[webkit-qt] [webkit-dev] How to enable WebGL on WebKit QT port?

[Joseph Tsai]

Hello Jarkko,

I think this issue is just a design choice. In Chromium's port, if
certain GL functions are not supported natively, it uses the software
emulated part to fill out the unsupported part.

I can understand that mixing native GL functions and emulated ones is
more complex, and developers may decide that it is not worse to spend
lots of time to implement such a mixing infrastructure in the current
stage. But it cannot be claimed that supporting partial set of GL
function is not achievable. We just can say that the mixing mechanism
would not supported currently since we don't want to incorporate more
architectural complexity.


Sincerely,
Joseph


2011/5/11 Jarkko Sakkinen <jarkko.sakkinen at iki.fi>:
> Hi Joseph,
>
> On Thu, May 5, 2011 at 8:35 AM, Joseph Tsai <mgtsai at gmail.com> wrote:
>> Digging in sources, I found that QtWebKit's port would query available
>> OpenGL functions by GraphicsContext3DInternal::getProcAddress() from
>> DLL (in WebCore/platform/graphics/qt/GraphicsContext3DQt.cpp). Current
>> implementation is that: If certain OpenGL function is not available,
>> the WebGL feature is disabled (in the constructor of class
>> GraphicsContext3DInternal). For example, glBlendEquation() is not
>> supported in my Windows XP platform, although I don't need this
>> function, WebGL is still disabled in QtWebKit.
>
> You probably mean glBlendEquationSeparate() (possibly with EXT or ARB)
> right? glBlendEquation() is supported by practically all OpenGL implementations.
>
>> WebGL for QtWebKit does not support partial set of OpenGL functions,
>> this implementation is different from Chromium's port.
>> (Chromium can run WebGL under my Windows XP)
>
> This is bit problematic. WebGL 1.0 standard requires certain set of functions
> to be available. So allowing to initialize would not be compatible with the
> standard.
>
> BR, Jarkko
>