src/simulation.cpp


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115

#include "simulation.h"

#include "consts.h"
#include "level.h"

void Simulation::tick(
  double dt,
  const Uint8* keystate)
{
  for (id_type id : active_)
  {
    Entity& entity = entities_.at(id);

    // Control
    if (entity.controllable &&
        !entity.moving)
    {
      if (keystate[SDL_SCANCODE_LEFT] &&
          entity.gridPos.x() > 0 &&
          level_.getTileset().canPlayerMoveTo(
            level_.at(entity.gridPos - vec2s { 1, 0 })))
      {
        entity.moving = true;
        entity.destPos = entity.gridPos - vec2s { 1, 0 };
      }
      else if (keystate[SDL_SCANCODE_UP] &&
          entity.gridPos.y() > 0 &&
          level_.getTileset().canPlayerMoveTo(
            level_.at(entity.gridPos - vec2s { 0, 1 })))
      {
        entity.moving = true;
        entity.destPos = entity.gridPos - vec2s { 0, 1 };
      } else if (keystate[SDL_SCANCODE_RIGHT] &&
          entity.gridPos.x() < (level_.getSize().w() - 1) &&
          level_.getTileset().canPlayerMoveTo(
            level_.at(entity.gridPos + vec2s { 1, 0 })))
      {
        entity.moving = true;
        entity.destPos = entity.gridPos + vec2s { 1, 0 };
      }
      else if (keystate[SDL_SCANCODE_DOWN] &&
          entity.gridPos.y() < (level_.getSize().h() - 1) &&
          level_.getTileset().canPlayerMoveTo(
            level_.at(entity.gridPos + vec2s { 0, 1 })))
      {
        entity.moving = true;
        entity.destPos = entity.gridPos + vec2s { 0, 1 };
      }

      if (entity.moving)
      {
        entity.movementTween = 0.0;
      }
    }


    // Collision


    // Movement
    if (entity.moving)
    {
      entity.movementTween += entity.speed * dt;

      if (entity.movementTween >= 1.0)
      {
        entity.moving = false;
        entity.gridPos = entity.destPos;
      }
    }

    if (entity.moving)
    {
      entity.pos.x() =
        TILE_SIZE.x() * entity.destPos.x() * entity.movementTween +
        TILE_SIZE.x() * entity.gridPos.x() * (1.0 - entity.movementTween);

      entity.pos.y() =
        TILE_SIZE.y() * entity.destPos.y() * entity.movementTween +
        TILE_SIZE.y() * entity.gridPos.y() * (1.0 - entity.movementTween);
    } else {
      entity.pos = TILE_SIZE * entity.gridPos;
    }
  }
}

Simulation::id_type Simulation::emplaceEntity()
{
  id_type nextId;

  if (!available_.empty())
  {
    nextId = available_.front();
    available_.pop_front();

    entities_.at(nextId) = Entity();
  } else {
    nextId = entities_.size();
    entities_.emplace_back();
  }

  active_.insert(nextId);

  return nextId;
}

void Simulation::deleteEntity(id_type id)
{
  available_.push_back(id);
  active_.erase(id);
}