#include "Entity.hpp"
+#include "EntityCollision.hpp"
#include "EntityController.hpp"
#include "EntityDerivative.hpp"
#include "EntityState.hpp"
#include "EntityCollision.hpp"
#include "WorldCollision.hpp"
#include "../app/Assets.hpp"
+#include "../geometry/const.hpp"
+#include "../geometry/distance.hpp"
+#include "../geometry/rotation.hpp"
#include "../graphics/Format.hpp"
#include "../graphics/Viewport.hpp"
#include <limits>
#include <glm/gtx/euler_angles.hpp>
#include <glm/gtx/io.hpp>
+#include <glm/gtx/projection.hpp>
#include <glm/gtx/quaternion.hpp>
+#include <glm/gtx/rotate_vector.hpp>
#include <glm/gtx/transform.hpp>
namespace blank {
+namespace {
+
+/// used as a buffer for merging collisions
+std::vector<WorldCollision> col;
+
+}
+
Entity::Entity() noexcept
-: ctrl(nullptr)
+: steering(*this)
+, ctrl(nullptr)
, model()
, id(-1)
, name("anonymous")
, bounds()
+, radius(0.0f)
, state()
, heading(0.0f, 0.0f, -1.0f)
, max_vel(5.0f)
}
Entity::Entity(const Entity &other) noexcept
-: ctrl(other.ctrl)
+: steering(*this)
+, ctrl(other.ctrl)
, model(other.model)
, id(-1)
, name(other.name)
}
glm::vec3 Entity::ControlForce(const EntityState &s) const noexcept {
- if (HasController()) {
- return GetController().ControlForce(*this, s);
- } else {
- return -s.velocity;
- }
+ return steering.Force(s);
}
void Entity::Position(const glm::ivec3 &c, const glm::vec3 &b) noexcept {
- state.chunk_pos = c;
- state.block_pos = b;
+ state.pos.chunk = c;
+ state.pos.block = b;
}
void Entity::Position(const glm::vec3 &pos) noexcept {
- state.block_pos = pos;
+ state.pos.block = pos;
state.AdjustPosition();
}
void Entity::SetHead(float p, float y) noexcept {
state.pitch = p;
state.yaw = y;
- // TODO: I feel like this could be delayed
- UpdateModel();
}
glm::mat4 Entity::Transform(const glm::ivec3 &reference) const noexcept {
- return glm::translate(glm::vec3((state.chunk_pos - reference) * Chunk::Extent())) * model_transform;
+ return glm::translate(glm::vec3((state.pos.chunk - reference) * ExactLocation::Extent())) * model_transform;
}
glm::mat4 Entity::ViewTransform(const glm::ivec3 &reference) const noexcept {
return Transform(reference) * view_transform;
}
-Ray Entity::Aim(const Chunk::Pos &chunk_offset) const noexcept {
+Ray Entity::Aim(const ExactLocation::Coarse &chunk_offset) const noexcept {
glm::mat4 transform = ViewTransform(chunk_offset);
return Ray{ glm::vec3(transform[3]), -glm::vec3(transform[2]) };
}
-void Entity::UpdateModel() noexcept {
- state.AdjustHeading();
- state.orient = glm::quat(glm::vec3(0.0f, state.yaw, 0.0f));
- if (model) {
- model.EyesState().orientation = glm::quat(glm::vec3(state.pitch, 0.0f, 0.0f));
- }
-}
-
-void Entity::Update(float dt) {
- UpdateTransforms();
- UpdateHeading();
+void Entity::Update(World &world, float dt) {
if (HasController()) {
GetController().Update(*this, dt);
}
+ steering.Update(world, dt);
+ UpdatePhysics(world, dt);
+ UpdateTransforms();
+ UpdateHeading();
+ UpdateModel(dt);
+}
+
+void Entity::UpdatePhysics(World &world, float dt) {
+ EntityState s(state);
+
+ EntityDerivative a(CalculateStep(world, s, 0.0f, EntityDerivative()));
+ EntityDerivative b(CalculateStep(world, s, dt * 0.5f, a));
+ EntityDerivative c(CalculateStep(world, s, dt * 0.5f, b));
+ EntityDerivative d(CalculateStep(world, s, dt, c));
+
+ EntityDerivative f;
+ constexpr float sixth = 1.0f / 6.0f;
+ f.position = sixth * (a.position + 2.0f * (b.position + c.position) + d.position);
+ f.velocity = sixth * (a.velocity + 2.0f * (b.velocity + c.velocity) + d.velocity);
+
+ s.pos.block += f.position * dt;
+ s.velocity += f.velocity * dt;
+ limit(s.velocity, max_vel);
+ world.ResolveWorldCollision(*this, s);
+ s.AdjustPosition();
+
+ SetState(s);
+}
+
