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
The following are currently unused in Android, Google3, Chromium, and Mozilla:
- SkEvent
- SkTime::GetMSecs
- SK_TIME_FACTOR (also unused in Skia)
- SkAutoTime
I left uses of SkMSec more-or-less intact for SkEvent, SkAnimator, and SkInterpolator. SkInterpolator is used in Chromium, so I did not want to change the API. The views/ and animator/ code is crufty, so it didn't seem worthwhile to refactor it. Instead, I added SkEvent::GetMSecsSinceStartup, which is likely to be adequate for use in SampleApp.
I also left SkMSec where it is used to measure a duration rather than a timestamp. With the exception of SkMovie, which is used in Android, all of the uses appear to measure the execution time of a piece of code, which I would hope does not exceed 2^31 milliseconds.
Added skiatest::Timer to support a common idiom in tests where we want to measure the wallclock time in integer milliseconds. (Not used in tests/PathOpsSkpClipTest.cpp because it redefines things in Test.h.)
Removed tabs in tests/StrokerTest.cpp.
BUG=skia:4632
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1811613004
Review URL: https://codereview.chromium.org/1811613004
Remove SkLCGRandom. We already decided the new one was better, which is
why we wrote the new SkRandom.
Convert GMs that were using SkLCGRandom to use the improved SkRandom.
Motivated by the fact that these GMs draw differently on some runs. We
believe this to be a result of using the old SkLCGRandom.
Add each of the tests that were using SkLCGRandom to ignore-tests.txt,
since we expect they'll draw differently using SkRandom.
Move a trimmed down version of SkLCGRandom into SkDiscretePathEffect.
In order to preserve the old behavior, trim down SkLCGRandom to only
the methods used by SkDiscretePathEffect, and hide it in
SkDiscretePathEffect's cpp file.
BUG=skia:3241
Review URL: https://codereview.chromium.org/805963002
Draw thick-stroked Beziers by computing the outset quadratic, measuring the error, and subdividing until the error is within a predetermined limit.
To try this CL out, change src/core/SkStroke.h:18 to
#define QUAD_STROKE_APPROXIMATION 1
or from the command line: CPPFLAGS="-D QUAD_STROKE_APPROXIMATION=1" ./gyp_skia
Here's what's in this CL:
bench/BezierBench.cpp : a microbench for examining where the time is going
gm/beziers.cpp : random Beziers with various thicknesses
gm/smallarc.cpp : a distillation of bug skia:2769
samplecode/SampleRotateCircles.cpp : controls added for error, limit, width
src/core/SkStroke.cpp : the new stroke implementation (disabled)
tests/StrokerTest.cpp : a stroke torture test that checks normal and extreme values
The new stroke algorithm has a tweakable parameter:
stroker.setError(1); (SkStrokeRec.cpp:112)
The stroke error is the allowable gap between the midpoint of the stroke quadratic and the center Bezier. As the projection from the quadratic approaches the endpoints, the error is decreased proportionally so that it is always inside the quadratic curve.
An overview of how this works:
- For a given T range of a Bezier, compute the perpendiculars and find the points outset and inset for some radius.
- Construct tangents for the quadratic stroke.
- If the tangent don't intersect between them (may happen with cubics), subdivide.
- If the quadratic stroke end points are close (again, may happen with cubics), draw a line between them.
- Compute the quadratic formed by the intersecting tangents.
- If the midpoint of the quadratic is close to the midpoint of the Bezier perpendicular, return the quadratic.
- If the end of the stroke at the Bezier midpoint doesn't intersect the quad's bounds, subdivide.
- Find where the Bezier midpoint ray intersects the quadratic.
- If the intersection is too close to the quad's endpoints, subdivide.
- If the error is large proportional to the intersection's distance to the quad's endpoints, subdivide.
BUG=skia:723,skia:2769
Review URL: https://codereview.chromium.org/558163005
