| |
| /* |
| * Copyright 2011 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| // Unit tests for src/core/SkPoint.cpp and its header |
| |
| #include "SkPoint.h" |
| #include "SkRect.h" |
| #include "Test.h" |
| |
| static void test_casts(skiatest::Reporter* reporter) { |
| SkPoint p = { 0, 0 }; |
| SkRect r = { 0, 0, 0, 0 }; |
| |
| const SkScalar* pPtr = SkTCast<const SkScalar*>(&p); |
| const SkScalar* rPtr = SkTCast<const SkScalar*>(&r); |
| |
| REPORTER_ASSERT(reporter, p.asScalars() == pPtr); |
| REPORTER_ASSERT(reporter, r.asScalars() == rPtr); |
| } |
| |
| // Tests SkPoint::Normalize() for this (x,y) |
| static void test_Normalize(skiatest::Reporter* reporter, |
| SkScalar x, SkScalar y) { |
| SkPoint point; |
| point.set(x, y); |
| SkScalar oldLength = point.length(); |
| SkScalar returned = SkPoint::Normalize(&point); |
| SkScalar newLength = point.length(); |
| REPORTER_ASSERT(reporter, SkScalarNearlyEqual(returned, oldLength)); |
| REPORTER_ASSERT(reporter, SkScalarNearlyEqual(newLength, SK_Scalar1)); |
| } |
| |
| // Tests that SkPoint::length() and SkPoint::Length() both return |
| // approximately expectedLength for this (x,y). |
| static void test_length(skiatest::Reporter* reporter, SkScalar x, SkScalar y, |
| SkScalar expectedLength) { |
| SkPoint point; |
| point.set(x, y); |
| SkScalar s1 = point.length(); |
| SkScalar s2 = SkPoint::Length(x, y); |
| //The following should be exactly the same, but need not be. |
| //See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=323 |
| REPORTER_ASSERT(reporter, SkScalarNearlyEqual(s1, s2)); |
| REPORTER_ASSERT(reporter, SkScalarNearlyEqual(s1, expectedLength)); |
| |
| test_Normalize(reporter, x, y); |
| } |
| |
| // Ugh. Windows compiler can dive into other .cpp files, and sometimes |
| // notices that I will generate an overflow... which is exactly the point |
| // of this test! |
| // |
| // To avoid this warning, I need to convince the compiler that I might not |
| // use that big value, hence this hacky helper function: reporter is |
| // ALWAYS non-null. (shhhhhh, don't tell the compiler that). |
| template <typename T> T get_value(skiatest::Reporter* reporter, T value) { |
| return reporter ? value : 0; |
| } |
| |
| // On linux gcc, 32bit, we are seeing the compiler propagate up the value |
| // of SkPoint::length() as a double (which we use sometimes to avoid overflow |
| // during the computation), even though the signature says float (SkScalar). |
| // |
| // force_as_float is meant to capture our latest technique (horrible as |
| // it is) to force the value to be a float, so we can test whether it was |
| // finite or not. |
| static float force_as_float(skiatest::Reporter* reporter, float value) { |
| uint32_t storage; |
| memcpy(&storage, &value, 4); |
| // even the pair of memcpy calls are not sufficient, since those seem to |
| // be no-op'd, so we add a runtime tests (just like get_value) to force |
| // the compiler to give us an actual float. |
| if (NULL == reporter) { |
| storage = ~storage; |
| } |
| memcpy(&value, &storage, 4); |
| return value; |
| } |
| |
| // test that we handle very large values correctly. i.e. that we can |
| // successfully normalize something whose mag overflows a float. |
| static void test_overflow(skiatest::Reporter* reporter) { |
| SkScalar bigFloat = get_value(reporter, SkFloatToScalar(3.4e38f)); |
| SkPoint pt = { bigFloat, bigFloat }; |
| |
| SkScalar length = pt.length(); |
| length = force_as_float(reporter, length); |
| |
| // expect this to be non-finite, but dump the results if not. |
| if (SkScalarIsFinite(length)) { |
| SkDebugf("length(%g, %g) == %g\n", pt.fX, pt.fY, length); |
| REPORTER_ASSERT(reporter, !SkScalarIsFinite(length)); |
| } |
| |
| // this should succeed, even though we can't represent length |
| REPORTER_ASSERT(reporter, pt.setLength(SK_Scalar1)); |
| |
| // now that pt is normalized, we check its length |
| length = pt.length(); |
| REPORTER_ASSERT(reporter, SkScalarNearlyEqual(length, SK_Scalar1)); |
| } |
| |
| // test that we handle very small values correctly. i.e. that we can |
| // report failure if we try to normalize them. |
| static void test_underflow(skiatest::Reporter* reporter) { |
| SkPoint pt = { SkFloatToScalar(1.0e-37f), SkFloatToScalar(1.0e-37f) }; |
| SkPoint copy = pt; |
| |
| REPORTER_ASSERT(reporter, 0 == SkPoint::Normalize(&pt)); |
| REPORTER_ASSERT(reporter, pt == copy); // pt is unchanged |
| |
| REPORTER_ASSERT(reporter, !pt.setLength(SK_Scalar1)); |
| REPORTER_ASSERT(reporter, pt == copy); // pt is unchanged |
| } |
| |
| static void PointTest(skiatest::Reporter* reporter) { |
| test_casts(reporter); |
| |
| static const struct { |
| SkScalar fX; |
| SkScalar fY; |
| SkScalar fLength; |
| } gRec[] = { |
| { SkIntToScalar(3), SkIntToScalar(4), SkIntToScalar(5) }, |
| { SkFloatToScalar(0.6f), SkFloatToScalar(0.8f), SK_Scalar1 }, |
| }; |
| |
| for (size_t i = 0; i < SK_ARRAY_COUNT(gRec); ++i) { |
| test_length(reporter, gRec[i].fX, gRec[i].fY, gRec[i].fLength); |
| } |
| |
| test_underflow(reporter); |
| test_overflow(reporter); |
| } |
| |
| #include "TestClassDef.h" |
| DEFINE_TESTCLASS("Point", PointTestClass, PointTest) |