[webkit-dev] WebKit GPU rendering possibility

[zan at falconsigh.net]

On Fri, Nov 4, 2016, at 02:34 PM, Rogovin, Kevin wrote:
> Hi,
> 
> >I should mention, though, that we require support for hardware that only supports OpenGL ES 2.0. 
> >If FastUIDraw can't handle this, then we would need to keep a fallback codepath that uses Cairo, which would be unfortunate.
> 
> FastUIDraw requires features beyond what OpenGL ES 2.0 offers. With that
> in mind, the fall back is needed.
> 
> I cannot stress how unfortunate it is to have the burden of needing to
> support hardware that only satisfies a specification that is nearly 10
> years old and whose feature set corresponds to far more ancient times
> (essentially first generation DX9 cards, over 11 years ago). The jump in
> flexibility in handling data between ES2.0 and ES3.0/3.1 is massive.
> 

It is unfortunate, yet that is the reality for most of the Linux ports. 
WebKit can still run pretty darn nice on older hardware that only
supports ES 2.0 (of course depending on the content), and there's enough
interest to maintain that support.

I don't think supporting OpenGL ES 2.0 in FastUIDraw should be a
requirement, so we'll have to keep Cairo as a fallback and baseline
rasterizer.

> One question, what happens with WebGL 2.0 support on WebKit? I ask
> because WebGL 2.0 is essentially OpenGL ES 3.x for JavaScript.
> 

WebGL 2.0 wouldn't be supported on platforms that don't offer OpenGL ES
3.0. This should be manageable at runtime.

Regards,
Zan