SkLiteRecorder, a new SkCanvas, fills out SkLiteDL, a new SkDrawable.
This SkDrawable is a display list similar to SkRecord and SkBigPicture / SkRecordedDrawable, but with a few new design points inspired by Android and slimming paint:
1) SkLiteDL is structured as one big contiguous array rather than the two layer structure of SkRecord. This trades away flexibility and large-op-count performance for better data locality for small to medium size pictures.
2) We keep a global freelist of SkLiteDLs, both reusing the SkLiteDL struct itself and its contiguous byte array. This keeps the expected number of mallocs per display list allocation <1 (really, ~0) for cyclical use cases.
These two together mean recording is faster. Measuring against the code we use at head, SkLiteRecorder trends about ~3x faster across various size pictures, matching speed at 0 draws and beating the special-case 1-draw pictures we have today. (I.e. we won't need those special case implementations anymore, because they're slower than this new generic code.) This new strategy records 10 drawRects() in about the same time the old strategy took for 2.
This strategy stays the winner until at least 500 drawRect()s on my laptop, where I stopped checking.
A simpler alternative to freelisting is also possible (but not implemented here), where we allow the client to manually reset() an SkLiteDL for reuse when its refcnt is 1. That's essentially what we're doing with the freelist, except tracking what's available for reuse globally instead of making the client do it.
This code is not fully capable yet, but most of the key design points are there. The internal structure of SkLiteDL is the area I expect to be most volatile (anything involving Op), but its interface and the whole of SkLiteRecorder ought to be just about done.
You can run nanobench --match picture_overhead as a demo. Everything it exercises is fully fleshed out, so what it tests is an apples-to-apples comparison as far as recording costs go. I have not yet compared playback performance.
It should be simple to wrap this into an SkPicture subclass if we want.
I won't start proposing we replace anything old with anything new quite yet until I have more ducks in a row, but this does look pretty promising (similar to the SkRecord over old SkPicture change a couple years ago) and I'd like to land, experiment, iterate, especially with an eye toward Android.
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2213333002
Review-Url: https://codereview.chromium.org/2213333002
This builds, links, and runs on Linux. Have not tried Mac.
I've tested is_debug={true,false} and is_component_build.
It's neat that the component build DM works, but it's also an indication I've missed an essential flag or two... it shouldn't work. :)
The GPU backend isn't working yet, but all the software configurations I've tried look good.
This fleshes out all the other parts of SkCodec too... I noticed we weren't able to decode gifs or webp.
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2188643002
Review-Url: https://codereview.chromium.org/2188643002
201295.jpg on HP z620
(300x280, most common form of sRGB profile)
QCMS Xform 0.495 ms
Skia Old Xform 0.235 ms
Skia NEW Xform 0.423 ms
Vs Old Code 0.56x
Vs QCMS 1.17x
So to summarize, we are now much slower than before,
but still a bit faster than QCMS. And now we are also
far more accurate than QCMS :).
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2060823003
CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
Review-Url: https://codereview.chromium.org/2060823003
Instead of two synchronization systems (in_signal_handler, gMutex),
we can just use one. This simplifies the signal handler logic to:
- first thread through grabs the lock, prints what's running and a stack trace,
then exits
- all other threads just sit waiting on that lock until exit kills them
Previously I think all threads were racing to exit, which can kill the process
before the printing thread is done. That truncated the output, which is dumb.
Plus...
refactor slightly so that crash_handler() shows up at the top of the stack
trace rather than some odd name for a lambda inside setup_crash_handler().
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2051863002
Review-Url: https://codereview.chromium.org/2051863002
$ git grep -l '<windows.h>' include src
include/private/SkLeanWindows.h
$ git grep -l SkLeanWindows.h | grep '\.h$'
include/ports/SkTypeface_win.h
include/utils/win/SkHRESULT.h
include/utils/win/SkTScopedComPtr.h
include/views/SkEvent.h
src/core/SkMathPriv.h
src/ports/SkTypeface_win_dw.h
src/utils/SkThreadUtils_win.h
src/utils/win/SkWGL.h
The same for `#include <intrin.h>` that was found in SkMath.h.
