DEF_TEST(PathOpsAngleFindQuadEpsilon, reporter) { if (gDisableAngleTests) { return; } SkRandom ran; int maxEpsilon = 0; double maxAngle = 0; for (int index = 0; index < 100000; ++index) { SkDLine line = {{{0, 0}, {ran.nextRangeF(0.0001f, 1000), ran.nextRangeF(0.0001f, 1000)}}}; float t = ran.nextRangeF(0.0001f, 1); SkDPoint dPt = line.ptAtT(t); float t2 = ran.nextRangeF(0.0001f, 1); SkDPoint qPt = line.ptAtT(t2); float t3 = ran.nextRangeF(0.0001f, 1); SkDPoint qPt2 = line.ptAtT(t3); qPt.fX += qPt2.fY; qPt.fY -= qPt2.fX; QuadPts q = {{line[0], dPt, qPt}}; SkDQuad quad; quad.debugSet(q.fPts); // binary search for maximum movement of quad[1] towards test that still has 1 intersection double moveT = 0.5f; double deltaT = moveT / 2; SkDPoint last; do { last = quad[1]; quad[1].fX = dPt.fX - line[1].fY * moveT; quad[1].fY = dPt.fY + line[1].fX * moveT; SkIntersections i; i.intersect(quad, line); REPORTER_ASSERT(reporter, i.used() > 0); if (i.used() == 1) { moveT += deltaT; } else { moveT -= deltaT; } deltaT /= 2; } while (last.asSkPoint() != quad[1].asSkPoint()); float p1 = SkDoubleToScalar(line[1].fX * last.fY); float p2 = SkDoubleToScalar(line[1].fY * last.fX); int p1Bits = SkFloatAs2sCompliment(p1); int p2Bits = SkFloatAs2sCompliment(p2); int epsilon = SkTAbs(p1Bits - p2Bits); if (maxEpsilon < epsilon) { SkDebugf("line={{0, 0}, {%1.7g, %1.7g}} t=%1.7g/%1.7g/%1.7g moveT=%1.7g" " pt={%1.7g, %1.7g} epsilon=%d\n", line[1].fX, line[1].fY, t, t2, t3, moveT, last.fX, last.fY, epsilon); maxEpsilon = epsilon; } double a1 = atan2(line[1].fY, line[1].fX); double a2 = atan2(last.fY, last.fX); double angle = fabs(a1 - a2); if (maxAngle < angle) { SkDebugf("line={{0, 0}, {%1.7g, %1.7g}} t=%1.7g/%1.7g/%1.7g moveT=%1.7g" " pt={%1.7g, %1.7g} angle=%1.7g\n", line[1].fX, line[1].fY, t, t2, t3, moveT, last.fX, last.fY, angle); maxAngle = angle; } } }
DEF_TEST(PathOpsAngleFindCrossEpsilon, reporter) { if (gDisableAngleTests) { return; } SkRandom ran; int maxEpsilon = 0; for (int index = 0; index < 10000000; ++index) { SkDLine line = {{{0, 0}, {ran.nextRangeF(0.0001f, 1000), ran.nextRangeF(0.0001f, 1000)}}}; for (int inner = 0; inner < 10; ++inner) { float t = ran.nextRangeF(0.0001f, 1); SkDPoint dPt = line.ptAtT(t); SkPoint pt = dPt.asSkPoint(); float xs[3] = { prev(pt.fX), pt.fX, next(pt.fX) }; float ys[3] = { prev(pt.fY), pt.fY, next(pt.fY) }; for (int xIdx = 0; xIdx < 3; ++xIdx) { for (int yIdx = 0; yIdx < 3; ++yIdx) { SkPoint test = { xs[xIdx], ys[yIdx] }; float p1 = SkDoubleToScalar(line[1].fX * test.fY); float p2 = SkDoubleToScalar(line[1].fY * test.fX); int p1Bits = SkFloatAs2sCompliment(p1); int p2Bits = SkFloatAs2sCompliment(p2); int epsilon = SkTAbs(p1Bits - p2Bits); if (maxEpsilon < epsilon) { SkDebugf("line={{0, 0}, {%1.7g, %1.7g}} t=%1.7g pt={%1.7g, %1.7g}" " epsilon=%d\n", line[1].fX, line[1].fY, t, test.fX, test.fY, epsilon); maxEpsilon = epsilon; } } } } } }
static bool d_not_equal_ulps(float a, float b, int epsilon) { if (!SkScalarIsFinite(a) || !SkScalarIsFinite(b)) { return false; } int aBits = SkFloatAs2sCompliment(a); int bBits = SkFloatAs2sCompliment(b); // Find the difference in ULPs. return aBits >= bBits + epsilon || bBits >= aBits + epsilon; }
static bool less_or_equal_ulps(float a, float b, int epsilon) { if (!SkScalarIsFinite(a) || !SkScalarIsFinite(b)) { return false; } if (arguments_denormalized(a, b, epsilon)) { return a < b + FLT_EPSILON * epsilon; } int aBits = SkFloatAs2sCompliment(a); int bBits = SkFloatAs2sCompliment(b); // Find the difference in ULPs. return aBits < bBits + epsilon; }
// from http://randomascii.wordpress.com/2012/02/25/comparing-floating-point-numbers-2012-edition/ // FIXME: move to SkFloatBits.h static bool equal_ulps(float a, float b, int epsilon, int depsilon) { if (!SkScalarIsFinite(a) || !SkScalarIsFinite(b)) { return false; } if (arguments_denormalized(a, b, depsilon)) { return true; } int aBits = SkFloatAs2sCompliment(a); int bBits = SkFloatAs2sCompliment(b); // Find the difference in ULPs. return aBits < bBits + epsilon && bBits < aBits + epsilon; }
static float prev(float f) { int fBits = SkFloatAs2sCompliment(f); --fBits; float fNext = Sk2sComplimentAsFloat(fBits); return fNext; }