For reference, here is a prototype patch which implements :
https://bugs.webkit.org/show_bug.cgi?id=112624
And one which implements getContext('2d', { alpha: none }):
https://bugs.webkit.org/show_bug.cgi?id=112628
I believe this represents the bulk of the cross-port work that would be
required; th
On Thu, Mar 14, 2013 at 5:23 PM, Dean Jackson wrote:
>
> On 15/03/2013, at 8:06 AM, Gregg Tavares wrote:
>
> > Because it's not the same as fillRect(0, 0, width, height) on an empty
> canvas. The canvas itself has alpha (unless we add the option to not have
> it as has been proposed). The conten
On Thu, Mar 14, 2013 at 4:38 PM, Ryosuke Niwa wrote:
> On Thu, Mar 14, 2013 at 12:55 PM, Dean Jackson wrote:
>
>>
>> On 15/03/2013, at 6:50 AM, Dana Jansens wrote:
>>
>> On Thu, Mar 14, 2013 at 3:46 PM, Dean Jackson wrote:
>>
>>> I'm not sure I like this proposal. Why is canvas special? Why do
On 3/15/2013 6:23 PM, Kenneth Russell wrote:
Is there a nontrivial amount of content depending on it? That
would be more relevant precedent than merely being in the code base.
How would one determine that? Searching for "getcontext webgl alpha
false" returns many web pages on the topi
On Fri, Mar 15, 2013 at 1:35 AM, Maciej Stachowiak wrote:
>
> On Mar 15, 2013, at 1:19 AM, Gregg Tavares wrote:
>
>
> I don't understand the opposition to "alpha"
>
> You set colors in Canvas2d with rgb or rgba. That 'a' in rgba stands for
> alpha.
> You can set a global alpha for drawing with c
On Mar 15, 2013, at 1:19 AM, Gregg Tavares wrote:
>
> I don't understand the opposition to "alpha"
>
> You set colors in Canvas2d with rgb or rgba. That 'a' in rgba stands for
> alpha.
> You can set a global alpha for drawing with context.globalAlpha
> You read data from getImageData that ret
On Fri, Mar 15, 2013 at 9:19 AM, Gregg Tavares wrote:
> I don't understand the opposition to "alpha"
>
> You set colors in Canvas2d with rgb or rgba. That 'a' in rgba stands for
> alpha.
> You can set a global alpha for drawing with context.globalAlpha
> You read data from getImageData that retur
On Thu, Mar 14, 2013 at 7:47 PM, Ryosuke Niwa wrote:
> On Thu, Mar 14, 2013 at 7:45 PM, Dean Jackson wrote:
>
>> On 15/03/2013, at 12:49 PM, Vladimir Vukicevic
>> wrote:
>> > On 3/14/2013 5:23 PM, Dean Jackson wrote:
>> >> On 15/03/2013, at 8:06 AM, Gregg Tavares wrote:
>> >>> Because it's not
On Thu, Mar 14, 2013 at 7:45 PM, Dean Jackson wrote:
> On 15/03/2013, at 12:49 PM, Vladimir Vukicevic
> wrote:
> > On 3/14/2013 5:23 PM, Dean Jackson wrote:
> >> On 15/03/2013, at 8:06 AM, Gregg Tavares wrote:
> >>> Because it's not the same as fillRect(0, 0, width, height) on an empty
> canvas
On 15/03/2013, at 12:49 PM, Vladimir Vukicevic wrote:
> On 3/14/2013 5:23 PM, Dean Jackson wrote:
>> On 15/03/2013, at 8:06 AM, Gregg Tavares wrote:
>>> Because it's not the same as fillRect(0, 0, width, height) on an empty
>>> canvas. The canvas itself has alpha (unless we add the option to n
On 3/14/2013 5:23 PM, Dean Jackson wrote:
On 15/03/2013, at 8:06 AM, Gregg Tavares wrote:
Because it's not the same as fillRect(0, 0, width, height) on an empty canvas.