+EntityDerivative Entity::CalculateStep(
+ World &world,
+ const EntityState &cur,
+ float dt,
+ const EntityDerivative &delta
+) const {
+ EntityState next(cur);
+ next.pos.block += delta.position * dt;
+ next.velocity += delta.velocity * dt;
+ limit(next.velocity, max_vel);
+ world.ResolveWorldCollision(*this, next);
+ next.AdjustPosition();
+
+ EntityDerivative out;
+ out.position = next.velocity;
+ out.velocity = ControlForce(next) + world.GravityAt(next.pos); // by mass = 1kg
+ return out;
}
+
void Entity::UpdateTransforms() noexcept {
// model transform is the one given by current state
- model_transform = state.Transform(state.chunk_pos);
+ model_transform = state.Transform(state.pos.chunk);
// view transform is either the model's eyes transform or,
// should the entity have no model, the pitch (yaw already is
// in model transform)
if (model) {
view_transform = model.EyesTransform();
} else {
- view_transform = glm::eulerAngleX(state.pitch);
+ view_transform = toMat4(glm::quat(glm::vec3(state.pitch, state.yaw, 0.0f)));
}
}
}
}
+void Entity::UpdateModel(float dt) noexcept {
+ // first, sanitize the pitch and yaw fields of state (our input)
+ // those indicate the head orientation in the entity's local cosystem
+ state.AdjustHeading();
+ // TODO: this flickers horrible and also shouldn't be based on velocity, but on control force
+ //OrientBody(dt);
+ OrientHead(dt);
+}
-EntityController::~EntityController() {
+void Entity::OrientBody(float dt) noexcept {
+ // maximum body rotation per second (due to velocity orientation) (90°)
+ constexpr float max_body_turn_per_second = PI_0p5;
+ const float max_body_turn = max_body_turn_per_second * dt;
+ // minimum speed to apply body correction
+ constexpr float min_speed = 0.0625f;
+ // use local Y as up
+ const glm::vec3 up(model_transform[1]);
+ if (speed > min_speed) {
+ // check if our orientation and velocity are aligned
+ const glm::vec3 forward(-model_transform[2]);
+ // facing is local -Z rotated about local Y by yaw and transformed into world space
+ const glm::vec3 facing(normalize(glm::vec3(glm::vec4(rotateY(glm::vec3(0.0f, 0.0f, -1.0f), state.yaw), 0.0f) * transpose(model_transform))));
+ // only adjust if velocity isn't almost parallel to up
+ float vel_dot_up = dot(Velocity(), up);
+ if (std::abs(1.0f - std::abs(vel_dot_up)) > std::numeric_limits<float>::epsilon()) {
+ // get direction of velocity projected onto model plane
+ glm::vec3 direction(normalize(Velocity() - (Velocity() * vel_dot_up)));
+ // if velocity points away from our facing (with a little bias), flip it around
+ // (the entity is "walking backwards")
+ if (dot(facing, direction) < -0.1f) {
+ direction = -direction;
+ }
+ // calculate the difference between forward and direction
+ const float absolute_difference = std::acos(dot(forward, direction));
+ // if direction is clockwise with respect to up vector, invert the angle
+ const float relative_difference = dot(cross(forward, direction), up) < 0.0f
+ ? -absolute_difference
+ : absolute_difference;
+ // only correct by half the difference max
+ const float correction = glm::clamp(relative_difference * 0.5f, -max_body_turn, max_body_turn);
+ if (ID() == 1) {
+ std::cout << "orientation before: " << state.orient << std::endl;
+ std::cout << "up: " << up << std::endl;
+ std::cout << "forward: " << forward << std::endl;
+ std::cout << "facing: " << facing << std::endl;
+ std::cout << "direction: " << direction << std::endl;
+ std::cout << "difference: " << glm::degrees(relative_difference) << "°" << std::endl;
+ std::cout << "correction: " << glm::degrees(correction) << "°" << std::endl;
+ std::cout << std::endl;
+ }
+ // now rotate body by correction and head by -correction
+ state.orient = rotate(state.orient, correction, up);
