FWIW as developers of the browser game engine Construct (
https://www.construct.net/) we want this to be able to optimize 3D
rendering in WebGPU. We already use EXT_conservative_depth in the WebGL
renderer where available, and this brings the same feature to WebGPU.

Ashley


On Tue, 25 Aug 2026 at 04:14, 'dan sinclair' via blink-dev <
[email protected]> wrote:

> 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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