A pair of coincident lines can generate multiple intersection
points. Path ops is more stable when the intersection T value
is used to recompute the intersection point, but this has
the side-effect of making integral edges intersect at non-integral
values.
While it's worthwhile to fix this, for the moment it is less
disruptive to only worry about keeping intersection values
integral if the original intersection point is integral in
both axes.
Also, fix some debugging code that bit-rotted.
R=msarett@google.com
Change-Id: Iefd27b25d1d21c22b224c174bd59bc6c105033c4
Reviewed-on: https://skia-review.googlesource.com/13721
Reviewed-by: Matt Sarett <msarett@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>
corrupted intersection point lists
can loop forever. Add a safety
hatch to abort after a large number
of iterations.
TBR=kjlubick@google.com
BUG=700679
Change-Id: Ifd4b180b47ba3bbde38ade0bb13b16b8d645c1cb
Reviewed-on: https://skia-review.googlesource.com/9967
Reviewed-by: Cary Clark <caryclark@skia.org>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>
Prevent addEndMoveSpans from looping
forever and abort with an error
if the loop count is crazy big.
R=kjlubick@google.com
BUG=684553
Change-Id: I16c250c0b2f88534f809aba17a18081aea4e1f44
Reviewed-on: https://skia-review.googlesource.com/9458
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>
abort if incoming data is out of range
TBR=reed@google.com
BUG=676866
Change-Id: I7d4850611654a399e32ea2012b23ca369dc53e70
Reviewed-on: https://skia-review.googlesource.com/6525
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>
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>
The ASAN fuzzer on chrome caught a hanging state.
To capture the data, allow the pathops client debugging
to run in a release build.
TBR=reed@google.com
BUG=665295
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4834
Change-Id: I6b2c2baabd63994f63aa730d2ee7828986b5ab89
Reviewed-on: https://skia-review.googlesource.com/4834
Commit-Queue: Cary Clark <caryclark@google.com>
Reviewed-by: Cary Clark <caryclark@google.com>
Many old pathops-related fuzz failures have built up while
the codebase was under a state a flux. Now that the code
is stable, address these failures.
Most of the CL plumbs the debug global state to downstream
routines so that, if the data is not trusted (ala fuzzed)
the function can safely exit without asserting.
TBR=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2426173002
Review-Url: https://chromiumcodereview.appspot.com/2426173002
Error out when fuzzing
conditions are met.
Also, make degenerate
input line ends consistent.
TBR=reed@google.com
BUG=653452, 626164, skia:5829
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=3048
Change-Id: I23a01adde9dec07b54d66ab2418b3ea0b96e4456
Reviewed-on: https://skia-review.googlesource.com/3048
Commit-Queue: Cary Clark <caryclark@google.com>
Reviewed-by: Cary Clark <caryclark@google.com>
This fix is slightly interesting; if the final
close of the contour degenerates into a zero-length
line, remove the previous line from the generated
contour.
TBR=reed@google.com
BUG=skia:5822
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=3004
Change-Id: Id668d13ccf6aad9bc81d78588fc77437527a0b7b
Reviewed-on: https://skia-review.googlesource.com/3004
Reviewed-by: Cary Clark <caryclark@google.com>
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=2237223002TBR=reed@google.com
BUG=skia:5131
Review-Url: https://codereview.chromium.org/2237223002
This removes the notion of keeping track of every different t value
that resolves to the same or a similar point. Other fixes make
this concept unnecessary, and removing it simplifies the code.
This removes an allocation, and speeds up paths with many
overlapping curves.
As a bonus, four fuzzer tests that failed before now succeed.
TBR=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2275703003
Review-Url: https://codereview.chromium.org/2275703003
Fix another fuzzer bug.
Some PathOps asserts only make sense if the incoming data is
well-behaved. Well-behaved tests set debugging state to
trigger these additional asserts.
Formalize this by creating macros similar to SkASSERT that
check to see if the assert should be skipped.
TBR=reed@google.com
BUG=629962
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2169863002
Review-Url: https://codereview.chromium.org/2169863002
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