+ state.yaw -= correction;
+ }
+ }
+}
+void Entity::OrientHead(float dt) noexcept {
+ // maximum yaw of head (60°)
+ constexpr float max_head_yaw = PI / 3.0f;
+ // use local Y as up
+ const glm::vec3 up(model_transform[1]);
+ // if yaw is bigger than max, rotate the body to accomodate
+ if (std::abs(state.yaw) > max_head_yaw) {
+ float deviation = state.yaw < 0.0f ? state.yaw + max_head_yaw : state.yaw - max_head_yaw;
+ // rotate the entity by deviation about local Y
+ state.orient = rotate(state.orient, deviation, up);
+ // and remove from head yaw
+ state.yaw -= deviation;
+ // shouldn't be necessary if max_head_yaw is < PI, but just to be sure :p
+ state.AdjustHeading();
+ }
+ // update model if any
+ if (model) {
+ model.EyesState().orientation = glm::quat(glm::vec3(state.pitch, state.yaw, 0.0f));
+ }
}
-bool EntityController::MaxOutForce(
- glm::vec3 &out,
- const glm::vec3 &add,
- float max
-) noexcept {
- if (iszero(add) || any(isnan(add))) {
- return false;
+
+EntityCollision::EntityCollision(Entity *e, float d, const glm::vec3 &n)
+: depth(d)
+, normal(n)
+, entity(e) {
+ if (entity) {
+ entity->Ref();
}
- float current = iszero(out) ? 0.0f : length(out);
- float remain = max - current;
- if (remain <= 0.0f) {
- return true;
+}
+
+EntityCollision::~EntityCollision() {
+ if (entity) {
+ entity->UnRef();
}
- float additional = length(add);
- if (additional > remain) {
- out += normalize(add) * remain;
- return true;
- } else {
- out += add;
- return false;
+}
+
+EntityCollision::EntityCollision(const EntityCollision &other)
+: depth(other.depth)
+, normal(other.normal)
+, entity(other.entity) {
+ if (entity) {
+ entity->Ref();
+ }
+}
+
+EntityCollision &EntityCollision::operator =(const EntityCollision &other) {
+ if (entity) {
+ entity->UnRef();
+ }
+ depth = other.depth;
+ normal = other.normal;
+ entity = other.entity;
+ if (entity) {
+ entity->Ref();
}
+ return *this;
+}
+
+
+EntityController::~EntityController() {
+
}
EntityState::EntityState()
-: chunk_pos(0)
-, block_pos(0.0f)
+: pos()
, velocity(0.0f)
, orient(1.0f, 0.0f, 0.0f, 0.0f)
, pitch(0.0f)
}
void EntityState::AdjustPosition() noexcept {
- while (block_pos.x >= Chunk::width) {
- block_pos.x -= Chunk::width;
- ++chunk_pos.x;
- }
- while (block_pos.x < 0) {
- block_pos.x += Chunk::width;
- --chunk_pos.x;
- }
- while (block_pos.y >= Chunk::height) {
- block_pos.y -= Chunk::height;
- ++chunk_pos.y;
- }
- while (block_pos.y < 0) {
- block_pos.y += Chunk::height;
- --chunk_pos.y;
- }
- while (block_pos.z >= Chunk::depth) {
- block_pos.z -= Chunk::depth;
- ++chunk_pos.z;
- }
- while (block_pos.z < 0) {
- block_pos.z += Chunk::depth;
- --chunk_pos.z;
- }
+ pos.Correct();
}
void EntityState::AdjustHeading() noexcept {
- glm::clamp(pitch, -PI_0p5, PI_0p5);
+ pitch = glm::clamp(pitch, -PI_0p5, PI_0p5);
while (yaw > PI) {
yaw -= PI_2p0;
}
}
+Steering::Steering(const Entity &e)
+: entity(e)
+, target_entity(nullptr)
+, target_velocity(0.0f)
+, accel(1.0f)
+, speed(entity.MaxVelocity())
+, wander_radius(1.0f)
+, wander_dist(2.0f)
+, wander_disp(1.0f)
+, wander_pos(1.0f, 0.0f, 0.0f)
+, obstacle_dir(0.0f)
+, enabled(0) {
+
+}
+
+Steering::~Steering() {
+ ClearTargetEntity();
+}
+
+Steering &Steering::SetTargetEntity(Entity &e) noexcept {
+ ClearTargetEntity();
+ target_entity = &e;
+ e.Ref();
+ return *this;
+}
+
+Steering &Steering::ClearTargetEntity() noexcept {
+ if (target_entity) {
+ target_entity->UnRef();
+ target_entity = nullptr;
+ }
+ return *this;
+}
+
+void Steering::Update(World &world, float dt) {
+ if (AnyEnabled(WANDER)) {
+ UpdateWander(world, dt);
+ }
+ if (AnyEnabled(OBSTACLE_AVOIDANCE)) {
+ UpdateObstacle(world);
+ }
+}
+
+void Steering::UpdateWander(World &world, float dt) {
