| /* |
| * Copyright (C) 2006-2008 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "SkMath.h" |
| #include "SkCordic.h" |
| #include "SkFloatBits.h" |
| #include "SkFloatingPoint.h" |
| #include "Sk64.h" |
| #include "SkScalar.h" |
| |
| #ifdef SK_SCALAR_IS_FLOAT |
| const uint32_t gIEEENotANumber = 0x7FFFFFFF; |
| const uint32_t gIEEEInfinity = 0x7F800000; |
| #endif |
| |
| #define sub_shift(zeros, x, n) \ |
| zeros -= n; \ |
| x >>= n |
| |
| int SkCLZ_portable(uint32_t x) { |
| if (x == 0) { |
| return 32; |
| } |
| |
| #ifdef SK_CPU_HAS_CONDITIONAL_INSTR |
| int zeros = 31; |
| if (x & 0xFFFF0000) { |
| sub_shift(zeros, x, 16); |
| } |
| if (x & 0xFF00) { |
| sub_shift(zeros, x, 8); |
| } |
| if (x & 0xF0) { |
| sub_shift(zeros, x, 4); |
| } |
| if (x & 0xC) { |
| sub_shift(zeros, x, 2); |
| } |
| if (x & 0x2) { |
| sub_shift(zeros, x, 1); |
| } |
| #else |
| int zeros = ((x >> 16) - 1) >> 31 << 4; |
| x <<= zeros; |
| |
| int nonzero = ((x >> 24) - 1) >> 31 << 3; |
| zeros += nonzero; |
| x <<= nonzero; |
| |
| nonzero = ((x >> 28) - 1) >> 31 << 2; |
| zeros += nonzero; |
| x <<= nonzero; |
| |
| nonzero = ((x >> 30) - 1) >> 31 << 1; |
| zeros += nonzero; |
| x <<= nonzero; |
| |
| zeros += (~x) >> 31; |
| #endif |
| |
| return zeros; |
| } |
| |
| int32_t SkMulDiv(int32_t numer1, int32_t numer2, int32_t denom) { |
| SkASSERT(denom); |
| |
| Sk64 tmp; |
| tmp.setMul(numer1, numer2); |
| tmp.div(denom, Sk64::kTrunc_DivOption); |
| return tmp.get32(); |
| } |
| |
| int32_t SkMulShift(int32_t a, int32_t b, unsigned shift) { |
| int sign = SkExtractSign(a ^ b); |
| |
| if (shift > 63) { |
| return sign; |
| } |
| |
| a = SkAbs32(a); |
| b = SkAbs32(b); |
| |
| uint32_t ah = a >> 16; |
| uint32_t al = a & 0xFFFF; |
| uint32_t bh = b >> 16; |
| uint32_t bl = b & 0xFFFF; |
| |
| uint32_t A = ah * bh; |
| uint32_t B = ah * bl + al * bh; |
| uint32_t C = al * bl; |
| |
| /* [ A ] |
| [ B ] |
| [ C ] |
| */ |
| uint32_t lo = C + (B << 16); |
| int32_t hi = A + (B >> 16) + (lo < C); |
| |
| if (sign < 0) { |
| hi = -hi - Sk32ToBool(lo); |
| lo = 0 - lo; |
| } |
| |
| if (shift == 0) { |
| #ifdef SK_DEBUGx |
| SkASSERT(((int32_t)lo >> 31) == hi); |
| #endif |
| return lo; |
| } else if (shift >= 32) { |
| return hi >> (shift - 32); |
| } else { |
| #ifdef SK_DEBUGx |
| int32_t tmp = hi >> shift; |
| SkASSERT(tmp == 0 || tmp == -1); |
| #endif |
| // we want (hi << (32 - shift)) | (lo >> shift) but rounded |
| int roundBit = (lo >> (shift - 1)) & 1; |
| return ((hi << (32 - shift)) | (lo >> shift)) + roundBit; |
| } |
| } |
| |
| SkFixed SkFixedMul_portable(SkFixed a, SkFixed b) { |
| #if 0 |
| Sk64 tmp; |
| |
| tmp.setMul(a, b); |
| tmp.shiftRight(16); |
| return tmp.fLo; |
| #elif defined(SkLONGLONG) |
| return static_cast<SkFixed>((SkLONGLONG)a * b >> 16); |
| #else |
| int sa = SkExtractSign(a); |
| int sb = SkExtractSign(b); |
| // now make them positive |
| a = SkApplySign(a, sa); |
| b = SkApplySign(b, sb); |
| |