Those functions that needed it are moved to SkMathPriv.h.
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2041943002
CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_chromium_compile_dbg_ng,win_chromium_compile_rel_ng
Review-Url: https://codereview.chromium.org/2041943002
Reason for revert:
Still causing problems in Google3, e.g.
https://test.corp.google.com/ui#cl=124138817&flags=CAMQBQ==&id=OCL:124138817:BASE:124139560:1465227435491:219ffbdb&t=//third_party/skia/HEAD:dm
Original issue's description:
> Make SkPngCodec decode progressively.
>
> This is a step towards using SkCodec in Chromium, where progressive
> decoding is necessary.
>
> Switch from using png_read_row (which expects all the data to be
> available) to png_process_data, which uses callbacks when rows are
> available.
>
> Create a new API for SkCodec, which supports progressive decoding and
> scanline decoding. Future changes will switch the other clients off of
> startScanlineDecode and get/skip-Scanlines to the new API.
>
> Remove SkCodec::kNone_ScanlineOrder, which was only used for interlaced
> PNG images. In the new API, interlaced PNG fits kTopDown. Also remove
> updateCurrScanline(), which was only used by the old implementation for
> interlaced PNG.
>
> DMSrcSink:
> - In CodecSrc::kScanline_Mode, use the new method for scanline decoding
> for the supported formats (just PNG and PNG-in-ICO for now).
>
> fuzz.cpp:
> - Remove reference to kNone_ScanlineOrder
>
> SkCodec:
> - Add new APIs:
> - startIncrementalDecode
> - incrementalDecode
> - Remove kNone_SkScanlineOrder and updateCurrScanline()
>
> SkPngCodec:
> - Implement new APIs
> - Switch from sk_read_fn/png_read_row etc to png_process_data
> - Expand AutoCleanPng's role to decode the header and create the
> SkPngCodec
> - Make the interlaced PNG decoder report how many lines were
> initialized during an incomplete decode
> - Make initializeSwizzler return a bool instead of an SkCodec::Result
> (It only returned kSuccess or kInvalidInput anyway)
>
> SkIcoCodec:
> - Implement the new APIs; supported for PNG in ICO
>
> SkSampledCodec:
> - Call the new method for decoding scanlines, and fall back to the old
> method if the new version is unimplemented
> - Remove references to kNone_SkScanlineOrder
>
> tests/CodecPartial:
> - Add a test which decodes part of an image, then finishes the decode,
> and compares it to the straightforward method
>
> tests/CodecTest:
> - Add a test which decodes all scanlines using the new method
> - Repurpose the Codec_stripes test to decode using the new method in
> sections rather than all at once
> - In the method check(), add a parameter for whether the image supports
> the new method of scanline decoding, and be explicit about whether an
> image supports incomplete
> - Test incomplete PNG decodes. We should have been doing it anyway for
> non-interlaced (except for an image that is too small - one row), but
> the new method supports interlaced incomplete as well
> - Make test_invalid_parameters test the new method
> - Add a test to ensure that it's safe to fall back to scanline decoding without
> rewinding
>
> BUG=skia:4211
>
> The new version was generally faster than the old version (but not significantly so).
>
> Some raw performance differences can be found at https://docs.google.com/a/google.com/spreadsheets/d/1Gis3aRCEa72qBNDRMgGDg3jD-pMgO-FXldlNF9ejo4o/
>
> Design doc can be found at https://docs.google.com/a/google.com/document/d/11Mn8-ePDKwVEMCjs3nWwSjxcSpJ_Cu8DF57KNtUmgLM/
>
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1997703003
>
> Committed: https://skia.googlesource.com/skia/+/a4b09a117d4d1ba5dda372e6a2323e653766539e
>
> Committed: https://skia.googlesource.com/skia/+/30e78c9737ff4861dc4e3fa1e4cd010680ed6965
>
> Committed: https://skia.googlesource.com/skia/+/6fb2391b2cc83ee2160b4e994faa8128975acc1fTBR=reed@google.com,msarett@google.com,scroggo@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=skia:4211
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2044573002
Review-Url: https://codereview.chromium.org/2044573002
This is a step towards using SkCodec in Chromium, where progressive
decoding is necessary.
