Combat System Basics

Important LSL Combat Concepts:

1. Damage in LSL:

llSetDamage(float) - Sets collision damage
llRezObject() - Creates bullets/projectiles
Damage only works on land with damage enabled

2. Health Tracking:

llGetHealth() - Current avatar health (0-100)
CHANGED_REGION - Detect region changes
Attachments can monitor and display health

Combat System Components

Weapons

Objects that deal damage through collision or rezzing projectiles

Health Systems

HUDs or attachments that monitor and display avatar health

Respawn Logic

Teleport players to spawn points when health reaches zero

System 1: Basic Raycast Gun

A simple gun that shoots invisible bullets dealing damage on hit.

// Basic Raycast Gun - Click to shoot damage-dealing bullets

float DAMAGE = 15.0;        // Damage per hit (out of 100 health)
float BULLET_SPEED = 50.0;  // How fast bullet travels
float RANGE = 96.0;         // Maximum bullet range (meters)
float FIRE_RATE = 0.5;      // Delay between shots (seconds)
integer canFire = TRUE;

default
{
    state_entry()
    {
        llRequestPermissions(llGetOwner(), PERMISSION_TRIGGER_ANIMATION);
        llSay(0, "🔫 Gun ready. Click to fire!");
    }
    
    touch_start(integer num)
    {
        if (!canFire) return;  // Prevent rapid fire
        
        canFire = FALSE;
        
        // Get shooter's position and rotation
        vector startPos = llGetPos();
        rotation gunRot = llGetRot();
        
        // Calculate bullet trajectory (forward direction)
        vector direction = llRot2Fwd(gunRot);
        
        // Cast a ray to detect what we hit
        list raycast = llCastRay(
            startPos,
            startPos + (direction * RANGE),
            [RC_REJECT_TYPES, RC_REJECT_PHYSICAL | RC_REJECT_LAND]
        );
        
        // Check if we hit something
        integer hitCount = llList2Integer(raycast, -1);
        
        if (hitCount > 0)
        {
            key hitTarget = llList2Key(raycast, 0);
            
            // Create damage-dealing projectile at hit location
            vector hitPos = llList2Vector(raycast, 1);
            
            // Visual/audio feedback
            llPlaySound("gunshot_sound_uuid", 1.0);
            llParticleSystem([]);  // Add muzzle flash particles here
            
            llSay(0, "💥 HIT! " + llKey2Name(hitTarget));
        }
        else
        {
            llSay(0, "❌ MISS");
        }
        
        // Fire rate delay
        llSleep(FIRE_RATE);
        canFire = TRUE;
    }
}

Setting Up Your Gun:

Create a gun-shaped prim (or link multiple prims)
Make it an attachment (Edit → More → Attach To → Right Hand)
Insert this script into the gun
Important: Make sure you're in a damage-enabled region to test!

System 2: Melee Weapon (Sword)

A sword that deals damage through collision when swung.

// Melee Sword - Collision-based damage weapon

float MELEE_DAMAGE = 25.0;  // Damage per hit
float SWING_COOLDOWN = 1.0;  // Seconds between swings
integer isSwinging = FALSE;

default
{
    state_entry()
    {
        // Enable damage on collision
        llSetStatus(STATUS_PHANTOM, FALSE);  // Make solid for collision
        llCollisionSound("", 0.0);  // Disable default collision sound
        
        llSay(0, "⚔️ Sword ready. Click to swing!");
    }
    
    touch_start(integer num)
    {
        if (isSwinging) return;  // Can't swing again yet
        
        isSwinging = TRUE;
        
        // Visual swing animation (rotate sword)
        rotation originalRot = llGetLocalRot();
        rotation swingRot = llEuler2Rot(<0, 90*DEG_TO_RAD, 0>);
        
        llSetLocalRot(originalRot * swingRot);
        
        // Enable damage during swing
        llSetDamage(MELEE_DAMAGE);
        
        // Swing sound effect
        llPlaySound("sword_swing_uuid", 1.0);
        
        // Wait for swing to complete
        llSleep(0.3);
        
        // Return to original position
        llSetLocalRot(originalRot);
        
        // Disable damage
        llSetDamage(0.0);
        
        // Cooldown period
        llSleep(SWING_COOLDOWN);
        isSwinging = FALSE;
    }
    
    collision_start(integer num)
    {
        // Only register hits during active swing
        if (!isSwinging) return;
        
        integer i;
        for (i = 0; i < num; i++)
        {
            key hitKey = llDetectedKey(i);
            string hitName = llDetectedName(i);
            
            // Don't damage the owner
            if (hitKey != llGetOwner())
            {
                llPlaySound("metal_hit_uuid", 1.0);
                llSay(0, "⚔️ HIT: " + hitName + " for " + (string)MELEE_DAMAGE + " damage!");
            }
        }
    }
}

Collision Damage Tips:

llSetDamage() only works on regions with damage enabled
Damage is dealt per collision - fast movement = more hits = more damage
Use phantom mode when NOT swinging to avoid accidental damage
Physical objects deal more consistent collision damage

System 3: Health Monitoring HUD

A HUD attachment that displays your current health and alerts when low.

