HTWeapon: Part 3 – Creating A Muzzle Flash

Video Version

Subject: HTWeapon: HTWeapon: Part 3 – Creating A Muzzle Flash
Skill Level: Beginner
Run-Time: 1 Hour
Author: Michael Allar
Notes: How to implement a ParticleSystem to use as a muzzle flash for your weapon.

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Download:     Low-Res (156MB) Hi-Res (226MB)

Written Version

Subject: HTWeapon: Part 3 – Creating A Muzzle Flash
Skill Level: Beginner
Author: Michael Allar
Notes: How to implement a ParticleSystem to use as a muzzle flash for your weapon.



See video for an in-depth explanation. Sorry about the indentation, it seems like my indentation will not survive copy paste… D:

HTWeapon

[csharp]/*******************************************************************************
HTWeapon

Creation date: 08/03/2010 06:21
Copyright (c) 2010, Allar

*******************************************************************************/

class HTWeapon extends UDKWeapon;

/** Max ammo count */
var int MaxAmmoCount;

/** Holds the amount of ammo used for a given shot */
var array<int> ShotCost;

/** Offset from view center */
var(FirstPerson) vector    PlayerViewOffset;

/** HUD Stuff */
var Texture CrosshairImage;
var UIRoot.TextureCoordinates CrosshairCoordinates;

/*********************************************************************************************
Muzzle Flash
********************************************************************************************* */

/** Holds the name of the socket to attach a muzzle flash too */
var name                    MuzzleFlashSocket;

/** Muzzle flash PSC and Templates*/
var HTParticleSystemComponent    MuzzleFlashPSC;

/** Array of Particle Systems for our firemodes */
var array<ParticleSystem>            MuzzleFlashPSCTemplate;

/** How long the Muzzle Flash should be there */
var() float                    MuzzleFlashDuration;

/** Whether muzzleflash has been initialized */
var bool                    bMuzzleFlashAttached;

/*********************************************************************************************
Replication
********************************************************************************************* */
simulated event ReplicatedEvent(name VarName)
{
if ( VarName == 'AmmoCount' )
{
if ( !HasAnyAmmo() )
{
WeaponEmpty();
}
}
else
{
Super.ReplicatedEvent(VarName);
}
}

/*********************************************************************************************
Muzzle Flash Methods
********************************************************************************************* */

/**
* PlayFireEffects Is the root function that handles all of the effects associated with
* a weapon.  This function creates the 1st person effects.  It should only be called
* on a locally controlled player.
*/
simulated function PlayFireEffects( byte FireModeNum, optional vector HitLocation )
{
// Start muzzle flash effect
CauseMuzzleFlash();
}
/**
* Called on a client, this function Attaches the MuzzleFlashParticleSystemComponent
*/
simulated function AttachMuzzleFlash()
{
local SkeletalMeshComponent SKMesh;

// Attach the Muzzle Flash
bMuzzleFlashAttached = true;
SKMesh = SkeletalMeshComponent(Mesh);
if (  SKMesh != none )
{
//if our weapon has at least one muzzle flash
//lets attach our muzzle flash particle system component
if ( MuzzleFlashPSCTemplate.Length > 0 )
{
MuzzleFlashPSC = new(Outer) class'HTParticleSystemComponent';
MuzzleFlashPSC.bAutoActivate = false;
MuzzleFlashPSC.SetDepthPriorityGroup(SDPG_Foreground);
MuzzleFlashPSC.SetFOV(UDKSkeletalMeshComponent(SKMesh).FOV);
SKMesh.AttachComponentToSocket(MuzzleFlashPSC, MuzzleFlashSocket);
}
}
}

/**
* Causes the muzzle flash to turn on and setup a time to
* turn it back off again.
*/
simulated event CauseMuzzleFlash()
{
local HTPawn P;
local ParticleSystem MuzzleTemplate;

PrintScreenDebug("Causing Muzzle Flash");

//If we aren't the client, make sure this pawn exists
//before we create a muzzle flash for it
if ( WorldInfo.NetMode != NM_Client )
{
P = HTPawn(Instigator);
if ( P == None )
{
return;
}
}

//CauseMuzzleFlashLight();

//Only proceed if our firing mode has a muzzle flash
if (Instigator.FiringMode < MuzzleFlashPSCTemplate.Length)
{
if ( !bMuzzleFlashAttached )
{
AttachMuzzleFlash();
}
if (MuzzleFlashPSCTemplate[Instigator.FiringMode] != None)
{
if (!MuzzleFlashPSC.bIsActive || MuzzleFlashPSC.bWasDeactivated)
{
MuzzleTemplate = MuzzleFlashPSCTemplate[Instigator.FiringMode];

