/* * 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 "Test.h" #include "SkFloatBits.h" #include "SkFloatingPoint.h" #include "SkMathPriv.h" #include "SkPoint.h" #include "SkRandom.h" #include "SkColorPriv.h" static void test_clz(skiatest::Reporter* reporter) { REPORTER_ASSERT(reporter, 32 == SkCLZ(0)); REPORTER_ASSERT(reporter, 31 == SkCLZ(1)); REPORTER_ASSERT(reporter, 1 == SkCLZ(1 << 30)); REPORTER_ASSERT(reporter, 0 == SkCLZ(~0U)); SkRandom rand; for (int i = 0; i < 1000; ++i) { uint32_t mask = rand.nextU(); // need to get some zeros for testing, but in some obscure way so the // compiler won't "see" that, and work-around calling the functions. mask >>= (mask & 31); int intri = SkCLZ(mask); int porta = SkCLZ_portable(mask); REPORTER_ASSERT(reporter, intri == porta); } } /////////////////////////////////////////////////////////////////////////////// static float sk_fsel(float pred, float result_ge, float result_lt) { return pred >= 0 ? result_ge : result_lt; } static float fast_floor(float x) { // float big = sk_fsel(x, 0x1.0p+23, -0x1.0p+23); float big = sk_fsel(x, (float)(1 << 23), -(float)(1 << 23)); return (float)(x + big) - big; } static float std_floor(float x) { return sk_float_floor(x); } static void test_floor_value(skiatest::Reporter* reporter, float value) { float fast = fast_floor(value); float std = std_floor(value); REPORTER_ASSERT(reporter, std == fast); // SkDebugf("value[%1.9f] std[%g] fast[%g] equal[%d]\n", // value, std, fast, std == fast); } static void test_floor(skiatest::Reporter* reporter) { static const float gVals[] = { 0, 1, 1.1f, 1.01f, 1.001f, 1.0001f, 1.00001f, 1.000001f, 1.0000001f }; for (size_t i = 0; i < SK_ARRAY_COUNT(gVals); ++i) { test_floor_value(reporter, gVals[i]); // test_floor_value(reporter, -gVals[i]); } } /////////////////////////////////////////////////////////////////////////////// // test that SkMul16ShiftRound and SkMulDiv255Round return the same result static void test_muldivround(skiatest::Reporter* reporter) { #if 0 // this "complete" test is too slow, so we test a random sampling of it for (int a = 0; a <= 32767; ++a) { for (int b = 0; b <= 32767; ++b) { unsigned prod0 = SkMul16ShiftRound(a, b, 8); unsigned prod1 = SkMulDiv255Round(a, b); SkASSERT(prod0 == prod1); } } #endif SkRandom rand; for (int i = 0; i < 10000; ++i) { unsigned a = rand.nextU() & 0x7FFF; unsigned b = rand.nextU() & 0x7FFF; unsigned prod0 = SkMul16ShiftRound(a, b, 8); unsigned prod1 = SkMulDiv255Round(a, b); REPORTER_ASSERT(reporter, prod0 == prod1); } } static float float_blend(int src, int dst, float unit) { return dst + (src - dst) * unit; } static int blend31(int src, int dst, int a31) { return dst + ((src - dst) * a31 * 2114 >> 16); // return dst + ((src - dst) * a31 * 33 >> 10); } static int blend31_slow(int src, int dst, int a31) { int prod = src * a31 + (31 - a31) * dst + 16; prod = (prod + (prod >> 5)) >> 5; return prod; } static int blend31_round(int