The canvas itself has alpha (unless we add the option to not have it as has
been proposed). The contents of the canvas has t
On 15/03/2013, at 8:06 AM, Gregg Tavares wrote:
> Because it's not the same as fillRect(0, 0, width, height) on an empty
> canvas. The canvas itself has alpha (unless we add the option to not have it
> as has been proposed). The contents of the canvas has to stay as the user
> created it. If
On Thu, Mar 14, 2013 at 2:00 PM, Dean Jackson wrote:
>
> On 15/03/2013, at 7:55 AM, Gregg Tavares wrote:
>
>
>
>
> On Thu, Mar 14, 2013 at 1:38 PM, Ryosuke Niwa wrote:
>
>> On Thu, Mar 14, 2013 at 12:55 PM, Dean Jackson wrote:
>>
>>>
>>> On 15/03/2013, at 6:50 AM, Dana Jansens wrote:
>>>
>>>
On 15/03/2013, at 7:55 AM, Gregg Tavares wrote:
>
>
>
> On Thu, Mar 14, 2013 at 1:38 PM, Ryosuke Niwa wrote:
> On Thu, Mar 14, 2013 at 12:55 PM, Dean Jackson wrote:
>
> On 15/03/2013, at 6:50 AM, Dana Jansens wrote:
>
>> On Thu, Mar 14, 2013 at 3:46 PM, Dean Jackson wrote:
>> I'm not su
On Thu, Mar 14, 2013 at 1:55 PM, Dean Jackson wrote:
>
> On 15/03/2013, at 7:45 AM, Kenneth Russell wrote:
>
>> On Thu, Mar 14, 2013 at 1:38 PM, Ryosuke Niwa wrote:
>>> On Thu, Mar 14, 2013 at 12:55 PM, Dean Jackson wrote:
On 15/03/2013, at 6:50 AM, Dana Jansens wrote:
On Thu, Mar 14, 2013 at 1:38 PM, Ryosuke Niwa wrote:
> On Thu, Mar 14, 2013 at 12:55 PM, Dean Jackson wrote:
>
>>
>> On 15/03/2013, at 6:50 AM, Dana Jansens wrote:
>>
>> On Thu, Mar 14, 2013 at 3:46 PM, Dean Jackson wrote:
>>
>>> I'm not sure I like this proposal. Why is canvas special? Why do
On 15/03/2013, at 7:45 AM, Kenneth Russell wrote:
> On Thu, Mar 14, 2013 at 1:38 PM, Ryosuke Niwa wrote:
>> On Thu, Mar 14, 2013 at 12:55 PM, Dean Jackson wrote:
>>>
>>>
>>> On 15/03/2013, at 6:50 AM, Dana Jansens wrote:
>>>
>>> On Thu, Mar 14, 2013 at 3:46 PM, Dean Jackson wrote:
>
On Thu, Mar 14, 2013 at 1:38 PM, Ryosuke Niwa wrote:
> On Thu, Mar 14, 2013 at 12:55 PM, Dean Jackson wrote:
>>
>>
>> On 15/03/2013, at 6:50 AM, Dana Jansens wrote:
>>
>> On Thu, Mar 14, 2013 at 3:46 PM, Dean Jackson wrote:
>>>
>>> I'm not sure I like this proposal. Why is canvas special? Why d
On Thu, Mar 14, 2013 at 12:55 PM, Dean Jackson wrote:
>
> On 15/03/2013, at 6:50 AM, Dana Jansens wrote:
>
> On Thu, Mar 14, 2013 at 3:46 PM, Dean Jackson wrote:
>
>> I'm not sure I like this proposal. Why is canvas special? Why doesn't
>> get an opaque attribute (or flag)? Why not every eleme
On Thu, Mar 14, 2013 at 12:46 PM, Dean Jackson wrote:
> I'm not sure I like this proposal. Why is canvas special? Why doesn't
> get an opaque attribute (or flag)? Why not every element?
>
> I don't think the performance benefit, which is mostly going to be on very
> limited hardware, is worth ch
On 15/03/2013, at 6:50 AM, Dana Jansens wrote:
> On Thu, Mar 14, 2013 at 3:46 PM, Dean Jackson wrote:
> I'm not sure I like this proposal. Why is canvas special? Why doesn't
> get an opaque attribute (or flag)? Why not every element?
>
> There is ongoing work to infer opaqueness in every oth
On Thu, Mar 14, 2013 at 3:46 PM, Dean Jackson wrote:
> I'm not sure I like this proposal. Why is canvas special? Why doesn't
> get an opaque attribute (or flag)? Why not every element?
>
There is ongoing work to infer opaqueness in every other kind of element
when possible. See for example http
I'm not sure I like this proposal. Why is canvas special? Why doesn't get
an opaque attribute (or flag)? Why not every element?