+ glm::vec3 displacement(
+ world.Random().SNorm() * wander_disp,
+ world.Random().SNorm() * wander_disp,
+ world.Random().SNorm() * wander_disp
+ );
+ if (!iszero(displacement)) {
+ wander_pos = normalize(wander_pos + displacement * dt) * wander_radius;
+ }
+}
+
+void Steering::UpdateObstacle(World &world) {
+ if (!entity.Moving()) {
+ obstacle_dir = glm::vec3(0.0f);
+ return;
+ }
+ AABB box(entity.Bounds());
+ box.min.z = -entity.Speed();
+ box.max.z = 0.0f;
+ glm::mat4 transform(find_rotation(glm::vec3(0.0f, 0.0f, -1.0f), entity.Heading()));
+ transform[3] = glm::vec4(entity.Position(), 1.0f);
+ // check if that box intersects with any blocks
+ col.clear();
+ if (!world.Intersection(box, transform, entity.ChunkCoords(), col)) {
+ obstacle_dir = glm::vec3(0.0f);
+ return;
+ }
+ // if so, pick the nearest collision
+ const WorldCollision *nearest = nullptr;
+ glm::vec3 difference(0.0f);
+ float distance = std::numeric_limits<float>::infinity();
+ for (const WorldCollision &c : col) {
+ // diff points from block to state
+ glm::vec3 diff = entity.GetState().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
+ obstacle_dir = glm::vec3(0.0f);
+ return;
+ }
+ // and try to avoid it
+ float to_go = dot(difference, entity.Heading());
+ glm::vec3 point(entity.Position() + entity.Heading() * to_go);
+ obstacle_dir = normalize(point - nearest->BlockCoords()) * (entity.Speed() / std::sqrt(distance));
+}
+
+glm::vec3 Steering::Force(const EntityState &state) const noexcept {
+ glm::vec3 force(0.0f);
+ if (!enabled) {
+ return force;
+ }
+ const float max = entity.MaxControlForce();
+ if (AnyEnabled(HALT)) {
+ if (SumForce(force, Halt(state), max)) {
+ return force;
+ }
+ }
+ if (AnyEnabled(TARGET_VELOCITY)) {
+ if (SumForce(force, TargetVelocity(state, target_velocity), max)) {
+ return force;
+ }
+ }
+ if (AnyEnabled(OBSTACLE_AVOIDANCE)) {
+ if (SumForce(force, ObstacleAvoidance(state), max)) {
+ return force;
+ }
+ }
+ if (AnyEnabled(EVADE_TARGET)) {
+ if (HasTargetEntity()) {
+ if (SumForce(force, Evade(state, GetTargetEntity()), max)) {
+ return force;
+ }
+ } else {
+ std::cout << "Steering: evade enabled, but target entity not set" << std::endl;
+ }
+ }
+ if (AnyEnabled(PURSUE_TARGET)) {
+ if (HasTargetEntity()) {
+ if (SumForce(force, Pursuit(state, GetTargetEntity()), max)) {
+ return force;
+ }
+ } else {
+ std::cout << "Steering: pursuit enabled, but target entity not set" << std::endl;
+ }
+ }
+ if (AnyEnabled(WANDER)) {
+ if (SumForce(force, Wander(state), max)) {
+ return force;
+ }
+ }
+ return force;
+}
+
+bool Steering::SumForce(glm::vec3 &out, const glm::vec3 &in, float max) noexcept {
+ if (iszero(in) || any(isnan(in))) {
+ return false;
+ }
+ float current = iszero(out) ? 0.0f : length(out);
+ float remain = max - current;
+ if (remain <= 0.0f) {
+ return true;
+ }
+ float additional = length(in);
+ if (additional > remain) {
+ out += normalize(in) * remain;
+ return true;
+ } else {
+ out += in;
+ return false;
+ }
+}
+
+glm::vec3 Steering::Halt(const EntityState &state) const noexcept {
+ return state.velocity * -accel;
+}
+
+glm::vec3 Steering::TargetVelocity(const EntityState &state, const glm::vec3 &vel) const noexcept {
+ return (vel - state.velocity) * accel;
+}
+
+glm::vec3 Steering::Seek(const EntityState &state, const ExactLocation &loc) const noexcept {
+ const glm::vec3 diff(loc.Difference(state.pos).Absolute());
+ if (iszero(diff)) {
+ return glm::vec3(0.0f);
+ } else {
+ return TargetVelocity(state, normalize(diff) * speed);
+ }
+}
+
+glm::vec3 Steering::Flee(const EntityState &state, const ExactLocation &loc) const noexcept {
+ const glm::vec3 diff(state.pos.Difference(loc).Absolute());
+ if (iszero(diff)) {
+ return glm::vec3(0.0f);
+ } else {
