#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"
namespace {
+ChaseState chase;
+FleeState flee;
IdleState idle;
RoamState roam;
}
-AIController::AIController(GaloisLFSR &rand)
-: random(rand)
+AIController::AIController(World &world, GaloisLFSR &rand)
+: world(world)
+, random(rand)
, state(&idle)
+, sight_dist(64.0f)
+, sight_angle(0.707f)
+, think_timer(0.5f)
, decision_timer(1.0f)
, halted(false)
, halt_speed(1.0f)
+, avoid_obstacles(true)
+, obstacle_box{ glm::vec3(0.0f), glm::vec3(0.0f) }
+, obstacle_transform(1.0f)
+, fleeing(false)
, flee_target(nullptr)
, flee_speed(5.0f)
+, seeking(false)
, seek_target(nullptr)
, seek_speed(5.0f)
+, evading(false)
+, evade_target(nullptr)
+, evade_speed(5.0f)
+, pursuing(false)
+, pursuit_target(nullptr)
+, pursuit_speed(5.0f)
, wandering(false)
, wander_pos(1.0f, 0.0f, 0.0f)
, wander_speed(1.0f)
, wander_dist(2.0f)
, wander_radius(1.5f)
, wander_disp(1.0f) {
+ think_timer.Start();
state->Enter(*this);
}
}
void AIController::Update(Entity &e, float dt) {
+ think_timer.Update(dt);
decision_timer.Update(dt);
state->Update(*this, e, dt);
+ if (avoid_obstacles && e.Moving()) {
+ obstacle_box = e.Bounds();
+ obstacle_box.min.z = -e.Speed();
+ obstacle_box.max.x = 0.0f;
+ // our box is oriented for -Z velocity
+ obstacle_transform = glm::mat4(find_rotation(glm::vec3(0.0f, 0.0f, -1.0f), e.Heading()));
+ // and positioned relative to the entity's chunk
+ obstacle_transform[3] = glm::vec4(e.GetState().pos.block, 1.0f);
+ }
+
if (wandering) {
glm::vec3 displacement(
random.SNorm() * wander_disp,
if (e.Moving()) {
// orient head towards heading
- glm::vec3 heading(Heading(e.GetState()));
- float tgt_pitch = std::atan(heading.y / length(glm::vec2(heading.x, heading.z)));
- float tgt_yaw = std::atan2(-heading.x, -heading.z);
+ 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);
}
}
glm::vec3 AIController::ControlForce(const Entity &entity, const EntityState &state) const {
if (IsHalted()) {
- return Halt(state, halt_speed);
+ return GetHaltForce(entity, state);
}
glm::vec3 force(0.0f);
+ if (IsAvoidingObstacles() && entity.Moving()) {
+ if (MaxOutForce(force, GetObstacleAvoidanceForce(entity, state), entity.MaxControlForce())) {
+ return force;
+ }
+ }
if (IsFleeing()) {
- glm::vec3 diff(GetFleeTarget().GetState().Diff(state));
- if (MaxOutForce(force, TargetVelocity(normalize(diff) * flee_speed, state, 0.5f), entity.MaxControlForce())) {
+ if (MaxOutForce(force, GetFleeForce(entity, state), entity.MaxControlForce())) {
return force;
}
}
if (IsSeeking()) {
- glm::vec3 diff(state.Diff(GetSeekTarget().GetState()));
- if (MaxOutForce(force, TargetVelocity(normalize(diff) * seek_speed, state, 0.5f), entity.MaxControlForce())) {
+ if (MaxOutForce(force, GetSeekForce(entity, state), entity.MaxControlForce())) {
+ return force;
+ }
+ }
+ if (IsEvading()) {
+ if (MaxOutForce(force, GetEvadeForce(entity, state), entity.MaxControlForce())) {
+ return force;
+ }
+ }
+ if (IsPursuing()) {
+ if (MaxOutForce(force, GetPursuitForce(entity, state), entity.MaxControlForce())) {
return force;
}
}
if (IsWandering()) {
- glm::vec3 wander_target(normalize(Heading(state) * wander_dist + wander_pos) * wander_speed);
- if (MaxOutForce(force, TargetVelocity(wander_target, state, 2.0f), entity.MaxControlForce())) {
+ if (MaxOutForce(force, GetWanderForce(entity, state), entity.MaxControlForce())) {
return force;
}
}
return force;
}
-glm::vec3 AIController::Heading(const EntityState &state) noexcept {
