fix: restore DOTS-instanced material props and Unity 6000.5 shader compat

[eordano]

Three independent shader fixes, all surfaced by compiling the DOTS-instancing (*_INSTANCING_ON) variants that editor compiles skip and player builds do not. The first is a live bug on main today, independent of any Unity upgrade.

1. UNITY_ACCESS_DOTS_INSTANCED_PROP_FROM_MACRO no longer exists

Scene/URP/LitInput.hlsl and Scene/URP/UnlitInput.hlsl define every instanced material property through UNITY_ACCESS_DOTS_INSTANCED_PROP_FROM_MACRO(...). That macro is not defined anywhere in the URP we currently ship — the only references to it in the whole package tree are these two files. Unity removed it when the override-mode system landed; the surviving macro is

// com.unity.render-pipelines.core/ShaderLibrary/UnityDOTSInstancing.hlsl:154
#define UNITY_ACCESS_DOTS_INSTANCED_PROP(type, var) ( /* Compile-time branches */ \
UNITY_DOTS_INSTANCED_PROP_IS_OVERRIDE_ENABLED(var) ? LoadDOTSInstancedData_##type(UNITY_DOTS_INSTANCED_METADATA_NAME(type, var)) \
: UNITY_DOTS_INSTANCED_PROP_IS_OVERRIDE_REQUIRED(var) ? LoadDOTSInstancedDataOverridden_##type(UNITY_DOTS_INSTANCED_METADATA_NAME(type, var)) \
: ((type)0) )

It also takes a different argument: the bare property name, composing the metadata symbol itself via UNITY_DOTS_INSTANCED_METADATA_NAME. So the call sites move from (float4, Metadata__BaseColor) to (float4, _BaseColor) — the Metadata_ prefix is dropped, not just the macro renamed.

This is why it only shows up in player builds: nothing compiles those defines until UNITY_DOTS_INSTANCING_ENABLED is set.

Codegen is unchanged. Both predicates compare static const int values, so the ternaries fold at compile time and the emitted code is a single LoadDOTSInstancedData_##type(metadata) — exactly what the old spelling produced. No extra load, no runtime branch, no register pressure.

Why the plain macro and not _WITH_DEFAULT: the two differ only when the override mode is disabled, where plain yields ((type)0) and _WITH_DEFAULT yields the CBUFFER value. UNITY_DOTS_INSTANCED_PROP expands to ..._OVERRIDE_SUPPORTED unless UNITY_DOTS_INSTANCED_PROP_OVERRIDE_DISABLED_BY_DEFAULT is defined, and we never define it — so IS_OVERRIDE_ENABLED is true and the load branch is taken. Plain is correct here.

2. unity_ObjectToWorld -> GetObjectToWorldMatrix()

Four call sites across Avatar_CelShading_DepthNormalsPass, DCL_ToonHighlight and DCL_ToonOutline. GetObjectToWorldMatrix() is UNITY_MATRIX_M, which under BRG/DOTS instancing resolves to the instanced matrix instead of the raw builtin. Same matrix load, no added cost — a correctness fix for the instanced variants, where the builtin is not the right source.

3. DCL_ToonOutline instance ID plumbing

frag already called UNITY_SETUP_INSTANCE_ID(i) on a VertexOutput that never carried an instance ID. Adds UNITY_VERTEX_INPUT_INSTANCE_ID to the struct and UNITY_TRANSFER_INSTANCE_ID(v, o) in vert, completing a contract that was already half-written. Cost is one extra interpolator, and only under instancing — UNITY_VERTEX_INPUT_INSTANCE_ID compiles to nothing otherwise.

4. URP 17.5 LitInput collision (the 6000.5 item)

Unity 6000.5's URP added #include "LitInput.hlsl" to LitForwardPass.hlsl, pulling ShaderLibrary/SurfaceInput.hlsl into the one DCL translation unit that includes URP's real LitForwardPass (DCL_Toon ForwardLit) — colliding with DCL_ToonInput.hlsl (_BaseMap, Alpha, UnityPerMaterial members) and rendering avatars magenta.

Pre-claims URP's UNIVERSAL_LIT_INPUT_INCLUDED guard so the new self-include no-ops (the same guard-reuse pattern this repo already uses in Scene/URP/LitInput.hlsl), and inlines the parameterless IsSurfaceTypeTransparent() that 6000.5's LitForwardPass calls — under the real file's own guard, since Shaders/Utils/SurfaceType.hlsl does not exist in 6000.4's URP. With _Surface defined 0.0f it returns false, matching 6000.4 behaviour exactly.

Verification

Both editors, zero errors and zero shader errors:

• unity-explorer dev on Unity 6000.4.0f1 — editor and macOS player build
• unity-explorer #9392 on Unity 6000.5.4f1 — editor, macOS player build, and in-world visual check (avatars correctly toon-shaded)
• StandaloneWindows64 / d3d11 full player build on 6000.5.4f1 — 0 shader errors, 0 CS errors across 132k log lines, Explorer.exe produced. DCL_Toon ForwardLit, DCL/Scene, and all DOTS-instancing variants compiled clean.

[github-actions]

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