Using Glowshell tutorial - Half-Life

For this tutorial I will show you how to add glowshell to an entity. This effect can be useful for when you want an entity to be obvious to the player, for example, weapons in a dark room.

We will start by adding glowshell to a zombie.
Here is the half-life zombie. He doesn't have glowshell by default.

Now we will look at the zombie code which is zombie.cpp in the dlls folder of the SDK.

There are many parts of zombie.cpp

public:
	void Spawn( void );
	void Precache( void );
	void SetYawSpeed( void );
	int  Classify ( void );
	void HandleAnimEvent( MonsterEvent_t *pEvent );
	int IgnoreConditions ( void );

	float m_flNextFlinch;

	void PainSound( void );
	void AlertSound( void );
	void IdleSound( void );
	void AttackSound( void );

	static const char *pAttackSounds[];
	static const char *pIdleSounds[];
	static const char *pAlertSounds[];
	static const char *pPainSounds[];
	static const char *pAttackHitSounds[];
	static const char *pAttackMissSounds[];

For this tutorial, however, we will only need to change spawn. So go to void CZombie :: Spawn() on line 270
It should look like this:

//=========================================================
// Spawn
//=========================================================
void CZombie :: Spawn()
{
	Precache( );

	SET_MODEL(ENT(pev), "models/system/monsters/zombie.mdl");
	UTIL_SetSize( pev, VEC_HUMAN_HULL_MIN, VEC_HUMAN_HULL_MAX );

	pev->solid			= SOLID_SLIDEBOX;
	pev->movetype		= MOVETYPE_STEP;
	m_bloodColor		= BLOOD_COLOR_RED;
	pev->health			= gSkillData.zombieHealth;
	pev->view_ofs		= VEC_VIEW;// position of the eyes relative to monster's origin.
	m_flFieldOfView		= 0.5;// indicates the width of this monster's forward view cone ( as a dotproduct result )
	m_MonsterState		= MONSTERSTATE_NONE;
	m_afCapability		= bits_CAP_DOORS_GROUP;

	MonsterInit();
}

Go to the end of spawn, right after MonsterInit();

add this

pev->renderfx = kRenderFxGlowShell;

Compile the code and the zombie should now look like this:

Congratulations! You now have a glowing zombie!

But wait...

What if we want to make the glow a different color?

It's simple.

You put these under the pev->renderfx = kRenderFxGlowShell; line
pev->rendercolor.x = (NUMBER HERE);
pev->rendercolor.y = (NUMBER HERE);
pev->rendercolor.z = (NUMBER HERE);

These might look confusing, but they're just values for RGB color.
rendercolor.x is red
rendercolor.y is green
rendercolor.z is blue

For example,
pev->rendercolor.x = 255;
would make red glowshell:

pev->rendercolor.y = 255;
would make green glowshell:

pev->rendercolor.z = 255;
would make blue glowshell:

pev->rendercolor.x = 128;
pev->rendercolor.z = 128;
would make purple glowshell:

and so on.

Hope this tutorial helped. If you have any questions or if anything was unclear leave a comment or PM me.