src, int dst, int a31) { int prod = (src - dst) * a31 + 16; prod = (prod + (prod >> 5)) >> 5; return dst + prod; } static int blend31_old(int src, int dst, int a31) { a31 += a31 >> 4; return dst + ((src - dst) * a31 >> 5); } // suppress unused code warning static int (*blend_functions[])(int, int, int) = { blend31, blend31_slow, blend31_round, blend31_old }; static void test_blend31() { int failed = 0; int death = 0; if (false) { // avoid bit rot, suppress warning failed = (*blend_functions[0])(0,0,0); } for (int src = 0; src <= 255; src++) { for (int dst = 0; dst <= 255; dst++) { for (int a = 0; a <= 31; a++) { // int r0 = blend31(src, dst, a); // int r0 = blend31_round(src, dst, a); // int r0 = blend31_old(src, dst, a); int r0 = blend31_slow(src, dst, a); float f = float_blend(src, dst, a / 31.f); int r1 = (int)f; int r2 = SkScalarRoundToInt(SkFloatToScalar(f)); if (r0 != r1 && r0 != r2) { printf("src:%d dst:%d a:%d result:%d float:%g\n", src, dst, a, r0, f); failed += 1; } if (r0 > 255) { death += 1; printf("death src:%d dst:%d a:%d result:%d float:%g\n", src, dst, a, r0, f); } } } } SkDebugf("---- failed %d death %d\n", failed, death); } static void test_blend(skiatest::Reporter* reporter) { for (int src = 0; src <= 255; src++) { for (int dst = 0; dst <= 255; dst++) { for (int a = 0; a <= 255; a++) { int r0 = SkAlphaBlend255(src, dst, a); float f1 = float_blend(src, dst, a / 255.f); int r1 = SkScalarRoundToInt(SkFloatToScalar(f1)); if (r0 != r1) { float diff = sk_float_abs(f1 - r1); diff = sk_float_abs(diff - 0.5f); if (diff > (1 / 255.f)) { #ifdef SK_DEBUG SkDebugf("src:%d dst:%d a:%d result:%d float:%g\n", src, dst, a, r0, f1); #endif REPORTER_ASSERT(reporter, false); } } } } } } #if defined(SkLONGLONG) static int symmetric_fixmul(int a, int b) { int sa = SkExtractSign(a); int sb = SkExtractSign(b); a = SkApplySign(a, sa); b = SkApplySign(b, sb); #if 1 int c = (int)(((SkLONGLONG)a * b) >> 16); return SkApplySign(c, sa ^ sb); #else SkLONGLONG ab = (SkLONGLONG)a * b; if (sa ^ sb) { ab = -ab; } return ab >> 16; #endif } #endif static void check_length(skiatest::Reporter* reporter, const SkPoint& p, SkScalar targetLen) { float x = SkScalarToFloat(p.fX); float y = SkScalarToFloat(p.fY); float len = sk_float_sqrt(x*x + y*y); len /= SkScalarToFloat(targetLen); REPORTER_ASSERT(reporter, len > 0.999f && len < 1.001f); } static float nextFloat(SkRandom& rand) { SkFloatIntUnion data; data.fSignBitInt = rand.nextU(); return data.fFloat; } /* returns true if a == b as resulting from (int)x. Since it is undefined what to do if the float exceeds 2^32-1, we check for that explicitly. */ static bool equal_float_native_skia(float x, uint32_t ni, uint32_t si) { if (!