All language subtitles for 4. HP System

Let's now look at the HP system.
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You'll find this system in the demo folder.
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prefabs/systems/HPSystem
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The HP system is a critical part of the project.
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It allows objects to have life and get destroyed if they take enough damage.
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Most of the code here is actually to update the health bar (UI) associated with it.
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And all of the children objects here handle the health bar and the health healing effect.
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The lasted time, which when it'll get triggered, it'll regenerate health and the health regeneration
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animation.
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So, functionality wise HP system has two important features the maximum HP and the current HP. When take
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damage is called.
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This is the most important function because when things damage is called, then we need to subtract
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the amount from the current HP and if it reaches zero.
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If the current HP reaches zero for the first time, we can check if it reaches zero, but we don't
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know if it's the first time.
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This is what is_alive is for. Because if is the first time, then is_alive is true and then
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it gets false and then it won't be true for the next time the current HP gets below zero. And the HP
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system actually has two signals on_damage_taken and on_destroyed.
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When it gets hit on damage taken happens.
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And this is important for the enemies when they get hit by the player to actually acquire the target
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and when on_destroyed happens.
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This is important because we need to actually destroy the object, but you don't want it to be destroyed
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here in HP system because there are some other steps that need to be taken to destroy other objects (referenced by this one).
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It's important to get the signal and then use it for later purposes.
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The other main functionality of the HP system is regenerating health.
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As you can see here, if the HP system receives damage, the last hit timer gets reset.
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Once the lasthit_timer
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is 0
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Then the should_heal variable is set to true.
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And this means that from this moment on, the HP will heal itself.
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How is this happening?
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At every frame, if should heal is true, then the current HP gets added.
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The healing factor * delta, and if the current HP is equal or more than maximum HP then we set
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it to be maximum HP. And then the animation player stops the animation.
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This is just an animation that sets everything to zero and of course it updates the UI.
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The UI is basically this bar, which is actually a gradient that has two values.
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I'll quickly show you what it does.
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First, we get the gradient from this one and we set the offsets of this one.
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But when update HP ui happens, it sets the two colors.
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The first one with index zero is red and then the green one because first we have everything green.
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The red will start from the left, but it will start from nothing.
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And then we set the offsets of these.
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If the player or the enemy gets more and more damage, these will change.
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I'll quickly show you.
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This is the red it has like nothing happening, but once it starts taking damage, the offsets move.
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The red is more than green
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now. If I go far away, then at some point my healing will kick in.
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This is the healing animation. It's just basically fade in / fade out for that background, but it will
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actually slowly heal me.
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And this can be tweaked here at the Heal Factor, so you can adjust it as much as you want.
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Lastly, what I want to mention is that the system is meant to be integrated below the kinematic body
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of either the player or the enemy.
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And this is needed because once this object gets detected from the projectile collision, they will
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ask for the HP system directly.
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It's important for the HP system to be here.
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Otherwise, if the hierarchy were different for the player and the enemy, then it would have been a
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mess of a code to make everything work.
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This is why it's important that the HP system is a child of the object that takes the collision directly.
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Basically, this is the HP system.
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I hope you like it and leave me a comment if you did.