- if (dot(state.velocity, state.velocity) > std::numeric_limits<float>::epsilon()) {
- return normalize(state.velocity);
- } else {
- float cp = std::cos(state.pitch);
- return glm::vec3(std::cos(state.yaw) * cp, std::sin(state.yaw) * cp, std::sin(state.pitch));
+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
return random.Next<unsigned int>() % num_choices;
}
-void AIController::EnterHalt(float speed) noexcept {
+// halt
+
+void AIController::EnterHalt() noexcept {
halted = true;
- halt_speed = speed;
}
void AIController::ExitHalt() noexcept {
return halted;
}
-void AIController::StartFleeing(const Entity &e, float speed) noexcept {
- flee_target = &e;
- flee_speed = speed;
+void AIController::SetHaltSpeed(float speed) noexcept {
+ halt_speed = speed;
+}
+
+glm::vec3 AIController::GetHaltForce(const Entity &, const EntityState &state) const noexcept {
+ return Halt(state, halt_speed);
+}
+
+// obstacle avoidance
+
+void AIController::StartAvoidingObstacles() noexcept {
+ avoid_obstacles = true;
+}
+
+void AIController::StopAvoidingObstacles() noexcept {
+ avoid_obstacles = false;
+}
+
+bool AIController::IsAvoidingObstacles() const noexcept {
+ return avoid_obstacles;
+}
+
+namespace {
+
+std::vector<WorldCollision> col;
+
+}
+
+glm::vec3 AIController::GetObstacleAvoidanceForce(const Entity &e, const EntityState &state) const noexcept {
+ if (!e.Moving()) {
+ return glm::vec3(0.0f);
+ }
+ col.clear();
+ if (!world.Intersection(obstacle_box, obstacle_transform, e.ChunkCoords(), col)) {
+ return glm::vec3(0.0f);
+ }
+ // find the nearest block
+ WorldCollision *nearest = nullptr;
+ glm::vec3 difference(0.0f);
+ float distance = std::numeric_limits<float>::infinity();
+ for (WorldCollision &c : col) {
+ // diff points from block to state
+ glm::vec3 diff = state.RelativePosition(c.ChunkPos()) - c.BlockCoords();
+ float dist = length2(diff);
+ if (dist < distance) {
+ nearest = &c;
+ difference = diff;
+ distance = dist;
+ }
+ }
+ if (!nearest) {
+ // intersection test lied to us
+ return glm::vec3(0.0f);
+ }
+ // and steer away from it
+ // to_go is the distance between our position and the
+ // point on the "velocity ray" closest to obstacle
+ float to_go = dot(difference, e.Heading());
+ // point is our future position if we keep going our way
+ glm::vec3 point(e.GetState().pos.block + e.Heading() * to_go);
+ // now steer away in the direction of (point - block)
+ // with a magniture proportional to speed/distance
+ return normalize(point - nearest->BlockCoords()) * (e.Speed() / std::sqrt(distance));
+}
+
+// flee
+
+void AIController::StartFleeing() noexcept {
+ fleeing = true;
}
void AIController::StopFleeing() noexcept {
- flee_target = nullptr;
+ fleeing = false;
+ if (flee_target) {
+ flee_target->UnRef();
+ flee_target = nullptr;
+ }
}
bool AIController::IsFleeing() const noexcept {
- return flee_target;
+ return fleeing && flee_target;
+}
+
+void AIController::SetFleeTarget(Entity &e) noexcept {
+ if (flee_target) {
+ flee_target->UnRef();
+ }
+ flee_target = &e;
+ flee_target->Ref();
+}
+
+void AIController::SetFleeSpeed(float speed) noexcept {
+ flee_speed = speed;
+}
+
+Entity &AIController::GetFleeTarget() noexcept {
+ return *flee_target;
}
const Entity &AIController::GetFleeTarget() const noexcept {
return *flee_target;
}
-void AIController::StartSeeking(const Entity &e, float speed) noexcept {
- seek_target = &e;
- seek_speed = speed;
+glm::vec3 AIController::GetFleeForce(const Entity &, const EntityState &state) const noexcept {