(x == x)) { // NAN return ((int32_t)si) == SK_MaxS32 || ((int32_t)si) == SK_MinS32; } // for out of range, C is undefined, but skia always should return NaN32 if (x > SK_MaxS32) { return ((int32_t)si) == SK_MaxS32; } if (x < -SK_MaxS32) { return ((int32_t)si) == SK_MinS32; } return si == ni; } static void assert_float_equal(skiatest::Reporter* reporter, const char op[], float x, uint32_t ni, uint32_t si) { if (!equal_float_native_skia(x, ni, si)) { SkString desc; uint32_t xi = SkFloat2Bits(x); desc.printf("%s float %g bits %x native %x skia %x\n", op, x, xi, ni, si); reporter->reportFailed(desc); } } static void test_float_cast(skiatest::Reporter* reporter, float x) { int ix = (int)x; int iix = SkFloatToIntCast(x); assert_float_equal(reporter, "cast", x, ix, iix); } static void test_float_floor(skiatest::Reporter* reporter, float x) { int ix = (int)floor(x); int iix = SkFloatToIntFloor(x); assert_float_equal(reporter, "floor", x, ix, iix); } static void test_float_round(skiatest::Reporter* reporter, float x) { double xx = x + 0.5; // need intermediate double to avoid temp loss int ix = (int)floor(xx); int iix = SkFloatToIntRound(x); assert_float_equal(reporter, "round", x, ix, iix); } static void test_float_ceil(skiatest::Reporter* reporter, float x) { int ix = (int)ceil(x); int iix = SkFloatToIntCeil(x); assert_float_equal(reporter, "ceil", x, ix, iix); } static void test_float_conversions(skiatest::Reporter* reporter, float x) { test_float_cast(reporter, x); test_float_floor(reporter, x); test_float_round(reporter, x); test_float_ceil(reporter, x); } static void test_int2float(skiatest::Reporter* reporter, int ival) { float x0 = (float)ival; float x1 = SkIntToFloatCast(ival); float x2 = SkIntToFloatCast_NoOverflowCheck(ival); REPORTER_ASSERT(reporter, x0 == x1); REPORTER_ASSERT(reporter, x0 == x2); } static void unittest_fastfloat(skiatest::Reporter* reporter) { SkRandom rand; size_t i; static const float gFloats[] = { 0.f, 1.f, 0.5f, 0.499999f, 0.5000001f, 1.f/3, 0.000000001f, 1000000000.f, // doesn't overflow 0.0000000001f, 10000000000.f // does overflow }; for (i = 0; i < SK_ARRAY_COUNT(gFloats); i++) { test_float_conversions(reporter, gFloats[i]); test_float_conversions(reporter, -gFloats[i]); } for (int outer = 0; outer < 100; outer++) { rand.setSeed(outer); for (i = 0; i < 100000; i++) { float x = nextFloat(rand); test_float_conversions(reporter, x); } test_int2float(reporter, 0); test_int2float(reporter, 1); test_int2float(reporter, -1); for (i = 0; i < 100000; i++) { // for now only test ints that are 24bits or less, since we don't // round (down) large ints the same as IEEE... int ival = rand.nextU() & 0xFFFFFF; test_int2float(reporter, ival); test_int2float(reporter, -ival); } } } #ifdef SK_SCALAR_IS_FLOAT static float make_zero() { return sk_float_sin(0); } #endif static void unittest_isfinite(skiatest::Reporter* reporter) { #ifdef SK_SCALAR_IS_FLOAT float nan = sk_float_asin(2); float inf = 1.0f / make_zero(); float big = 3.40282e+038f; REPORTER_ASSERT(reporter, !SkScalarIsNaN(inf)); REPORTER_ASSERT(reporter, !SkScalarIsNaN(-inf)); REPORTER_ASSERT(reporter, !SkScalarIsFinite(inf)); REPORTER_ASSERT(reporter, !SkScalarIsFinite(-inf)); #else