Extreme implicit quartic equations solve to roots that are different
enough that they appear to have failed. In this case, fall back on
binary searching to find an intersection.
Relax the condition when this happens; don't give up just because the
computed implicit root points aren't remotely the same.
TBR=reed
BUG=skia:2808
Author: caryclark@google.com
Review URL: https://codereview.chromium.org/456383003
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
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
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
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
Modify line intersections to first
- match exact ends
- compute intersections
- match near ends
where the exact ends are preferred, then near matches, then
computed matches. This pulls matches towards existing end points
when possible, and keeps intersection distances consistent with
different line/line line/quad and line/cubic computations.
BUG=
Review URL: https://codereview.chromium.org/19183003
git-svn-id: http://skia.googlecode.com/svn/trunk@10073 2bbb7eff-a529-9590-31e7-b0007b416f81
This is a major change resulting from a minor
tweak. In the old code, the intersection point
of two curves was shared between them, but the
intersection points and end points of sorted edges was
computed directly from the intersection T value.
In this CL, both intersection points and sorted points
are the same, and intermediate control points are computed
to preserve their slope.
The sort itself has been completely rewritten to be more
robust and remove 'magic' checks, conditions that empirically
worked but couldn't be rationalized.
This CL was triggered by errors generated computing the clips
of SKP files. At this point, all 73M standard tests work and
at least the first troublesome SKPs work.
Review URL: https://codereview.chromium.org/15338003
git-svn-id: http://skia.googlecode.com/svn/trunk@9432 2bbb7eff-a529-9590-31e7-b0007b416f81
fix bugs in tests on 32 bit release
Most changes revolve around pinning computed t values
very close to zero and one.
git-svn-id: http://skia.googlecode.com/svn/trunk@8745 2bbb7eff-a529-9590-31e7-b0007b416f81
Try to fix the 32 bit build by making some math
decisions more robust.
Rewrite the cubic intersection special case that
detects if only end points are shared.
Rewrite the angle sort setup that computes whether
a cubic bends to the left or right.
git-svn-id: http://skia.googlecode.com/svn/trunk@8726 2bbb7eff-a529-9590-31e7-b0007b416f81
standardize tests
use SK_ARRAY_COUNT everywhere
debug why x87 differs from SIMD 64
various platform specific fixes
git-svn-id: http://skia.googlecode.com/svn/trunk@8689 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
