diff options
| -rw-r--r-- | src/core/SkGeometry.cpp | 26 | ||||
| -rw-r--r-- | tests/GeometryTest.cpp | 18 |
2 files changed, 32 insertions, 12 deletions
diff --git a/src/core/SkGeometry.cpp b/src/core/SkGeometry.cpp index 3c9e9f90f0..57ce2fdb10 100644 --- a/src/core/SkGeometry.cpp +++ b/src/core/SkGeometry.cpp @@ -448,18 +448,20 @@ int SkChopQuadAtMaxCurvature(const SkPoint src[3], SkPoint dst[5]) } } -void SkConvertQuadToCubic(const SkPoint src[3], SkPoint dst[4]) -{ - SkScalar two = SkIntToScalar(2); - SkScalar one_third = SkScalarDiv(SK_Scalar1, SkIntToScalar(3)); - dst[0].set(src[0].fX, src[0].fY); - dst[1].set( - SkScalarMul(SkScalarMulAdd(src[1].fX, two, src[0].fX), one_third), - SkScalarMul(SkScalarMulAdd(src[1].fY, two, src[0].fY), one_third)); - dst[2].set( - SkScalarMul(SkScalarMulAdd(src[1].fX, two, src[2].fX), one_third), - SkScalarMul(SkScalarMulAdd(src[1].fY, two, src[2].fY), one_third)); - dst[3].set(src[2].fX, src[2].fY); +#ifdef SK_SCALAR_IS_FLOAT + #define SK_ScalarTwoThirds (0.666666666f) +#else + #define SK_ScalarTwoThirds ((SkFixed)(43691)) +#endif + +void SkConvertQuadToCubic(const SkPoint src[3], SkPoint dst[4]) { + const SkScalar scale = SK_ScalarTwoThirds; + dst[0] = src[0]; + dst[1].set(src[0].fX + SkScalarMul(src[1].fX - src[0].fX, scale), + src[0].fY + SkScalarMul(src[1].fY - src[0].fY, scale)); + dst[2].set(src[2].fX + SkScalarMul(src[1].fX - src[2].fX, scale), + src[2].fY + SkScalarMul(src[1].fY - src[2].fY, scale)); + dst[3] = src[2]; } //////////////////////////////////////////////////////////////////////////////////////// diff --git a/tests/GeometryTest.cpp b/tests/GeometryTest.cpp index 5b05952c84..146528897d 100644 --- a/tests/GeometryTest.cpp +++ b/tests/GeometryTest.cpp @@ -1,6 +1,10 @@ #include "Test.h" #include "SkGeometry.h" +static bool nearly_equal(const SkPoint& a, const SkPoint& b) { + return SkScalarNearlyEqual(a.fX, b.fX) && SkScalarNearlyEqual(a.fY, b.fY); +} + static void TestGeometry(skiatest::Reporter* reporter) { SkPoint pts[3], dst[5]; @@ -10,6 +14,20 @@ static void TestGeometry(skiatest::Reporter* reporter) { int count = SkChopQuadAtMaxCurvature(pts, dst); REPORTER_ASSERT(reporter, count == 1 || count == 2); + + pts[0].set(0, 0); + pts[1].set(SkIntToScalar(3), 0); + pts[2].set(SkIntToScalar(3), SkIntToScalar(3)); + SkConvertQuadToCubic(pts, dst); + const SkPoint cubic[] = { + 0, 0, + SkIntToScalar(2), 0, + SkIntToScalar(3), SkIntToScalar(1), + SkIntToScalar(3), SkIntToScalar(3) + }; + for (int i = 0; i < 4; ++i) { + REPORTER_ASSERT(reporter, nearly_equal(cubic[i], dst[i])); + } } #include "TestClassDef.h" |