SkFixed nan = SK_FixedNaN; SkFixed big = SK_FixedMax; #endif REPORTER_ASSERT(reporter, SkScalarIsNaN(nan)); REPORTER_ASSERT(reporter, !SkScalarIsNaN(big)); REPORTER_ASSERT(reporter, !SkScalarIsNaN(-big)); REPORTER_ASSERT(reporter, !SkScalarIsNaN(0)); REPORTER_ASSERT(reporter, !SkScalarIsFinite(nan)); REPORTER_ASSERT(reporter, SkScalarIsFinite(big)); REPORTER_ASSERT(reporter, SkScalarIsFinite(-big)); REPORTER_ASSERT(reporter, SkScalarIsFinite(0)); } static void test_muldiv255(skiatest::Reporter* reporter) { for (int a = 0; a <= 255; a++) { for (int b = 0; b <= 255; b++) { int ab = a * b; float s = ab / 255.0f; int round = (int)floorf(s + 0.5f); int trunc = (int)floorf(s); int iround = SkMulDiv255Round(a, b); int itrunc = SkMulDiv255Trunc(a, b); REPORTER_ASSERT(reporter, iround == round); REPORTER_ASSERT(reporter, itrunc == trunc); REPORTER_ASSERT(reporter, itrunc <= iround); REPORTER_ASSERT(reporter, iround <= a); REPORTER_ASSERT(reporter, iround <= b); } } } static void test_muldiv255ceiling(skiatest::Reporter* reporter) { for (int c = 0; c <= 255; c++) { for (int a = 0; a <= 255; a++) { int product = (c * a + 255); int expected_ceiling = (product + (product >> 8)) >> 8; int webkit_ceiling = (c * a + 254) / 255; REPORTER_ASSERT(reporter, expected_ceiling == webkit_ceiling); int skia_ceiling = SkMulDiv255Ceiling(c, a); REPORTER_ASSERT(reporter, skia_ceiling == webkit_ceiling); } } } static void test_copysign(skiatest::Reporter* reporter) { static const int32_t gTriples[] = { // x, y, expected result 0, 0, 0, 0, 1, 0, 0, -1, 0, 1, 0, 1, 1, 1, 1, 1, -1, -1, -1, 0, 1, -1, 1, 1, -1, -1, -1, }; for (size_t i = 0; i < SK_ARRAY_COUNT(gTriples); i += 3) { REPORTER_ASSERT(reporter, SkCopySign32(gTriples[i], gTriples[i+1]) == gTriples[i+2]); float x = (float)gTriples[i]; float y = (float)gTriples[i+1]; float expected = (float)gTriples[i+2]; REPORTER_ASSERT(reporter, sk_float_copysign(x, y) == expected); } SkRandom rand; for (int j = 0; j < 1000; j++) { int ix = rand.nextS(); REPORTER_ASSERT(reporter, SkCopySign32(ix, ix) == ix); REPORTER_ASSERT(reporter, SkCopySign32(ix, -ix) == -ix); REPORTER_ASSERT(reporter, SkCopySign32(-ix, ix) == ix); REPORTER_ASSERT(reporter, SkCopySign32(-ix, -ix) == -ix); SkScalar sx = rand.nextSScalar1(); REPORTER_ASSERT(reporter, SkScalarCopySign(sx, sx) == sx); REPORTER_ASSERT(reporter, SkScalarCopySign(sx, -sx) == -sx); REPORTER_ASSERT(reporter, SkScalarCopySign(-sx, sx) == sx); REPORTER_ASSERT(reporter, SkScalarCopySign(-sx, -sx) == -sx); } } static void TestMath(skiatest::Reporter* reporter) { int i; int32_t x; SkRandom rand; // these should assert #if 0 SkToS8(128); SkToS8(-129); SkToU8(256); SkToU8(-5); SkToS16(32768); SkToS16(-32769); SkToU16(65536); SkToU16(-5); if (sizeof(size_t) > 4) { SkToS32(4*1024*1024); SkToS32(-4*1024*1024); SkToU32(5*1024*1024); SkToU32(-5); } #endif test_muldiv255(reporter); test_muldiv255ceiling(reporter); test_copysign(reporter); { SkScalar