Env quadraticbeam

This entity is not in the FGD by default.
It should not be put directly in a map because it is only configurable via code or vscript.

Class hierarchy
CEnvQuadraticBeam ↳CPointEntity ↳CBaseEntity
effects.cpp

Class hierarchy (client)
C_QuadraticBeam ↳C_BaseEntity
c_effects.cpp

env_quadraticbeam is an entity available in all Source games. It is a duplicate of the beam entity, but with ability to arc by using a quadratic equation. It can be used to produce a similar effect to the physics gun. The formula used to form the curve can be found here.

Important:This entity has no additional KIO other than those that CBaseEntity already offers! Values listed under 'Fields' can only be accessed with an external plugin, or the NetProp manager found in certain VScript-supported titles ( and ).

Bug:Disappears if the end and control positions are outside the player's view field.  (tested in: )

Fields

m_targetPosition <FIELD_POSITION_VECTOR>

END point

m_controlPosition <FIELD_POSITION_VECTOR>

CONTROL point (see picture)

m_scrollRate <FIELD_FLOAT>

Must be value between -4, 4

m_flWidth <FIELD_FLOAT>

Notable KIO

Note:The CBaseEntity model keyvalue does not work for setting the sprite, it must be set after spawning.

Keyvalues

Origin (origin) <vector>

Start point of the beam

Inputs

Color <color255RedirectInput/color32>

Changes color

Spawning via vscript example

function SpawnQuadBeam(start, end, control, color="255 0 0", model="sprites/laserbeam.spr") {

    // precache the beam sprite
    if (!IsModelPrecached(model))
        PrecacheModel(model)

    // spawn the beam and set the start point
    local ent = SpawnEntityFromTable("env_quadraticbeam", {
        origin = start
    //  model = model //model doesn't work here, need to SetModel after spawning
    })

    // set the beam sprite
    ent.SetModel(model)

    // set the end point for the beam
    NetProps.SetPropVector(ent, "m_targetPosition", end)

    // set the control point for the curve
    NetProps.SetPropVector(ent, "m_controlPosition", control)

    NetProps.SetPropFloat(ent, "m_scrollRate", 2)
    NetProps.SetPropFloat(ent, "m_flWidth", 5)

    // set the beam color
    DoEntFire("!self", "color", color, 0, null, ent)
}

//Draw a beam from the players origin point to the nearest prop_dynamic in a 2048hu radius
local start_pos = GetListenServerHost().GetOrigin()
local end_pos = Entities.FindByClassnameNearest("prop_dynamic", start_pos, 2048).GetOrigin()

//set control point to map origin (0 0 0)
local control_pos = Vector()

SpawnQuadBeam(start_pos, end_pos, control_pos)

See Also

• Left_4_Dead_2/Script_Functions#CNetPropManager
• Team_Fortress_2/Scripting/Script_Functions#CNetPropManager
• beam
• env_beam