If you mean this sentence from the docs:

"This allows you to use glDrawArrays 
<https://www.opengl.org/sdk/docs/man3/xhtml/glDrawArrays.xml> etc. without 
a bound buffer,..."

This simply means that you can render directly from a 'client-side' memory 
chunk with vertex-data instead of having the vertex data stored in a GL 
buffer, in this case glVertexAttribPointer is called with an actual pointer 
to the data, instead of an offset into a buffer). It may simplify porting 
some desktop-GL code, but is not recommended, since the GL shim needs to 
create and update a GL buffer under the hood.

The other possible meaning of rendering without a buffer would be 
'attribute-less-rendering', where you don't provide any input geometry to 
the vertex shader, but instead use the generated vertex-id and/or 
instance-id to lookup vertex positions in an uniform array. Not sure if 
this is possible in WebGL though (see here: 
http://renderingpipeline.com/2012/03/attribute-less-rendering/)

Cheers,
-Floh.

Am Freitag, 18. September 2015 05:52:17 UTC+2 schrieb [email protected]:
>
> What is the ETA on OpenGL ES 3.0 support for Emscripten?
>
> ( http://bit.ly/1Qjunsp ) says Emscripten supports OpenGL ES 2.0. 
>  However, I see no mention of OpenGL ES 3.0?
>
> As for OpenGL ES 2.0 support, apparently this means the WebGL-friendly 
> subset of OpenGL + the ability to use glDrawArrays() without a bound 
> buffer.  Does "without a bound buffer" mean without calling glBindBuffer()?
>
> Why would you want to call glDrawArrays() without first calling 
> glBindBuffer()?  Wouldn't that mean to draw nothing?
>
>

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