Commit Graph

40 Commits

Author SHA1 Message Date
Cary Clark
7eb01e00b1 simplify bug
The path contains a cubic with a very tight curve.
Split the cubic into pieces so that the individual
curves are better behaved.

Use both inflections and max curvature to 
potentially split cubics. Since this may require
a bit of work, preflight to ignore cubics that
monotonically change in x and y.

Only one of the three tests referred to by the bug
below repro'd. Use path.dumpHex() instead of 
path.dump() to capture the crashing data.

TBR=reed@google.com
BUG=skia:6041

Change-Id: I29a264f87242cacc7c421e7685b90aca81621c74
Reviewed-on: https://skia-review.googlesource.com/5702
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>
2016-12-08 20:29:37 +00:00
caryclark
34efb70398 nc seal breaks simplify
This test has nearly coincident lines that are missorted.
The underlying bug is caused when a pair of curves
are coincident when reduced to line segments, but the
end points aren't detected.

The error was generated by running nanobench over all svg
sample data with the distance field patch installed.

TBR=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2440043003

Review-Url: https://codereview.chromium.org/2440043003
2016-10-24 08:19:07 -07:00
caryclark
78a37a5336 fix more fuzz, carsvg
Fix a few kevin-generated fuzzers.

Remove an assert triggered by
carsvg when thrown through the
distance field stuff.

TBR=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2427253005

Review-Url: https://chromiumcodereview.appspot.com/2427253005
2016-10-20 12:36:16 -07:00
caryclark
b36a3cd137 break ambiguous angle sorting loop
A pair of cubics may be difficult to sort if the tangents suggest
one sort but the midpoints suggest a different one. When in this
gray area, and when the cumulative sort of all the angles fails to
resolve, reverse the sort to break the tie.

Before, when tiger8 was run through the signed distance field
generated directly from the path data, the simplify call might
hang since the angle could not be resolved. If the endless loop
is detected, and if there is no tie to break, just fail instead.

TBR=reed@google.com
BUG=skia:5131
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2426753002

Review-Url: https://codereview.chromium.org/2426753002
2016-10-18 07:59:44 -07:00
caryclark
6c3b9cdcb0 fix tiger b
The tiger tests have uncovered numerous bugs.
This CL fixes the last of them.

If a pair of curves do not intersect, but
have one or both ends very close to the opposite
curve, consider that an intersection.

TBR=reed@google.com
BUG=skia:5131
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2356363003

Review-Url: https://codereview.chromium.org/2356363003
2016-09-26 05:36:58 -07:00
caryclark
27c015dfcf split tight quads and conics
Tight quads and conics may nearly fold over on themselves, confusing
coincidence against other curves. Split them at their max curvature
early on to avoid complicating later logic.

TBR=reed@google.com
BUG=skia:5131
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2357353002

Review-Url: https://codereview.chromium.org/2357353002
2016-09-23 05:47:20 -07:00
caryclark
e839e78443 quad and conic do not intersect
If a quad a conic intersect only where the end of one
is contained by the convex hull of the other, and the
curve contained by the hull is nearly a straight line,
treating it as a line may move the end point to the
other side of the curve.

Detect this by checking to see if the end point is in
the hull, and if so, continue to subdivide the curve
rather than treating it as a line.

This fixes several existing tests that were disabled
earlier this year.

A typo in SkDCurve::nearPoint() prevented detecting when
the end of a line was nearly touching a curve.

Also fixed concidence a bit to get the second half of
tiger further along.

All existing tests, including extended testing in
Release and the first half of tiger, work.

TBR=reed@google.com
BUG=skia:5131
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2338323002

Review-Url: https://codereview.chromium.org/2338323002
2016-09-15 07:48:18 -07:00
caryclark
81a478ca6c Skip adding coincident edges found
during curve intersection if their
ends are nearly the same.

Loosen conic/line intersection point
check.

Detect when coincident points are
unordered. This means that points
a/b/c on one curve may appear in
b/c/a order on the opposite curve.

Restructure addMissing to return
success and return if a coincidence
was added as a parameter.

With this, tiger part a works.
Tiger part b exposes bugs around
tight quads that are nearly coincident
with themselves, and are coincident
with something else.

The greedy coicident matcher
may cause the point order to be
out of sync.

Still working out what to do in
this case.