+ return Flee(state, GetFleeTarget().GetState(), flee_speed, 2.0f);
+}
+
+// seek
+
+void AIController::StartSeeking() noexcept {
+ seeking = true;
}
void AIController::StopSeeking() noexcept {
- seek_target = nullptr;
+ seeking = false;
+ if (seek_target) {
+ seek_target->UnRef();
+ seek_target = nullptr;
+ }
}
bool AIController::IsSeeking() const noexcept {
- return seek_target;
+ return seeking && seek_target;
+}
+
+void AIController::SetSeekTarget(Entity &e) noexcept {
+ if (seek_target) {
+ seek_target->UnRef();
+ }
+ seek_target = &e;
+ seek_target->Ref();
+}
+
+void AIController::SetSeekSpeed(float speed) noexcept {
+ seek_speed = speed;
+}
+
+Entity &AIController::GetSeekTarget() noexcept {
+ return *seek_target;
}
const Entity &AIController::GetSeekTarget() const noexcept {
return *seek_target;
}
-void AIController::StartWandering(
+glm::vec3 AIController::GetSeekForce(const Entity &, const EntityState &state) const noexcept {
+ return Seek(state, GetSeekTarget().GetState(), seek_speed, 2.0f);
+}
+
+// evade
+
+void AIController::StartEvading() noexcept {
+ evading = true;
+}
+
+void AIController::StopEvading() noexcept {
+ evading = false;
+ if (evade_target) {
+ evade_target->UnRef();
+ evade_target = nullptr;
+ }
+}
+
+bool AIController::IsEvading() const noexcept {
+ return evading && evade_target;
+}
+
+void AIController::SetEvadeTarget(Entity &e) noexcept {
+ if (evade_target) {
+ evade_target->UnRef();
+ }
+ evade_target = &e;
+ evade_target->Ref();
+}
+
+void AIController::SetEvadeSpeed(float speed) noexcept {
+ evade_speed = speed;
+}
+
+Entity &AIController::GetEvadeTarget() noexcept {
+ return *evade_target;
+}
+
+const Entity &AIController::GetEvadeTarget() const noexcept {
+ return *evade_target;
+}
+
+glm::vec3 AIController::GetEvadeForce(const Entity &, const EntityState &state) const noexcept{
+ glm::vec3 cur_diff(state.Diff(GetEvadeTarget().GetState()));
+ float time_estimate = length(cur_diff) / evade_speed;
+ EntityState pred_state(GetEvadeTarget().GetState());
+ pred_state.pos.block += pred_state.velocity * time_estimate;
+ return Flee(state, pred_state, evade_speed, 2.0f);
+}
+
+// pursuit
+
+void AIController::StartPursuing() noexcept {
+ pursuing = true;
+}
+
+void AIController::StopPursuing() noexcept {
+ pursuing = false;
+ if (pursuit_target) {
+ pursuit_target->UnRef();
+ pursuit_target = nullptr;
+ }
+}
+
+bool AIController::IsPursuing() const noexcept {
+ return pursuing && pursuit_target;
+}
+
+void AIController::SetPursuitTarget(Entity &e) noexcept {
+ if (pursuit_target) {
+ pursuit_target->UnRef();
+ }
+ pursuit_target = &e;
+ pursuit_target->Ref();
+}
+
+void AIController::SetPursuitSpeed(float speed) noexcept {
+ pursuit_speed = speed;
+}
+
+Entity &AIController::GetPursuitTarget() noexcept {
+ return *pursuit_target;
+}
+
+const Entity &AIController::GetPursuitTarget() const noexcept {
+ return *pursuit_target;
+}
+
+glm::vec3 AIController::GetPursuitForce(const Entity &, const EntityState &state) const noexcept {
+ glm::vec3 cur_diff(state.Diff(GetPursuitTarget().GetState()));
+ float time_estimate = length(cur_diff) / pursuit_speed;
+ EntityState pred_state(GetPursuitTarget().GetState());
+ pred_state.pos.block += pred_state.velocity * time_estimate;
+ return Seek(state, pred_state, pursuit_speed, 2.0f);
+}
+
+// wander
+
+void AIController::StartWandering() noexcept {
+ wandering = true;
+}
+
+void AIController::StopWandering() noexcept {
