

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‫Now let's check out our blade and it needs here material.

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‫So click on materials and it says there is one material with none in here.

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‫So there's no material in the element zero.

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‫Let's drag that in there.

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‫And if we test that now and move our blade back and forth, we will see that there is our blue material.

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‫Now what we want is that our trailer renderer follows along our mouse and there is a functionality that

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‫does that.

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‫So it will check out the vector three values.

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‫So a3d value.

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‫In our world, of course, our game is a 2D game, but still the mouse is within a 3D world and we're

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‫just going to use the 2D components that are relevant for us.

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‫All right.

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‫Now, if we look at our trade renderer, we see that it stays on the game for quite a while.

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‫And that has to do with this time.

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‫And let's just change that to 0.2.

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‫So it will only be alive for 0.2 seconds, which means it will be a little trail, but it will not be

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‫a very long trail here.

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‫Let's test that.

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‫Let's run it again and change the position of our X value.

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‫As you can see, it doesn't stay alive for quite a while.

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‫It only very only has a very short life.

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‫And of course, it's also way too wide because we shouldn't have this huge cut or this huge blade look

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‫in our game.

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‫So let's go with 0.1 and let's see how that looks.

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‫Let's play around with the X value.

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‫And there you see, this is how it could look like.

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‫So this is how our our trail will look like.

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‫Now, in order to have a nicer look, so actually I'm going to make the game scene a little bit bigger

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‫so we can see it a bit better.

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‫So I want to change the looks of my trail because currently what it does, it is always 0.1 and we want

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‫to change that.

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‫So let's add a key now.

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‫Let's drag the center here to the top and let's add another key here at the end and let's drag it to

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‫the bottom.

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‫So let's have a look what that means.

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‫So if we move our X position, as you can see, it looks more like a cut with a knife.

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‫You can only see it very quickly, but it will make much more sense as soon as we have our mouse functionality

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‫implemented.

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‫Great.

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‫So next our blade will need a rigid body so that it can move and has a physical impact into the game.

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‫Because what we want to have is of course, if we slice with the blade, which will follow along with

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‫our mouse, if we slice through an object, we want that object to be impacted.

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‫And in order to do that, let's go ahead and add a rigid body to DX and it should be kinematic.

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‫What that does is it tells our blade that it shouldn't be influenced by other objects, but it will

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‫still influence other objects.

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‫So for example, it will still influence our fruits, but the fruits will not drag or push off our blade.

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‫And the collision detection should be continuous here as well because we want to have a very fast collision

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‫here.

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‫All right.

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‫Next, we want to have a script which, of course, takes care of this beautiful behavior that we've

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‫just seen just with the mouse so that it doesn't follow along the X and Y position that we have set

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‫here in our transform component, but it actually follows our mouse.

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‫So let's call that script blade and let's open that script up.

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‫And in here we will use the awake method instead of our start method.

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‫And in here we will actually create a rigid body, private or B or rigid body, which I'm going to call

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‫RB and let's initialize that RB with get component rigid body to DX.

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‫What that will do is it will simply take the rigid body component from the blade itself because the

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‫blade contains that script.

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‫So it will take that rigid body here.

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‫Next, we need a method which will take care of our blade following our mouse.

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‫So let's create a new method, private void set, relate to mouse.

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‫So this method will take care of setting the blade to the position of our mouse and we simply change

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‫the rigid body.

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‫So the RB position to camera dot main that screen to world.

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‫Point transforms position from screen space into world space.

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‫So that's exactly what we want here.

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‫And now we simply say the input should be our mouse position.

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‫So wherever our mouse is in comparison to the world, that's where we want the rigid body to be or the

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‫rigid body of our blade to be.

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‫And that will give us the slide.

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‫Look, we will see that in a second.

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‫And of course, in our update method, we will constantly call the set blade to mouse in order to keep

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‫it up to date so that it always follows the follows along our mouse.

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‫So it will change the position of the rigid body with every single frame based on where our mouse is.

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‫All right, so let's go back to the Blade script.

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‫And here there is a little thing that we need to solve.

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‫So in some cases it might work for you.

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‫So if you start the game, you will already see the mouse being followed.

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‫But in other cases it will not work because the mouse position itself is a 3D point, but our world

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‫is a 2D world, so now it doesn't always calculate it correctly.

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‫So in order to fix that, what we will need to do is we create a new variable called mouse position

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‫or mouse pose, and we set that to input mouse position, which is the one here.

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‫It's the same position.

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‫But now what we do is we set the Z value of our mouse position to the value of ten.

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‫So that means that this is going to be the distance

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‫of ten units from the camera.

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‫And now what we can do here is we don't hand over the input mouse position, but we hand over the mouse

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‫pose.

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‫Now let's save that.

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‫Let's go back to unity.

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‫And by the way, and this ten here actually is this minus ten here.

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‫So we go ten further in in order to get the correct position.

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‫All right.

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‫So let's try that again and now actually get a null pointer exception.

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‫And here, of course, judge, that it should be a week.

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‫Okay.

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‫So now let's check that out.

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‫Let's start the game again.

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‫And let's see.

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‫There you are.

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‫Our plate is being followed.

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‫So this is the blade effect that we have now.

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‫So if we swipe through, we, of course, now want to delete or we want to cut the fruits.

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‫So let's do that.

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‫All right, so now let's cut the fruits.

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‫Let's go into our fruit script.

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‫And in here we are going to add an on trigger enter event on trigger enter to DX.

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‫So we call this method and we say whenever we collide with the blade, we want to go ahead and create

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‫sliced fruits.

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‫So what that will do is go ahead and cut our fruit.

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‫So let's create a blade object here.

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‫Blade B we take the collision dot get component and we call it blade or or actually we get the blade

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‫itself.

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‫So if there is a component called blade with the object that we collided with, then create an object

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‫called B, which is of type blade and then we check if there is no B, then just return.

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‫And what that will do is, well, it will do nothing any more.

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‫So it will just get out of the call of this on trigger enter event, but otherwise go ahead and create

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‫a sliced fruit.

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‫So now we won't do that in the update method anymore.

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‫So let's get rid of that.

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‫We will do it however in the on trigger enter.

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‫So we will create sliced fruit whenever we collide with the blade.

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‫And if we don't collide with the blade, then just return it to nothing.

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‫So let's check that out.

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‫Let's run our code.

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‫Well, actually, before we try that, let's add a collider of more to our blade, because currently

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‫it doesn't have a collider.

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‫So let's create a collider going.

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‫Going to add a.

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‫Circle Collider here.

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‫And before we test that we of course need to make that is trigger and let's see if our fruit is a trigger

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‫as well.

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‫So let's go to our orange or orange should be a trigger as well.

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‫So let's go ahead and try that again.

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‫Now, if we slice through our fruits, we can see that they get cut.

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‫But as you might also see, it's not perfect yet.

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‫So we will have to play around with the values of our radius here.

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‫So let's go with a radius of let's go into the scene and see how big our radius is.

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‫So let's go with 0.5.

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‫Maybe that would be the radius if we compare it to an orange.

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‫So let's drag an orange in here.

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‫That would be too big.

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‫You might guess so let's go with 0.3 maybe or oh point.

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‫Well, actually, as soon as we hit the orange, we already cut it.

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‫Right.

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‫So all point three should be the right value.

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‫So now blade is exactly the same size as the orange.

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‫So as soon as we hit it, we should be good.

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‫So let's try that.

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‫And now let's cut some fruits.

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‫Well, and as you see, we can slice our fruits.

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‫Great.

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‫All right, so see you in the next video where we are going to add the green to our game.