TBR=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2321773002

Review-Url: https://codereview.chromium.org/2321773002
2016-09-09 09:37:57 -07:00
caryclark
8016b264ce interpolation of coincidence must be local to a single span
Pathops makes up intersections that it doesn't detect directly,
but do exist. For instance, if a is coincident with b, and
b is coincident with c, then for where they overlap
a is coincident with c.

The intersections are made up in different ways. In a few
places, the t values that are detected are interpolated to
guess the t values that represent invented intersections.

The interpolated t is not necessarily linear, but a linear
guess is good enough if the invented t lies between known
t values.

Additionally, improve debugging.

This passes the extended release test suite and additionally
passes the first 17 levels in the tiger test suite;
previously, path ops passed 7 levels.

The tiger suite is composed of 37 levels in increasing
complexity, described by about 300K tests.

TBR=reed@google.com
BUG=skia:5131
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2300203002

Review-Url: https://codereview.chromium.org/2300203002
2016-09-06 05:59:47 -07:00
caryclark
30b9fdd6a1 pathops coincident work
This is working towards fixing all bugs around simplifying the tiger.

This installment simplifies the point-t intersection list as it is built rather than doing the analysis once the intersections are complete. This avoids getting the list in an inconsistent state and makes coincident checks faster and more stable.

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2237223002

TBR=reed@google.com
BUG=skia:5131

Review-Url: https://codereview.chromium.org/2237223002
2016-08-31 14:36:30 -07:00
caryclark
81681949d3 allow curves on side of lines to be very small
Increase the precision of the 'all on one side' pathops
angle test to reduce the number of unorderable segments
found by the cubics_d3 test.

This allows pathsops_unittest release build with -v -V -x
to run without error.

TBR=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2168163002

Review-Url: https://codereview.chromium.org/2168163002
2016-07-21 10:44:07 -07:00
caryclark
55888e4417 pathops coincidence and security rewrite
Most changes stem from working on an examples bracketed
by #if DEBUG_UNDER_DEVELOPMENT  // tiger
These exposed many problems with coincident curves,
as well as errors throughout the code.

Fixing these errors also fixed a number of fuzzer-inspired
bug reports.

* Line/Curve Intersections
Check to see if the end of the line nearly intersects
the curve. This was a FIXME in the old code.

* Performance
Use a central chunk allocator.
Plumb the allocator into the global variable state
so that it can be shared. (Note that 'SkGlobalState'
is allocated on the stack and is visible to children
functions but not other threads.)

* Refactor
Let SkOpAngle grow up from a structure to a class.
Let SkCoincidentSpans grow up from a structure to a class.
Rename enum Alias to AliasMatch.

* Coincidence Rewrite
Add more debugging to coincidence detection.
Parallel debugging routines have read-only logic to report
the current coincidence state so that steps through the
logic can expose whether things got better or worse.

More functions can error-out and cause the pathops
engine to non-destructively exit.

* Accuracy
Remove code that adjusted point locations. Instead,
offset the curve part so that sorted curves all use
the same origin.
Reduce the size (and influence) of magic numbers.

* Testing
The debug suite with verify and the full release suite
./out/Debug/pathops_unittest -v -V
./out/Release/pathops_unittest -v -V -x
expose one error. That error is captured as cubics_d3.
This error exists in the checked in code as well.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2128633003

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2128633003

Review-Url: https://codereview.chromium.org/2128633003
2016-07-18 10:01:36 -07:00
caryclark
ef784fb7f5 More conic-specific tests revealed a few conic-specific bugs. Because javascript / canvas make visualizing conics tricky, new native tools are required.
The utility SubsetPath removes parts of a potentially very large path to isolate a minimal test case. SubsetPath is very useful for debugging path ops, but is not path ops specific.

PathOpsBuilderConicTest compares the output of the Path Ops Builder, sequential calls to Simplify, and SkRegions for some number of rotated ovals.

Some tests caused path ops to hang. It was caught adding a loop of curves because the head was not found by the tail. Even though the root cause has been fixed, SkSegment::addCurveTo callers now abort the path op if the same curve was added twice.

The subdivided conic weight was been computed anew. Fortunately, it's a simpler computation that the one it replaces.

Some Simplify() subroutines returned false to signal that the results needed assembling. Change these to abort the current operation instead.