| uint32_t ah = a >> 16; |
| uint32_t al = a & 0xFFFF; |
| uint32_t bh = b >> 16; |
| uint32_t bl = b & 0xFFFF; |
| |
| uint32_t R = ah * b + al * bh + (al * bl >> 16); |
| |
| return SkApplySign(R, sa ^ sb); |
| #endif |
| } |
| |
| SkFract SkFractMul_portable(SkFract a, SkFract b) { |
| #if 0 |
| Sk64 tmp; |
| tmp.setMul(a, b); |
| return tmp.getFract(); |
| #elif defined(SkLONGLONG) |
| return static_cast<SkFract>((SkLONGLONG)a * b >> 30); |
| #else |
| int sa = SkExtractSign(a); |
| int sb = SkExtractSign(b); |
| // now make them positive |
| a = SkApplySign(a, sa); |
| b = SkApplySign(b, sb); |
| |
| uint32_t ah = a >> 16; |
| uint32_t al = a & 0xFFFF; |
| uint32_t bh = b >> 16; |
| uint32_t bl = b & 0xFFFF; |
| |
| uint32_t A = ah * bh; |
| uint32_t B = ah * bl + al * bh; |
| uint32_t C = al * bl; |
| |
| /* [ A ] |
| [ B ] |
| [ C ] |
| */ |
| uint32_t Lo = C + (B << 16); |
| uint32_t Hi = A + (B >>16) + (Lo < C); |
| |
| SkASSERT((Hi >> 29) == 0); // else overflow |
| |
| int32_t R = (Hi << 2) + (Lo >> 30); |
| |
| return SkApplySign(R, sa ^ sb); |
| #endif |
| } |
| |
| int SkFixedMulCommon(SkFixed a, int b, int bias) { |
| // this function only works if b is 16bits |
| SkASSERT(b == (int16_t)b); |
| SkASSERT(b >= 0); |
| |
| int sa = SkExtractSign(a); |
| a = SkApplySign(a, sa); |
| uint32_t ah = a >> 16; |
| uint32_t al = a & 0xFFFF; |
| uint32_t R = ah * b + ((al * b + bias) >> 16); |
| return SkApplySign(R, sa); |
| } |
| |
| #ifdef SK_DEBUGx |
| #define TEST_FASTINVERT |
| #endif |
| |
| SkFixed SkFixedFastInvert(SkFixed x) { |
| /* Adapted (stolen) from gglRecip() |
| */ |
| |
| if (x == SK_Fixed1) { |
| return SK_Fixed1; |
| } |
| |
| int sign = SkExtractSign(x); |
| uint32_t a = SkApplySign(x, sign); |
| |
| if (a <= 2) { |
| return SkApplySign(SK_MaxS32, sign); |
| } |
| |
| #ifdef TEST_FASTINVERT |
| SkFixed orig = a; |
| uint32_t slow = SkFixedDiv(SK_Fixed1, a); |
| #endif |
| |
| // normalize a |
| int lz = SkCLZ(a); |
| a = a << lz >> 16; |
| |
| // compute 1/a approximation (0.5 <= a < 1.0) |
| uint32_t r = 0x17400 - a; // (2.90625 (~2.914) - 2*a) >> 1 |
| |
| // Newton-Raphson iteration: |
| // x = r*(2 - a*r) = ((r/2)*(1 - a*r/2))*4 |
| r = ( (0x10000 - ((a*r)>>16)) * r ) >> 15; |
| r = ( (0x10000 - ((a*r)>>16)) * r ) >> (30 - lz); |
| |
| #ifdef TEST_FASTINVERT |
| SkDebugf("SkFixedFastInvert(%x %g) = %x %g Slow[%x %g]\n", |
| orig, orig/65536., |
| r, r/65536., |
| slow, slow/65536.); |
| #endif |
| |
| return SkApplySign(r, sign); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #define DIVBITS_ITER(n) \ |
| case n: \ |
| if ((numer = (numer << 1) - denom) >= 0) \ |
| result |= 1 << (n - 1); else numer += denom |
| |
| int32_t SkDivBits(int32_t numer, int32_t denom, int shift_bias) { |
| SkASSERT(denom != 0); |
| if (numer == 0) { |
| return 0; |
| } |
| |
| // make numer and denom positive, and sign hold the resulting sign |
| int32_t sign = SkExtractSign(numer ^ denom); |
