Muzzle Flash Lighting

This tutorial will show you how to create a muzzleflash that dynamically appears and lights up the world around the player, like in Counter-Strike: Source. These types of lights are called "dlights".

This code was designed for any Orange Box based mod, singleplayer or multiplayer. It also works with NPCs, assuming they work properly.

Warning: Some dynamic props will not be lit when using dlights.

Warning: Too many dlights may result in severe performance losses on low-end systems. When coding for lighting, dlights should be used sparingly.

Note: The quality of dynamic lights depends on the lightmap scale.

Implementing Dlight-based Muzzleflashes

The coding begins! Only a few minor changes are needed here to make muzzleflashes look better than ever.

First off, open up c_baseanimating.cpp and search for the function void C_BaseAnimating::ProcessMuzzleFlashEvent()

Vector vAttachment;
QAngle dummyAngles;
GetAttachment( attachment, vAttachment, dummyAngles );

// Make an elight
dlight_t *el = effects->CL_AllocElight( LIGHT_INDEX_MUZZLEFLASH + index );
el->origin = vAttachment;
el->radius = random->RandomInt( 32, 64 ); 
el->decay = el->radius / 0.05f;
el->die = gpGlobals->curtime + 0.05f;
el->color.r = 255;
el->color.g = 192;
el->color.b = 64;
el->color.exponent = 5;

Valve went a little crazy here and the result was a seemingly ugly muzzleflash. This tutorial is all about making things pretty, so lets change that. Replace the entries above with this:

			Vector vAttachment, vAng;
			QAngle angles;
			GetAttachment(1, vAttachment, angles); // set 1 instead of "attachment"
			AngleVectors(angles, &vAng);
			vAttachment += vAng * 2;

			dlight_t *dl = effects->CL_AllocDlight(index);
			dl->origin = vAttachment;

			// Original color values
			int originalR = 231;
			int originalG = 219;
			int originalB = 14;

			// Randomize color components within the range of +/- 20
			dl->color.r = originalR + random->RandomInt(-20, 20);
			dl->color.g = originalG + random->RandomInt(-20, 20);
			dl->color.b = originalB + random->RandomInt(0, 0);

			// Randomize the die value by +/- 0.01
			dl->die = gpGlobals->curtime + 0.05f + random->RandomFloat(-0.01f, 0.01f);
			dl->radius = random->RandomFloat(245.0f, 256.0f);

			// Randomize the decay value
			dl->decay = random->RandomFloat(400.0f, 600.0f);

Tip: You can try 252, 238, 128 for a realistic washed out yellow color.

Idea: Write a console command to enable or disable dlights to shave off performance losses