Coincident curve intersection triggered two small bugs; one where no perpendicular could be found for coincident curves, and one where no coincident curves remain after looping.

The SixtyOvals test can be run through multiple processes instead of multiple threads. This strategy allows a 48 core machine to saturate all cores at 100%.

The DEBUG_VISUALIZE_CONICS code in PathOpsConicIntersectionTest acknowleges that it is easier to visualize conics with Skia than with script and html canvas. This test also verifies that path ops subdivision matches geometry chopping.

TBR=reed@google.com

Review URL: https://codereview.chromium.org/1405383004
2015-10-30 12:03:06 -07:00
caryclark
ed0935a28a Reland of path ops: fix conic weight and partial coincidence (patchset #1 id:1 of https://codereview.chromium.org/1408923003/ )
Reason for revert:
suppressions have landed in chrome

Original issue's description:
> Revert of path ops: fix conic weight and partial coincidence (patchset #5 id:80001 of https://codereview.chromium.org/1413763002/ )
>
> Reason for revert:
> path ops change breaks svg clipping layout tests -- conic is now more accurate, changing edge of circle in clip
>
> These need to be rebaselined
>
> svg/clip-path/clip-path-child-clipped.svg
> svg/clip-path/clip-path-nonzero.svg
> svg/clip-path/clip-path-evenodd-nonzero.svg
> svg/clip-path/clip-path-nonzero-evenodd.svg
>
> Original issue's description:
> > The remaining 1m skp bugs are asserts that can be harmlessly
> > suppressed and bugs around conics.
> >
> > The conic calculation for a subdivided w was just wrong.
> >
> > Also added debugging to template intersection to initialize
> > reused structures and dump additional data.
> >
> > TBR=reed@google.com
> >
> > Committed: https://skia.googlesource.com/skia/+/ef33b1e739b23a1201100ff17a572da85b03d9af
>
> TBR=
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
>
> Committed: https://skia.googlesource.com/skia/+/f428df1be3e96d3f8970d0f7f415b862f7da5404

TBR=
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1407003016
2015-10-22 07:23:52 -07:00
caryclark
f428df1be3 Revert of path ops: fix conic weight and partial coincidence (patchset #5 id:80001 of https://codereview.chromium.org/1413763002/ )
Reason for revert:
path ops change breaks svg clipping layout tests -- conic is now more accurate, changing edge of circle in clip

These need to be rebaselined

svg/clip-path/clip-path-child-clipped.svg
svg/clip-path/clip-path-nonzero.svg
svg/clip-path/clip-path-evenodd-nonzero.svg
svg/clip-path/clip-path-nonzero-evenodd.svg

Original issue's description:
> The remaining 1m skp bugs are asserts that can be harmlessly
> suppressed and bugs around conics.
>
> The conic calculation for a subdivided w was just wrong.
>
> Also added debugging to template intersection to initialize
> reused structures and dump additional data.
>
> TBR=reed@google.com
>
> Committed: https://skia.googlesource.com/skia/+/ef33b1e739b23a1201100ff17a572da85b03d9af

TBR=
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1408923003
2015-10-21 04:02:51 -07:00
caryclark
ef33b1e739 The remaining 1m skp bugs are asserts that can be harmlessly
suppressed and bugs around conics.

The conic calculation for a subdivided w was just wrong.

Also added debugging to template intersection to initialize
reused structures and dump additional data.

TBR=reed@google.com

Review URL: https://codereview.chromium.org/1413763002
2015-10-20 13:42:25 -07:00
caryclark
26ad22ab61 Enabling clip stack flattening exercises path ops.
Iterating through the 903K skps that represent the
imagable 1M top web pages triggers a number of
bugs, some of which are addressed here.

Some web pages trigger intersecting cubic
representations of arc with their conic
counterparts. This exposed a flaw in coincident
detection that caused an infinite loop. The loop
alternatively extended the coincident section and,
determining the that the bounds of the curve pairs
did not overlap, deleted the extension.

Track the number of times the coincident detection
is called, and if it exceeds an empirically found
limit, assume that the curves are coincident and
force it to be so.

The loop count limit can be determined by enabling
DEBUG_T_SECT_LOOP_COUNT and running all tests. The
largest count is reported on completion.

