Bug 169999 – texImage2D for a half-float texture only accepts null

• Status: RESOLVED
• Resolution: FIXED
• Component: WebGL

[Florian Bösch]

Calling texImage2D for a half-float texture only accepts null on iOS. The WebGL specification states that acceptable values are null,

- The specification states that texImage2D for half-float has to accept null, Uint16Array, <image>, <video> and <canvas>: https://www.khronos.org/registry/webgl/extensions/OES_texture_half_float/
- The conformance test for WebGL tests for the upload behavior fails on iOS: https://www.khronos.org/registry/webgl/sdk/tests/conformance/extensions/oes-texture-half-float.html

[Marcin Ignac]

Just run into the same issue as well. The conformance suite fails in

Version 10.1 (12603.1.30.0.34)
Release 27 (Safari 10.2, WebKit 12604.1.15.2)

[Radar WebKit Bug Importer]

<rdar://problem/31713571>

Tested on OSX/macOS 10.12, Safari Technology Preview (Release 47, Safari 11.1, WebKit 12605.1.19.1)

-go to https://files.unity3d.com/stefan/bugs/webkit_errors/index.html
--this is just a default empty scene from lates Unity (2017.3)
-open browser console
-see the following error being logged twice:
--WebGL: INVALID_OPERATION: texImage2D: type HALF_FLOAT_OES but ArrayBufferView is not NULL

-appears to have no visual effects on the scene
-error is not being thrown on latest Firefox or Chrome on same OSX

[jonobr1]

I'm running into the same issue as well. Found in this bug: https://bugs.webkit.org/show_bug.cgi?id=183321

Unity3D engine runs into this issue as well.

Safari 8 - Safari 12 are affected.

Tested as a workaround to use GL.texImage2D(..., null); to create an uninitialized texture, but then immediately afterwards using GL.texSubImage2D(..., /*type=*/0x8d61/*GL_HALF_FLOAT_OES*/, uint16Array); to upload the content, but unfortunately that fails too, i.e. GL.texSubImage2D() neither allows passing a half-float array.

Also tried a workaround to pass a Float32Array, or a Float64Array instead of a Uint16Array, wishfully thinking that perhaps the error message would be wrong, and half-float textures could be populated by submitting another array type instead, but that does not work either.

As result, Unity3D support of half-float textures is disabled, which prevents Safari from running new Unity3D content, which utilize half-floats.

[Dean Jackson]

Created attachment 381258 [details]
Patch

[Dean Jackson]

*** Bug 183321 has been marked as a duplicate of this bug. ***

[Dean Jackson]

Created attachment 381332 [details]
EWS run 2

[Dean Jackson]

Committed r251303: <https://trac.webkit.org/changeset/251303>