[webkit-help] Finding "visible" region of element, or preventing overlap in layout

[Simon Fraser]

On Feb 18, 2012, at 10:34 AM, Konstantin Tokarev wrote:

> 16.02.2012, 18:21, "Konstantin Tokarev" <annulen at yandex.ru>:
>> Hi all,
>> 
>> I'm developing custom media engine (i.e. MediaPlayerPrivate subclass etc.) for embedded platform, and due to platform's limitations I have to render video on top of all page layers. This leads to broken rendering of elements which overlap video region.
>> 
>> I can imagine two ways to solve this problem:
>> 1) Get "visible" region of <video> element, i.e. region which is not overlapped by other elements, and crop video frame to it.
>> 2) Give some hint to layout manager to prevent all elements from overlapping <video>
>> 
>> Could anyone give me some hints on it?
> 
> Bump.
> 
> There is absolutely no possibility of using accelerated compositing for video element rendering because video has to be run in different hardware layer. "Dirty hacks" like inserting fake elements would be OK.

The whole point of accelerated compositing mode is to put elements in the page into their own hardware layers, and video is one of the things already handled this way.

What the accelerated compositing code does not do is to deal with limited numbers of hardware layers (e.g. if you just have 2 or 3 hardware planes). But I think you could deal with that under the GraphicsLayer code.

Simon