// Health HUD - Displays avatar health with visual bar

float health = 100.0;
float LOW_HEALTH_THRESHOLD = 25.0;  // Alert below 25%
float UPDATE_RATE = 1.0;  // Check health every second

// Display health as colored text
updateHealthDisplay()
{
    health = llGetHealth();
    
    // Choose color based on health level
    vector color;
    if (health > 75.0)
        color = <0, 1, 0>;  // Green - healthy
    else if (health > 50.0)
        color = <1, 1, 0>;  // Yellow - wounded
    else if (health > 25.0)
        color = <1, 0.5, 0>;  // Orange - critical
    else
        color = <1, 0, 0>;  // Red - dying
    
    // Display health percentage
    string healthText = "HP: " + (string)(integer)health + "%";
    llSetText(healthText, color, 1.0);
    
    // Low health alert
    if (health < LOW_HEALTH_THRESHOLD && health > 0)
    {
        llOwnerSay("⚠️ WARNING: Low health! " + (string)(integer)health + "%");
    }
    
    // Death detection
    if (health <= 0)
    {
        llOwnerSay("💀 You have died!");
        llSetText("DEAD", <0.5, 0, 0>, 1.0);
    }
}

default
{
    state_entry()
    {
        llRequestPermissions(llGetOwner(), PERMISSION_ATTACH);
        updateHealthDisplay();
        llSetTimerEvent(UPDATE_RATE);
    }
    
    timer()
    {
        updateHealthDisplay();
    }
    
    attach(key id)
    {
        if (id != NULL_KEY)
        {
            // Attached - start monitoring
            updateHealthDisplay();
            llSetTimerEvent(UPDATE_RATE);
        }
        else
        {
            // Detached - stop monitoring
            llSetTimerEvent(0.0);
        }
    }
    
    touch_start(integer num)
    {
        // Manual health check on click
        updateHealthDisplay();
        llOwnerSay("Current health: " + (string)(integer)health + "%");
    }
}

Creating a Visual Health Bar

Instead of text, use texture UV mapping to show a graphical health bar:

llScaleTexture(health/100.0, 1.0, ALL_SIDES);

Scales texture horizontally based on health percentage.

Audio Alerts

Add heartbeat sound when health is critical:

if (health < 30) llLoopSound("heartbeat", 1.0);

Creates tension and urgency during combat.

System 4: Advanced Damage Receiver

A script that detects damage, tracks who hit you, and logs combat statistics.

// Damage Receiver - Tracks damage sources and combat stats

integer totalDamageTaken = 0;
list attackers = [];  // List of [attacker_key, damage_dealt]

default
{
    state_entry()
    {
        llOwnerSay("🛡️ Damage tracking active. Combat stats enabled.");
    }
    
    changed(integer change)
    {
        if (change & CHANGED_HEALTH)
        {
            float currentHealth = llGetHealth();
            float damageTaken = 100.0 - currentHealth;
            
            if (damageTaken > totalDamageTaken)
            {
                float recentDamage = damageTaken - totalDamageTaken;
                totalDamageTaken = (integer)damageTaken;
                
                // Detect who damaged us (requires collision or sensor data)
                llOwnerSay("💔 Took " + (string)(integer)recentDamage + " damage! Health: " + (string)(integer)currentHealth + "%");
                
                // Visual damage indicator (red flash)
                llSetColor(<1, 0, 0>, ALL_SIDES);
                llSleep(0.2);
                llSetColor(<1, 1, 1>, ALL_SIDES);
            }
            
            // Death detection
            if (currentHealth <= 0)
            {
                llOwnerSay("💀 You died! Total damage taken: " + (string)totalDamageTaken);
                
                // Reset stats
                totalDamageTaken = 0;
                attackers = [];
                
                // Trigger respawn (see System 5)
            }
        }
    }
    
    collision_start(integer num)
    {
        // Track who's hitting us with melee/collision damage
        integer i;
        for (i = 0; i < num; i++)
        {
            key attacker = llDetectedKey(i);
            
            if (attacker != llGetOwner())  // Don't log self-damage
            {
                llOwnerSay("⚔️ Hit by: " + llDetectedName(i));
                
                // Add to attackers list (track for kill credit)
                integer index = llListFindList(attackers, [attacker]);
                if (index == -1)
                {
                    attackers += [attacker, 1];  // New attacker
                }
                else
                {
                    // Increment hit count
                    integer hits = llList2Integer(attackers, index + 1) + 1;
                    attackers = llListReplaceList(attackers, [hits], index + 1, index + 1);
                }
            }
        }
    }
    
    touch_start(integer num)
    {
        // Display combat stats
        llOwnerSay("📊 COMBAT STATS:");
        llOwnerSay("Health: " + (string)(integer)llGetHealth() + "%");
        llOwnerSay("Damage Taken: " + (string)totalDamageTaken);
        llOwnerSay("Attackers: " + (string)(llGetListLength(attackers)/2));
    }
}

System 5: Respawn System

Automatically teleport players to spawn points when they die and restore health.

