web applications - Is there a limit of vertices in WebGL?

Question

Three.js says that can't be loaded more than 65k vertices. In my pure webgl application, it doesn't say anything, but it doesn't show the entire object when I try big objects.

I am figuring out in split my objects to put in smaller buffers, but it would make me sad. Is there any better solution? Is 65k really the limit amount of vertices?

Answer 1

Yes, WebGL's vertex index buffers are limited to 16-bit right now. This is because they're aiming to make version 1.0 as cross-platform as possible, so there's a tendency to make stuff target the lowest common denominator -- in cases like this, mobile platforms with limited graphics hardware.

Once 1.0 is out and the initial rush is over, they're likely to loosen these constraints with the help of extensions -- an app will be able to ask whether a given extension is supported by the implementation, and make use of it if it is -- just like in regular desktop OpenGL. There are already a few extensions available, but again they've only allowed ones with very broad hardware support, so nothing that would help you increase your vertex count. However, once they loosen the cross-platform requirement, they are likely to support something like the GL_OES_element_index_uint extension that allows 32-bit vertex indices.

You can read some discussion of these issues on the Public WebGL mailing list.