Another class of bugs was caused by concident
detection duplicating nearly identical points that
had been merged earlier. To track these bugs, the
'handle coincidence' code was duplicated as a
const debug variety that reported if one of a
dozen or so irregularities are present; then it is
easier to see when a block of code that fixes one
irregularity regresses another.

Creating the debug const code version exposed some
non-debug code that could be const, and some that
was experimental and could be removed. Set
DEBUG_COINCIDENCE to track coincidence health and
handling.

For running on Chrome, DEBUG_VERIFY checks the
result of pathops against the same operation
using SkRegion to verify that the results are
nearly the same.

When visualizing the pathops work using
tools/pathops_visualizer.htm, set
DEBUG_DUMP_ALIGNMENT to see the curves after
they've been aligned for coincidence.

Other bugs fixed include detecting when a
section of a pair of curves have devolved into
lines and are coincident.

TBR=reed@google.com

Review URL: https://codereview.chromium.org/1394503003
2015-10-16 09:03:38 -07:00
caryclark
fc95be17c3 fix pathops battle test
The intermediate subtraction threw away bits causing
the subsequent cross product to fail. Defer the
bit truncation until after the vector is computed.

TBR=reed@google.com

Review URL: https://codereview.chromium.org/1226933003
2015-07-07 18:09:32 -07:00
caryclark
27c8eb8ffd When three or more edges are coincident, the logic needs
to compute the overlapping ranges and combine the winding
into a single destination.

This computes coincidence more rigorously, fixing the
edge cases exposed by this bug.

Also, add the ability to debug and dump pathop structures
from the coincident context.

TBR=reed@google.com
BUG=skia:3651

Review URL: https://codereview.chromium.org/1182493015
2015-07-06 11:38:33 -07:00
caryclark
612f70d5fa handle large conic strokes better
A stroked conic computes the outset quad's control point by
computing the intersection of the quad's endpoints. If the
the denominator used to compute the scale factor for the
control point is small, check to see if the numerator is also
small so that the division stays bounded.

Also clean up error returns and internal function calls to
simplify the code.

Additionally, remove comic max curvature (unimplemented) and call
extrema functions instead to handle cases where the conic is degenerate
or is a line.

R=reed@google.com, fmalita@chromium.org
BUG=skia:3843

Review URL: https://codereview.chromium.org/1144883003
2015-05-19 11:05:37 -07:00
caryclark
bca19f7747 deal more consistently with unsortable edges
Improve line/curve coincident detection and resolution. This fixed the remaining simple failures.

When an edge is unsortable, use the ray intersection to determine the angles' winding.

Deal with degenerate segments.

TBR=reed@google.com
BUG=skia:3588,skia:3762

Review URL: https://codereview.chromium.org/1140813002
2015-05-13 08:23:48 -07:00
caryclark
624637cc8e Path ops formerly found the topmost unprocessed edge and determined its angle sort order to initialize the winding. This never worked correctly with cubics and was flaky with paths consisting mostly of vertical edges.
This replacement shoots axis-aligned rays through all intersecting edges to find the outermost one either horizontally or vertically. The resulting code is smaller and twice as fast.

To support this, most of the horizontal / vertical intersection code was rewritten and standardized, and old code supporting the top-directed winding was deleted.

Contours were pointed to by an SkTDArray. Instead, put them in a linked list, and designate the list head with its own class to ensure that methods that take lists of contours start at the top. This change removed a large percentage of memory allocations used by path ops.

TBR=reed@google.com
BUG=skia:3588

Review URL: https://codereview.chromium.org/1111333002
2015-05-11 07:21:28 -07:00
caryclark
aec2510125 minor fixes to cubics code and overall alignment of how bounds and tops are computed for all curve types
All but 17 extended tests work.

A helper function is privately added to SkPath.h to permit a test to modify a given point in a path.

BUG=skia:3588

Review URL: https://codereview.chromium.org/1107353004
2015-04-29 08:28:30 -07:00
caryclark
08bc8488fa fix multiple intersection logic
When three or more curves intersect at the same point, ensure that
each curve records the intersections of the others. This fixes a
number of cubic tests.

TBR=reed@google.com
BUG=skia:3588

Review URL: https://codereview.chromium.org/1105943002
2015-04-24 09:08:57 -07:00
caryclark
03b03cad01 working on initial winding for cubics
Path ops works well for all tests except for cubics.
Isolate failures caused by cubics, and do a better job of computing
the initial winding for cubics.

