Chapter 6.5: Post-Process Effects (PPE)

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Introduction

DayZ's Post-Process Effects (PPE) system controls visual effects applied after scene rendering: blur, color grading, vignette, chromatic aberration, night vision, and more. The system is built around PPERequester classes that can request specific visual effects. Multiple requesters can be active simultaneously, and the engine blends their contributions. This chapter covers how to use the PPE system in mods.

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Architecture Overview

PPEManager
├── PPERequesterBank              // Static registry of all available requesters
│   ├── REQ_INVENTORYBLUR         // Inventory blur
│   ├── REQ_MENUEFFECTS           // Menu effects
│   ├── REQ_CONTROLLERDISCONNECT  // Controller disconnect overlay
│   ├── REQ_UNCONSCIOUS           // Unconsciousness effect
│   ├── REQ_FEVEREFFECTS          // Fever visual effects
│   ├── REQ_FLASHBANGEFFECTS      // Flashbang
│   ├── REQ_BURLAPSACK            // Burlap sack on head
│   ├── REQ_DEATHEFFECTS          // Death screen
│   ├── REQ_BLOODLOSS             // Blood loss desaturation
│   └── ... (many more)
└── PPERequester_*                // Individual requester implementations

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PPEManager

The PPEManager is a singleton that coordinates all active PPE requests. You rarely interact with it directly --- instead, you work through PPERequester subclasses.

// Get the manager instance
PPEManager GetPPEManager();

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PPERequesterBank

File: 3_Game/PPE/pperequesterbank.c

A static registry that holds instances of all PPE requesters. Access specific requesters by their constant index.

Getting a Requester

// Get a requester by its bank constant
PPERequester req = PPERequesterBank.GetRequester(PPERequesterBank.REQ_INVENTORYBLUR);

Common Requester Constants

Constant	Effect
REQ_INVENTORYBLUR	Gaussian blur when inventory is open
REQ_MENUEFFECTS	Menu background blur
REQ_UNCONSCIOUS	Unconsciousness visual (blur + desaturation)
REQ_DEATHEFFECTS	Death screen (grayscale + vignette)
REQ_BLOODLOSS	Blood loss desaturation
REQ_FEVEREFFECTS	Fever chromatic aberration
REQ_FLASHBANGEFFECTS	Flashbang whiteout
REQ_BURLAPSACK	Burlap sack blindfold
REQ_PAINBLUR	Pain blur effect
REQ_CONTROLLERDISCONNECT	Controller disconnect overlay
REQ_CAMERANV	Night vision
REQ_FILMGRAINEFFECTS	Film grain overlay
REQ_RAINEFFECTS	Rain screen effects
REQ_COLORSETTING	Color correction settings

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PPERequester Base

All PPE requesters extend PPERequester:

class PPERequester : Managed
{
    // Start the effect
    void Start(Param par = null);

    // Stop the effect
    void Stop(Param par = null);

    // Check if active
    bool IsActiveRequester();

    // Set values on material parameters
    void SetTargetValueFloat(int mat_id, int param_idx, bool relative,
                              float val, int priority_layer, int operator = PPOperators.SET);
    void SetTargetValueColor(int mat_id, int param_idx, bool relative,
                              float val1, float val2, float val3, float val4,
                              int priority_layer, int operator = PPOperators.SET);
    void SetTargetValueBool(int mat_id, int param_idx, bool relative,
                             bool val, int priority_layer, int operator = PPOperators.SET);
    void SetTargetValueInt(int mat_id, int param_idx, bool relative,
                            int val, int priority_layer, int operator = PPOperators.SET);
}

PPOperators

class PPOperators
{
    static const int SET          = 0;  // Directly set the value
    static const int ADD          = 1;  // Add to current value
    static const int ADD_RELATIVE = 2;  // Add relative to current
    static const int HIGHEST      = 3;  // Use the highest of current and new
    static const int LOWEST       = 4;  // Use the lowest of current and new
    static const int MULTIPLY     = 5;  // Multiply current value
    static const int OVERRIDE     = 6;  // Force override
}

