eq2go/internal/spells/SPELL_PROCESS.md

4.1 KiB

Spell Processing System

Comprehensive spell casting engine managing all aspects of spell processing including timers, targeting, resource management, and heroic opportunities.

Components

SpellProcess - Core engine managing active spells, cast/recast timers, interrupt queues, spell queues, and heroic opportunities SpellTargeting - Target selection for all spell types (self, single, group, AOE, PBAE) with validation SpellResourceChecker - Resource validation/consumption for power, health, concentration, savagery, dissonance SpellManager - High-level coordinator integrating all systems with comprehensive casting API

Key Data Structures

// Active spell instance
type LuaSpell struct {
    Spell         *Spell    // Spell definition
    CasterID      int32     // Casting entity
    Targets       []int32   // Target list
    Timer         SpellTimer // Duration/tick timing
    NumCalls      int32     // Tick count
    Interrupted   bool      // Interrupt state
}

// Cast timing
type CastTimer struct {
    CasterID    int32         // Casting entity
    SpellID     int32         // Spell being cast
    StartTime   time.Time     // Cast start
    Duration    time.Duration // Cast time
}

// Cooldown timing
type RecastTimer struct {
    CasterID    int32         // Entity with cooldown
    SpellID     int32         // Spell on cooldown
    Duration    time.Duration // Cooldown time
    LinkedTimer int32         // Shared cooldown group
}

Usage

// Main spell processing loop (50ms intervals)
spellManager.ProcessSpells()

// Cast spell with full validation
err := spellManager.CastSpell(casterID, targetID, spellID)

// Interrupt casting
spellManager.InterruptSpell(entityID, spellID, errorCode, canceled, fromMovement)

// Queue management
spellManager.AddSpellToQueue(spellID, casterID, targetID, priority)
spellManager.RemoveSpellFromQueue(spellID, casterID)

// Status checks
ready := spellManager.IsSpellReady(spellID, casterID)
recastTime := spellManager.GetSpellRecastTime(spellID, casterID)
canCast, reason := spellManager.CanCastSpell(casterID, targetID, spellID)

// Resource checking
resourceChecker := spellManager.GetResourceChecker()
powerResult := resourceChecker.CheckPower(luaSpell, customPowerReq)
allResults := resourceChecker.CheckAllResources(luaSpell, 0, 0)
success := resourceChecker.ConsumeAllResources(luaSpell, 0, 0)

// Targeting
targeting := spellManager.GetTargeting()
targetResult := targeting.GetSpellTargets(luaSpell, options)

Effect Types (80+)

Stat Modifications: Health, power, stats (STR/AGI/STA/INT/WIS), resistances, attack, mitigation Spell Modifications: Cast time, power req, range, duration, resistibility, crit chance Actions: Damage, healing, DOT/HOT, resurrect, summon, mount, invisibility Control: Stun, root, mez, fear, charm, blind, kill Special: Change race/size/title, faction, exp, tradeskill bonuses

Target Types

TargetTypeSelf (0) - Self-only spells TargetTypeSingle (1) - Single target with validation TargetTypeGroup (2) - Group members TargetTypeGroupAE (3) - Group area effect TargetTypeAE (4) - True area effect TargetTypePBAE (5) - Point blank area effect

Interrupt System

Causes: Movement, damage, stun, mesmerize, fear, manual cancellation, out of range Processing: Queued interrupts processed every cycle with proper cleanup Error Codes: Match client expectations for proper UI feedback

Performance

  • 50ms Processing: Matches client update expectations
  • Efficient Indexing: Fast lookups by caster, spell, target
  • Thread Safety: Concurrent access with proper locking
  • Memory Management: Cleanup of expired timers and effects
  • Batch Operations: Multiple resource checks/targeting in single calls

Integration Points

Entity System: Caster/target info, position data, combat state Zone System: Position validation, line-of-sight, spawn management Group System: Group member targeting and coordination Database: Persistent spell data, character spell books Packet System: Client communication for spell states LUA System: Custom spell scripting (future)