PhysicsBodyStateUpdaterRK4.java
package com.hypixel.hytale.server.core.modules.physics.util;
import javax.annotation.Nonnull;
public class PhysicsBodyStateUpdaterRK4 extends PhysicsBodyStateUpdater {
private final PhysicsBodyState state = new PhysicsBodyState();
public PhysicsBodyStateUpdaterRK4() {
}
public void update(@Nonnull PhysicsBodyState before, @Nonnull PhysicsBodyState after, double mass, double dt, boolean onGround, @Nonnull ForceProvider[] forceProvider) {
double halfTime = dt * 0.5;
this.computeAcceleration(before, onGround, forceProvider, mass, halfTime);
this.assignAcceleration(after);
this.updateVelocity(before, this.state, halfTime);
updatePositionBeforeVelocity(before, this.state, halfTime);
this.computeAcceleration(this.state, onGround, forceProvider, mass, halfTime);
this.addAcceleration(after, 2.0);
this.updateVelocity(before, this.state, halfTime);
updatePositionAfterVelocity(before, this.state, halfTime);
this.computeAcceleration(this.state, onGround, forceProvider, mass, halfTime);
this.addAcceleration(after, 2.0);
this.updateVelocity(before, this.state, dt);
updatePositionAfterVelocity(before, this.state, dt);
this.computeAcceleration(this.state, onGround, forceProvider, mass, dt);
this.addAcceleration(after);
this.convertAccelerationToVelocity(before, after, dt / 6.0);
updatePositionAfterVelocity(before, after, dt);
}
}