X-Git-Url: http://git.localhorst.tv/?a=blobdiff_plain;f=src%2Fai%2Fai.cpp;h=db4ae413d8170a9dbc5f7f7056978a0615f6e5ee;hb=c4416bc2a5e446d0ba99cfeb50bb5fab287a1c4e;hp=fd03ebb4fec74e0cf3309f41e9ba44bee6546f1c;hpb=e872614d387c4bfc3afb04bcc7cba3d9b8f3954b;p=blank.git

diff --git a/src/ai/ai.cpp b/src/ai/ai.cpp
index fd03ebb..db4ae41 100644
--- a/src/ai/ai.cpp
+++ b/src/ai/ai.cpp
@@ -1,116 +1,281 @@
-#include "Chaser.hpp"
-#include "Controller.hpp"
-#include "RandomWalk.hpp"
+#include "AIController.hpp"
+#include "ChaseState.hpp"
+#include "FleeState.hpp"
+#include "IdleState.hpp"
+#include "RoamState.hpp"
 
-#include "../model/geometry.hpp"
+#include "../geometry/distance.hpp"
+#include "../geometry/rotation.hpp"
+#include "../rand/GaloisLFSR.hpp"
 #include "../world/Entity.hpp"
 #include "../world/World.hpp"
 #include "../world/WorldCollision.hpp"
 
+#include <cmath>
+#include <limits>
 #include <glm/glm.hpp>
 
 
 namespace blank {
 
-Chaser::Chaser(World &world, Entity &ctrl, Entity &tgt) noexcept
-: Controller(ctrl)
-, world(world)
-, tgt(tgt)
-, chase_speed(0.002f)
-, flee_speed(-0.005f)
-, stop_dist(10)
-, flee_dist(5) {
+namespace {
+
+ChaseState chase;
+FleeState flee;
+IdleState idle;
+RoamState roam;
 
 }
 
-Chaser::~Chaser() {
+AIController::AIController(World &world, Entity &entity)
+: world(world)
+, state(&idle)
+, sight_dist(64.0f)
+, sight_angle(0.707f)
+, think_timer(0.5f)
+, decision_timer(1.0f) {
+	think_timer.Start();
+	state->Enter(*this, entity);
+}
 
+AIController::~AIController() {
+	// ignore this for now
+	// state->Exit(*this, entity);
 }
 
-void Chaser::Update(int dt) {
-	glm::vec3 diff(Target().AbsoluteDifference(Controlled()));
-	float dist = length(diff);
-	glm::vec3 norm_diff(diff / dist);
+void AIController::SetState(const AIState &s, Entity &entity) {
+	state->Exit(*this, entity);
+	state = &s;
+	state->Enter(*this, entity);
+}
+
+void AIController::Update(Entity &e, float dt) {
+	think_timer.Update(dt);
+	decision_timer.Update(dt);
+	state->Update(*this, e, dt);
 
-	bool line_of_sight = true;
-	Ray aim{Target().Position() - diff, norm_diff};
-	WorldCollision coll;
-	if (world.Intersection(aim, glm::mat4(1.0f), Target().ChunkCoords(), coll)) {
-		line_of_sight = coll.depth > dist;
+	if (e.Moving()) {
+		// orient head towards heading
+		glm::vec3 heading(e.Heading());
+		// only half pitch, so we don't crane our neck
+		float tgt_pitch = std::atan(heading.y / length(glm::vec2(heading.x, heading.z))) * 0.5f;
+		// always look straight ahead
+		// maybe look at the pursuit target if there is one
+		float tgt_yaw = 0.0f;
+		e.SetHead(tgt_pitch, tgt_yaw);
+		e.OrientBody(dt);
 	}
+}
 