//If our current PSC is using a different muzzle flash particle
//Lets go ahead and swap it with the one we need
if (MuzzleTemplate != MuzzleFlashPSC.Template)
{
MuzzleFlashPSC.SetTemplate(MuzzleTemplate);
}
SetMuzzleFlashParams(MuzzleFlashPSC);
MuzzleFlashPSC.ActivateSystem();
}
}
// Set when to turn it off.
SetTimer(MuzzleFlashDuration,false,'MuzzleFlashTimer');
}
}

/**
* Turns the MuzzleFlashPSC off
*/
simulated event MuzzleFlashTimer()
{
if (MuzzleFlashPSC != none)
{
MuzzleFlashPSC.DeactivateSystem();
}
}

simulated event StopMuzzleFlash()
{
ClearTimer('MuzzleFlashTimer');
MuzzleFlashTimer();

if ( MuzzleFlashPSC != none )
{
MuzzleFlashPSC.DeactivateSystem();
}
}

/**
* Allows a child to setup custom parameters on the muzzle flash
*/

simulated function SetMuzzleFlashParams(ParticleSystemComponent PSC)
{
return;
}

/*********************************************************************************************
* Ammunition / Inventory
*********************************************************************************************/

simulated function int GetAmmoCount()
{
return AmmoCount;
}
/*
* Consumes some of the ammo
*/
function ConsumeAmmo( byte FireModeNum )
{
// Subtract the Ammo
AddAmmo(-ShotCost[FireModeNum]);
}

/**
* This function is used to add ammo back to a weapon.  It's called from the Inventory Manager
*/
function int AddAmmo( int Amount )
{
AmmoCount = Clamp(AmmoCount + Amount,0,MaxAmmoCount);
return AmmoCount;
}

/**
* Returns true if the ammo is maxed out
*/
simulated function bool AmmoMaxed(int mode)
{
return (AmmoCount >= MaxAmmoCount);
}

/**
* This function checks to see if the weapon has any ammo available for a given fire mode.
*
* @param    FireModeNum        - The Fire Mode to Test For
* @param    Amount            - [Optional] Check to see if this amount is available.  If 0 it will default to checking
*                              for the ShotCost
*/
simulated function bool HasAmmo( byte FireModeNum, optional int Amount )
{
if (Amount==0)
return (AmmoCount >= ShotCost[FireModeNum]);
else
return ( AmmoCount >= Amount );
}

/**
* returns true if this weapon has any ammo
*/
simulated function bool HasAnyAmmo()
{
return ( ( AmmoCount > 0 ) || (ShotCost[0]==0 && ShotCost[1]==0) );
}

/**
* This function retuns how much of the clip is empty.
*/
simulated function float DesireAmmo(bool bDetour)
{
return (1.f - float(AmmoCount)/MaxAmmoCount);
}

/**
* Returns true if the current ammo count is less than the default ammo count
*/
simulated function bool NeedAmmo()
{
return ( AmmoCount < Default.AmmoCount );
}

/**
* Cheat Help function the loads out the weapon
*
* @param     bUseWeaponMax     - [Optional] If true, this function will load out the weapon
*                              with the actual maximum, not 999
*/
simulated function Loaded(optional bool bUseWeaponMax)
{
if (bUseWeaponMax)
AmmoCount = MaxAmmoCount;
else
AmmoCount = 999;
}

/**
* Called when the weapon runs out of ammo during firing
*/
simulated function WeaponEmpty()
{
// If we were firing, stop
if ( IsFiring() )
{
GotoState('Active');
}

if ( Instigator != none && Instigator.IsLocallyControlled() )
{
Instigator.InvManager.SwitchToBestWeapon( true );
}
}
/*********************************************************
*  HUD Stuff
*********************************************************/

/**
* Draw the Crosshairs
*/
simulated function DrawWeaponCrosshair( Hud HUD )
{
local vector2d CrosshairSize;
local float x,y, ScreenX, ScreenY;
local HTHUD    H;

H = HTHUD(HUD);
if ( H == None )
return;

CrosshairSize.Y = CrosshairCoordinates.VL * H.Canvas.ClipY/720;
CrosshairSize.X = CrosshairSize.Y * ( CrosshairCoordinates.UL / CrosshairCoordinates.VL );

