869703 - WebGL failure retrieving uniform

Status: RESOLVED FIXED

(Core :: Graphics: CanvasWebGL, defect)

Description

[Roberto Agostino Vitillo]

Attachment: testcase

The attached test generates the following error (v. 20.0.1):

Warning: Error: WebGL: UniformMatrix2fv: this function expected a uniform of element size 4, got a uniform of element size 0
Source File: file:///home/vitillo/sandbox/webgl/Tut04/test.html
Line: 33

The issue seems to be that an uniform info is retrieved only on demand by reading the information from the attached shaders. If the program has been successfully linked and the shaders detached then the search will fail. Nevertheless the operation should succeed even if the shaders have been detached after linking.

Comment 1

[Roberto Agostino Vitillo]

Attachment: Patch with a possible solution.

Comment 2

[Kelsey Gilbert [:jgilbert]]

Comment on attachment 746674 [details] [diff] [review]
Patch with a possible solution.

Review of attachment 746674 [details] [diff] [review]:
-----------------------------------------------------------------

Looks good, but we should add this assert.

::: content/canvas/src/WebGLProgram.cpp
@@ -224,4 @@
>  
>  WebGLUniformInfo
>  WebGLProgram::GetUniformInfoForMappedIdentifier(const nsACString& name) {
> -    if (!mUniformInfoMap) {

Assert that mUniformInfoMap is present.

Comment 3

[Benoit Jacob [:bjacob] (mostly away)]

Great analysis and patch! Thanks!

Comment 4

[(mostly gone) XtC4UaLL [:xtc4uall]]

Forgot to check this in?

Comment 5

[Benoit Jacob [:bjacob] (mostly away)]

Indeed, please make a version of the patch with a commit message

   Bug xxx - what the patch actually does - r=jgilbert

and flag the patch with 'checkin?'

Comment 6

[Roberto Agostino Vitillo]

Attachment: patch

Comment 7

[Ryan VanderMeulen [:RyanVM]]

This patch doesn't apply. Please make sure it was generated per the directions below.
https://developer.mozilla.org/en-US/docs/Mercurial_FAQ#How_can_I_generate_a_patch_for_somebody_else_to_check-in_for_me.3F

Comment 8

[Roberto Agostino Vitillo]

Attachment: patch

Comment 9

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/5443b4e12cda

Thanks for the patch, Roberto! :)

Comment 10

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/5443b4e12cda