pokemon/actor.hpp

#pragma once

#include "coordinates.hpp"

struct actor_t
{
  enum direction {
    up,
    down,
    left,
    right,
  };

  world_t world;
  enum direction facing;
  bool moving;
  uint8_t frame;

  constexpr inline offset_t offset()
  {
    switch (facing) {
    case left:
      return {-frame, 0};
    case right:
      return {frame, 0};
    case up:
      return {0, -frame};
    case down:
      return {0, frame};
    default:
      return {0, 0};
    }
  }

  // call tick() before move()
  constexpr inline void tick()
  {
    if (!moving) return;

    if (++frame == 16) {
      moving = false;
      frame = 0;
      switch (facing) {
      case left:  world.x--; break;
      case right: world.x++; break;
      case up:    world.y--; break;
      case down:  world.y++; break;
      }
    }
  }

  constexpr inline void move(enum direction dir)
  {
    /*
      m 1 . 2 . 3 . 4 .
      | - | - | - | - |

     */

    if (moving) return;

    frame = 0;
    facing = dir;
    moving = true;
  }
};