| numer = SkAbs32(numer); |
| denom = SkAbs32(denom); |
| |
| int nbits = SkCLZ(numer) - 1; |
| int dbits = SkCLZ(denom) - 1; |
| int bits = shift_bias - nbits + dbits; |
| |
| if (bits < 0) { // answer will underflow |
| return 0; |
| } |
| if (bits > 31) { // answer will overflow |
| return SkApplySign(SK_MaxS32, sign); |
| } |
| |
| denom <<= dbits; |
| numer <<= nbits; |
| |
| SkFixed result = 0; |
| |
| // do the first one |
| if ((numer -= denom) >= 0) { |
| result = 1; |
| } else { |
| numer += denom; |
| } |
| |
| // Now fall into our switch statement if there are more bits to compute |
| if (bits > 0) { |
| // make room for the rest of the answer bits |
| result <<= bits; |
| switch (bits) { |
| DIVBITS_ITER(31); DIVBITS_ITER(30); DIVBITS_ITER(29); |
| DIVBITS_ITER(28); DIVBITS_ITER(27); DIVBITS_ITER(26); |
| DIVBITS_ITER(25); DIVBITS_ITER(24); DIVBITS_ITER(23); |
| DIVBITS_ITER(22); DIVBITS_ITER(21); DIVBITS_ITER(20); |
| DIVBITS_ITER(19); DIVBITS_ITER(18); DIVBITS_ITER(17); |
| DIVBITS_ITER(16); DIVBITS_ITER(15); DIVBITS_ITER(14); |
| DIVBITS_ITER(13); DIVBITS_ITER(12); DIVBITS_ITER(11); |
| DIVBITS_ITER(10); DIVBITS_ITER( 9); DIVBITS_ITER( 8); |
| DIVBITS_ITER( 7); DIVBITS_ITER( 6); DIVBITS_ITER( 5); |
| DIVBITS_ITER( 4); DIVBITS_ITER( 3); DIVBITS_ITER( 2); |
| // we merge these last two together, makes GCC make better ARM |
| default: |
| DIVBITS_ITER( 1); |
| } |
| } |
| |
| if (result < 0) { |
| result = SK_MaxS32; |
| } |
| return SkApplySign(result, sign); |
| } |
| |
| /* mod(float numer, float denom) seems to always return the sign |
| of the numer, so that's what we do too |
| */ |
| SkFixed SkFixedMod(SkFixed numer, SkFixed denom) { |
| int sn = SkExtractSign(numer); |
| int sd = SkExtractSign(denom); |
| |
| numer = SkApplySign(numer, sn); |
| denom = SkApplySign(denom, sd); |
| |
| if (numer < denom) { |
| return SkApplySign(numer, sn); |
| } else if (numer == denom) { |
| return 0; |
| } else { |
| SkFixed div = SkFixedDiv(numer, denom); |
| return SkApplySign(SkFixedMul(denom, div & 0xFFFF), sn); |
| } |
| } |
| |
| /* www.worldserver.com/turk/computergraphics/FixedSqrt.pdf |
| */ |
| int32_t SkSqrtBits(int32_t x, int count) { |
| SkASSERT(x >= 0 && count > 0 && (unsigned)count <= 30); |
| |
| uint32_t root = 0; |
| uint32_t remHi = 0; |
| uint32_t remLo = x; |
| |
| do { |
| root <<= 1; |
| |
| remHi = (remHi<<2) | (remLo>>30); |
| remLo <<= 2; |
| |
| uint32_t testDiv = (root << 1) + 1; |
| if (remHi >= testDiv) { |
| remHi -= testDiv; |
| root++; |
| } |
| } while (--count >= 0); |
| |
| return root; |
| } |
| |
| int32_t SkCubeRootBits(int32_t value, int bits) { |
| SkASSERT(bits > 0); |
| |
| int sign = SkExtractSign(value); |
| value = SkApplySign(value, sign); |
| |
| uint32_t root = 0; |
| uint32_t curr = (uint32_t)value >> 30; |
| value <<= 2; |
| |
| do { |
| root <<= 1; |
| uint32_t guess = root * root + root; |
| guess = (guess << 1) + guess; // guess *= 3 |
| if (guess < curr) { |
| curr -= guess + 1; |