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Common PPE Material IDs

Effects target specific post-processing materials. Common material IDs:

Constant	Material
PostProcessEffectType.Glow	Bloom / glow
PostProcessEffectType.FilmGrain	Film grain
PostProcessEffectType.RadialBlur	Radial blur
PostProcessEffectType.ChromAber	Chromatic aberration
PostProcessEffectType.WetEffect	Wet lens effect
PostProcessEffectType.ColorGrading	Color grading / LUT
PostProcessEffectType.DepthOfField	Depth of field
PostProcessEffectType.SSAO	Screen-space ambient occlusion
PostProcessEffectType.GodRays	Volumetric light
PostProcessEffectType.Rain	Rain on screen
PostProcessEffectType.Vignette	Vignette overlay
PostProcessEffectType.HBAO	Horizon-based ambient occlusion

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Using Built-in Requesters

Inventory Blur

The simplest example --- the blur that appears when the inventory opens:

// Start blur
PPERequester blurReq = PPERequesterBank.GetRequester(PPERequesterBank.REQ_INVENTORYBLUR);
blurReq.Start();

// Stop blur
blurReq.Stop();

Flashbang Effect

PPERequester flashReq = PPERequesterBank.GetRequester(PPERequesterBank.REQ_FLASHBANGEFFECTS);
flashReq.Start();

// Stop after a delay
GetGame().GetCallQueue(CALL_CATEGORY_GAMEPLAY).CallLater(StopFlashbang, 3000, false);

void StopFlashbang()
{
    PPERequester flashReq = PPERequesterBank.GetRequester(PPERequesterBank.REQ_FLASHBANGEFFECTS);
    flashReq.Stop();
}

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Creating a Custom PPE Requester

To create custom post-process effects, extend PPERequester and register it.

Step 1: Define the Requester

class MyCustomPPERequester extends PPERequester
{
    override protected void OnStart(Param par = null)
    {
        super.OnStart(par);

        // Apply a strong vignette
        SetTargetValueFloat(PostProcessEffectType.Glow, PPEGlow.PARAM_VIGNETTE,
                            false, 0.8, PPEManager.L_0_STATIC, PPOperators.SET);

        // Desaturate colors
        SetTargetValueFloat(PostProcessEffectType.ColorGrading, PPEColorGrading.PARAM_SATURATION,
                            false, 0.3, PPEManager.L_0_STATIC, PPOperators.SET);
    }

    override protected void OnStop(Param par = null)
    {
        super.OnStop(par);

        // Reset to defaults
        SetTargetValueFloat(PostProcessEffectType.Glow, PPEGlow.PARAM_VIGNETTE,
                            false, 0.0, PPEManager.L_0_STATIC, PPOperators.SET);
        SetTargetValueFloat(PostProcessEffectType.ColorGrading, PPEColorGrading.PARAM_SATURATION,
                            false, 1.0, PPEManager.L_0_STATIC, PPOperators.SET);
    }
}

Step 2: Register and Use

Registration is handled by adding the requester to the bank. In practice, most modders use the built-in requesters and modify their parameters rather than creating fully custom ones.

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Night Vision (NVG)

Night vision is implemented as a PPE effect. The relevant requester is REQ_CAMERANV:

// Enable NVG effect
PPERequester nvgReq = PPERequesterBank.GetRequester(PPERequesterBank.REQ_CAMERANV);
nvgReq.Start();

// Disable NVG effect
nvgReq.Stop();

The actual NVG in-game is triggered by the NVGoggles item through its ComponentEnergyManager and the NVGoggles.ToggleNVG() method, which internally drives the PPE system.