Switch from using png_read_row (which expects all the data to be
available) to png_process_data, which uses callbacks when rows are
available.
Create a new API for SkCodec, which supports progressive decoding and
scanline decoding. Future changes will switch the other clients off of
startScanlineDecode and get/skip-Scanlines to the new API.
Remove SkCodec::kNone_ScanlineOrder, which was only used for interlaced
PNG images. In the new API, interlaced PNG fits kTopDown. Also remove
updateCurrScanline(), which was only used by the old implementation for
interlaced PNG.
DMSrcSink:
- In CodecSrc::kScanline_Mode, use the new method for scanline decoding
for the supported formats (just PNG and PNG-in-ICO for now).
fuzz.cpp:
- Remove reference to kNone_ScanlineOrder
SkCodec:
- Add new APIs:
- startIncrementalDecode
- incrementalDecode
- Remove kNone_SkScanlineOrder and updateCurrScanline()
SkPngCodec:
- Implement new APIs
- Switch from sk_read_fn/png_read_row etc to png_process_data
- Expand AutoCleanPng's role to decode the header and create the
SkPngCodec
- Make the interlaced PNG decoder report how many lines were
initialized during an incomplete decode
- Make initializeSwizzler return a bool instead of an SkCodec::Result
(It only returned kSuccess or kInvalidInput anyway)
SkIcoCodec:
- Implement the new APIs; supported for PNG in ICO
SkSampledCodec:
- Call the new method for decoding scanlines, and fall back to the old
method if the new version is unimplemented
- Remove references to kNone_SkScanlineOrder
tests/CodecPartial:
- Add a test which decodes part of an image, then finishes the decode,
and compares it to the straightforward method
tests/CodecTest:
- Add a test which decodes all scanlines using the new method
- Repurpose the Codec_stripes test to decode using the new method in
sections rather than all at once
- In the method check(), add a parameter for whether the image supports
the new method of scanline decoding, and be explicit about whether an
image supports incomplete
- Test incomplete PNG decodes. We should have been doing it anyway for
non-interlaced (except for an image that is too small - one row), but
the new method supports interlaced incomplete as well
- Make test_invalid_parameters test the new method
- Add a test to ensure that it's safe to fall back to scanline decoding without
rewinding
BUG=skia:4211
The new version was generally faster than the old version (but not significantly so).
Some raw performance differences can be found at https://docs.google.com/a/google.com/spreadsheets/d/1Gis3aRCEa72qBNDRMgGDg3jD-pMgO-FXldlNF9ejo4o/
Design doc can be found at https://docs.google.com/a/google.com/document/d/11Mn8-ePDKwVEMCjs3nWwSjxcSpJ_Cu8DF57KNtUmgLM/
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1997703003
Committed: https://skia.googlesource.com/skia/+/a4b09a117d4d1ba5dda372e6a2323e653766539e
Committed: https://skia.googlesource.com/skia/+/30e78c9737ff4861dc4e3fa1e4cd010680ed6965
Review-Url: https://codereview.chromium.org/1997703003
Reason for revert:
Still breaking Google3 e.g.:
https://sponge.corp.google.com/target?id=9261d31b-34fc-4f0f-981e-f92f7c5cea2c&target=//third_party/skia/HEAD:dm#shard=1|run=1|attempt=1|page=-1
https://test.corp.google.com/ui#cl=123773095&flags=CAMQBQ==&id=OCL:123773095:BASE:123773415:1464804876959:b0ea9b1c&t=//third_party/skia/HEAD:dm
Original issue's description:
> Make SkPngCodec decode progressively.
>
> This is a step towards using SkCodec in Chromium, where progressive
> decoding is necessary.
>
> Switch from using png_read_row (which expects all the data to be
> available) to png_process_data, which uses callbacks when rows are
> available.
>
> Create a new API for SkCodec, which supports progressive decoding and
> scanline decoding. Future changes will switch the other clients off of
> startScanlineDecode and get/skip-Scanlines to the new API.
>
> Remove SkCodec::kNone_ScanlineOrder, which was only used for interlaced
> PNG images. In the new API, interlaced PNG fits kTopDown. Also remove
> updateCurrScanline(), which was only used by the old implementation for
> interlaced PNG.