+ return TargetVelocity(state, normalize(diff) * speed);
+ }
+}
+
+glm::vec3 Steering::Arrive(const EntityState &state, const ExactLocation &loc) const noexcept {
+ const glm::vec3 diff(loc.Difference(state.pos).Absolute());
+ const float dist = length(diff);
+ if (dist < std::numeric_limits<float>::epsilon()) {
+ return glm::vec3(0.0f);
+ } else {
+ const float att_speed = std::min(dist * accel, speed);
+ return TargetVelocity(state, diff * att_speed / dist);
+ }
+}
+
+glm::vec3 Steering::Pursuit(const EntityState &state, const Entity &other) const noexcept {
+ const glm::vec3 diff(state.Diff(other.GetState()));
+ if (iszero(diff)) {
+ return TargetVelocity(state, other.Velocity());
+ } else {
+ const float time_estimate = length(diff) / speed;
+ ExactLocation prediction(other.ChunkCoords(), other.Position() + (other.Velocity() * time_estimate));
+ return Seek(state, prediction);
+ }
+}
+
+glm::vec3 Steering::Evade(const EntityState &state, const Entity &other) const noexcept {
+ const glm::vec3 diff(state.Diff(other.GetState()));
+ if (iszero(diff)) {
+ return TargetVelocity(state, -other.Velocity());
+ } else {
+ const float time_estimate = length(diff) / speed;
+ ExactLocation prediction(other.ChunkCoords(), other.Position() + (other.Velocity() * time_estimate));
+ return Flee(state, prediction);
+ }
+}
+
+glm::vec3 Steering::Wander(const EntityState &state) const noexcept {
+ return TargetVelocity(state, normalize(entity.Heading() * wander_dist + wander_pos) * speed);
+}
+
+glm::vec3 Steering::ObstacleAvoidance(const EntityState &state) const noexcept {
+ return obstacle_dir;
+}
+
+
World::World(const BlockTypeRegistry &types, const Config &config)
: config(config)
, block_type(types)
, chunks(types)
, players()
, entities()
+, rng(
+#ifdef BLANK_PROFILING
+0
+#else
+std::time(nullptr)
+#endif
+)
, light_direction(config.light_direction)
, fog_density(config.fog_density) {
-
+ for (int i = 0; i < 4; ++i) {
+ rng.Next<int>();
+ }
}
World::~World() {
-
+ for (Entity &e : entities) {
+ e.Kill();
+ }
+ std::size_t removed = 0;
+ do {
+ removed = 0;
+ for (auto e = entities.begin(), end = entities.end(); e != end; ++e) {
+ if (e->CanRemove()) {
+ e = RemoveEntity(e);
+ end = entities.end();
+ ++removed;
+ }
+ }
+ } while (removed > 0 && !entities.empty());
}
bool World::Intersection(
const Ray &ray,
- const glm::mat4 &M,
- const Chunk::Pos &reference,
+ const ExactLocation::Coarse &reference,
WorldCollision &coll
) {
candidates.clear();
for (Chunk &cur_chunk : chunks) {
float cur_dist;
- if (cur_chunk.Intersection(ray, M * cur_chunk.Transform(reference), cur_dist)) {
+ if (cur_chunk.Intersection(ray, reference, cur_dist)) {
candidates.push_back({ &cur_chunk, cur_dist });
}
}
for (Candidate &cand : candidates) {
if (cand.dist > coll.depth) continue;
WorldCollision cur_coll;
- if (cand.chunk->Intersection(ray, M * cand.chunk->Transform(reference), cur_coll)) {
+ if (cand.chunk->Intersection(ray, reference, cur_coll)) {
if (cur_coll.depth < coll.depth) {
coll = cur_coll;
}
bool World::Intersection(
const Ray &ray,
- const glm::mat4 &M,
const Entity &reference,
EntityCollision &coll
) {
- coll.entity = nullptr;
- coll.depth = std::numeric_limits<float>::infinity();
+ coll = EntityCollision(nullptr, std::numeric_limits<float>::infinity(), glm::vec3(0.0f));
for (Entity &cur_entity : entities) {
if (&cur_entity == &reference) {
continue;
}
float cur_dist;
glm::vec3 cur_normal;
- if (blank::Intersection(ray, cur_entity.Bounds(), M * cur_entity.Transform(reference.ChunkCoords()), &cur_dist, &cur_normal)) {
+ if (blank::Intersection(ray, cur_entity.Bounds(), cur_entity.Transform(reference.ChunkCoords()), &cur_dist, &cur_normal)) {
// TODO: fine grained check goes here? maybe?
