This separates the existing convexity logic into
two passes. The first pass detects concavity by
counting the changes in direction.
The second pass computes the cross product to
see that all angles bend in the same direction, and
computes the dot product to see if the angle
doubles back on itself.
The second pass treats axis-aligned vectors
separately, and computes the dot and cross products
by comparing point values; it does not use arithmetic
to determine convexity, so it works with all finite
values.
A compile time switch enables returning concave
for co-linear diagonal points:
If successive points are not axis-aligned, and
those points are co-linear along a diagonal;
the path is treated as concave. This is conservative
but avoids paths that change convexity when the
are translated or scaled, since transforming the
path may cause the midpoint to shift to either
side of a line formed by the endpoints.
The compile time switch is set so that co-linear
diagonal points do not affect convexity. Note that
this permits shapes formerly considered concave, such
as stroked lines with round caps, to become convex;
this accounts for many of the GM differences.
A path may double back on itself and be convex;
for instance, a path containing a single line.
Path may have multiple initial moveTo verbs, or
trailing moveTo verbs, and still evaluate as convex.
A separate entry point, SkPathPriv::IsConvex()
allows passing an array of points instead of a path.
A legacy define has been checked into Chrome to
use the old code until layout tests have been
rebaselined.
R=reed@google.com,bsalomon@google.com
Bug:899689
Change-Id: I392bbe04836ffb19666ad92ab2a2404c56543019
Reviewed-on: https://skia-review.googlesource.com/c/173427
Reviewed-by: Mike Reed <reed@google.com>
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Cary Clark <caryclark@skia.org>
When repeatedly insetting rings we can wind up with bisector vectors
that correspond to a slightly concave ring. This would cause the first
intersection when computing the next ring's inset depth to be outside
the current ring. Instead skip adjacent bisectors that intersect outside
the ring during the search.
Change-Id: I3efab5a9f44966888cfa86715876b7b177950732
Reviewed-on: https://skia-review.googlesource.com/151827
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
We weren't checking whether the new point in lineTo was backtracking or not.
Also:
Replace distance-to-line check with triangle area check. The previous check
was asymmetric. Given point sequence (a, b, c) it might make a different
decision than when given (c, b, a).
Compute normals late since we don't use them to detect colinear edges
anymore.
Rename SkPointPriv::SetOrhog -> SkPointPriv::MakeOrthog and return
computed value rather than take SkPoint* dst.
Bug: chromium:869172
Change-Id: I8da53edf1a2e6098f4199da57368ebb644866e4c
Reviewed-on: https://skia-review.googlesource.com/150682
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Use this to fill concave shadows.
Bug: skia:7971
Change-Id: I63dc1ed845f9fa3fcd86f1ad13b03da23cae0313
Reviewed-on: https://skia-review.googlesource.com/135200
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Performs inset and outset operations on simple polygons and returns
a simple polygon, if possible.
Bug: skia:
Change-Id: I6d468174ad70b5279b736c532e19cbb84ff9f955
Reviewed-on: https://skia-review.googlesource.com/116483
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Prep for adding new offset routines.
Change-Id: I261c22d9998e5ae4567b697c5f20a31f20777ac1
Reviewed-on: https://skia-review.googlesource.com/116800
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
This class is already just an alias for std::unique_ptr<T[]>, so replace
all uses with that and delete the class.
CQ_INCLUDE_TRYBOTS=master.client.skia:Test-Ubuntu-Clang-GCE-CPU-AVX2-x86_64-Debug-ASAN-Trybot,Test-Ubuntu-Clang-Golo-GPU-GT610-x86_64-Debug-ASAN-Trybot
Change-Id: I40668d398356a22da071ee791666c7f728b59266
Reviewed-on: https://skia-review.googlesource.com/4362
Reviewed-by: Mike Reed <reed@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>
'static const' means, there must be at most one of these, and initialize it at
compile time if possible or runtime if necessary. This leads to unexpected
code execution, and TSAN* will complain about races on the guard variables.
Generally 'constexpr' or 'const' are better choices. Neither can cause races:
they're either intialized at compile time (constexpr) or intialized each time
independently (const).
This CL prefers constexpr where possible, and uses const where not. It even
prefers constexpr over const where they don't make a difference... I want to have
lots of examples of constexpr for people to see and mimic.
The scoped-to-class static has nothing to do with any of this, and is not changed.
* Not yet on the bots, which use an older TSAN.
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2300623005
Review-Url: https://codereview.chromium.org/2300623005
This seems to work well for miter and bevel joins with the resulting stroke and fill path remaining convex. There seems to be an issue with round joins where the outer generated shell is usually not convex. Without this CL the resulting stroke & filled paths are always concave.
Perf-wise (on Windows):
convex-lineonly-paths-stroke-and-fill bench
(in ms) w/o w/CL %decrease
8888 2.88 2.01 30.2
gpu 4.4 1.38 68.6
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2275243003
Review-Url: https://codereview.chromium.org/2275243003
- input param to addFoo (e.g. addRect), where only CW or CCW are valid)
- output param from computing functions, that sometimes return kUnknown
This CL's intent is to split these into distinct enums/features:
- Direction (public) loses kUnknown, and is only used for input
- FirstDirection (private) is used for computing the first direction we see when analyzing a contour
BUG=skia:
Review URL: https://codereview.chromium.org/1176953002
