UE5-Modular-Game-Framework/docs/blueprints/17-capture/144_M_CaptureSurface_Master.md

144 — Capture Surface Master Material (M_CaptureSurface_Master)

Purpose

Single master material for ALL capture surface modes (mirror, portal, monitor, horror, fake window). All features are parameter-driven — inactive features have zero rendering cost.

Dependencies

• Requires: MPC_CaptureSurface (145) for global scalar parameters
• Required By: All capture surface actors (139-143) via their material instances
• Engine/Plugin Requirements: None

Class Info

Property	Value
Material Domain	Surface
Blend Mode	Opaque
Shading Model	Unlit
Asset Path	Content/Framework/Capture/M_CaptureSurface_Master.uasset
C++ Status	N/A (Material asset)
Asset to Create	Material in UE5 editor

1. Material Layer Stack (9 Layers)

Layer 0: Render Target Sample

Texture Sample (parameter: "CaptureTexture", TextureRenderTarget2D)
  ├─ UVs: If Mirror mode → UV * (1, -1) + (0, 1)  [flip vertically for mirror reflection]
  │        If Portal/Monitor mode → straight UVs
  └─ Output → Base Color input of Layer 1

Switch: StaticSwitchParameter: bIsMirror (true = UV flip, false = straight)

Layer 1: Condensation UV Distortion

Condensation Normal Map (Texture Sample, parameter: "CondensationNormal")
  ├─ UVs: Panner (slow drift, driven by Time * CondensationFlow MPC param)
  ├─ Normal strength: DistortionAmplitude MPC param
  └─ Output: Modified UVs for Layer 0's texture sample

Note: Layer 1 modifies the UVs of Layer 0, not its color.

Layer 2: Fresnel Edge Fade

Fresnel node (Exponent = 2.0, BaseReflectFraction = 0.0)
  ├─ Dot product: CameraVector · VertexNormal
  └─ Output: Opacity mask for edge darkening (subtle vignette)

Layer 3: Dirt / Scratch Multiply

Dirt Mask (Texture Sample, parameter: "DirtMask")
  ├─ Multiply with DirtOpacity MPC param
  ├─ Lerp: Clean RT ←→ Dirty RT using DirtOpacity
  └─ Tint: Mix with SurfaceAge MPC param (yellowing/oxidation)

Layer 4: Steam / Fog Lerp

Animated Noise (Procedural noise, tiling, scrolling via Time)
  ├─ SteamIntensity MPC param → controls noise opacity
  ├─ Lerp: Clear view ←→ Fogged view
  └─ Output: blended base color

Layer 5: Steam Emissive Glow

Steam mask (same noise as Layer 4, separate brightness)
  ├─ Multiply by SteamEmissiveIntensity MPC param
  ├─ Color: Soft warm white (backlit fog look)
  └─ Output → Emissive Color pin

Layer 6: Text Reveal Mask

Text Mask (Texture Sample, parameter: "TextRevealMask")
  ├─ Reveal progress: TextRevealProgress MPC param (0→1 wipe)
  ├─ Blend with steam carrier (appears as text IN the steam)
  └─ Output: emissive text overlay (optional) or color replacement

Layer 7: Mirror Darkness Multiply

MirrorDarkness MPC param (0.0 = normal, 1.0 = black)
  ├─ Multiply base color by (1.0 - MirrorDarkness)
  └─ Output: darkened reflection

Layer 8: Wrong Reflection Crossfade

Second RT Input (parameter: "DelayedCaptureTexture" OR separate RT)
  ├─ Lerp: Current_RT ←→ Delayed/Wrong_RT using WrongReflectionBlend MPC param
  └─ Final Output → Emissive Color (Unlit material)

2. Material Parameters (Exposed)

Texture Parameters

Name	Type	Default	Description
CaptureTexture	TextureRenderTarget2D	—	Live capture render target
CondensationNormal	Texture2D	T_DefaultNormal	Condensation flow normal map
DirtMask	Texture2D	T_DefaultWhite	Dirt/scratch mask texture
TextRevealMask	Texture2D	T_DefaultBlack	Steam text mask

Scalar Parameters (Driven by MPC)

Name	Default	Description
SteamIntensity	0.0	Steam fog opacity
DirtOpacity	0.0	Dirt/scratch opacity
CondensationFlow	0.0	Condensation normal scroll speed
DistortionAmplitude	0.0	UV distortion magnitude
MirrorDarkness	0.0	Mirror darkening
WrongReflectionBlend	0.0	Wrong reflection crossfade
TextRevealProgress	0.0	Steam text reveal progress
SteamEmissiveIntensity	0.0	Steam glow brightness
DelayedReflectionBlend	0.0	Delayed frame blend
SurfaceAge	0.0	Oxidation/yellowing tint

Static Switch Parameters

Name	Default	Description
bIsMirror	true	Enable vertical UV flip for mirror mode
bEnableHorrorLayers	false	Enable Layers 6-8 (text reveal, darkness, wrong reflection)

3. MPC Binding

All 10 scalar parameters are NOT material-instance parameters — they are driven by MPC_CaptureSurface (145) at runtime. The C++ component calls PushMPCParameters() each frame to update these values globally.

In the material: use Collection Parameter nodes referencing MPC_CaptureSurface for each of the 10 scalars listed above.

4. Manual Implementation Guide

4.1 Create Master Material

1. Create Material: Name = M_CaptureSurface_Master
2. Set Material Domain = Surface, Blend Mode = Opaque, Shading Model = Unlit
3. Build Layer 0: Texture Sample Parameter node named "CaptureTexture"
4. Add Static Switch: "bIsMirror" → UV flip branch (Custom UV × (1,-1) + (0,1))
5. Build Layers 1-8 as described above
6. Connect final color → Emissive Color (Unlit output)

4.2 MPC Integration

1. Create Collection Parameter nodes for each of the 10 MPC scalars
2. Set the Collection asset to MPC_CaptureSurface
3. Set the Parameter Name to match each MPC entry (e.g., "SteamIntensity")

4.3 Performance

• Use StaticSwitchParameter for bEnableHorrorLayers — when false, Layers 6-8 are compiled out (zero cost)
• Condensation normal Layer 1 is cheap (one texture sample + panner)
• All MPC reads are free (constant buffer lookup)

5. Build Checklist

• Create M_CaptureSurface_Master material in UE5 editor
• Set Domain=Surface, Blend=Opaque, Shading=Unlit
• Build all 9 layers (verify material compiles)
• Add 10 MPC Collection Parameter nodes
• Add bIsMirror and bEnableHorrorLayers static switches
• Compile material — no errors
• Create MI instances and verify parameter override works