if (cur_dist < coll.depth) {
- coll.entity = &cur_entity;
- coll.depth = cur_dist;
- coll.normal = cur_normal;
+ coll = EntityCollision(&cur_entity, cur_dist, cur_normal);
}
}
}
- return coll.entity;
+ return coll;
}
bool World::Intersection(const Entity &e, const EntityState &s, std::vector<WorldCollision> &col) {
- AABB box = e.Bounds();
- Chunk::Pos reference = s.chunk_pos;
+ glm::ivec3 reference = s.pos.chunk;
glm::mat4 M = s.Transform(reference);
- return Intersection(box, M, reference, col);
+
+ ExactLocation::Coarse begin(reference - 1);
+ ExactLocation::Coarse end(reference + 2);
+
+ bool any = false;
+ for (ExactLocation::Coarse pos(begin); pos.z < end.y; ++pos.z) {
+ for (pos.y = begin.y; pos.y < end.y; ++pos.y) {
+ for (pos.x = begin.x; pos.x < end.x; ++pos.x) {
+ Chunk *chunk = chunks.Get(pos);
+ if (chunk && chunk->Intersection(e, M, chunk->Transform(reference), col)) {
+ any = true;
+ }
+ }
+ }
+ }
+ return any;
}
bool World::Intersection(
if (manhattan_radius(cur_chunk.Position() - reference) > 1) {
// chunk is not one of the 3x3x3 surrounding the entity
// since there's no entity which can extent over 16 blocks, they can be skipped
+ // TODO: change to indexed (like with entity)
continue;
}
if (cur_chunk.Intersection(box, M, cur_chunk.Transform(reference), col)) {
void World::Update(int dt) {
float fdt(dt * 0.001f);
for (Entity &entity : entities) {
- Update(entity, fdt);
- }
- for (Entity &entity : entities) {
- entity.Update(fdt);
+ entity.Update(*this, fdt);
}
for (Player &player : players) {
player.Update(dt);
}
}
-void World::Update(Entity &entity, float dt) {
- EntityState state(entity.GetState());
-
- EntityDerivative a(CalculateStep(entity, state, 0.0f, EntityDerivative()));
- EntityDerivative b(CalculateStep(entity, state, dt * 0.5f, a));
- EntityDerivative c(CalculateStep(entity, state, dt * 0.5f, b));
- EntityDerivative d(CalculateStep(entity, state, dt, c));
-
- EntityDerivative f;
- constexpr float sixth = 1.0f / 6.0f;
- f.position = sixth * ((a.position + 2.0f * (b.position + c.position)) + d.position);
- f.velocity = sixth * ((a.velocity + 2.0f * (b.velocity + c.velocity)) + d.velocity);
-
- state.block_pos += f.position * dt;
- state.velocity += f.velocity * dt;
- state.AdjustPosition();
-
- entity.SetState(state);
-}
-
-EntityDerivative World::CalculateStep(
+void World::ResolveWorldCollision(
const Entity &entity,
- const EntityState &cur,
- float dt,
- const EntityDerivative &delta
+ EntityState &state
) {
- EntityState next(cur);
- next.block_pos += delta.position * dt;
- next.velocity += delta.velocity * dt;
- next.AdjustPosition();
-
- if (dot(next.velocity, next.velocity) > entity.MaxVelocity() * entity.MaxVelocity()) {
- next.velocity = normalize(next.velocity) * entity.MaxVelocity();
+ col.clear();
+ if (!entity.WorldCollidable() || !Intersection(entity, state, col)) {
+ // no collision, no fix
+ return;
}
-
- EntityDerivative out;
- out.position = next.velocity;
- out.velocity = CalculateForce(entity, next); // by mass = 1kg
- return out;
-}
-
-glm::vec3 World::CalculateForce(
- const Entity &entity,
- const EntityState &state
-) {
- glm::vec3 force(ControlForce(entity, state) + CollisionForce(entity, state) + Gravity(entity, state));