+ wandering = false;
+}
+
+bool AIController::IsWandering() const noexcept {
+ return wandering;
+}
+
+void AIController::SetWanderParams(
float speed,
float distance,
float radius,
float displacement
) noexcept {
- wandering = true;
wander_speed = speed;
wander_dist = distance;
wander_radius = radius;
wander_disp = displacement;
}
-void AIController::StopWandering() noexcept {
- wandering = false;
+glm::vec3 AIController::GetWanderForce(const Entity &e, const EntityState &state) const noexcept {
+ glm::vec3 wander_target(normalize(e.Heading() * wander_dist + wander_pos) * wander_speed);
+ return TargetVelocity(wander_target, state, 0.5f);
}
-bool AIController::IsWandering() const noexcept {
- return wandering;
+
+// chase
+
+void ChaseState::Enter(AIController &ctrl) const {
+ ctrl.SetHaltSpeed(2.0f);
+ ctrl.SetPursuitSpeed(4.0f);
+ ctrl.StartPursuing();
+}
+
+void ChaseState::Update(AIController &ctrl, Entity &e, float dt) const {
+ // check if target still alive and in sight
+ if (ctrl.GetPursuitTarget().Dead()) {
+ ctrl.SetState(idle);
+ return;
+ }
+ if (!ctrl.LineOfSight(e, ctrl.GetPursuitTarget())) {
+ ctrl.SetState(idle);
+ return;
+ }
+ // halt if we're close enough, flee if we're too close
+ float dist_sq = length2(e.AbsoluteDifference(ctrl.GetPursuitTarget()));
+ if (dist_sq < 8.0f) {
+ ctrl.SetFleeTarget(ctrl.GetPursuitTarget());
+ ctrl.SetState(flee);
+ } else if (dist_sq < 25.0f) {
+ ctrl.EnterHalt();
+ } else {
+ ctrl.ExitHalt();
+ }
+}
+
+void ChaseState::Exit(AIController &ctrl) const {
+ ctrl.StopPursuing();
+ ctrl.ExitHalt();
}
+// flee
+
+void FleeState::Enter(AIController &ctrl) const {
+ ctrl.CueDecision(6.0f, 3.0f);
+ ctrl.SetFleeSpeed(4.0f);
+ ctrl.StartFleeing();
+}
+
+void FleeState::Update(AIController &ctrl, Entity &e, float dt) const {
+ if (!ctrl.DecisionDue()) return;
+ ctrl.SetState(idle);
+}
+
+void FleeState::Exit(AIController &ctrl) const {
+ ctrl.StopFleeing();
+}
+
+// idle
void IdleState::Enter(AIController &ctrl) const {
- ctrl.EnterHalt(2.0f);
- ctrl.StartWandering(0.001f, 1.1f);
+ ctrl.SetHaltSpeed(0.5f);
+ ctrl.EnterHalt();
+ ctrl.SetWanderParams(0.001f, 1.1f);
ctrl.CueDecision(10.0f, 5.0f);
}
void IdleState::Update(AIController &ctrl, Entity &e, float dt) const {
- // TODO: check for players
+ if (ctrl.MayThink()) {
+ const Player *player = ctrl.ClosestVisiblePlayer(e);
+ if (player) {
+ ctrl.SetPursuitTarget(player->GetEntity());
+ ctrl.SetState(chase);
+ return;
+ }
+ }
+
if (!ctrl.DecisionDue()) return;
unsigned int d = ctrl.Decide(10);
- if (d == 0) {
- // .1 chance to start going
+ if (d < 2) {
+ // .2 chance to start going
ctrl.SetState(roam);
- } else if (d < 3) {
- // .2 chance of looking around
+ } else if (d < 5) {
+ // .3 chance of looking around
ctrl.ExitHalt();
+ ctrl.StartWandering();
} else {
- ctrl.EnterHalt(2.0f);
+ // .5 chance of doing nothing
+ ctrl.StopWandering();
+ ctrl.EnterHalt();
}
ctrl.CueDecision(10.0f, 5.0f);
}
ctrl.StopWandering();
}
+// roam
+
void RoamState::Enter(AIController &ctrl) const {
- ctrl.StartWandering(1.0f);
+ ctrl.SetWanderParams(1.0f);
+ ctrl.StartWandering();
ctrl.CueDecision(10.0f, 5.0f);
}
void RoamState::Update(AIController &ctrl, Entity &e, float dt) const {
- // TODO: check for players
+ if (ctrl.MayThink()) {
+ const Player *player = ctrl.ClosestVisiblePlayer(e);
+ if (player) {
+ ctrl.SetPursuitTarget(player->GetEntity());
+ ctrl.SetState(chase);
+ return;
+ }
+ }
+
if (!ctrl.DecisionDue()) return;
unsigned int d = ctrl.Decide(10);