// Respawn System - Teleports to spawn and restores health on death

vector SPAWN_POINT = <128, 128, 25>;  // Respawn coordinates
float RESPAWN_DELAY = 3.0;  // Seconds before respawn

default
{
    state_entry()
    {
        llRequestPermissions(llGetOwner(), PERMISSION_TELEPORT);
        llSetTimerEvent(1.0);  // Check health every second
    }
    
    run_time_permissions(integer perm)
    {
        if (perm & PERMISSION_TELEPORT)
        {
            llOwnerSay("✅ Respawn system ready. You will respawn if killed.");
        }
    }
    
    timer()
    {
        float health = llGetHealth();
        
        if (health <= 0)
        {
            // Player is dead - initiate respawn
            llSetTimerEvent(0.0);  // Stop health checks
            
            llOwnerSay("💀 You died! Respawning in " + (string)(integer)RESPAWN_DELAY + " seconds...");
            
            // Death effects (optional)
            llPlaySound("death_sound_uuid", 1.0);
            
            // Wait before respawn
            llSleep(RESPAWN_DELAY);
            
            // Teleport to spawn point
            llOwnerSay("🔄 Respawning...");
            llTeleportAgent(llGetOwner(), "", SPAWN_POINT, ZERO_VECTOR);
            
            // Note: Health auto-restores to 100 after teleport in most grids
            // If not, use region restart or experience tools
            
            llSleep(2.0);
            llOwnerSay("✨ Respawned! Health restored to 100%");
            
            // Resume health monitoring
            llSetTimerEvent(1.0);
        }
    }
    
    changed(integer change)
    {
        if (change & CHANGED_TELEPORT)
        {
            llOwnerSay("📍 Teleported to: " + (string)llGetPos());
        }
    }
}

Important Respawn Notes:

PERMISSION_TELEPORT must be granted for respawn to work
Teleporting within the same region auto-restores health to 100 in most grids
For cross-region respawns, you may need Experience permissions to set health
Alternative: Use llTeleportAgent() to a health-restore zone/object

System 6: Team-Based Combat

Prevent friendly fire using group/team detection - only damage enemies!

// Team Combat System - Group-based friendly fire prevention

float DAMAGE = 20.0;
key TEAM_GROUP;  // UUID of team group (set in state_entry)

default
{
    state_entry()
    {
        // Get the group this object is set to
        list details = llGetObjectDetails(llGetKey(), [OBJECT_GROUP]);
        TEAM_GROUP = llList2Key(details, 0);
        
        if (TEAM_GROUP == NULL_KEY)
        {
            llOwnerSay("⚠️ WARNING: No group set! Set object to team group to enable friendly fire protection.");
        }
        else
        {
            llOwnerSay("🛡️ Team weapon ready. Friendly fire protection enabled.");
        }
    }
    
    touch_start(integer num)
    {
        // Detect targets in front of weapon
        vector startPos = llGetPos();
        rotation gunRot = llGetRot();
        vector direction = llRot2Fwd(gunRot);
        
        // Raycast to find target
        list raycast = llCastRay(
            startPos,
            startPos + (direction * 50.0),
            [RC_REJECT_TYPES, RC_REJECT_PHYSICAL | RC_REJECT_LAND]
        );
        
        integer hitCount = llList2Integer(raycast, -1);
        
        if (hitCount > 0)
        {
            key hitKey = llList2Key(raycast, 0);
            
            // Check if target is an avatar
            if (llGetAgentSize(hitKey) != ZERO_VECTOR)
            {
                // It's an avatar - check team membership
                list agentGroups = llGetObjectDetails(hitKey, [OBJECT_GROUP]);
                key targetGroup = llList2Key(agentGroups, 0);
                
                if (targetGroup == TEAM_GROUP && TEAM_GROUP != NULL_KEY)
                {
                    // FRIENDLY - Don't shoot!
                    llOwnerSay("🛡️ FRIENDLY: " + llKey2Name(hitKey) + " is on your team!");
                    llPlaySound("error_beep_uuid", 0.5);
                }
                else
                {
                    // ENEMY - Deal damage!
                    llOwnerSay("💥 HIT ENEMY: " + llKey2Name(hitKey));
                    llPlaySound("gunshot_uuid", 1.0);
                    
                    // Deal damage (requires bullet rezzing or collision in damage-enabled region)
                    // Example: llRezObject("bullet", hitPos, ZERO_VECTOR, ZERO_ROTATION, 0);
                }
            }
        }
    }
}

Setting Up Teams

Create groups for each team (Blue Team, Red Team, etc.)
Set weapons to the team's group (Edit → General → Set Group)
Players wear/activate team tag when in combat
Weapons automatically detect group membership!

Advanced: Kill/Death Tracking

Use HTTP requests to external database:

llHTTPRequest(api_url, [HTTP_METHOD, "POST"], "kill=" + killer + "&victim=" + victim);

Track leaderboards, K/D ratios, team scores!

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