- if (dot(force, force) > entity.MaxControlForce() * entity.MaxControlForce()) {
- return normalize(force) * entity.MaxControlForce();
- } else {
- return force;
+ glm::vec3 correction = CombinedInterpenetration(state, col);
+ // correction may be zero in which case normalize() returns NaNs
+ if (iszero(correction)) {
+ return;
}
+ // if entity is already going in the direction of correction,
+ // let the problem resolve itself
+ if (dot(state.velocity, correction) >= 0.0f) {
+ return;
+ }
+ // apply correction, maybe could use some damping, gotta test
+ state.pos.block += correction;
+ // kill velocity?
+ glm::vec3 normal_velocity(proj(state.velocity, correction));
+ state.velocity -= normal_velocity;
}
-glm::vec3 World::ControlForce(
- const Entity &entity,
- const EntityState &state
-) {
- return entity.ControlForce(state);
-}
-
-namespace {
-
-std::vector<WorldCollision> col;
-
-}
-
-glm::vec3 World::CollisionForce(
- const Entity &entity,
- const EntityState &state
-) {
- col.clear();
- if (entity.WorldCollidable() && Intersection(entity, state, col)) {
- // determine displacement for each cardinal axis and move entity accordingly
- glm::vec3 min_pen(0.0f);
- glm::vec3 max_pen(0.0f);
- for (const WorldCollision &c : col) {
- if (!c.Blocks()) continue;
- glm::vec3 local_pen(c.normal * c.depth);
- // swap if neccessary (normal may point away from the entity)
- if (dot(c.normal, state.RelativePosition(c.ChunkPos()) - c.BlockCoords()) > 0) {
- local_pen *= -1;
+glm::vec3 World::CombinedInterpenetration(
+ const EntityState &state,
+ const std::vector<WorldCollision> &col
+) noexcept {
+ // determine displacement for each cardinal axis and move entity accordingly
+ glm::vec3 min_pen(0.0f);
+ glm::vec3 max_pen(0.0f);
+ for (const WorldCollision &c : col) {
+ if (!c.Blocks()) continue;
+ glm::vec3 normal(c.normal);
+ // swap if neccessary (normal may point away from the entity)
+ if (dot(normal, state.RelativePosition(c.ChunkPos()) - c.BlockCoords()) < 0) {
+ normal = -normal;
+ }
+ // check if block surface is "inside"
+ Block::Face coll_face = Block::NormalFace(normal);
+ BlockLookup neighbor(c.chunk, c.BlockPos(), coll_face);
+ if (neighbor && neighbor.FaceFilled(Block::Opposite(coll_face))) {
+ // yep, so ignore this contact
+ continue;
+ }
+ glm::vec3 local_pen(normal * c.depth);
+ min_pen = min(min_pen, local_pen);
+ max_pen = max(max_pen, local_pen);
+ }
+ glm::vec3 pen(0.0f);
+ // only apply correction for axes where penetration is only in one direction
+ for (std::size_t i = 0; i < 3; ++i) {
+ if (min_pen[i] < -std::numeric_limits<float>::epsilon()) {
+ if (max_pen[i] < std::numeric_limits<float>::epsilon()) {
+ pen[i] = min_pen[i];
}
- min_pen = min(min_pen, local_pen);
- max_pen = max(max_pen, local_pen);
+ } else {
+ pen[i] = max_pen[i];
}
- glm::vec3 correction(0.0f);
- // only apply correction for axes where penetration is only in one direction
- for (std::size_t i = 0; i < 3; ++i) {
- if (min_pen[i] < -std::numeric_limits<float>::epsilon()) {
- if (max_pen[i] < std::numeric_limits<float>::epsilon()) {
- correction[i] = -min_pen[i];
+ }
+ return pen;
+}
+
+glm::vec3 World::GravityAt(const ExactLocation &loc) const noexcept {
+ glm::vec3 force(0.0f);
