PostFx Turbulence Effect

Screen-space turbulence distortion post-processing effect. Applies a heat-haze or ripple distortion to the back buffer.

Overview

Declarative setup script (no M module). Registers:

• PFX_TurbulenceStateBlock - Z-disabled, linear clamp sampler
• PFX_TurbulenceShader - Turbulence distortion pixel shader
• TurbulenceFx - PostEffect (disabled by default, priority 0.5)

Scene Objects

Configuration

-- Turbulence renders after glow objects but before other post effects
turbulenceFx:setField("renderTime", 0, "PFXAfterBin")
turbulenceFx:setField("renderBin", 0, "GlowBin")
turbulenceFx.renderPriority = 0.5  -- Renders after the glows themselves

Notes

• Unlike most PostFx effects, this one allows reflection passes (allowReflectPass = true)
• Renders after GlowBin with priority 0.5 (after glow at priority 1)
• Z-buffer testing and writing are both disabled
• Reads from $backBuffer
• The effect is disabled by default and must be explicitly enabled

Usage Example

-- Enable turbulence effect (e.g., near heat sources)
local turbFx = scenetree.findObject("TurbulenceFx")
if turbFx then turbFx:enable() end

See Also

• PostFx Glow - Glow/bloom (shares GlowBin)
• PostFx Flash - Screen flash overlay