skia2/tests/PathMeasureTest.cpp
Mike Reed 62ad46b059 fix contour-measure for move-line-move
Use RawIter, so we can dependably peek() (since consumeDegenerates in
Iter() make peeking unreliable), which caused us to think there were two
real contours in the test case.

Bug: oss-fuzz:13013
Change-Id: I0d85f3e6a83cb972c4d801dd9b17f0e388b926d0
Reviewed-on: https://skia-review.googlesource.com/c/192025
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
2019-02-13 17:14:09 +00:00

309 lines
10 KiB
C++

/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkPathMeasure.h"
#include "Test.h"
static void test_small_segment3() {
SkPath path;
const SkPoint pts[] = {
{ 0, 0 },
{ 100000000000.0f, 100000000000.0f }, { 0, 0 }, { 10, 10 },
{ 10, 10 }, { 0, 0 }, { 10, 10 }
};
path.moveTo(pts[0]);
for (size_t i = 1; i < SK_ARRAY_COUNT(pts); i += 3) {
path.cubicTo(pts[i], pts[i + 1], pts[i + 2]);
}
SkPathMeasure meas(path, false);
meas.getLength();
}
static void test_small_segment2() {
SkPath path;
const SkPoint pts[] = {
{ 0, 0 },
{ 100000000000.0f, 100000000000.0f }, { 0, 0 },
{ 10, 10 }, { 0, 0 },
};
path.moveTo(pts[0]);
for (size_t i = 1; i < SK_ARRAY_COUNT(pts); i += 2) {
path.quadTo(pts[i], pts[i + 1]);
}
SkPathMeasure meas(path, false);
meas.getLength();
}
static void test_small_segment() {
SkPath path;
const SkPoint pts[] = {
{ 100000, 100000},
// big jump between these points, makes a big segment
{ 1.0005f, 0.9999f },
// tiny (non-zero) jump between these points
{ SK_Scalar1, SK_Scalar1 },
};
path.moveTo(pts[0]);
for (size_t i = 1; i < SK_ARRAY_COUNT(pts); ++i) {
path.lineTo(pts[i]);
}
SkPathMeasure meas(path, false);
/* this would assert (before a fix) because we added a segment with
the same length as the prev segment, due to the follow (bad) pattern
d = distance(pts[0], pts[1]);
distance += d;
seg->fDistance = distance;
SkASSERT(d > 0); // TRUE
SkASSERT(seg->fDistance > prevSeg->fDistance); // FALSE
This 2nd assert failes because (distance += d) didn't affect distance
because distance >>> d.
*/
meas.getLength();
}
DEF_TEST(PathMeasure, reporter) {
SkPath path;
path.moveTo(0, 0);
path.lineTo(SK_Scalar1, 0);
path.lineTo(SK_Scalar1, SK_Scalar1);
path.lineTo(0, SK_Scalar1);
SkPathMeasure meas(path, true);
SkScalar length = meas.getLength();
SkASSERT(length == SK_Scalar1*4);
path.reset();
path.moveTo(0, 0);
path.lineTo(SK_Scalar1*3, SK_Scalar1*4);
meas.setPath(&path, false);
length = meas.getLength();
REPORTER_ASSERT(reporter, length == SK_Scalar1*5);
path.reset();
path.addCircle(0, 0, SK_Scalar1);
meas.setPath(&path, true);
length = meas.getLength();
// SkDebugf("circle arc-length = %g\n", length);
// Test the behavior following a close not followed by a move.