| root |= 1; |
| } |
| curr = (curr << 3) | ((uint32_t)value >> 29); |
| value <<= 3; |
| } while (--bits); |
| |
| return SkApplySign(root, sign); |
| } |
| |
| SkFixed SkFixedMean(SkFixed a, SkFixed b) { |
| Sk64 tmp; |
| |
| tmp.setMul(a, b); |
| return tmp.getSqrt(); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #ifdef SK_SCALAR_IS_FLOAT |
| float SkScalarSinCos(float radians, float* cosValue) { |
| float sinValue = sk_float_sin(radians); |
| |
| if (cosValue) { |
| *cosValue = sk_float_cos(radians); |
| if (SkScalarNearlyZero(*cosValue)) { |
| *cosValue = 0; |
| } |
| } |
| |
| if (SkScalarNearlyZero(sinValue)) { |
| sinValue = 0; |
| } |
| return sinValue; |
| } |
| #endif |
| |
| #define INTERP_SINTABLE |
| #define BUILD_TABLE_AT_RUNTIMEx |
| |
| #define kTableSize 256 |
| |
| #ifdef BUILD_TABLE_AT_RUNTIME |
| static uint16_t gSkSinTable[kTableSize]; |
| |
| static void build_sintable(uint16_t table[]) { |
| for (int i = 0; i < kTableSize; i++) { |
| double rad = i * 3.141592653589793 / (2*kTableSize); |
| double val = sin(rad); |
| int ival = (int)(val * SK_Fixed1); |
| table[i] = SkToU16(ival); |
| } |
| } |
| #else |
| #include "SkSinTable.h" |
| #endif |
| |
| #define SK_Fract1024SizeOver2PI 0x28BE60 /* floatToFract(1024 / 2PI) */ |
| |
| #ifdef INTERP_SINTABLE |
| static SkFixed interp_table(const uint16_t table[], int index, int partial255) { |
| SkASSERT((unsigned)index < kTableSize); |
| SkASSERT((unsigned)partial255 <= 255); |
| |
| SkFixed lower = table[index]; |
| SkFixed upper = (index == kTableSize - 1) ? SK_Fixed1 : table[index + 1]; |
| |
| SkASSERT(lower < upper); |
| SkASSERT(lower >= 0); |
| SkASSERT(upper <= SK_Fixed1); |
| |
| partial255 += (partial255 >> 7); |
| return lower + ((upper - lower) * partial255 >> 8); |
| } |
| #endif |
| |
| SkFixed SkFixedSinCos(SkFixed radians, SkFixed* cosValuePtr) { |
| SkASSERT(SK_ARRAY_COUNT(gSkSinTable) == kTableSize); |
| |
| #ifdef BUILD_TABLE_AT_RUNTIME |
| static bool gFirstTime = true; |
| if (gFirstTime) { |
| build_sintable(gSinTable); |
| gFirstTime = false; |
| } |
| #endif |
| |
| // make radians positive |
| SkFixed sinValue, cosValue; |
| int32_t cosSign = 0; |
| int32_t sinSign = SkExtractSign(radians); |
| radians = SkApplySign(radians, sinSign); |
| // scale it to 0...1023 ... |
| |
| #ifdef INTERP_SINTABLE |
| radians = SkMulDiv(radians, 2 * kTableSize * 256, SK_FixedPI); |
| int findex = radians & (kTableSize * 256 - 1); |
| int index = findex >> 8; |
| int partial = findex & 255; |
| sinValue = interp_table(gSkSinTable, index, partial); |
| |
| findex = kTableSize * 256 - findex - 1; |
| index = findex >> 8; |
| partial = findex & 255; |
| cosValue = interp_table(gSkSinTable, index, partial); |
| |
| int quad = ((unsigned)radians / (kTableSize * 256)) & 3; |
| #else |
| radians = SkMulDiv(radians, 2 * kTableSize, SK_FixedPI); |
| int index = radians & (kTableSize - 1); |
| |
| if (index == 0) { |
| sinValue = 0; |