+ ExactLocation::Coarse begin(loc.chunk - 1);
+ ExactLocation::Coarse end(loc.chunk + 2);
+
+ for (ExactLocation::Coarse pos(begin); pos.z < end.z; ++pos.z) {
+ for (pos.y = begin.y; pos.y < end.y; ++pos.y) {
+ for (pos.x = begin.x; pos.x < end.x; ++pos.x) {
+ const Chunk *chunk = chunks.Get(pos);
+ if (chunk) {
+ force += chunk->GravityAt(loc);
}
- } else {
- correction[i] = -max_pen[i];
}
}
- // correction may be zero in which case normalize() returns NaNs
- if (dot(correction, correction) < std::numeric_limits<float>::epsilon()) {
- return glm::vec3(0.0f);
- }
- glm::vec3 normal(normalize(correction));
- glm::vec3 normal_velocity(normal * dot(state.velocity, normal));
- // apply force proportional to penetration
- // use velocity projected onto normal as damper
- constexpr float k = 1000.0f; // spring constant
- constexpr float b = 10.0f; // damper constant
- const glm::vec3 x(-correction); // endpoint displacement from equilibrium in m
- const glm::vec3 v(normal_velocity); // relative velocity between endpoints in m/s
- return (((-k) * x) - (b * v)); // times 1kg/s, in kg*m/s²
- } else {
- return glm::vec3(0.0f);
}
-}
-glm::vec3 World::Gravity(
- const Entity &entity,
- const EntityState &state
-) {
- return glm::vec3(0.0f);
+ return force;
}
World::EntityHandle World::RemoveEntity(EntityHandle &eh) {
void World::Render(Viewport &viewport) {
DirectionalLighting &entity_prog = viewport.EntityProgram();
- entity_prog.SetLightDirection(light_direction);
entity_prog.SetFogDensity(fog_density);
+ glm::vec3 light_dir;
+ glm::vec3 light_col;
+ glm::vec3 ambient_col;
for (Entity &entity : entities) {
glm::mat4 M(entity.Transform(players.front().GetEntity().ChunkCoords()));
if (!CullTest(entity.Bounds(), entity_prog.GetVP() * M)) {
+ GetLight(entity, light_dir, light_col, ambient_col);
+ entity_prog.SetLightDirection(light_dir);
+ entity_prog.SetLightColor(light_col);
+ entity_prog.SetAmbientColor(ambient_col);
entity.Render(M, entity_prog);
}
}
}
+// this should interpolate based on the fractional part of entity's block position
+void World::GetLight(
+ const Entity &e,
+ glm::vec3 &dir,
+ glm::vec3 &col,
+ glm::vec3 &amb
+) {
+ BlockLookup center(chunks.Get(e.ChunkCoords()), e.Position());
+ if (!center) {
+ // chunk unavailable, so make it really dark and from
+ // some arbitrary direction
+ dir = glm::vec3(1.0f, 2.0f, 3.0f);
+ col = glm::vec3(0.025f); // ~0.8^15
+ return;
+ }
+ glm::ivec3 base(center.GetBlockPos());
+ int base_light = center.GetLight();
+ int max_light = 0;
+ int min_light = 15;
+ glm::ivec3 acc(0, 0, 0);
+ for (glm::ivec3 offset(-1, -1, -1); offset.z < 2; ++offset.z) {
+ for (offset.y = -1; offset.y < 2; ++offset.y) {
+ for (offset.x = -1; offset.x < 2; ++offset.x) {
+ BlockLookup block(¢er.GetChunk(), center.GetBlockPos() + offset);
+ if (!block) {
+ // missing, just ignore it
+ continue;
+ }
+ // otherwise, accumulate the difference times direction
+ acc += offset * (base_light - block.GetLight());
+ max_light = std::max(max_light, block.GetLight());
+ min_light = std::min(min_light, block.GetLight());
+ }
+ }
+ }
+ dir = acc;
+ col = glm::vec3(std::pow(0.8f, 15 - max_light));
+ amb = glm::vec3(std::pow(0.8f, 15 - min_light));
+}
+
namespace {
PrimitiveMesh::Buffer debug_buf;