path.reset();
path.lineTo(SK_Scalar1, 0);
path.lineTo(SK_Scalar1, SK_Scalar1);
path.lineTo(0, SK_Scalar1);
path.close();
path.lineTo(-SK_Scalar1, 0);
meas.setPath(&path, false);
length = meas.getLength();
REPORTER_ASSERT(reporter, length == SK_Scalar1 * 4);
meas.nextContour();
length = meas.getLength();
REPORTER_ASSERT(reporter, length == SK_Scalar1);
SkPoint position;
SkVector tangent;
REPORTER_ASSERT(reporter, meas.getPosTan(SK_ScalarHalf, &position, &tangent));
REPORTER_ASSERT(reporter,
SkScalarNearlyEqual(position.fX,
-SK_ScalarHalf,
0.0001f));
REPORTER_ASSERT(reporter, position.fY == 0);
REPORTER_ASSERT(reporter, tangent.fX == -SK_Scalar1);
REPORTER_ASSERT(reporter, tangent.fY == 0);
// Test degenerate paths
path.reset();
path.moveTo(0, 0);
path.lineTo(0, 0);
path.lineTo(SK_Scalar1, 0);
path.quadTo(SK_Scalar1, 0, SK_Scalar1, 0);
path.quadTo(SK_Scalar1, SK_Scalar1, SK_Scalar1, SK_Scalar1 * 2);
path.cubicTo(SK_Scalar1, SK_Scalar1 * 2,
SK_Scalar1, SK_Scalar1 * 2,
SK_Scalar1, SK_Scalar1 * 2);
path.cubicTo(SK_Scalar1*2, SK_Scalar1 * 2,
SK_Scalar1*3, SK_Scalar1 * 2,
SK_Scalar1*4, SK_Scalar1 * 2);
meas.setPath(&path, false);
length = meas.getLength();
REPORTER_ASSERT(reporter, length == SK_Scalar1 * 6);
REPORTER_ASSERT(reporter, meas.getPosTan(SK_ScalarHalf, &position, &tangent));
REPORTER_ASSERT(reporter,
SkScalarNearlyEqual(position.fX,
SK_ScalarHalf,
0.0001f));
REPORTER_ASSERT(reporter, position.fY == 0);
REPORTER_ASSERT(reporter, tangent.fX == SK_Scalar1);
REPORTER_ASSERT(reporter, tangent.fY == 0);
REPORTER_ASSERT(reporter, meas.getPosTan(2.5f, &position, &tangent));
REPORTER_ASSERT(reporter,
SkScalarNearlyEqual(position.fX, SK_Scalar1, 0.0001f));
REPORTER_ASSERT(reporter,
SkScalarNearlyEqual(position.fY, 1.5f));
REPORTER_ASSERT(reporter, tangent.fX == 0);
REPORTER_ASSERT(reporter, tangent.fY == SK_Scalar1);
REPORTER_ASSERT(reporter, meas.getPosTan(4.5f, &position, &tangent));
REPORTER_ASSERT(reporter,
SkScalarNearlyEqual(position.fX,
2.5f,
0.0001f));
REPORTER_ASSERT(reporter,
SkScalarNearlyEqual(position.fY,
2.0f,
0.0001f));
REPORTER_ASSERT(reporter, tangent.fX == SK_Scalar1);
REPORTER_ASSERT(reporter, tangent.fY == 0);
path.reset();
path.moveTo(0, 0);
path.lineTo(SK_Scalar1, 0);
path.moveTo(SK_Scalar1, SK_Scalar1);
path.moveTo(SK_Scalar1 * 2, SK_Scalar1 * 2);
path.lineTo(SK_Scalar1, SK_Scalar1 * 2);
meas.setPath(&path, false);
length = meas.getLength();
REPORTER_ASSERT(reporter, length == SK_Scalar1);
REPORTER_ASSERT(reporter, meas.getPosTan(SK_ScalarHalf, &position, &tangent));
REPORTER_ASSERT(reporter,
SkScalarNearlyEqual(position.fX,
SK_ScalarHalf,
0.0001f));
REPORTER_ASSERT(reporter, position.fY == 0);
REPORTER_ASSERT(reporter, tangent.fX == SK_Scalar1);
REPORTER_ASSERT(reporter, tangent.fY == 0);
meas.nextContour();
length = meas.getLength();
REPORTER_ASSERT(reporter, length == SK_Scalar1);
REPORTER_ASSERT(reporter, meas.getPosTan(SK_ScalarHalf, &position, &tangent));
REPORTER_ASSERT(reporter,
SkScalarNearlyEqual(position.fX,
1.5f,
0.0001f));
REPORTER_ASSERT(reporter,
SkScalarNearlyEqual(position.fY,
2.0f,
0.0001f));
REPORTER_ASSERT(reporter, tangent.fX == -SK_Scalar1);
REPORTER_ASSERT(reporter, tangent.fY == 0);
test_small_segment();
test_small_segment2();
test_small_segment3();
}
DEF_TEST(PathMeasureConic, reporter) {
