Every lamp post, neon sign and steam vent in San Andreas carries 2DFX: small effect records baked into the model by RenderWare. They are what makes a streetlight glow and a manhole steam. MTA never exposed them.

Neon does, with 13 client functions that read, edit, add and remove those records.

The clip runs test-resources/2dfx-showcase. There is no custom DFF, TXD, shader or texture in it. The lamp posts are stock model 1226 and every texture name comes from GTA itself; the whole show is native 2DFX types driven from Lua.

The one thing to understand first

This API is model-level, not object-level. It matches GTA’s RenderWare 2DFX plugin, where the effect belongs to the model rather than to a placed instance.

Change a light on model 1226 and every lamp post using model 1226 changes. That is not a limitation to work around, it is the lever: the showcase splits its lamp posts across twelve runtime models so one Lua call drives five real lamp posts at once, and the two sides can run opposite colour waves.

If you need per-object effects, give the objects their own runtime models first.

The five effect types

Type	What it is	Properties
light	A corona, point light and shadow. The workhorse.	15, listed below
particle	A named native particle emitter	name only
roadsign	Up to four lines of generated text on a board	size, rotation, flags, color, text1 to text4
escalator	A moving escalator surface	bottom, top, end, direction
sun_glare	A sun glare sprite	none, position only

Light properties

All fifteen are required when adding a light:

Property	Type	Notes
drawDistance	float	Must be 0 or greater
lightRange	float	Point light radius, 0 or greater
coronaSize	float	0 or greater
shadowSize	float	0 or greater
shadowMultiplier	int	0 to 255
showMode	string	Blink behavior, see below
coronaReflection	bool	Wet-road reflection
flareType	int	0 or 1
flags	table	Effect flags
shadowDistance	int	-128 to 127
offset	Vector3	Each axis -128 to 127
color	color
coronaName	string	Texture name, cannot be empty
shadowName	string	Texture name, cannot be empty

showMode accepts default, on_off_at_5, warnlight, trafficlight, traincrosslight, random_flashing, random_at_wet_weather, at_rain_only and lines. These are GTA’s own blink modes, so a light can behave like a real traffic light without a Lua timer.

Adding and removing

addModel2DFX(1337, 0, 0, 1.2, "light", {
    drawDistance = 100, lightRange = 12, coronaSize = 1.5, shadowSize = 4,
    shadowMultiplier = 200, showMode = "trafficlight", coronaReflection = true,
    flareType = 0, flags = {}, shadowDistance = 0, offset = { 0, 0, 0 },
    color = tocolor(255, 60, 60), coronaName = "coronastar", shadowName = "shad_exp",
})

Function	Purpose
addModel2DFX	Add a resource-owned effect to a model
removeModel2DFX	Remove an effect, including an original GTA one
restoreModel2DFX	Put a removed original effect back
resetModel2DFXEffects	Roll a model back to its original state
getModel2DFXCount	Count effects, with or without custom ones
getModel2DFXType	Read one effect’s type
getModel2DFXEffects	Dump every effect on a model
getModel2DFXPosition / setModel2DFXPosition / resetModel2DFXPosition	Read, move and restore an effect’s position
getModel2DFXProperty / setModel2DFXProperty / resetModel2DFXProperty	Read, change and restore one property

getModel2DFXCount(model, false) counts only the model’s original effects, which is how a resource finds a native effect index to edit without tripping over its own additions.

Ownership and rollback

Custom effects belong to the resource that created them. Overrides and removals of original GTA effects are stacked per resource, so two resources touching the same model do not silently clobber each other, and stopping one rolls back only its own layer.

Stopping a resource removes its custom effects and undoes its overrides. The regression harness proves this the honest way: it deliberately leaves effects alive on exit, and the next run starts by asserting the previous run’s effects are gone.

Restreaming, and why it matters

Adding or removing an effect changes the model, so already-streamed instances need to be rebuilt before the change is visible. A targeted model restream is cheap. engineRestreamWorld() is global and causes a noticeable streaming hitch.

The showcase never calls it during the recorded timeline, and the regression harness deliberately excludes it from its automatic run and puts it behind an explicit command instead. Treat it as a setup-time tool, not something to call while players are moving.

Issue additions in sequence rather than while a model is still being rebuilt.

Limits

• Client-side only. No server element, no synchronization.
• Model IDs are 0 to 65535.
• Particle name holds 1 to 23 characters. Native storage is char[24], so 24 characters would leave no room for the terminator.
• Roadsign lines are at most 16 characters each, across text1 to text4.
• Light offset and shadowDistance are signed bytes, so -128 to 127.
• Effects are model-level, so there is no way to change one placed object without giving it its own model.

Verification

test-resources/2dfx-test prints PASS / FAIL / SKIP in chat and to outputDebugString. It covers resource-stop cleanup from a previous run, rejecting a missing flags field without crashing, rejecting 24-character particle names, adding light, particle and roadsign effects, custom property set/get/reset, getModel2DFXCount(model, false) excluding custom effects, modifying and resetting a native light on model 1226, and removing then restoring a native effect while waiting for the targeted restream to settle.

/2dfxrestream and /2dfxstress [count] cover the global restream path explicitly, up to 50 cycles, verifying the custom count and type stay stable.

test-resources/2dfx-showcase is the cinematic: about 60 lamp posts, 12 independently controlled model groups, native blink modes, live colour and corona mutations, particle gates, generated roadsign text and a sun-glare cluster. Neither resource is auto-deployed; copy them into the server resources directory first.

Implementation: 27e3972e7.