X = H.Canvas.ClipX * 0.5;
Y = H.Canvas.ClipY * 0.5;
ScreenX = X - (CrosshairSize.X * 0.5);
ScreenY = Y - (CrosshairSize.Y * 0.5);
if ( CrosshairImage != none )
{
// crosshair drop shadow
H.Canvas.DrawColor = H.CrosshairShadowColor;
H.Canvas.SetPos( ScreenX+1, ScreenY+1 );
H.Canvas.DrawTile(CrosshairImage,CrosshairSize.X, CrosshairSize.Y, CrossHairCoordinates.U, CrossHairCoordinates.V, CrossHairCoordinates.UL,CrossHairCoordinates.VL);

H.Canvas.DrawColor = H.CrosshairColor;
H.Canvas.SetPos(ScreenX, ScreenY);
H.Canvas.DrawTile(CrosshairImage,CrosshairSize.X, CrosshairSize.Y, CrossHairCoordinates.U, CrossHairCoordinates.V, CrossHairCoordinates.UL,CrossHairCoordinates.VL);
}
}

function PrintScreenDebug(string debugText)
{
local PlayerController PC;
PC = PlayerController(Pawn(Owner).Controller);
if (PC != None)
PC.ClientMessage("HTWeapon: " $ debugText);
}

simulated function AttachWeaponTo( SkeletalMeshComponent MeshCpnt, optional Name SocketName )
{
local HTPawn HTP;

HTP = HTPawn(Instigator);
PrintScreenDebug("Attaching Weapon");
// Attach 1st Person Muzzle Flashes, etc,
if ( Instigator.IsFirstPerson() )
{
AttachComponent(Mesh);
EnsureWeaponOverlayComponentLast();
SetHidden(False);
Mesh.SetLightEnvironment(HTP.LightEnvironment);
PrintScreenDebug("First Person Weapon Attached");
}
else
{
SetHidden(True);
if (HTP != None)
{
Mesh.SetLightEnvironment(HTP.LightEnvironment);
}
}
//SetSkin(HTPawn(Instigator).ReplicatedBodyMaterial);
}

simulated event SetPosition(UDKPawn Holder)
{
local vector DrawOffset, ViewOffset, FinalLocation;
local rotator NewRotation, FinalRotation, SpecRotation;
local PlayerController PC;
local vector2D ViewportSize;
local bool bIsWideScreen;
local vector SpecViewLoc;

if ( !Holder.IsFirstPerson() )
return;

Mesh.SetHidden(False);

foreach LocalPlayerControllers(class'PlayerController', PC)
{
LocalPlayer(PC.Player).ViewportClient.GetViewportSize(ViewportSize);
break;
}
bIsWideScreen = (ViewportSize.Y > 0.f) && (ViewportSize.X/ViewportSize.Y > 1.7);

Mesh.SetScale3D(default.Mesh.Scale3D);
Mesh.SetRotation(default.Mesh.Rotation);

ViewOffset = PlayerViewOffset;

// Calculate the draw offset
if ( Holder.Controller == None )
{

if ( DemoRecSpectator(PC) != None )
{
PC.GetPlayerViewPoint(SpecViewLoc, SpecRotation);
DrawOffset = ViewOffset >> SpecRotation;
//DrawOffset += UTPawn(Holder).WeaponBob(BobDamping, JumpDamping);
FinalLocation = SpecViewLoc + DrawOffset;
SetLocation(FinalLocation);
SetBase(Holder);

// Add some rotation leading
//SpecRotation.Yaw = LagRot(SpecRotation.Yaw & 65535, LastRotation.Yaw & 65535, MaxYawLag, 0);
//SpecRotation.Pitch = LagRot(SpecRotation.Pitch & 65535, LastRotation.Pitch & 65535, MaxPitchLag, 1);
//LastRotUpdate = WorldInfo.TimeSeconds;
//LastRotation = SpecRotation;

if ( bIsWideScreen )
{
//SpecRotation += WidescreenRotationOffset;
}
SetRotation(SpecRotation);
return;
}
else
{
DrawOffset = (ViewOffset >> Holder.GetBaseAimRotation()) + HTPawn(Holder).GetEyeHeight() * vect(0,0,1);
PrintScreenDebug("Setting DrawOffset to Holder Info");
}
}
else
{

DrawOffset.Z = HTPawn(Holder).GetEyeHeight();
//DrawOffset += HTPawn(Holder).WeaponBob(BobDamping, JumpDamping);

if ( HTPlayerController(Holder.Controller) != None )
{
DrawOffset += HTPlayerController(Holder.Controller).ShakeOffset >> Holder.Controller.Rotation;
}