SkPoint stdP, hiP, pts[] = {{0,0}, {100,0}, {100,0}};
SkPath p;
p.moveTo(0, 0);
p.conicTo(pts[1], pts[2], 1);
SkPathMeasure stdm(p, false);
REPORTER_ASSERT(reporter, stdm.getPosTan(20, &stdP, nullptr));
p.reset();
p.moveTo(0, 0);
p.conicTo(pts[1], pts[2], 10);
stdm.setPath(&p, false);
REPORTER_ASSERT(reporter, stdm.getPosTan(20, &hiP, nullptr));
REPORTER_ASSERT(reporter, 19.5f < stdP.fX && stdP.fX < 20.5f);
REPORTER_ASSERT(reporter, 19.5f < hiP.fX && hiP.fX < 20.5f);
}
// Regression test for b/26425223
DEF_TEST(PathMeasure_nextctr, reporter) {
SkPath path;
path.moveTo(0, 0); path.lineTo(100, 0);
SkPathMeasure meas(path, false);
// only expect 1 contour, even if we didn't explicitly call getLength() ourselves
REPORTER_ASSERT(reporter, !meas.nextContour());
}
#include "SkContourMeasure.h"
static void test_90_degrees(sk_sp<SkContourMeasure> cm, SkScalar radius,
skiatest::Reporter* reporter) {
SkPoint pos;
SkVector tan;
SkScalar distance = cm->length() / 4;
bool success = cm->getPosTan(distance, &pos, &tan);
REPORTER_ASSERT(reporter, success);
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(pos.fX, 0));
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(pos.fY, radius));
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(tan.fX, -1));
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(tan.fY, 0));
}
static void test_empty_contours(skiatest::Reporter* reporter) {
SkPath path;
path.moveTo(0, 0).lineTo(100, 100).lineTo(200, 100);
path.moveTo(2, 2).moveTo(3, 3); // zero-length(s)
path.moveTo(4, 4).close().close().close(); // zero-length
path.moveTo(5, 5).lineTo(5, 5); // zero-length
path.moveTo(5, 5).lineTo(5, 5).close(); // zero-length
path.moveTo(5, 5).lineTo(5, 5).close().close(); // zero-length
path.moveTo(6, 6).lineTo(7, 7);
path.moveTo(10, 10); // zero-length
SkContourMeasureIter fact(path, false);
// given the above construction, we expect only 2 contours (the rest are "empty")
REPORTER_ASSERT(reporter, fact.next());
REPORTER_ASSERT(reporter, fact.next());
REPORTER_ASSERT(reporter, !fact.next());
}
static void test_MLM_contours(skiatest::Reporter* reporter) {
SkPath path;
// This odd sequence (with a trailing moveTo) used to return a 2nd contour, which is
// wrong, since the contract for a measure is to only return non-zero length contours.
path.moveTo(10, 10).lineTo(20, 20).moveTo(30, 30);
for (bool forceClosed : {false, true}) {
SkContourMeasureIter fact(path, forceClosed);
REPORTER_ASSERT(reporter, fact.next());
REPORTER_ASSERT(reporter, !fact.next());
}
}
DEF_TEST(contour_measure, reporter) {
SkPath path;
path.addCircle(0, 0, 100);
path.addCircle(0, 0, 10);
SkContourMeasureIter fact(path, false);
path.reset(); // we should not need the path avert we created the factory
auto cm0 = fact.next();
auto cm1 = fact.next();
REPORTER_ASSERT(reporter, cm0->isClosed());
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(cm0->length(), 200 * SK_ScalarPI, 1.5f));
test_90_degrees(cm0, 100, reporter);
REPORTER_ASSERT(reporter, cm1->isClosed());
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(cm1->length(), 20 * SK_ScalarPI, 0.5f));
test_90_degrees(cm1, 10, reporter);
auto cm2 = fact.next();
REPORTER_ASSERT(reporter, !cm2);
test_empty_contours(reporter);
test_MLM_contours(reporter);
}