>
> DMSrcSink:
> - In CodecSrc::kScanline_Mode, use the new method for scanline decoding
> for the supported formats (just PNG and PNG-in-ICO for now).
>
> fuzz.cpp:
> - Remove reference to kNone_ScanlineOrder
>
> SkCodec:
> - Add new APIs:
> - startIncrementalDecode
> - incrementalDecode
> - Remove kNone_SkScanlineOrder and updateCurrScanline()
>
> SkPngCodec:
> - Implement new APIs
> - Switch from sk_read_fn/png_read_row etc to png_process_data
> - Expand AutoCleanPng's role to decode the header and create the
> SkPngCodec
> - Make the interlaced PNG decoder report how many lines were
> initialized during an incomplete decode
> - Make initializeSwizzler return a bool instead of an SkCodec::Result
> (It only returned kSuccess or kInvalidInput anyway)
>
> SkIcoCodec:
> - Implement the new APIs; supported for PNG in ICO
>
> SkSampledCodec:
> - Call the new method for decoding scanlines, and fall back to the old
> method if the new version is unimplemented
> - Remove references to kNone_SkScanlineOrder
>
> tests/CodecPartial:
> - Add a test which decodes part of an image, then finishes the decode,
> and compares it to the straightforward method
>
> tests/CodecTest:
> - Add a test which decodes all scanlines using the new method
> - Repurpose the Codec_stripes test to decode using the new method in
> sections rather than all at once
> - In the method check(), add a parameter for whether the image supports
> the new method of scanline decoding, and be explicit about whether an
> image supports incomplete
> - Test incomplete PNG decodes. We should have been doing it anyway for
> non-interlaced (except for an image that is too small - one row), but
> the new method supports interlaced incomplete as well
> - Make test_invalid_parameters test the new method
> - Add a test to ensure that it's safe to fall back to scanline decoding without
> rewinding
>
> BUG=skia:4211
>
> The new version was generally faster than the old version (but not significantly so).
>
> Some raw performance differences can be found at https://docs.google.com/a/google.com/spreadsheets/d/1Gis3aRCEa72qBNDRMgGDg3jD-pMgO-FXldlNF9ejo4o/
>
> Design doc can be found at https://docs.google.com/a/google.com/document/d/11Mn8-ePDKwVEMCjs3nWwSjxcSpJ_Cu8DF57KNtUmgLM/
>
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1997703003
>
> Committed: https://skia.googlesource.com/skia/+/a4b09a117d4d1ba5dda372e6a2323e653766539e
>
> Committed: https://skia.googlesource.com/skia/+/30e78c9737ff4861dc4e3fa1e4cd010680ed6965TBR=reed@google.com,msarett@google.com,scroggo@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:4211
Review-Url: https://codereview.chromium.org/2026383002
This is a step towards using SkCodec in Chromium, where progressive
decoding is necessary.
Switch from using png_read_row (which expects all the data to be
available) to png_process_data, which uses callbacks when rows are
available.
Create a new API for SkCodec, which supports progressive decoding and
scanline decoding. Future changes will switch the other clients off of
startScanlineDecode and get/skip-Scanlines to the new API.
Remove SkCodec::kNone_ScanlineOrder, which was only used for interlaced
PNG images. In the new API, interlaced PNG fits kTopDown. Also remove
updateCurrScanline(), which was only used by the old implementation for
interlaced PNG.
DMSrcSink:
- In CodecSrc::kScanline_Mode, use the new method for scanline decoding
for the supported formats (just PNG and PNG-in-ICO for now).
