There are signals, but indirectly. Developers have requested having access
to early-z-test (
https://github.com/gpuweb/gpuweb/issues/4891#issuecomment-3341897141). But,
if you write to the `frag_depth` it will disable the early-z test. Adding
the `less` or `greater` attribute allows the fragment shader to write to
the fragment depth, while maintaining the early-z optimization because the
shader knows you're only writing in the depth in a given direction.

So, while developers did not specifically comment on this, it is a
component of providing a comprehensive early-z feature in the future.

dan


On Mon, Aug 24, 2026 at 2:54 PM Alex Russell <[email protected]>
wrote:

> Are there really no signals from developers? Is nobody asking for this?
>
> On Monday, August 24, 2026 at 9:03:33 AM UTC-7 Chromestatus wrote:
>
>> *Contact emails*
>> [email protected]
>>
>> *Explainer*
>> https://github.com/gpuweb/gpuweb/blob/main/proposals/fragment-depth.md
>>
>> *Specification*
>> https://github.com/gpuweb/gpuweb/pull/6299
>>
>> *Summary*
>> Adds the ability to provide a `less` or `greater` modifier to the
>> `@builtin(frag_depth)` in WGSL. The current `@builtin(frag_depth)` can
>> potentially introduce a performance penalty due to disabling the early-Z
>> optimizations on a draw call. The new modifiers allow the explicit setting
>> of the buffer mode and allow the early-Z optimizations to be applied.
>>
>> *Blink component*
>> Blink>WebGPU
>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EWebGPU%22>
>>
>> *Web Feature ID*
>> webgpu <https://webstatus.dev/features/webgpu>
>>
>> *Motivation*
>> In the current WGSL specification, the mere act of writing to
>> @builtin(frag_depth) often incurs a significant performance penalty because
>> driver heuristics cannot guarantee that the fragment shader output will
>> adhere to the depth written by the rasterizer's interpolated depth.
>> Consequently, writing to frag_depth typically forces the GPU to disable
>> crucial early-Z optimizations for the entire draw call. The introduction of
>> a new depth_mode built-in parameter for the @builtin(frag_depth) with modes
>> less, and greater directly addressing this performance limitation by
>> letting the developer express their intent to the hardware.
>>
>> *Initial public proposal*
>> https://github.com/gpuweb/gpuweb/blob/main/proposals/fragment-depth.md
>>
>> *TAG review*
>> *No information provided*
>>
>> *TAG review status*
>> Pending
>>
>> *Goals for experimentation*
>> None
>>
>> *Risks*
>>
>>
>> *Interoperability and Compatibility*
>> This feature has been approved in W3C GPU for the Web WG meetings
>> including participants from Safari and Firefox.
>>
>> *Gecko*: No signal (https://github.com/gpuweb/gpuweb/pull/6299) Feedback
>> indicated via WebGPU standardization process.
>>
>> *WebKit*: Positive (https://github.com/gpuweb/gpuweb/pull/6299) Specification
>> approval constitutes a positive signal, per
>> https://github.com/WebKit/standards-positions/issues/294#issuecomment-1877411933
>>
>> *Web developers*: No signals
>>
>> *Other signals*:
>>
>> *WebView application risks*
>>
>> Does this intent deprecate or change behavior of existing APIs, such that
>> it has potentially high risk for Android WebView-based applications?
>> *No information provided*
>>
>>
>> *Debuggability*
>> *No information provided*
>>
>> *Will this feature be supported on all six Blink platforms (Windows, Mac,
>> Linux, ChromeOS, Android, and Android WebView)?*
>> Yes
>> All platforms will eventually have support. Will immediately be available
>> on Android, Android WebView, ChromeOS, Mac, and Windows, where hardware
>> support is available. Linux is planned to have WebGPU support in the
>> future, so this feature will become available when WebGPU does.
>>
>> *Is this feature fully tested by web-platform-tests
>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>?*
>> Yes
>> WebGPU/WGSL have a conformance test suite (https://github.com/gpuweb/cts)
>> that is regularly pulled into Chromium and part of the testing of Dawn/Tint
>> in Chromium. While the CTS can be embedded in WPT, the WebGPU team opted to
>> keep it separate in Chromium testing to use a customized harness for
>> robustness and performance. * https://github.com/gpuweb/cts/pull/4679 *
>> https://github.com/gpuweb/cts/pull/4689
>>
>> *Flag name on about://flags*
>> *No information provided*
>>
>> *Finch feature name*
>> WebGPU
>>
>> *Rollout plan*
>> Will ship enabled for all users
>>
>> *Requires code in //chrome?*
>> False
>>
>> *Tracking bug*
>> https://crbug.com/457993779
>>
>> *Estimated milestones*
>>
>> No milestones specified
>>
>>
>> *Anticipated spec changes*
>>
>> Open questions about a feature may be a source of future web compat or
>> interop issues. Please list open issues (e.g. links to known github issues
>> in the project for the feature specification) whose resolution may
>> introduce web compat/interop risk (e.g., changing to naming or structure of
>> the API in a non-backward-compatible way).
>> *No information provided*
>>
>> *Link to entry on the Chrome Platform Status*
>> https://chromestatus.com/feature/5663304168112128?gate=5657119415205888
>>
>> This intent message was generated by Chrome Platform Status
>> <https://chromestatus.com>.
>>
>

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