TBR=reed@google.com
BUG=skia:3588

Review URL: https://codereview.chromium.org/1096923003
2015-04-23 09:13:37 -07:00
caryclark
1049f1246e Now, path ops natively intersect conics, quads, and cubics in any combination. There are still a class of cubic tests that fail and a handful of undiagnosed failures from skps and fuzz tests, but things are much better overall.
Extended tests (150M+) run to completion in release in about 6 minutes; the standard test suite exceeds 100K and finishes in a few seconds on desktops.

TBR=reed
BUG=skia:3588

Review URL: https://codereview.chromium.org/1037953004
2015-04-20 08:31:59 -07:00
caryclark
54359294a7 cumulative pathops patch
Replace the implicit curve intersection with a geometric curve intersection. The implicit intersection proved mathematically unstable and took a long time to zero in on an answer.

Use pointers instead of indices to refer to parts of curves. Indices required awkward renumbering.

Unify t and point values so that small intervals can be eliminated in one pass.

Break cubics up front to eliminate loops and cusps.

Make the Simplify and Op code more regular and eliminate arbitrary differences.

Add a builder that takes an array of paths and operators.

Delete unused code.

BUG=skia:3588
R=reed@google.com

Review URL: https://codereview.chromium.org/1037573004
2015-03-26 07:52:43 -07:00
reed
0dc4dd6dda Revert of pathops version two (patchset #16 id:150001 of https://codereview.chromium.org/1002693002/)
Reason for revert:
ASAN investigation

Original issue's description:
> pathops version two
>
> R=reed@google.com
>
> marked 'no commit' to attempt to get trybots to run
>
> TBR=reed@google.com
>
> Committed: https://skia.googlesource.com/skia/+/ccec0f958ffc71a9986d236bc2eb335cb2111119

TBR=caryclark@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1029993002
2015-03-24 13:55:33 -07:00
caryclark
ccec0f958f pathops version two
R=reed@google.com

marked 'no commit' to attempt to get trybots to run

TBR=reed@google.com

Review URL: https://codereview.chromium.org/1002693002
2015-03-24 07:28:17 -07:00
caryclark
65f553182a These tests stress pathops by describing the union of circle-like paths that have tiny line segments embedded and double back to create near-coincident conditions.
The fixes include
- detect when finding the active top loops between two possible answers
- preflight chasing winding to ensure answer is consistent
- binary search more often when quadratic intersection fails
- add more failure paths when an intersect is missed

While this fixes the chrome bug, reenabling path ops in svg should be deferred until additional fixes are landed.

TBR=
BUG=421132

Committed: https://skia.googlesource.com/skia/+/6f726addf3178b01949bb389ef83cf14a1d7b6b2

Review URL: https://codereview.chromium.org/633393002
2014-11-13 06:58:52 -08:00
hcm
27c46a08a9 Revert of harden pathops for pathological test (patchset #19 id:410001 of https://codereview.chromium.org/633393002/)
Reason for revert:
Compile errors on bots

Original issue's description:
> These tests stress pathops by describing the union of circle-like paths that have tiny line segments embedded and double back to create near-coincident conditions.
>
> The fixes include
> - detect when finding the active top loops between two possible answers
> - preflight chasing winding to ensure answer is consistent
> - binary search more often when quadratic intersection fails
> - add more failure paths when an intersect is missed
>
> While this fixes the chrome bug, reenabling path ops in svg should be deferred until additional fixes are landed.
>
> TBR=
> BUG=421132
>
> Committed: https://skia.googlesource.com/skia/+/6f726addf3178b01949bb389ef83cf14a1d7b6b2

TBR=caryclark@google.com
NOTREECHECKS=true
NOTRY=true
BUG=421132

Review URL: https://codereview.chromium.org/686843002
2014-10-28 10:55:54 -07:00
caryclark
6f726addf3 These tests stress pathops by describing the union of circle-like paths that have tiny line segments embedded and double back to create near-coincident conditions.
The fixes include
- detect when finding the active top loops between two possible answers
- preflight chasing winding to ensure answer is consistent
- binary search more often when quadratic intersection fails
- add more failure paths when an intersect is missed

While this fixes the chrome bug, reenabling path ops in svg should be deferred until additional fixes are landed.