I don't think the performance benefit, which is mostly going to be on very
limited hardware, is worth changing the rendering model that is consistent
across every oth
Hi Dirk,
There have been at least five options considered, with contributions from
Chromium, Adobe and Mozilla so far. The moz-opaque idea was first floated
by Robert O'Callahan from Mozilla, and Ian Hickson offered to spec it if
another browser vendor wanted to implement it. I took him up on th
On Wed, Mar 13, 2013 at 9:49 PM, Gregg Tavares wrote:
> On Wed, Mar 13, 2013 at 9:20 PM, Maciej Stachowiak wrote:
>
>>
>> Two questions/comments:
>>
>> 1) What happens if I do:
>> gl = canvas.getContext("experimental-webgl", { alpha: false });
>> and then later, in an unrelated piece of code
On Mar 13, 2013, at 9:49 PM, Gregg Tavares wrote:
>
>
>
> On Wed, Mar 13, 2013 at 9:20 PM, Maciej Stachowiak wrote:
>
> Two questions/comments:
>
> 1) What happens if I do:
> gl = canvas.getContext("experimental-webgl", { alpha: false });
> and then later, in an unrelated piece of code
unify usage with WebGL and to make it easy to extend (e.g.,
>> preserveDrawingBuffer mentioned above). Firefox may well even stop
>> supporting moz-opaque; we never really publicized it anywhere and just used
>> it internally in the Firefox UI.
>>
>>- Vlad
>>
> preserveDrawingBuffer mentioned above). Firefox may well even stop
> supporting moz-opaque; we never really publicized it anywhere and just used
> it internally in the Firefox UI.
>
>- Vlad
>
> - Original Message -
>
> From: "Elliott Sprehn"
> To: "
n the Firefox UI.
>
>- Vlad
>
> - Original Message -
>> From: "Elliott Sprehn"
>> To: "Rik Cabanier"
>> Cc: "WebKit Development"
>> Sent: Wednesday, March 13, 2013 6:25:53 PM
>> Subject: Re: [webkit-dev] New we
he Firefox UI.
- Vlad
- Original Message -
> From: "Elliott Sprehn"
> To: "Rik Cabanier"
> Cc: "WebKit Development"
> Sent: Wednesday, March 13, 2013 6:25:53 PM
> Subject: Re: [webkit-dev] New web-facing canvas feature: "opaque" attrib
On Wed, Mar 13, 2013 at 1:02 PM, Maciej Stachowiak wrote:
>
> An attribute on the canvas element would presumably be equally applicable
> to all contexts. Is there a reason that it's better to have opaqueness
> specified at context creation time instead of on the canvas?
>
Changing opaque requir
globalAlpha will still work but will always composite with an opaque
backdrop (which is black by default)
On Wed, Mar 13, 2013 at 3:25 PM, Elliott Sprehn wrote:
> alpha:false is super confusing to me. It makes it sound as though all
> draw*() operations that use an alpha channel will fail... doe
alpha:false is super confusing to me. It makes it sound as though all
draw*() operations that use an alpha channel will fail... does globalAlpha
still work?
It's sad that WebGL picked such a generic name that isn't about all "alpha"
related things.
On Wed, Mar 13, 2013 at 2:59 PM, Rik Cabanier
The main reason for this feature is to enhance performance of canvas
operations.
Are we certain that this will always be the case? For instance, is google
going to make certain that the cairo and core graphics backends don't slow
down?
Rik
On Wed, Mar 13, 2013 at 1:21 PM, Brandon Jones wrote:
>
I think "opaque" vs. "alpha: false" is a matter of opinion. The
functionality doesn't change, regardless of what you call it.
I agree with Gregg that this really should be implemented to reflect the
functionality that WebGL already has. Wether 2D or 3D, there's a lot of
common ground between the v
An attribute on the canvas element would presumably be equally applicable to
all contexts. Is there a reason that it's better to have opaqueness specified
at context creation time instead of on the canvas? Also, I think "opaque" is
easier to understand than "alpha: false".
- Maciej
On Mar 13
It would be nice if this was the same as WebGL instead of different.
Especially because 2d canvas and WebGL need to inter-operate in the near
future.
In WebGL to create a canvas with no alpha (an opaque canvas) you do this
gl = canvas.getContext("experimental-webgl", { alpha: false });
Why ca
This is a very long thread and I did not see any conclusions or agreement on
this thread. Can you summarize the topic and the status on the acceptance level
please?
Greetings,
Dirk
On Mar 13, 2013, at 9:15 AM, Stephen White wrote:
> Hi WebKittens,
>
> I'm planning to implement the canvas "op
Hi WebKittens,
I'm planning to implement the canvas "opaque" attribute, as proposed here:
http://lists.w3.org/Archives/Public/public-whatwg-archive/2013Mar/0109.html.
This is an attribute that causes the allocation of an opaque backing store
for , allowing optimizations at the time the canvas is
39 matches
Mail list logo
