texture-formats-tier2

Requesting texture-formats-tier2 also enables tier 1 and allows GPUStorageTextureAccess of "read-write" on an additional set of formats. Examples include rgba8unorm, r16float, rgba16float, and rgba32float. The list is selective: it does not include every format introduced or extended by tier 1.

This is useful for compute image processing and simulation passes that need to load a texel and then update it through the same storage binding. The matching WGSL declaration uses read_write, which requires browser support for readonly_and_readwrite_storage_textures. The shader declaration, texture format, usage flags, and bind-group layout must all agree.

Read-write access is not an atomic read-modify-write operation. Concurrent invocations updating the same texel can race, and a workgroup barrier cannot coordinate separate workgroups. Design ownership and pass boundaries explicitly. Without tier 2, use core r32float, r32uint, or r32sint where appropriate, or separate input and output textures across passes.