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Color Grading

Color grading modifies the overall color appearance of the scene:

PPERequester colorReq = PPERequesterBank.GetRequester(PPERequesterBank.REQ_COLORSETTING);
colorReq.Start();

// Adjust saturation (1.0 = normal, 0.0 = grayscale, >1.0 = oversaturated)
colorReq.SetTargetValueFloat(PostProcessEffectType.ColorGrading,
                              PPEColorGrading.PARAM_SATURATION,
                              false, 0.5, PPEManager.L_0_STATIC,
                              PPOperators.SET);

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Blur Effects

Gaussian Blur

PPERequester blurReq = PPERequesterBank.GetRequester(PPERequesterBank.REQ_INVENTORYBLUR);
blurReq.Start();

// Adjust blur intensity (0.0 = none, higher = more blur)
blurReq.SetTargetValueFloat(PostProcessEffectType.GaussFilter,
                             PPEGaussFilter.PARAM_INTENSITY,
                             false, 0.5, PPEManager.L_0_STATIC,
                             PPOperators.SET);

Radial Blur

PPERequester req = PPERequesterBank.GetRequester(PPERequesterBank.REQ_PAINBLUR);
req.Start();

req.SetTargetValueFloat(PostProcessEffectType.RadialBlur,
                         PPERadialBlur.PARAM_POWERX,
                         false, 0.3, PPEManager.L_0_STATIC,
                         PPOperators.SET);

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Priority Layers

When multiple requesters modify the same parameter, the priority layer determines which one wins:

class PPEManager
{
    static const int L_0_STATIC   = 0;   // Lowest priority (static effects)
    static const int L_1_VALUES   = 1;   // Dynamic value changes
    static const int L_2_SCRIPTS  = 2;   // Script-driven effects
    static const int L_3_EFFECTS  = 3;   // Gameplay effects
    static const int L_4_OVERLAY  = 4;   // Overlay effects
    static const int L_LAST       = 100;  // Highest priority (override all)
}

Higher numbers take priority. Use PPEManager.L_LAST to force your effect to override all others.

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Summary

Concept	Key Point
Access	PPERequesterBank.GetRequester(CONSTANT)
Start/Stop	requester.Start() / requester.Stop()
Parameters	SetTargetValueFloat(material, param, relative, value, layer, operator)
Operators	PPOperators.SET, ADD, MULTIPLY, HIGHEST, LOWEST, OVERRIDE
Common effects	Blur, vignette, saturation, NVG, flashbang, grain, chromatic aberration
NVG	REQ_CAMERANV requester
Priority	Layers 0-100; higher number wins conflicts
Custom	Extend PPERequester, override OnStart() / OnStop()

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Best Practices

• Always call Stop() to clean up your requester. Failing to stop a PPE requester leaves its visual effect permanently active, even after the triggering condition ends.
• Use appropriate priority layers. Gameplay effects should use L_3_EFFECTS or higher. Using L_LAST (100) overrides everything including vanilla unconsciousness and death effects, which can break the player experience.
• Prefer built-in requesters over custom ones. The PPERequesterBank already contains requesters for blur, desaturation, vignette, and grain. Reuse them with adjusted parameters before creating a custom requester class.
• Test PPE effects under different lighting conditions. Vignette and desaturation look drastically different at night vs daytime. Verify your effect reads well in both extremes.
• Avoid stacking multiple high-intensity blur effects. Multiple active blur requesters compound, potentially rendering the screen unreadable. Check IsActiveRequester() before starting additional effects.

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Compatibility & Impact

• Multi-Mod: Multiple mods can activate PPE requesters simultaneously. The engine blends them using priority layers and operators. Conflicts occur when two mods use the same priority level with PPOperators.SET on the same parameter -- the last to write wins.
• Performance: PPE effects are GPU-bound post-processing passes. Enabling many simultaneous effects (blur + grain + chromatic aberration + vignette) can reduce frame rate on lower-end GPUs. Keep active effects minimal.
• Server/Client: PPE is entirely client-side rendering. The server has no knowledge of post-process effects. Never condition server logic on PPE state.

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