Unity rules reference

A material on a Built-in shader in a URP/HDRP project renders pink and isn't SRP-batched. The reverse — an SRP shader on Built-in — fails the same way.

The shader reference is None or points at an asset that no longer exists — a deleted shader, or one from a package that isn't installed in this project.

Decompress On Load expands the whole clip to PCM in RAM at load. Past a few seconds, Compressed In Memory is almost always the better trade.

Compression Format: PCM is the largest option on disk and in memory. Vorbis is the sane default; ADPCM is the middle ground for short, frequent SFX.

Debug.Log isn't stripped from release builds, and the string is built whether or not anyone reads it. [Conditional] is how you actually remove the calls.

Read/Write Enabled on a model keeps mesh data in CPU memory as well as GPU memory. Unless something modifies the mesh at runtime, that's double memory.

Static Batching bakes a merged copy of every batched renderer's geometry: a real CPU win and a real memory bill, and the build-size half is easy to miss.

Read/Write Enabled keeps a full CPU-side copy alongside the GPU one, doubling a texture's memory. When you need it, and how to find the ones that don't.

Compression: None ships raw RGBA — several times the memory and build size of a block-compressed equivalent. How to find them and what to switch to.

You set Compressed, Unity imported RGBA32. ETC2 needs dimensions divisible by 4 and PVRTC square power-of-two — miss those and the importer falls back silently.

Under URP or HDRP, Enable GPU Instancing takes the material off the SRP Batcher path. For most scenes that's a net loss — the opposite of the intent.

Static Batching takes priority over GPU Instancing, so ticking Enable GPU Instancing everywhere is inert on static geometry — and worse than inert under an SRP.

SkinnedMeshRenderers are drawn individually, so instancing a material only skinned meshes use does nothing — and under an SRP it costs you the SRP Batcher too.

A clip over half a minute — music, ambience, long VO — belongs on Streaming, where Unity keeps a small buffer instead of the whole thing in memory.

Mesh Compression quantizes vertex data at import to shrink the build. It's lossy, so it's off by default — but on most props, Low is invisible.

A 4096×4096 texture costs 16× the memory of a 1024. Max Size caps it per platform at import without touching the source art — here's how to decide where.

UI sprites are drawn at a fixed screen scale, so their mip chain is never sampled — but it still costs about a third of the texture's memory.

Mipmap streaming loads only the mip levels the cameras need. With it off and a large eligible pool in the scene, that memory is resident for no reason.

Mipmap streaming needs both halves: the per-texture flag and the Quality Settings switch. With the switch off, the flags do nothing at all.

Unity's 'variants total' is the full keyword space, not what ships — but it's still the number that predicts shader import and build-compile time.

Implicit dependencies are duplicated per group. Unity's Analyze rule finds them; the work is deciding which ones matter and extracting them safely.

Classic AssetBundles copy an unassigned shared asset into every bundle that references it — the same waste as Addressables, with no Analyze window to see it.

The same texture imported into three folders is three GUIDs and three copies in the build. Finding them is a hash; fixing them means redirecting refs first.

An asset no build scene, Resources folder, project setting or bundle assignment can reach is probably dead weight — 'probably' being the careful word.

Shaders written for an older Unity break on include paths and macros after an upgrade, and every material using them renders magenta. Unity logs it at import.

It isn't a straight rename: FindAnyObjectByType and FindFirstObjectByType differ on whether order is guaranteed, and the faster one fits most call sites.

Under 'Input System Package (New)', every old UnityEngine.Input call throws InvalidOperationException at runtime. It compiles fine, so nothing warns you first.

The package's own manifest declares a minimum Unity version above your editor's. That's not a heuristic — it's the package telling you it isn't supported here.

For a web build, download size is load time. Brotli cuts the .wasm and .data payload substantially, and Disabled is the one setting here that's a pure loss.

IL2CPP compiles unused managed code into your build. Stripping removes it; the reason it's ever off is reflection, and link.xml is the right fix for that.