- From: Rik Cabanier <cabanier@gmail.com>
- Date: Sun, 23 Mar 2014 12:20:52 -0700
- To: Dirk Schulze <dschulze@adobe.com>
- Cc: WHATWG List <whatwg@whatwg.org>
On Sat, Mar 22, 2014 at 11:31 PM, Dirk Schulze <dschulze@adobe.com> wrote: > Hi, > > I was reading the spec part about ImageData [1]. > > 1) > I noticed that createImageData() is explicit that it represent a > transparent black rectangle. The constructor for ImageData is not that > explicit. > Yes, that seems like an oversight. > 2) > The last step of the 2nd constructor that takes an Uint8ClampedArray says: > " * Return a new ImageData object whose width is sw, whose height is > height, and whose data is source." > > Is data a reference to the original source or a copy of source? It is the original source. The spec does not say anything about creating a new array and copying the bits over. > For the former, there might be two ImageData objects referencing the same > ByteArray. How would that be useful? > You *could* use the API that way but I don't see why there has to be a way to prevent that from happening. Is there an implementation issue if 2 different imageData object point to the same dataarray/ > [1] > http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#dfnReturnLink-7(4.12.4.2.16 Pixel manipulation) Correct link is: http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#pixel-manipulation
Received on Sunday, 23 March 2014 19:34:20 UTC