src/ai/ai.cpp

   1 #include "Chaser.hpp"
   2 #include "Controller.hpp"
   3 #include "RandomWalk.hpp"
   4
   5 #include "../model/geometry.hpp"
   6 #include "../world/Entity.hpp"
   7 #include "../world/World.hpp"
   8 #include "../world/WorldCollision.hpp"
   9
  10 #include <glm/glm.hpp>
  11
  12
  13 namespace blank {
  14
  15 Chaser::Chaser(World &world, Entity &ctrl, Entity &tgt) noexcept
  16 : Controller(ctrl)
  17 , world(world)
  18 , tgt(tgt)
  19 , chase_speed(0.002f)
  20 , flee_speed(-0.005f)
  21 , stop_dist(10)
  22 , flee_dist(5) {
  23         tgt.Ref();
  24 }
  25
  26 Chaser::~Chaser() {
  27         tgt.UnRef();
  28 }
  29
  30 void Chaser::Update(int dt) {
  31         glm::vec3 diff(Target().AbsoluteDifference(Controlled()));
  32         float dist = length(diff);
  33         if (dist < std::numeric_limits<float>::epsilon()) {
  34                 Controlled().Velocity(glm::vec3(0.0f));
  35                 return;
  36         }
  37         glm::vec3 norm_diff(diff / dist);
  38
  39         bool line_of_sight = true;
  40         Ray aim{Target().Position() - diff, norm_diff};
  41         WorldCollision coll;
  42         if (world.Intersection(aim, glm::mat4(1.0f), Target().ChunkCoords(), coll)) {
  43                 line_of_sight = coll.depth > dist;
  44         }
  45
  46         if (!line_of_sight) {
  47                 Controlled().Velocity(glm::vec3(0.0f));
  48         } else if (dist > stop_dist) {
  49                 Controlled().Velocity(norm_diff * chase_speed);
  50         } else if (dist < flee_dist) {
  51                 Controlled().Velocity(norm_diff * flee_speed);
  52         } else {
  53                 Controlled().Velocity(glm::vec3(0.0f));
  54         }
  55 }
  56
  57
  58 Controller::Controller(Entity &e) noexcept
  59 : entity(e) {
  60         entity.Ref();
  61 }
  62
  63 Controller::~Controller() {
  64         entity.UnRef();
  65 }
  66
  67
  68 RandomWalk::RandomWalk(Entity &e, std::uint64_t seed) noexcept
  69 : Controller(e)
  70 , random(seed)
  71 , time_left(0) {
  72
  73 }
  74
  75 RandomWalk::~RandomWalk() {
  76
  77 }
  78
  79 void RandomWalk::Update(int dt) {
  80         time_left -= dt;
  81         if (time_left > 0) return;
  82         time_left += 2500 + (random.Next<unsigned short>() % 5000);
  83
  84         constexpr float move_vel = 0.0005f;
  85
  86         glm::vec3 new_vel = Controlled().Velocity();
  87
  88         switch (random.Next<unsigned char>() % 9) {
  89                 case 0:
  90                         new_vel.x = -move_vel;
  91                         break;
  92                 case 1:
  93                         new_vel.x = 0.0f;
  94                         break;
  95                 case 2:
  96                         new_vel.x = move_vel;
  97                         break;
  98                 case 3:
  99                         new_vel.y = -move_vel;
 100                         break;
 101                 case 4:
 102                         new_vel.y = 0.0f;
 103                         break;
 104                 case 5:
 105                         new_vel.y = move_vel;
 106                         break;
 107                 case 6:
 108                         new_vel.z = -move_vel;
 109                         break;
 110                 case 7:
 111                         new_vel.z = 0.0f;
 112                         break;
 113                 case 8:
 114                         new_vel.z = move_vel;
 115                         break;
 116         }
 117
 118         Controlled().Velocity(new_vel);
 119 }
 120
 121 }