132 lines
3.4 KiB
C++
132 lines
3.4 KiB
C++
#include "CombatSystem.h"
|
|
|
|
#include "EcsComponents.h"
|
|
#include "EntityAdmin.h"
|
|
|
|
static constexpr Tick kWeaponImpactDelayTicks = 5;
|
|
|
|
CombatSystem::CombatSystem(const GameConfig& config)
|
|
: m_config(config)
|
|
{
|
|
}
|
|
|
|
void CombatSystem::tick(Tick currentTick,
|
|
EntityAdmin& admin,
|
|
BuildingSystem& /*buildings*/,
|
|
std::vector<FireEvent>& outFireEvents)
|
|
{
|
|
// Ship weapons.
|
|
admin.forEach<Weapon, ThreatResponse, Position, Faction>(
|
|
[&](entt::entity e, Weapon& weapon, ThreatResponse& threat, Position& pos, Faction& faction)
|
|
{
|
|
weapon.currentTarget = threat.currentTarget;
|
|
resolveWeapon(e, weapon, pos, faction, currentTick, admin, outFireEvents);
|
|
});
|
|
|
|
// Station weapons.
|
|
admin.forEach<Weapon, Position, Faction>(
|
|
[&](entt::entity e, Weapon& weapon, Position& pos, Faction& faction)
|
|
{
|
|
resolveWeapon(e, weapon, pos, faction, currentTick, admin, outFireEvents);
|
|
});
|
|
}
|
|
|
|
void CombatSystem::resolveWeapon(
|
|
entt::entity shipEntity,
|
|
Weapon& weapon,
|
|
const Position& ownPos,
|
|
const Faction& ownFaction,
|
|
Tick currentTick,
|
|
EntityAdmin& admin,
|
|
std::vector<FireEvent>& out)
|
|
{
|
|
if (weapon.cooldownTicks > 0.0f)
|
|
{
|
|
weapon.cooldownTicks -= 1.0f;
|
|
}
|
|
if (weapon.cooldownTicks > 0.0f)
|
|
{
|
|
return;
|
|
}
|
|
|
|
// Validate or clear existing target.
|
|
if (weapon.currentTarget)
|
|
{
|
|
const entt::entity t = *weapon.currentTarget;
|
|
if (!admin.isValid(t) || !admin.hasAll<Position>(t))
|
|
{
|
|
weapon.currentTarget = std::nullopt;
|
|
}
|
|
else
|
|
{
|
|
const float distanceSquared = (ownPos.value - admin.get<Position>(t).value).lengthSquared();
|
|
if (distanceSquared > weapon.range * weapon.range)
|
|
{
|
|
weapon.currentTarget = std::nullopt;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Acquire a new target if needed (nearest opposing-faction ship).
|
|
if (!weapon.currentTarget)
|
|
{
|
|
float bestDistanceSquared = weapon.range * weapon.range;
|
|
admin.forEach<ShipIdentity, Position, Faction>(
|
|
[&](entt::entity candidate, const ShipIdentity& /*si*/,
|
|
const Position& candidatePos, const Faction& candidateFaction)
|
|
{
|
|
const bool isValidTarget = ownFaction.isEnemy
|
|
? !candidateFaction.isEnemy
|
|
: candidateFaction.isEnemy;
|
|
if (!isValidTarget)
|
|
{
|
|
return;
|
|
}
|
|
const float distanceSquared = (candidatePos.value - ownPos.value).lengthSquared();
|
|
if (distanceSquared < bestDistanceSquared)
|
|
{
|
|
bestDistanceSquared = distanceSquared;
|
|
weapon.currentTarget = candidate;
|
|
}
|
|
});
|
|
}
|
|
|
|
if (!weapon.currentTarget)
|
|
{
|
|
return;
|
|
}
|
|
|
|
const entt::entity targetEntity = *weapon.currentTarget;
|
|
m_pendingDamage.push_back({targetEntity, weapon.damage,
|
|
currentTick + kWeaponImpactDelayTicks});
|
|
|
|
FireEvent evt;
|
|
evt.shooter = shipEntity;
|
|
evt.target = targetEntity;
|
|
evt.emittedAt = currentTick;
|
|
out.push_back(evt);
|
|
|
|
weapon.cooldownTicks = static_cast<float>(kTickRateHz) / weapon.fireRateHz;
|
|
}
|
|
|
|
void CombatSystem::applyPendingDamage(Tick currentTick, EntityAdmin& admin)
|
|
{
|
|
std::vector<PendingDamage>::iterator it = m_pendingDamage.begin();
|
|
while (it != m_pendingDamage.end())
|
|
{
|
|
if (it->appliesAt <= currentTick)
|
|
{
|
|
if (admin.isValid(it->target) && admin.hasAll<Health>(it->target))
|
|
{
|
|
admin.get<Health>(it->target).hp -= it->amount;
|
|
}
|
|
it = m_pendingDamage.erase(it);
|
|
}
|
|
else
|
|
{
|
|
++it;
|
|
}
|
|
}
|
|
}
|
|
|