Animation.hpp

//
// Created by jibbo on 3/15/21.
//
 
#ifndef ENGINE_PROJ_ANIMATION_H
#define ENGINE_PROJ_ANIMATION_H
 
#include <utility>
#include "MeshRenderer.hpp"
#include "Scene.hpp"
#include "Time.hpp"
#include "Texture.hpp"
 
namespace Engine {
  struct Animation {
  private:
    bool singleTexture = true;
 
    size_t m_currentFrame = 0;
    size_t m_lastFrame = 0;
    float time = 0;
    float spf = 0.1f;
    float scale = 1.f;
  public:
    Ref <MeshRenderer> renderer = nullptr;
    std::vector<Ref<TextureLookup>> lookup = std::vector<Ref<TextureLookup>>();
 
 
    static void Update(const Scene &scene) {
      auto ecs = scene.GetECS();
      for (auto e : ecs.GetEntitiesWith<Animation>()) {
        ecs.GetComponent<Animation>(e)->UpdateTime();
      }
    };
 
 
 
    Animation() = default;
 
    Animation(const Ref <MeshRenderer> &meshRenderer,
              const std::vector<Ref<TextureLookup>>& textureLookup)
              : renderer (meshRenderer),  lookup(textureLookup) {};
 
    void UpdateTime() {
      time += (float) Time::dt * scale;
 
      if (time >= spf) {
        m_currentFrame++;
        time = time - spf;
      }
 
      if (m_currentFrame >= lookup.size()) {
        m_currentFrame = 0;
      }
 
      // for negative animation
      if (time < 0) {
        m_currentFrame--;
        time = time + spf;
      }
 
      if (m_currentFrame < 0) {
        m_currentFrame = lookup.size() - 1;
      }
 
      if (m_currentFrame != m_lastFrame) {
        drawFrame();
      }
    };
 
    virtual void drawFrame() {
      auto texData = lookup[m_currentFrame];
      if (renderer == nullptr || texData == nullptr)
        return;
 
      renderer->map = texData->map;
      renderer->texture = texData->tex;
      renderer->mesh = CreateRef<Mesh>(Mesh::quad(glm::scale(glm::vec3{texData->width, texData->height, 1})));
    };
  };
 
 
}
 
#endif //ENGINE_PROJ_ANIMATION_H