TBR=
BUG=421132

Review URL: https://codereview.chromium.org/633393002
2014-10-28 10:33:09 -07:00
caryclark
65b427cff9 fix battlefield website by disallowing very small coordinates
also add and remove comments to document other attempts to fix this that had drawbacks

R=fmalita@chromium.org
BUG=414409

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/575553003
2014-09-18 10:32:57 -07:00
caryclark
fa6d65619d add cubic red option to pathops tool
R=reed@google.com
TBR=reed@google.com
NOTREECHECKS=true
NOTRY=true

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/428963004
2014-07-29 12:13:28 -07:00
caryclark
19eb3b2f0a update pathops core and tests
split out skpclip (the test of 1M pictures) into its own project

TBR=reed

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/400033002
2014-07-18 05:08:14 -07:00
caryclark
e4097e3a0b Fix last pathops skp bug
This fixes the last bug discovered by iterating through the 800K
skp corpus representing the top 1M websites. For every clip on the
stack, the paths are replaced with the pathop intersection. The
resulting draw is compared with the original draw for pixel errors.

At least two prominent bugs remain. In one, the winding value is
confused by a cubic with an inflection. In the other, a quad/cubic
pair, nearly coincident, fails to find an intersection.

These minor changes include ignoring very tiny self-intersections
of cubics, and processing degenerate edges that don't connect to
anything else.

R=reed@android.com
TBR=reed

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/340103002
2014-06-18 07:24:19 -07:00
caryclark
dac1d17027 Enabling the canvas bit to turn the clip stack into a flat replace exposed around 100 failures when testing the 800K skp set generated from the top 1M web sites.
This fixes all but one of those failures.

Major changes include:
- Replace angle indices with angle pointers. This was motivated by the need to add angles later but not renumber existing angles.
- Aggressive segment chase. When the winding is known on a segment, more aggressively passing that winding to adjacent segments allows fragmented data sets to succeed.
- Line segments with ends nearly the same are treated as coincident first.
- Transfer partial coincidence by observing that if segment A is partially coincident to B and C then B and C may be partially coincident.

TBR=reed

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/272153002
2014-06-17 05:15:38 -07:00
commit-bot@chromium.org
2db7fe7d3b When solving the cubic line intersection directly fails, use binary search as a fallback.
The cubic line intersection math empirically works 99.99% of the time (fails 3100 out of 1B random tests) but when it fails, an intersection may be missed altogether.

The binary search is may not find a solution if the cubic line failed to find any solutions at all, but so far that case hasn't arisen.

BUG=skia:2504
TBR=reed@google.com

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/266063003

git-svn-id: http://skia.googlecode.com/svn/trunk@14614 2bbb7eff-a529-9590-31e7-b0007b416f81
2014-05-07 15:31:40 +00:00
commit-bot@chromium.org
8cb1daaa1e fix minor skp-found bugs
remove globals from pathops_unittest

BUG=skia:2460
TBR=mtklein

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/239563004

git-svn-id: http://skia.googlecode.com/svn/trunk@14378 2bbb7eff-a529-9590-31e7-b0007b416f81
2014-04-25 12:59:11 +00:00
commit-bot@chromium.org
4431e7757c Mike R: please sanity check SkPostConfig.h
Mike K: please sanity check Test.cpp and skia_test.cpp

Feel free to look at the rest, but I don't expect any in depth review of path ops innards.

Path Ops first iteration used QuickSort to order segments radiating from an intersection to compute the winding rule.

This revision uses a circular sort instead. Breaking out the circular sort into its own long-lived structure (SkOpAngle) allows doing less work and provides a home for caching additional sorting data.

The circle sort is more stable than the former sort, has a robust ordering and fewer exceptions. It finds unsortable ordering less often. It is less reliant on the initial curve  tangent, using convex hulls instead whenever it can.

Additional debug validation makes sure that the computed structures are self-consistent. A new visualization tool helps verify that the angle ordering is correct.

The 70+M tests pass with this change on Windows, Mac, Linux 32 and Linux 64 in debug and release.

R=mtklein@google.com, reed@google.com

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/131103009

git-svn-id: http://skia.googlecode.com/svn/trunk@14183 2bbb7eff-a529-9590-31e7-b0007b416f81
2014-04-14 17:08:59 +00:00