Several fixes for fp 16 rendering:

Several fixes for fp 16 rendering:

With the GPU backend, allow F16 render targets to be created (along with
any other renderable format). We were previously just falling back to 8888.

In SampleApp, if the window configuration is F16, don't render directly
to the primary surface (which is actually sRGB 8888). Intead, make an
off-screen F16 surface, then blit it back to the framebuffer when we're done.

In DM, clamp values outside of [0,1]. These were wrapping, producing very
incorrect images. (Many filters can trigger out-of-range values due to
ringing).

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1890923003

Committed: https://skia.googlesource.com/skia/+/6b08652abff788a251db82ca2b5f6b359ffe2590

[Brian Osman, 2016-04-14 18:19:24]

Description was changed from

==========
Several fixes for fp 16 rendering:

With the GPU backend, allow F16 render targets to be created (along with
any other renderable format). We were previously just falling back to 8888.

In SampleApp, if the window configuration is F16, don't render directly
to the primary surface (which is actually sRGB 8888). Intead, make an
off-screen F16 surface, then blit it back to the framebuffer when we're done.

In DM, clamp values outside of [0,1]. These were wrapping, producing very
incorrect images. (Many filters can trigger out-of-range values due to
ringing).

BUG=skia:
==========

to

==========
Several fixes for fp 16 rendering:

With the GPU backend, allow F16 render targets to be created (along with
any other renderable format). We were previously just falling back to 8888.

In SampleApp, if the window configuration is F16, don't render directly
to the primary surface (which is actually sRGB 8888). Intead, make an
off-screen F16 surface, then blit it back to the framebuffer when we're done.

In DM, clamp values outside of [0,1]. These were wrapping, producing very
incorrect images. (Many filters can trigger out-of-range values due to
ringing).

BUG=skia:
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
==========

[Brian Osman, 2016-04-14 18:25:40]

The CQ bit was checked by brianosman@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-04-14 18:25:50]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1890923003/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1890923003/20001

[Brian Osman, 2016-04-14 18:26:06]

brianosman@google.com changed reviewers:
+ bsalomon@google.com, mtklein@google.com, reed@google.com

[commit-bot: I haz the power, 2016-04-14 18:43:22]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-04-14 18:43:23]

Dry run: This issue passed the CQ dry run.

[mtklein, 2016-04-14 19:11:48]

lgtm

[mtklein, 2016-04-14 19:20:13]

https://codereview.chromium.org/1890923003/diff/20001/dm/DM.cpp
File dm/DM.cpp (left):

https://codereview.chromium.org/1890923003/diff/20001/dm/DM.cpp#oldcode962
dm/DM.cpp:962: Sk4f fs = SkHalfToFloat_01(px[i]);    // Convert up to linear
floats.
FYI folks, I do intend to replace SkHalfToFloat_01() with
SkHalfToFloat_finite(), which should let us get back to something short here.

https://codereview.chromium.org/1890923003/diff/20001/dm/DM.cpp
File dm/DM.cpp (right):

https://codereview.chromium.org/1890923003/diff/20001/dm/DM.cpp#newcode969
dm/DM.cpp:969: fs = Sk4f::Min(Sk4f::Max(fs, vecZero), vecOne);  // Clamp
I like to write this as

   fs = Sk4f::Max(0.0f, Sk4f::Min(fs, 1.0f));

It puts the value visually between its min and max.

(You can use scalars and literals with Sk4f.  I think even Sk4f::Max(0,
Sk4f::Min(fs, 1)) is fine here.)

[Brian Osman, 2016-04-14 19:25:00]

The CQ bit was checked by brianosman@google.com

[Brian Osman, 2016-04-14 19:25:01]

The patchset sent to the CQ was uploaded after l-g-t-m from mtklein@google.com
Link to the patchset: https://codereview.chromium.org/1890923003/#ps40001
(title: "Nicer looking clamp")

[commit-bot: I haz the power, 2016-04-14 19:25:12]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1890923003/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1890923003/40001

[commit-bot: I haz the power, 2016-04-14 19:39:02]

Description was changed from

==========
Several fixes for fp 16 rendering:

With the GPU backend, allow F16 render targets to be created (along with
any other renderable format). We were previously just falling back to 8888.

In SampleApp, if the window configuration is F16, don't render directly
to the primary surface (which is actually sRGB 8888). Intead, make an
off-screen F16 surface, then blit it back to the framebuffer when we're done.

In DM, clamp values outside of [0,1]. These were wrapping, producing very
incorrect images. (Many filters can trigger out-of-range values due to
ringing).

BUG=skia:
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
==========

to

==========
Several fixes for fp 16 rendering:

With the GPU backend, allow F16 render targets to be created (along with
any other renderable format). We were previously just falling back to 8888.

In SampleApp, if the window configuration is F16, don't render directly
to the primary surface (which is actually sRGB 8888). Intead, make an
off-screen F16 surface, then blit it back to the framebuffer when we're done.

In DM, clamp values outside of [0,1]. These were wrapping, producing very
incorrect images. (Many filters can trigger out-of-range values due to
ringing).

BUG=skia:
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...

Committed:
https://skia.googlesource.com/skia/+/6b08652abff788a251db82ca2b5f6b359ffe2590
==========

[commit-bot: I haz the power, 2016-04-14 19:39:03]

Committed patchset #3 (id:40001) as
https://skia.googlesource.com/skia/+/6b08652abff788a251db82ca2b5f6b359ffe2590