SkPdf: smaller color serialization

SkPdf: smaller color serialization

SkPDFUtils now has a special function (SkPDFUtils::AppendColorComponent)
just for writing out (color/255) as a decimal with three digits of
precision.

SkPDFUnion now has a type to represent a color component.  It holds a
utint_8, but calls into AppendColorComponent to serialize.

Added a unit test that tests all possible input values.
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2151863003

Committed: https://skia.googlesource.com/skia/+/eb92cb3e84f49b5eedb22b36acffd895d6a90e5a

[hal.canary, 2016-07-14 16:42:38]

Description was changed from

==========
SkPdf: smaller color serialization

SkPDFUtils now has a special function (SkPDFUtils::AppendColorComponent)
just for writing out (color/255) as a decimal with three digits of
precision.

SkPDFUnion now has a type to represent a color component.  It holds a
utint_8, but calls into AppendColorComponent to serialize.

Added a unit test that tests all possible input values.
==========

to

==========
SkPdf: smaller color serialization

SkPDFUtils now has a special function (SkPDFUtils::AppendColorComponent)
just for writing out (color/255) as a decimal with three digits of
precision.

SkPDFUnion now has a type to represent a color component.  It holds a
utint_8, but calls into AppendColorComponent to serialize.

Added a unit test that tests all possible input values.
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2151863003
==========

[hal.canary, 2016-07-14 16:43:22]

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

[commit-bot: I haz the power, 2016-07-14 16:43:27]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-14 16:56:16]

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

[commit-bot: I haz the power, 2016-07-14 16:56:17]

Dry run: Try jobs failed on following builders:
  Build-Win-MSVC-x86_64-Debug-Trybot on master.client.skia.compile (JOB_FAILED,
http://build.chromium.org/p/client.skia.compile/builders/Build-Win-MSVC-x86_6...)

[hal.canary, 2016-07-14 17:44:23]

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

[commit-bot: I haz the power, 2016-07-14 17:44:31]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[hal.canary, 2016-07-14 17:53:10]

halcanary@google.com changed reviewers:
+ tomhudson@google.com

[hal.canary, 2016-07-14 17:53:10]

PTAL

[commit-bot: I haz the power, 2016-07-14 18:10:59]

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

[commit-bot: I haz the power, 2016-07-14 18:11:01]

Dry run: This issue passed the CQ dry run.

[tomhudson, 2016-07-15 19:20:18]

https://codereview.chromium.org/2151863003/diff/20001/src/pdf/SkPDFUtils.cpp
File src/pdf/SkPDFUtils.cpp (right):

https://codereview.chromium.org/2151863003/diff/20001/src/pdf/SkPDFUtils.cpp#...
src/pdf/SkPDFUtils.cpp:261: // ((int)(0.5 + (1000.0 / 255.0) * value) == x);
Not sure what the comment is doing here - it's mostly a literal restatement of
the line above?

After a fair amount of thought, I'm still not confident I know what you intend
by the <<20.

https://codereview.chromium.org/2151863003/diff/20001/src/pdf/SkPDFUtils.cpp#...
src/pdf/SkPDFUtils.cpp:268: for (j = 3; j > 1; --j) {
Trimming off trailing zeroes? Is this important?

[hal.canary, 2016-07-15 19:46:42]

https://codereview.chromium.org/2151863003/diff/20001/src/pdf/SkPDFUtils.cpp
File src/pdf/SkPDFUtils.cpp (right):

https://codereview.chromium.org/2151863003/diff/20001/src/pdf/SkPDFUtils.cpp#...
src/pdf/SkPDFUtils.cpp:261: // ((int)(0.5 + (1000.0 / 255.0) * value) == x);
On 2016/07/15 19:20:18, tomhudson wrote:
> Not sure what the comment is doing here - it's mostly a literal restatement of
> the line above?
> 
> After a fair amount of thought, I'm still not confident I know what you intend
> by the <<20.

To make this more clear, I am switching to SkFixed.

https://codereview.chromium.org/2151863003/diff/20001/src/pdf/SkPDFUtils.cpp#...
src/pdf/SkPDFUtils.cpp:268: for (j = 3; j > 1; --j) {
On 2016/07/15 19:20:17, tomhudson wrote:
> Trimming off trailing zeroes? Is this important?

it's cheap to do here, and everyone wants smaller PDFs.

[tomhudson, 2016-07-15 20:16:46]

lgtm

[hal.canary, 2016-07-15 20:18:46]

The CQ bit was checked by halcanary@google.com

[commit-bot: I haz the power, 2016-07-15 20:18:57]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-15 20:41:30]

Description was changed from

==========
SkPdf: smaller color serialization

SkPDFUtils now has a special function (SkPDFUtils::AppendColorComponent)
just for writing out (color/255) as a decimal with three digits of
precision.

SkPDFUnion now has a type to represent a color component.  It holds a
utint_8, but calls into AppendColorComponent to serialize.

Added a unit test that tests all possible input values.
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2151863003
==========

to

==========
SkPdf: smaller color serialization

SkPDFUtils now has a special function (SkPDFUtils::AppendColorComponent)
just for writing out (color/255) as a decimal with three digits of
precision.

SkPDFUnion now has a type to represent a color component.  It holds a
utint_8, but calls into AppendColorComponent to serialize.

Added a unit test that tests all possible input values.
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2151863003

Committed:
https://skia.googlesource.com/skia/+/eb92cb3e84f49b5eedb22b36acffd895d6a90e5a
==========

[commit-bot: I haz the power, 2016-07-15 20:41:31]

Committed patchset #3 (id:40001) as
https://skia.googlesource.com/skia/+/eb92cb3e84f49b5eedb22b36acffd895d6a90e5a