Modifiers
PAL has a unique feature called a modifier, they can be used to change things about an animation.
They can do all sorts of things, like mirror an animation, change it's speed, or apply transformations to a specific bone.
PAL offers many built in modifiers, but you can also make your own modifiers. I will go into detail on both in this page.
Modifiers can be added to an instance of the AnimationController or ModifierLayer class.
You can use the addModifier, addModifierBefore or addModifierLast method to add a modifier to your animation.
Modifiers run in order, the modifier with the lowest index runs first and has priority over all the other modifiers.
You can also use the removeModifier, removeAllModifiers, or removeModifierIf method to remove modifiers.
Modifiers last for the lifetime of the animation controller or modifier layer they're attached to unless removed. Some modifiers can remove themselves, which I will explain in detail later in the page.
How to make your own modifier
In order to make your own modifier you need to make a class that extends the AbstractModifier class.
Here you can override many methods in order to change how the animation is processed.
Here is a list of them:
tick: Called every game tick, useful for keeping track of time.
setupAnim: Called every frame, useful for getting the tickDelta in order to make smooth translations.
get3DTransform: The most useful method, it's called for every bone, and gives you the bone so you can apply whatever translations you want to it.
canRemove: If true it will tell the host to remove the modifier.
Don't forget to call super when you override a method!
How modifiers work is that calling super calls the next modifier in line, and the last modifier calls the host.
If you don't call super the host animation will never be called.
All position translations are measured in pixels, and all rotations are measured in radians.
The axes work the same as in Blockbench so:
Forward is negative Z, right is positive X, and up is positive Y.
You will also be able to access a variable called host which is the animation controller or modifier layer hosting the modifier.
If you are sure your host is a controller you can also use the getController method.
Built In Modifiers
Here is a list of all the modifiers included with PAL by default and how they work:
AbstractFadeModifier:
Can be used to fade in or out of an animation.
You should usually use the replaceAnimationWithFade method in the host, rather than add this modifier yourself.
Made using a static method in the class rather than a constructor.
When fading in the modifier removes itself when it's done, but not when fading out.
SpeedModifier:
Multiplies the speed of the animation by the given value.
The value can be changed after the creation of the modifier.
AdjustmentModifier:
Can be used to apply specific translations to the desired bones.
MirrorModifier:
Mirrors the animation... (Some of these modifiers are really self-explanatory!)
For example if you have an animation that uses an item with the right arm, you can mirror it to use the left arm instead.
MirrorIfLeftHandModifier:
Same as the mirror modifier, but is only applied if the client sets it's main hand to the left hand.
FirstPersonOffsetModifier:
Meant to be used with the first person follow camera mode turned on. (Read more here)
Usually with that mode turned on the arms are out of frame, so this modifier raises the body up by the specified amount (or 1.92 pixels by default) only in first person so the arms are in frame.