DrawOffset = DrawOffset + ( ViewOffset >> Holder.Controller.Rotation );
}

// Adjust it in the world
FinalLocation = Holder.Location + DrawOffset;
SetLocation(FinalLocation);
SetBase(Holder);

NewRotation = (Holder.Controller == None) ? Holder.GetBaseAimRotation() : Holder.Controller.Rotation;

// Add some rotation leading
//if (Holder.Controller != None)
//{
//    FinalRotation.Yaw = LagRot(NewRotation.Yaw & 65535, LastRotation.Yaw & 65535, MaxYawLag, 0);
//    FinalRotation.Pitch = LagRot(NewRotation.Pitch & 65535, LastRotation.Pitch & 65535, MaxPitchLag, 1);
//    FinalRotation.Roll = NewRotation.Roll;
//}
//else
//{
FinalRotation = NewRotation;
//}
//LastRotUpdate = WorldInfo.TimeSeconds;
//LastRotation = NewRotation;

if ( bIsWideScreen )
{
//FinalRotation += WidescreenRotationOffset;
}
SetRotation(FinalRotation);
}

simulated state WeaponEquipping
{
simulated event BeginState(Name PreviousStateName)
{
PrintScreenDebug("Weapon Equipping");
AttachWeaponTo(Instigator.Mesh);
Super.BeginState(PreviousStateName);
}
}

simulated state Active
{
simulated event BeginState(Name PreviousStateName)
{
PrintScreenDebug("Active");
Super.BeginState(PreviousStateName);
}
}

simulated state WeaponFiring
{
simulated event BeginState(Name PreviousStateName)
{
PrintScreenDebug("Firing");
Super.BeginState(PreviousStateName);
}

/**
* We override BeginFire() so that we can check for zooming and/or empty weapons
*/

simulated function BeginFire( Byte FireModeNum )
{
// No Ammo, then do a quick exit.
if( !HasAmmo(FireModeNum) )
{
WeaponEmpty();
return;
}
Global.BeginFire(FireModeNum);
}
}

defaultproperties
{
//Our properties we made.

CrosshairImage=Texture2D'HTUI.Textures.T_UI_HUD_BaseA'
CrosshairCoordinates=(U=80,V=0,UL=50,VL=50)

MuzzleFlashSocket=MuzzleFlashSocket
MuzzleFlashDuration=0.05f
MuzzleFlashPSCTemplate(0)=ParticleSystem'HTEffects_Allar.Particles.PS_MuzzleFlash'

//Epic's default properties and stuff
Begin Object Name=FirstPersonMesh
DepthPriorityGroup=SDPG_Foreground
bOnlyOwnerSee=true
bOverrideAttachmentOwnerVisibility=true
CastShadow=false
bAllowAmbientOcclusion=false
End Object
Mesh=FirstPersonMesh

Begin Object Name=PickupMesh
bOnlyOwnerSee=false
CastShadow=false
bForceDirectLightMap=true
bCastDynamicShadow=false
CollideActors=false
BlockRigidBody=false
bUseAsOccluder=false
MaxDrawDistance=6000
bForceRefPose=1
bUpdateSkelWhenNotRendered=false
bIgnoreControllersWhenNotRendered=true
bAcceptsStaticDecals=FALSE
bAcceptsDynamicDecals=FALSE
bAllowAmbientOcclusion=false
End Object
DroppedPickupMesh=PickupMesh
PickupFactoryMesh=PickupMesh

MessageClass=class'UTPickupMessage'
DroppedPickupClass=class'UTDroppedPickup'

FiringStatesArray(0)=WeaponFiring
FiringStatesArray(1)=WeaponFiring

WeaponFireTypes(0)=EWFT_InstantHit
WeaponFireTypes(1)=EWFT_InstantHit

WeaponProjectiles(0)=none
WeaponProjectiles(1)=none

FireInterval(0)=+0.3
FireInterval(1)=+0.3

Spread(0)=0.0
Spread(1)=0.0

ShotCost(0)=1
ShotCost(1)=1

AmmoCount=5
MaxAmmoCount=5

InstantHitDamage(0)=0.0
InstantHitDamage(1)=0.0
InstantHitMomentum(0)=0.0
InstantHitMomentum(1)=0.0
InstantHitDamageTypes(0)=class'DamageType'
InstantHitDamageTypes(1)=class'DamageType'
WeaponRange=22000

ShouldFireOnRelease(0)=0
ShouldFireOnRelease(1)=0

DefaultAnimSpeed=0.9

EquipTime=+0.45
PutDownTime=+0.33
}[/csharp]

Download Project Source Code Here