monster_ai_system.rs 2.8 KB

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  1. use crate::{Map, Monster, Position, RunState, Seek, Viewshed, WantsToMelee};
  2. use rltk::Point;
  3. use specs::prelude::*;
  4. pub struct MonsterAI;
  5. impl<'a> System<'a> for MonsterAI {
  6. #[allow(clippy::type_complexity)]
  7. type SystemData = (
  8. ReadExpect<'a, Point>,
  9. ReadExpect<'a, Entity>,
  10. ReadExpect<'a, RunState>,
  11. Entities<'a>,
  12. ReadStorage<'a, Viewshed>,
  13. ReadStorage<'a, Monster>,
  14. WriteStorage<'a, Position>,
  15. WriteStorage<'a, WantsToMelee>,
  16. WriteStorage<'a, Seek>,
  17. );
  18. fn run(&mut self, data: Self::SystemData) {
  19. let (
  20. player_pos,
  21. player_entity,
  22. runstate,
  23. entities,
  24. viewshed,
  25. monster,
  26. position,
  27. mut wants_to_melee,
  28. mut seek,
  29. ) = data;
  30. if *runstate != RunState::MonsterTurn {
  31. return;
  32. }
  33. for (entity, viewshed, _monster, pos) in (&entities, &viewshed, &monster, &position).join()
  34. {
  35. let distance =
  36. rltk::DistanceAlg::Pythagoras.distance2d(Point::new(pos.x, pos.y), *player_pos);
  37. if distance < 1.5 {
  38. wants_to_melee
  39. .insert(
  40. entity,
  41. WantsToMelee {
  42. target: *player_entity,
  43. },
  44. )
  45. .expect("Unable to insert attack");
  46. } else if viewshed.visible_tiles.contains(&*player_pos) {
  47. seek.insert(
  48. entity,
  49. Seek {
  50. tgt_x: player_pos.x,
  51. tgt_y: player_pos.y,
  52. },
  53. )
  54. .expect("Unable to insert seek");
  55. }
  56. }
  57. }
  58. }
  59. pub struct MoveFollow;
  60. impl<'a> System<'a> for MoveFollow {
  61. type SystemData = (
  62. WriteExpect<'a, Map>,
  63. WriteStorage<'a, Position>,
  64. WriteStorage<'a, Seek>,
  65. WriteStorage<'a, Viewshed>,
  66. );
  67. fn run(&mut self, (mut map, mut position, mut seek, mut viewshed): Self::SystemData) {
  68. for (mut pos, seek, mut view) in (&mut position, &seek, &mut viewshed).join() {
  69. let path = rltk::a_star_search(
  70. map.xy_idx(pos.x, pos.y) as i32,
  71. map.xy_idx(seek.tgt_x, seek.tgt_y) as i32,
  72. &mut *map,
  73. );
  74. if path.success && path.steps.len() > 1 {
  75. let mut idx = map.xy_idx(pos.x, pos.y);
  76. map.blocked[idx] = false;
  77. pos.x = path.steps[1] % map.width;
  78. pos.y = path.steps[1] / map.width;
  79. idx = map.xy_idx(pos.x, pos.y);
  80. map.blocked[idx] = true;
  81. view.dirty = true;
  82. }
  83. }
  84. seek.clear();
  85. }
  86. }