FollowComponent.cpp

#include "FollowComponent.h"
 
#include "Types.h"
 
#include "Components/Core/TransformComponent.h"
 
#include <glm/gtc/quaternion.hpp>
 
using namespace Cogs::Reflection;
 
void Cogs::Core::FollowComponent::registerType()
{
  Field fields [] = {
    Field(Name("target"), &FollowComponent::target),
    Field(Name("offset"), &FollowComponent::offset),
  };
 
  Method methods [] = {
    Method(Name("update"), &FollowComponent::update),
    Method(Name("initialize"), &FollowComponent::initialize),
    Method(Name("cleanup"), &FollowComponent::cleanup),
  };
 
  DynamicComponent::registerDerivedType<FollowComponent>().setFields(fields).setMethods(methods);
}
 
void Cogs::Core::FollowComponent::initialize(Context * /*context*/)
{
  if (target) {
    update();
  }
}
 
void Cogs::Core::FollowComponent::update()
{
  auto transform = getComponent<TransformComponent>();
 
  static float time = 0;
 
  time += 0.1f;
 
  if (target) {
    auto targetTransform = target->getComponent<TransformComponent>();
 
    if (!targetTransform) return;
 
    transform->position = targetTransform->position +
      glm::vec3(glm::mat4_cast(targetTransform->rotation) * glm::vec4(offset + glm::vec3(0, std::sin(time) * 10.0f, 0), 1.0f));
 
    transform->setChanged();
  }
}
 
void Cogs::Core::FollowComponent::cleanup(Context * /*context*/)
{
  if (target) {
    target = nullptr;
  }
}