x = SK_ScalarNaN; REPORTER_ASSERT(reporter, SkScalarIsNaN(x)); } for (i = 1; i <= 10; i++) { x = SkCubeRootBits(i*i*i, 11); REPORTER_ASSERT(reporter, x == i); } x = SkFixedSqrt(SK_Fixed1); REPORTER_ASSERT(reporter, x == SK_Fixed1); x = SkFixedSqrt(SK_Fixed1/4); REPORTER_ASSERT(reporter, x == SK_Fixed1/2); x = SkFixedSqrt(SK_Fixed1*4); REPORTER_ASSERT(reporter, x == SK_Fixed1*2); x = SkFractSqrt(SK_Fract1); REPORTER_ASSERT(reporter, x == SK_Fract1); x = SkFractSqrt(SK_Fract1/4); REPORTER_ASSERT(reporter, x == SK_Fract1/2); x = SkFractSqrt(SK_Fract1/16); REPORTER_ASSERT(reporter, x == SK_Fract1/4); for (i = 1; i < 100; i++) { x = SkFixedSqrt(SK_Fixed1 * i * i); REPORTER_ASSERT(reporter, x == SK_Fixed1 * i); } for (i = 0; i < 1000; i++) { int value = rand.nextS16(); int max = rand.nextU16(); int clamp = SkClampMax(value, max); int clamp2 = value < 0 ? 0 : (value > max ? max : value); REPORTER_ASSERT(reporter, clamp == clamp2); } for (i = 0; i < 10000; i++) { SkPoint p; // These random values are being treated as 32-bit-patterns, not as // ints; calling SkIntToScalar() here produces crashes. p.setLength((SkScalar) rand.nextS(), (SkScalar) rand.nextS(), SK_Scalar1); check_length(reporter, p, SK_Scalar1); p.setLength((SkScalar) (rand.nextS() >> 13), (SkScalar) (rand.nextS() >> 13), SK_Scalar1); check_length(reporter, p, SK_Scalar1); } { SkFixed result = SkFixedDiv(100, 100); REPORTER_ASSERT(reporter, result == SK_Fixed1); result = SkFixedDiv(1, SK_Fixed1); REPORTER_ASSERT(reporter, result == 1); } unittest_fastfloat(reporter); unittest_isfinite(reporter); #ifdef SkLONGLONG for (i = 0; i < 10000; i++) { SkFixed numer = rand.nextS(); SkFixed denom = rand.nextS(); SkFixed result = SkFixedDiv(numer, denom); SkLONGLONG check = ((SkLONGLONG)numer << 16) / denom; (void)SkCLZ(numer); (void)SkCLZ(denom); REPORTER_ASSERT(reporter, result != (SkFixed)SK_NaN32); if (check > SK_MaxS32) { check = SK_MaxS32; } else if (check < -SK_MaxS32) { check = SK_MinS32; } REPORTER_ASSERT(reporter, result == (int32_t)check); result = SkFractDiv(numer, denom); check = ((SkLONGLONG)numer << 30) / denom; REPORTER_ASSERT(reporter, result != (SkFixed)SK_NaN32); if (check > SK_MaxS32) { check = SK_MaxS32; } else if (check < -SK_MaxS32) { check = SK_MinS32; } REPORTER_ASSERT(reporter, result == (int32_t)check); // make them <= 2^24, so we don't overflow in fixmul numer = numer << 8 >> 8; denom = denom << 8 >> 8; result = SkFixedMul(numer, denom); SkFixed r2 = symmetric_fixmul(numer, denom); // SkASSERT(result == r2); result = SkFixedMul(numer, numer); r2 = SkFixedSquare(numer); REPORTER_ASSERT(reporter, result == r2); if (numer >= 0 && denom >= 0) { SkFixed mean = SkFixedMean(numer, denom); float prod = SkFixedToFloat(numer) * SkFixedToFloat(denom); float fm = sk_float_sqrt(sk_float_abs(prod)); SkFixed mean2 = SkFloatToFixed(fm); int diff = SkAbs32(mean - mean2); REPORTER_ASSERT(reporter, diff <= 1); } { SkFixed mod = SkFixedMod(numer, denom); float n = SkFixedToFloat(numer); float d = SkFixedToFloat(denom); float m = sk_float_mod(n, d); // ensure the same sign REPORTER_ASSERT(reporter, mod == 0 || (mod < 0) == (m < 0)); int diff = SkAbs32(mod - SkFloatToFixed(m)); REPORTER_ASSERT(reporter, (diff >> 7) == 0); } } #endif for (i = 0; i < 10000; i++) { SkFract x = rand.nextU() >> 1; double xx = (double)x / SK_Fract1; SkFract xr = SkFractSqrt(x); SkFract check = SkFloatToFract(sqrt(xx)); REPORTER_ASSERT(reporter, xr == check || xr == check-1 || xr == check+1); xr = SkFixedSqrt(x); xx = (double)x / SK_Fixed1; check = SkFloatToFixed(sqrt(xx)); REPORTER_ASSERT(reporter, xr == check || xr == check-1); xr = SkSqrt32(x); xx = (double)x; check = (int32_t)sqrt(xx); REPORTER_ASSERT(reporter, xr == check || xr == check-1); } #if !defined(SK_SCALAR_IS_FLOAT) { SkFixed s, c; s = SkFixedSinCos(0, &c); REPORTER_ASSERT(reporter, s == 0); REPORTER_ASSERT(reporter, c == SK_Fixed1); } int maxDiff = 0; for (i = 0; i < 1000; i++) { SkFixed rads = rand.nextS() >> 10; double frads = SkFixedToFloat(rads); SkFixed s, c; s = SkScalarSinCos(rads, &c); double fs = sin(frads); double fc = cos(frads); SkFixed is = SkFloatToFixed(fs); SkFixed ic = SkFloatToFixed(fc); maxDiff = SkMax32(maxDiff, SkAbs32(is - s)); maxDiff = SkMax32(maxDiff, SkAbs32(ic - c)); } SkDebugf("SinCos: maximum error = %d\n", maxDiff); #endif #ifdef SK_SCALAR_IS_FLOAT test_blend(reporter); #endif if (false) test_floor(reporter); // disable for now if (false) test_blend31(); // avoid bit rot, suppress warning test_muldivround(reporter); test_clz(reporter); } #include "TestClassDef.h" DEFINE_TESTCLASS("Math", MathTestClass, TestMath) /////////////////////////////////////////////////////////////////////////////// #include "SkEndian.h" template struct PairRec { T fYin; T fYang; }; static void TestEndian(skiatest::Reporter* reporter) { static const PairRec g16[] = { { 0x0, 0x0 }, { 0xFFFF, 0xFFFF }, { 0x1122, 0x2211 }, }; static const PairRec g32[] = { { 0x0, 0x0 }, { 0xFFFFFFFF, 0xFFFFFFFF }, { 0x11223344, 0x44332211 }, }; static const PairRec g64[] = { { 0x0, 0x0 }, { 0xFFFFFFFFFFFFFFFFULL, 0xFFFFFFFFFFFFFFFFULL }, { 0x1122334455667788ULL, 0x8877665544332211ULL }, }; REPORTER_ASSERT(reporter, 0x1122 == SkTEndianSwap16<0x2211>::value); REPORTER_ASSERT(reporter, 0x11223344 == SkTEndianSwap32<0x44332211>::value); REPORTER_ASSERT(reporter, 0x1122334455667788ULL == SkTEndianSwap64<0x8877665544332211ULL>::value); for (size_t i = 0; i < SK_ARRAY_COUNT(g16); ++i) { REPORTER_ASSERT(reporter, g16[i].fYang == SkEndianSwap16(g16[i].fYin)); } for (size_t i = 0; i < SK_ARRAY_COUNT(g32); ++i) { REPORTER_ASSERT(reporter, g32[i].fYang == SkEndianSwap32(g32[i].fYin)); } for (size_t i = 0; i < SK_ARRAY_COUNT(g64); ++i) { REPORTER_ASSERT(reporter, g64[i].fYang == SkEndianSwap64(g64[i].fYin)); } } DEFINE_TESTCLASS("Endian", EndianTestClass, TestEndian)