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
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
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
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
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
PathOps tests internal routines direcctly. Check to make sure that
test points, lines, quads, curves, triangles, and bounds read from
arrays are valid (i.e., don't contain NaN) before calling the
test function.
Repurpose the test flags.
- make 'v' verbose test region output against path output
- make 'z' single threaded (before it made it multithreaded)
The latter change speeds up tests run by the buildbot by 2x to 3x.
BUG=
Review URL: https://codereview.chromium.org/19374003
git-svn-id: http://skia.googlecode.com/svn/trunk@10107 2bbb7eff-a529-9590-31e7-b0007b416f81
Replace SkTDArray with SkTArray and use SkSTArray when
the probable array size is known.
In a couple of places (spans, chases) the arrays are
constructed using insert() so SkTArrays can't be used for
now.
Also, add an optimization to cubic subdivide if either end
is zero or one.
BUG=
Review URL: https://codereview.chromium.org/16951017
git-svn-id: http://skia.googlecode.com/svn/trunk@9635 2bbb7eff-a529-9590-31e7-b0007b416f81
This CL depends on
https://codereview.chromium.org/12880016/
"Add intersections for path ops"
Given a path, iterate through its contour, and
construct an array of segments containing its curves.
Intersect each curve with every other curve, and for
cubics, with itself.
Given the set of intersections, find one with the
smallest y and sort the curves eminating from the
intersection. Assign each curve a winding value.
Operate on the curves, keeping and discarding them
according to the current operation and the sum of
the winding values.
Assemble the kept curves into an output path.
Review URL: https://codereview.chromium.org/13094010
git-svn-id: http://skia.googlecode.com/svn/trunk@8553 2bbb7eff-a529-9590-31e7-b0007b416f81
