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Mirror Cubemap Mod (Watch_Dogs 1)

Recipe proven by: Stethri's Nexus mod "Nikki's Bathroom Mirror Fix" (verified byte-level, then independently reproduced with the official converter). Shader analysis guidance: Parallellines.

Cross-reference: full format spec → Material Binary Format; installing loose mod files → installpackage-over-patch; texture repacking → XBT Texture Format

Background: How DriverGeneric Does Reflections​

Most world geometry in WD1 uses the DriverGeneric mesh shader. Its reflection path is fully data-driven from the material:

  • The material descriptor (engine/shaders/materialdescriptors/drivergeneric.xml) declares:
<parameter name="ReflectionTexture" type="samplerCUBE" platform="PC,DURANGO,ORBIS" />
  • mesh_drivergeneric.fx binds it as a cubemap:
PROVIDER_TEXTURE_DECLARE( DECLARE_TEXCUBE, MaterialDriverGeneric, _ReflectionTexture );

and the CUSTOM_REFLECTION variant samples it with a glossiness-scaled LOD plus a Fresnel term derived from the material's Reflectance:

float3 reflectionVector = reflect( cameraToVertexWS, normal );
reflectionTexture = texCUBElod( ReflectionTexture,
float4( reflectionVector, glossiness * -MaxStaticReflectionMipIndex + MaxStaticReflectionMipIndex ) );
  • In the G-buffer pass, CUSTOM_REFLECTION (and MATCAP) set gbuffer.isReflectionDynamic = false and gbuffer.isDeferredReflectionOn = false, then hand the cubemap straight to the lighting pass — i.e. the engine skips its dynamic probe machinery entirely and uses your static cubemap.

So: give the material a ReflectionType that enables the static-cubemap path and a ReflectionTexture pointing at any cubemap XBT, and the surface becomes reflective.

ReflectionType Values Observed​

ValueBehaviorStatus
0No custom reflection (engine probes / none)retail default
1Not cleanly tested on DriverGenericunverified
2Static cubemap reflection from ReflectionTexture✅ verified

Caveat: semantics are per-shader. Unlit-shader materials ship ReflectionType=1 + ReflectionTexture=citycubemap.xbt (e.g. the sdore2-m-* road materials) and work fine — there's no evidence value 1 is inherently bad; it simply isn't part of the verified recipe here. Stick to value 2 on DriverGeneric.

The Recipe — Exactly Two Changes​

Example material: graphics/_materials/adolbec-m-2013070356157858.material.bin (name NH_Bathroom_Mirror, shader DriverGeneric, 48 params retail).

  1. ReflectionType: 0 → 2
  2. Insert a new string param ReflectionTexture (type 8) pointing at a cubemap, e.g. graphics\_textures\cubemap\nh_bathroom_01_d.xbt — immediately after the ReflectionType elem.

That's it. Resulting XML fragment:

<Elem>
 <type>5</type>
 <unk1>0</unk1>
 <name>ReflectionType</name>
 <Value>2</Value>
</Elem>
<Elem>
 <type>8</type>
 <unk1>0</unk1>
 <name>ReflectionTexture</name>
 <Value>graphics\_textures\cubemap\nh_bathroom_01_d.xbt</Value>
</Elem>

Leave untouched​

  • DiffuseTexture1
  • Reflectance
  • WetReflectance

This is a minimal-diff principle, not a safety claim: the proven-working mod changes only ReflectionType + adds ReflectionTexture, so those are the only changes validated end-to-end. A mirror-approach freeze we hit earlier turned out to be a symptom of an invalid material file (hand-built binary with wrong encoding) — not of any particular parameter value. If the material parses, parameter tweaks like reflectance are fair game; the recipe above just stays minimal because it's what's proven.

Order matters​

The new ReflectionTexture elem goes right after ReflectionType, not appended at the end of the command list. Parameter order is part of the file contract (see Material Binary Format).

Step by Step with ConvertMaterials.exe​

Prereqs: ConvertMaterials.exe + SDL2.dll + res/ (the Disrupt Editor standalone converter), wine installed, the target .material.bin extracted from the archives, and a cubemap .xbt.

cd /path/to/convert_materials # run from the exe directory!

# 1. unpack side: convert retail BIN → XML
cp /extracted/adolbec-m-….material.bin work.material.bin
wine ConvertMaterials.exe work.material.bin # writes work.material.bin.xml

# 2. edit work.material.bin.xml:
# ReflectionType Value 0 → 2, insert ReflectionTexture elem after it (above)

# 3. pack side: convert edited XML → BIN
wine ConvertMaterials.exe work.material.bin.xml # rewrites work.material.bin

# sanity check
ls -la work.material.bin # ~1056 bytes for this material (1008 + 48)

Sanity-check expectations for this material: output grows by exactly one string param (+48 bytes: header/type/hash/length/path), round-trip of the unedited file differs only in 4 header bytes.

Packaging the Mod​

Loose-file layout (works with the installpackage trick or a mod loader's workspace mount):

workspace/
├── graphics/
│ ├── _materials/
│ │ └── adolbec-m-2013070356157858.material.bin # edited
│ └── _textures/
│ └── cubemap/
│ └── nh_bathroom_01_d.xbt # your cubemap asset

Mirror the same relative paths under whichever install route you use — see installpackage-over-patch for the DLL hex edit that makes the game load loose installpackage/ files without repacking the patch archive.

Cubemap Assets You Can Point At​

  • WD1 global fallback: graphics/_textures/cubemap/citycubemap.xbt — already shipped with every WD1 install (used by the Unlit road materials), so it needs no extra asset file.
  • WDL parallax probes: Watch Dogs: Legion ships per-location probes as worlds/london/localcubemaps/{GUID}_{color|depth|normal}.xbt.
  • Any cubemap XBT works — bake or convert your own via the usual XBT tooling. A bathroom-appropriate cubemap (like Stethri's nh_bathroom_01_d.xbt) sells the effect far better than a generic city sky.

Applying World-Wide (Batch Notes)​

To fix every mirror instead of one:

  1. Enumerate all .material.bin files from the unpacked archives.
  2. For each: BIN → XML, then detect candidates — has a ReflectionType elem (value 0), low/unset reflection params, and mirror-ish names/materials.
  3. Apply the two-change recipe; XML → BIN; stage into the mod workspace preserving archive paths.
  4. Game-test each batch before mass deployment. The freeze failure mode is silent at build time — only loading the area proves the file is good.

Keep the batch script driving ConvertMaterials.exe (not a hand-rolled serializer) — see the warning in Material Binary Format.

Credits​

  • Stethri — Nexus mod that proved the approach end-to-end.
  • Parallellines — shader guidance.
  • Disrupt Editor converter (ConvertMaterials.exe) by j301scott.