fuzz.cpp:
- Remove reference to kNone_ScanlineOrder
SkCodec:
- Add new APIs:
- startIncrementalDecode
- incrementalDecode
- Remove kNone_SkScanlineOrder and updateCurrScanline()
SkPngCodec:
- Implement new APIs
- Switch from sk_read_fn/png_read_row etc to png_process_data
- Expand AutoCleanPng's role to decode the header and create the
SkPngCodec
- Make the interlaced PNG decoder report how many lines were
initialized during an incomplete decode
- Make initializeSwizzler return a bool instead of an SkCodec::Result
(It only returned kSuccess or kInvalidInput anyway)
SkIcoCodec:
- Implement the new APIs; supported for PNG in ICO
SkSampledCodec:
- Call the new method for decoding scanlines, and fall back to the old
method if the new version is unimplemented
- Remove references to kNone_SkScanlineOrder
tests/CodecPartial:
- Add a test which decodes part of an image, then finishes the decode,
and compares it to the straightforward method
tests/CodecTest:
- Add a test which decodes all scanlines using the new method
- Repurpose the Codec_stripes test to decode using the new method in
sections rather than all at once
- In the method check(), add a parameter for whether the image supports
the new method of scanline decoding, and be explicit about whether an
image supports incomplete
- Test incomplete PNG decodes. We should have been doing it anyway for
non-interlaced (except for an image that is too small - one row), but
the new method supports interlaced incomplete as well
- Make test_invalid_parameters test the new method
- Add a test to ensure that it's safe to fall back to scanline decoding without
rewinding
BUG=skia:4211
The new version was generally faster than the old version (but not significantly so).
Some raw performance differences can be found at https://docs.google.com/a/google.com/spreadsheets/d/1Gis3aRCEa72qBNDRMgGDg3jD-pMgO-FXldlNF9ejo4o/
Design doc can be found at https://docs.google.com/a/google.com/document/d/11Mn8-ePDKwVEMCjs3nWwSjxcSpJ_Cu8DF57KNtUmgLM/
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1997703003
Committed: https://skia.googlesource.com/skia/+/a4b09a117d4d1ba5dda372e6a2323e653766539e
Review-Url: https://codereview.chromium.org/1997703003
Reason for revert:
This is failing tests and then crashing on Google3 [1]. The crashes are fixed by crrev.com/2026873002, but to fix the builder we'll need to upgrade its version of libpng.
[1] https://sponge.corp.google.com/target?id=e545ef55-4da4-4931-9524-1ac92acb61b1&target=//third_party/skia/HEAD:dm#shard=1|run=1|attempt=1|page=-1
Original issue's description:
> Make SkPngCodec decode progressively.
>
> This is a step towards using SkCodec in Chromium, where progressive
> decoding is necessary.
>
> Switch from using png_read_row (which expects all the data to be
> available) to png_process_data, which uses callbacks when rows are
> available.
>
> Create a new API for SkCodec, which supports progressive decoding and
> scanline decoding. Future changes will switch the other clients off of
> startScanlineDecode and get/skip-Scanlines to the new API.
>
> Remove SkCodec::kNone_ScanlineOrder, which was only used for interlaced
> PNG images. In the new API, interlaced PNG fits kTopDown. Also remove
> updateCurrScanline(), which was only used by the old implementation for
> interlaced PNG.
>
> DMSrcSink:
> - In CodecSrc::kScanline_Mode, use the new method for scanline decoding
> for the supported formats (just PNG and PNG-in-ICO for now).
>
> fuzz.cpp:
> - Remove reference to kNone_ScanlineOrder
>
> SkCodec:
> - Add new APIs:
> - startIncrementalDecode
> - incrementalDecode
> - Remove kNone_SkScanlineOrder and updateCurrScanline()
>
> SkPngCodec:
> - Implement new APIs
> - Switch from sk_read_fn/png_read_row etc to png_process_data
> - Expand AutoCleanPng's role to decode the header and create the
> SkPngCodec
> - Make the interlaced PNG decoder report how many lines were
> initialized during an incomplete decode
> - Make initializeSwizzler return a bool instead of an SkCodec::Result
> (It only returned kSuccess or kInvalidInput anyway)
>
> SkIcoCodec:
> - Implement the new APIs; supported for PNG in ICO
>
> SkSampledCodec:
> - Call the new method for decoding scanlines, and fall back to the old
> method if the new version is unimplemented
> - Remove references to kNone_SkScanlineOrder
>
> tests/CodecPartial:
> - Add a test which decodes part of an image, then finishes the decode,
> and compares it to the straightforward method
>
> tests/CodecTest:
> - Add a test which decodes all scanlines using the new method
> - Repurpose the Codec_stripes test to decode using the new method in
> sections rather than all at once
> - In the method check(), add a parameter for whether the image supports
> the new method of scanline decoding, and be explicit about whether an
> image supports incomplete
> - Test incomplete PNG decodes. We should have been doing it anyway for
> non-interlaced (except for an image that is too small - one row), but
> the new method supports interlaced incomplete as well
> - Make test_invalid_parameters test the new method
> - Add a test to ensure that it's safe to fall back to scanline decoding without
> rewinding
>
> BUG=skia:4211
>
> The new version was generally faster than the old version (but not significantly so).
