[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: [Public WebGL] readPixles() can't access float values (OES_texture_float interaction)
- To: Benoit Jacob <[email protected]>
- Subject: RE: [Public WebGL] readPixles() can't access float values (OES_texture_float interaction)
- From: "Ribble, Maurice" <[email protected]>
- Date: Tue, 30 Aug 2011 18:23:50 +0000
- Accept-language: en-US
- Cc: Christian Junker <[email protected]>, "[email protected]" <[email protected]>
- Dkim-signature: v=1; a=rsa-sha256; c=simple/simple; d=qualcomm.com; [email protected]; q=dns/txt; s=qcdkim; t=1314728760; x=1346264760; h=from:to:cc:subject:thread-topic:thread-index:date: message-id:references:in-reply-to:accept-language: content-language:x-ms-has-attach:x-ms-tnef-correlator: x-originating-ip:content-type:content-transfer-encoding: mime-version; z=From:=20"Ribble,=20Maurice"=20<[email protected]>|To: =20Benoit=20Jacob=20<[email protected]>|CC:=20Christian =20Junker=20<[email protected]>,=0D=0A=09"publ [email protected]"=20<[email protected]> |Subject:=20RE:=20[Public=20WebGL]=20readPixles()=20can't =20access=20float=20values=0D=0A=20(OES_texture_float=20i nteraction)|Thread-Topic:=20[Public=20WebGL]=20readPixles ()=20can't=20access=20float=20values=0D=0A=20(OES_texture _float=20interaction)|Thread-Index:=20AQHMY+Kzh8IuGxrwDES MLjliYx8dtJU2IWyA//+QVUCAAHcogP//kWrw|Date:=20Tue,=2030 =20Aug=202011=2018:23:50=20+0000|Message-ID:=20<6EDD22A17 [email protected] om>|References:=20<CANPDqYdExg064USgGarNG18mdapohzB4qXDty [email protected]>=0D=0A=20<[email protected] ozilla.com>=0D=0A=20<6EDD22A170C08F44982E1F9895B3537D049B [email protected]>=0D=0A=20<4E5D2381.80007 [email protected]>|In-Reply-To:=20<[email protected] com>|Accept-Language:=20en-US|Content-Language:=20en-US |X-MS-Has-Attach:|X-MS-TNEF-Correlator:|x-originating-ip: =20[199.106.114.10]|Content-Type:=20text/plain=3B=20chars et=3D"iso-8859-1"|Content-Transfer-Encoding:=20quoted-pri ntable|MIME-Version:=201.0; bh=Na7xI+m6UlbwlhXJGcfU65Ox9FZShTA2ufM2vQZJ3jU=; b=cq2MakG3lHAy8XMaHtF3tYR8Y/x3HV/Ggew+7QrMWBH/CpPaVl0LSSi2 6iV/ip6Ivdew3LO7VnIS9ToMcu0t2R2xue2v/S0+eHzJsWpWnsfQWJbhP VVTVnhE591JAOGDFUQW78/Df18vmPTWkHVTaLJLRaakaYodpgkk5UOoFX U=;
- In-reply-to: <[email protected]>
- List-id: Public WebGL Mailing List <public_webgl.khronos.org>
- References: <[email protected]om> <[email protected]> <[email protected].com> <[email protected]>
- Sender: [email protected]
- Thread-index: AQHMY+Kzh8IuGxrwDESMLjliYx8dtJU2IWyA//+QVUCAAHcogP//kWrw
- Thread-topic: [Public WebGL] readPixles() can't access float values (OES_texture_float interaction)
In our current drivers we support GL_OES_texture_float, GL_OES_texture_half_float, and GL_OES_texture_half_float_linear. In order to render to an FP buffer there is a lot of spec language that needs to be added and these extensions don't have anything about that so I don't think it is legal to bind these formats to an FBO. You would need to have additional extensions defining clamp and a bunch of other things.
-Maurice
-----Original Message-----
From: Benoit Jacob [mailto:[email protected]]
Sent: Tuesday, August 30, 2011 1:53 PM
To: Ribble, Maurice
Cc: Christian Junker; [email protected]
Subject: Re: [Public WebGL] readPixles() can't access float values (OES_texture_float interaction)
What do you mean? I was not aware of the distinction between "texturing"
and "rendering" formats. Isn't it allowed to use a float texture as the
color attachment of a framebuffer? Why disable readPixels on such
framebuffers then?
Regardless, are you saying that this is unsupported on Qualcomm
chips/drivers?
Cheers,
Benoit
On 30/08/11 01:48 PM, Ribble, Maurice wrote:
> They are only texturing and not for rendering, therefore readpixels does not make sense.
>
> -Maurice
>
> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On Behalf Of Benoit Jacob
> Sent: Tuesday, August 30, 2011 1:26 PM
> To: Christian Junker
> Cc: [email protected]
> Subject: Re: [Public WebGL] readPixles() can't access float values (OES_texture_float interaction)
>
>
> As far as I can see, this question boils down to whether or not all
> OpenGL[ES] implementations which support float textures also support
> readPixels on them.
>
> If they do support that, then I don't see why we shouldn't support that too.
>
> If some of them don't support that, then there's no way that we'll be
> able to support that on top of them.
>
> Does anyone know how widely this is supported?
>
> Cheers,
> Benoit
>
>
>
> On 26/08/11 07:20 AM, Christian Junker wrote:
>>
>> Hi,
>>
>> Although floating point textures are supported through the
>> "OES_texture_float" extension, it is currently not possible to read
>> back the pixels from the framebuffer.
>> Using readPixels() does only work für UNSIGNED_BYTE (as described in the spec).
>> The specification of the extension
>> (http://www.khronos.org/registry/gles/extensions/OES/OES_texture_float.txt)
>> doesn't mention interaction with readPixels() at all.
>>
>> My question now is, is this an oversight or desired behavior? (or did
>> I simply overlook something?)
>>
>> I think allowing readPixels() to play together with floating point
>> textures would be a highly desireable feature, esp. for
>> diagnosing/debugging and gpgpu.
>>
>>
>> Short example:
>>
>> var pixels = new Float32Array(framebuffer.width * framebuffer.height * 4);
>> gl.readPixels(0, 0, framebuffer.width, framebuffer.height, gl.RGBA,
>> gl.FLOAT, pixels);
>>
>> results in "Warning: WebGL: ReadPixels: type: invalid enum value 0x1406"
>>
>>
>> Rest Regards
>> Christian
>>
>> -----------------------------------------------------------
>> You are currently subscribed to [email protected]
>> To unsubscribe, send an email to [email protected] with
>> the following command in the body of your email:
>> unsubscribe public_webgl
>> -----------------------------------------------------------
>>
>
>
> -----------------------------------------------------------
> You are currently subscribed to [email protected]
> To unsubscribe, send an email to [email protected] with
> the following command in the body of your email:
> unsubscribe public_webgl
> -----------------------------------------------------------
>
-----------------------------------------------------------
You are currently subscribed to [email protected]
To unsubscribe, send an email to [email protected] with
the following command in the body of your email:
unsubscribe public_webgl
-----------------------------------------------------------