-	if (!line_of_sight) {
-		Controlled().Velocity(glm::vec3(0.0f));
-	} else if (dist > stop_dist) {
-		Controlled().Velocity(norm_diff * chase_speed);
-	} else if (dist < flee_dist) {
-		Controlled().Velocity(norm_diff * flee_speed);
-	} else {
-		Controlled().Velocity(glm::vec3(0.0f));
+Player *AIController::ClosestVisiblePlayer(const Entity &e) noexcept {
+	Player *target = nullptr;
+	float distance = sight_dist;
+	const glm::ivec3 &reference(e.ChunkCoords());
+	Ray aim(e.Aim(reference));
+	for (Player &p : world.Players()) {
+		const Entity &pe = p.GetEntity();
+
+		// distance test
+		const glm::vec3 diff(pe.AbsoluteDifference(e));
+		float dist = length(diff);
+		if (dist > distance) continue;
+
+		// FOV test, 45° in each direction
+		if (dot(diff / dist, aim.dir) < sight_angle) {
+			continue;
+		}
+
+		// LOS test, assumes all entities are see-through
+		WorldCollision col;
+		if (world.Intersection(aim, reference, col) && col.depth < dist) {
+			continue;
+		}
+
+		// we got a match
+		target = &p;
+		distance = dist;
+	}
+	return target;
+}
+
+bool AIController::LineOfSight(const Entity &from, const Entity &to) const noexcept {
+	const glm::ivec3 &reference(from.ChunkCoords());
+	Ray aim(from.Aim(reference));
+	const glm::vec3 diff(to.AbsoluteDifference(from));
+	float dist = length(diff);
+	if (dist > sight_dist || dot(diff / dist, aim.dir) < sight_angle) {
+		return false;
 	}
+	WorldCollision col;
+	if (world.Intersection(aim, reference, col) && col.depth < dist) {
+		return false;
+	}
+	return true;
+}
+
+// think
+
+bool AIController::MayThink() const noexcept {
+	return think_timer.Hit();
+}
+
+void AIController::SetThinkInterval(float i) noexcept {
+	think_timer = FineTimer(i);
+	think_timer.Start();
+}
+
+// decide
+
+void AIController::CueDecision(
+	float minimum,
+	float variance
+) noexcept {
+	decision_timer = FineTimer(minimum + variance * world.Random().SNorm());
+	decision_timer.Start();
 }
 
+bool AIController::DecisionDue() const noexcept {
+	return decision_timer.HitOnce();
+}
+
+unsigned int AIController::Decide(unsigned int num_choices) noexcept {
+	return world.Random().Next<unsigned int>() % num_choices;
+}
+
+
+// chase
+
+void ChaseState::Enter(AIController &ctrl, Entity &e) const {
+	e.GetSteering()
+		.SetAcceleration(5.0f)
+		.SetSpeed(4.0f)
+		.Enable(Steering::PURSUE_TARGET)
+	;
+}
 
-Controller::Controller(Entity &e) noexcept
-: entity(e) {
+void ChaseState::Update(AIController &ctrl, Entity &e, float dt) const {
+	Steering &steering = e.GetSteering();
+	// check if target still alive and in sight
+	if (
+		!steering.HasTargetEntity() || // lost
+		steering.GetTargetEntity().Dead() || // dead
+		!ctrl.LineOfSight(e, steering.GetTargetEntity()) // escaped
+	) {
+		steering.ClearTargetEntity();
+		ctrl.SetState(idle, e);
+		return;
+	}
+	// halt if we're close enough, flee if we're too close
+	float dist_sq = length2(e.AbsoluteDifference(steering.GetTargetEntity()));
+	if (dist_sq < 8.0f) {
+		ctrl.SetState(flee, e);
+	} else if (dist_sq < 25.0f) {
+		steering.Enable(Steering::HALT).Disable(Steering::PURSUE_TARGET);
+	} else {
+		steering.Enable(Steering::PURSUE_TARGET).Disable(Steering::HALT);
+	}
+}
 
+void ChaseState::Exit(AIController &ctrl, Entity &e) const {
+	e.GetSteering().Disable(Steering::HALT | Steering::PURSUE_TARGET);
 }
 
-Controller::~Controller() {
+// flee
+
+void FleeState::Enter(AIController &ctrl, Entity &e) const {
+	e.GetSteering()
+		.SetAcceleration(5.0f)
+		.SetSpeed(4.0f)
+		.Enable(Steering::EVADE_TARGET)
+	;
+	ctrl.CueDecision(6.0f, 3.0f);
+}
 
