Is there a reason why DataView wasn't specified as static methods that take an ArrayBuffer in the first place? That would solve the problem of figuring out when/how often to create DataView instances, and eliminate the garbage created by using DataViews.
On Tue, Apr 2, 2013 at 3:23 PM, Kenneth Russell <k...@google.com> wrote: > On Tue, Apr 2, 2013 at 3:03 PM, Aymeric Vitte <vitteayme...@gmail.com> > wrote: > > > > Le 02/04/2013 04:24, Kenneth Russell a écrit : > >> > >> Agreed. DataView's methods are all simple and should be easy to > >> optimize. Because they include a conditional byte swap, they can't run > >> quite as fast as the typed arrays' accessors -- but they shouldn't > >> need to. DataView was designed to support file and network I/O, where > >> throughput is limited by the disk or network connection. The typed > >> array views were designed for in-memory assembly of data to be > >> submitted to the graphics card, sound card, etc., and must run as fast > >> as possible. > > > > When you are streaming things, what's the correct use of DataViews? > > > > ie : you are supposed to create each time you want to read some bytes a > > DataView (which can be optimized or whatever, but still with some costs)? > > > > Maybe it's outside of the scope of this discussion, I have already > provided > > examples, I still suspect that I am using it wrongly or that ArrayBuffers > > are more adapted to webgl (ie static buffer manipulation) than network > > streaming (ie dynamic buffer manipulation). > > > > Probably I am wrong but really would like to know then what's the correct > > use. > > If I understand your question, then the correct use of DataView is: > upon receiving an ArrayBuffer, create a DataView referring to it. When > iterating down the contents of the ArrayBuffer, continue to use the > same DataView instance, just incrementing the offset. In > abstract-tls/lib/abstract-tls.js there are some operations which > create a new DataView just to read or write a single element; this > isn't the correct usage. > http://www.html5rocks.com/en/tutorials/webgl/typed_arrays/ may be a > useful reference. > > If you're handling streaming data then presumably you're receiving > multiple ArrayBuffers, one after the other. You should create one > DataView per buffer. The only challenge is properly handling the > boundary from one buffer to the next, if the boundary is within an > element like a uint16 or uint32. > > -Ken > -- -kg
_______________________________________________ es-discuss mailing list es-discuss@mozilla.org https://mail.mozilla.org/listinfo/es-discuss