>
> Some raw performance differences can be found at https://docs.google.com/a/google.com/spreadsheets/d/1Gis3aRCEa72qBNDRMgGDg3jD-pMgO-FXldlNF9ejo4o/
>
> Design doc can be found at https://docs.google.com/a/google.com/document/d/11Mn8-ePDKwVEMCjs3nWwSjxcSpJ_Cu8DF57KNtUmgLM/
>
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1997703003
>
> Committed: https://skia.googlesource.com/skia/+/a4b09a117d4d1ba5dda372e6a2323e653766539eTBR=reed@google.com,msarett@google.com,scroggo@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:4211
Review-Url: https://codereview.chromium.org/2023103002
This is a step towards using SkCodec in Chromium, where progressive
decoding is necessary.
Switch from using png_read_row (which expects all the data to be
available) to png_process_data, which uses callbacks when rows are
available.
Create a new API for SkCodec, which supports progressive decoding and
scanline decoding. Future changes will switch the other clients off of
startScanlineDecode and get/skip-Scanlines to the new API.
Remove SkCodec::kNone_ScanlineOrder, which was only used for interlaced
PNG images. In the new API, interlaced PNG fits kTopDown. Also remove
updateCurrScanline(), which was only used by the old implementation for
interlaced PNG.
DMSrcSink:
- In CodecSrc::kScanline_Mode, use the new method for scanline decoding
for the supported formats (just PNG and PNG-in-ICO for now).
fuzz.cpp:
- Remove reference to kNone_ScanlineOrder
SkCodec:
- Add new APIs:
- startIncrementalDecode
- incrementalDecode
- Remove kNone_SkScanlineOrder and updateCurrScanline()
SkPngCodec:
- Implement new APIs
- Switch from sk_read_fn/png_read_row etc to png_process_data
- Expand AutoCleanPng's role to decode the header and create the
SkPngCodec
- Make the interlaced PNG decoder report how many lines were
initialized during an incomplete decode
- Make initializeSwizzler return a bool instead of an SkCodec::Result
(It only returned kSuccess or kInvalidInput anyway)
SkIcoCodec:
- Implement the new APIs; supported for PNG in ICO
SkSampledCodec:
- Call the new method for decoding scanlines, and fall back to the old
method if the new version is unimplemented
- Remove references to kNone_SkScanlineOrder
tests/CodecPartial:
- Add a test which decodes part of an image, then finishes the decode,
and compares it to the straightforward method
tests/CodecTest:
- Add a test which decodes all scanlines using the new method
- Repurpose the Codec_stripes test to decode using the new method in
sections rather than all at once
- In the method check(), add a parameter for whether the image supports
the new method of scanline decoding, and be explicit about whether an
image supports incomplete
- Test incomplete PNG decodes. We should have been doing it anyway for
non-interlaced (except for an image that is too small - one row), but
the new method supports interlaced incomplete as well
- Make test_invalid_parameters test the new method
- Add a test to ensure that it's safe to fall back to scanline decoding without
rewinding
BUG=skia:4211
The new version was generally faster than the old version (but not significantly so).
Some raw performance differences can be found at https://docs.google.com/a/google.com/spreadsheets/d/1Gis3aRCEa72qBNDRMgGDg3jD-pMgO-FXldlNF9ejo4o/
Design doc can be found at https://docs.google.com/a/google.com/document/d/11Mn8-ePDKwVEMCjs3nWwSjxcSpJ_Cu8DF57KNtUmgLM/
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1997703003
Review-Url: https://codereview.chromium.org/1997703003