+void FleeState::Update(AIController &ctrl, Entity &e, float dt) const {
+	if (!ctrl.DecisionDue()) return;
+	ctrl.SetState(idle, e);
 }
 
+void FleeState::Exit(AIController &ctrl, Entity &e) const {
+	e.GetSteering().Disable(Steering::EVADE_TARGET);
+}
 
-RandomWalk::RandomWalk(Entity &e) noexcept
-: Controller(e)
-, time_left(0) {
+// idle
 
+void IdleState::Enter(AIController &ctrl, Entity &e) const {
+	e.GetSteering()
+		.SetAcceleration(0.5f)
+		.SetSpeed(0.01f)
+		.Enable(Steering::HALT)
+		.SetWanderParams(1.0f, 1.1f, 1.0f)
+	;
+	ctrl.CueDecision(10.0f, 5.0f);
 }
 
-RandomWalk::~RandomWalk() {
+void IdleState::Update(AIController &ctrl, Entity &e, float dt) const {
+	if (ctrl.MayThink()) {
+		const Player *player = ctrl.ClosestVisiblePlayer(e);
+		if (player) {
+			e.GetSteering().SetTargetEntity(player->GetEntity());
+			ctrl.SetState(chase, e);
+			return;
+		}
+	}
+
+	if (!ctrl.DecisionDue()) return;
+
+	unsigned int d = ctrl.Decide(10);
+	if (d < 2) {
+		// .2 chance to start going
+		ctrl.SetState(roam, e);
+	} else if (d < 5) {
+		// .3 chance of looking around
+		e.GetSteering().Disable(Steering::HALT).Enable(Steering::WANDER);
+	} else {
+		// .5 chance of doing nothing
+		e.GetSteering().Disable(Steering::WANDER).Enable(Steering::HALT);
+	}
+	ctrl.CueDecision(10.0f, 5.0f);
+}
 
+void IdleState::Exit(AIController &ctrl, Entity &e) const {
+	e.GetSteering().Disable(Steering::HALT | Steering::WANDER);
 }
 
-void RandomWalk::Update(int dt) {
-	time_left -= dt;
-	if (time_left > 0) return;
-	time_left += 2500 + (rand() % 5000);
+// roam
+
+void RoamState::Enter(AIController &ctrl, Entity &e) const {
+	e.GetSteering()
+		.SetAcceleration(0.5f)
+		.SetSpeed(1.0f)
+		.SetWanderParams(1.0f, 2.0f, 1.0f)
+		.Enable(Steering::WANDER)
+	;
+	ctrl.CueDecision(10.0f, 5.0f);
+}
 
-	constexpr float move_vel = 0.0005f;
+void RoamState::Update(AIController &ctrl, Entity &e, float dt) const {
+	if (ctrl.MayThink()) {
+		const Player *player = ctrl.ClosestVisiblePlayer(e);
+		if (player) {
+			e.GetSteering().SetTargetEntity(player->GetEntity());
+			ctrl.SetState(chase, e);
+			return;
+		}
+	}
 
-	glm::vec3 new_vel = Controlled().Velocity();
+	if (!ctrl.DecisionDue()) return;
 
-	switch (rand() % 9) {
-		case 0:
-			new_vel.x = -move_vel;
-			break;
-		case 1:
-			new_vel.x = 0.0f;
-			break;
-		case 2:
-			new_vel.x = move_vel;
-			break;
-		case 3:
-			new_vel.y = -move_vel;
-			break;
-		case 4:
-			new_vel.y = 0.0f;
-			break;
-		case 5:
-			new_vel.y = move_vel;
-			break;
-		case 6:
-			new_vel.z = -move_vel;
-			break;
-		case 7:
-			new_vel.z = 0.0f;
-			break;
-		case 8:
-			new_vel.z = move_vel;
-			break;
+	unsigned int d = ctrl.Decide(10);
+	if (d == 0) {
+		// .1 chance of idling
+		ctrl.SetState(idle, e);
 	}
+	ctrl.CueDecision(10.0f, 5.0f);
+}
 
-	Controlled().Velocity(new_vel);
+void RoamState::Exit(AIController &ctrl, Entity &e) const {
+	e.GetSteering().Disable(Steering::WANDER);
 }
 
 }