| cosValue = SK_Fixed1; |
| } else { |
| sinValue = gSkSinTable[index]; |
| cosValue = gSkSinTable[kTableSize - index]; |
| } |
| int quad = ((unsigned)radians / kTableSize) & 3; |
| #endif |
| |
| if (quad & 1) { |
| SkTSwap<SkFixed>(sinValue, cosValue); |
| } |
| if (quad & 2) { |
| sinSign = ~sinSign; |
| } |
| if (((quad - 1) & 2) == 0) { |
| cosSign = ~cosSign; |
| } |
| |
| // restore the sign for negative angles |
| sinValue = SkApplySign(sinValue, sinSign); |
| cosValue = SkApplySign(cosValue, cosSign); |
| |
| #ifdef SK_DEBUG |
| if (1) { |
| SkFixed sin2 = SkFixedMul(sinValue, sinValue); |
| SkFixed cos2 = SkFixedMul(cosValue, cosValue); |
| int diff = cos2 + sin2 - SK_Fixed1; |
| SkASSERT(SkAbs32(diff) <= 7); |
| } |
| #endif |
| |
| if (cosValuePtr) { |
| *cosValuePtr = cosValue; |
| } |
| return sinValue; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| SkFixed SkFixedTan(SkFixed radians) { return SkCordicTan(radians); } |
| SkFixed SkFixedASin(SkFixed x) { return SkCordicASin(x); } |
| SkFixed SkFixedACos(SkFixed x) { return SkCordicACos(x); } |
| SkFixed SkFixedATan2(SkFixed y, SkFixed x) { return SkCordicATan2(y, x); } |
| SkFixed SkFixedExp(SkFixed x) { return SkCordicExp(x); } |
| SkFixed SkFixedLog(SkFixed x) { return SkCordicLog(x); } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #ifdef SK_DEBUG |
| |
| #include "SkRandom.h" |
| |
| #if defined(SkLONGLONG) && defined(SK_SUPPORT_UNITTEST) |
| 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 |
| |
| #include "SkPoint.h" |
| |
| #ifdef SK_SUPPORT_UNITTEST |
| static void check_length(const SkPoint& p, SkScalar targetLen) { |
| #ifdef SK_CAN_USE_FLOAT |
| float x = SkScalarToFloat(p.fX); |
| float y = SkScalarToFloat(p.fY); |
| float len = sk_float_sqrt(x*x + y*y); |
| |
| len /= SkScalarToFloat(targetLen); |
| |
| SkASSERT(len > 0.999f && len < 1.001f); |
| #endif |
| } |
| #endif |
| |
| #if defined(SK_CAN_USE_FLOAT) && defined(SK_SUPPORT_UNITTEST) |
| |
| 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 si == SK_MaxS32 || si == SK_MinS32; |
| } |
| // for out of range, C is undefined, but skia always should return NaN32 |
| if (x > SK_MaxS32) { |
| return si == SK_MaxS32; |
| } |
| if (x < -SK_MaxS32) { |
| return si == SK_MinS32; |
| } |
| return si == ni; |
| } |
| |
| static void assert_float_equal(const char op[], float x, uint32_t ni, |
| uint32_t si) { |
| if (!equal_float_native_skia(x, ni, si)) { |
| SkDebugf("-- %s float %g bits %x native %x skia %x\n", op, x, ni, si); |
| SkASSERT(!"oops"); |
| } |
| } |
| |
| static void test_float_cast(float x) { |
| int ix = (int)x; |
| int iix = SkFloatToIntCast(x); |
| assert_float_equal("cast", x, ix, iix); |
| } |
| |
| static void test_float_floor(float x) { |
| int ix = (int)floor(x); |
| int iix = SkFloatToIntFloor(x); |
| assert_float_equal("floor", x, ix, iix); |
| } |
| |
| static void test_float_round(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("round", x, ix, iix); |
| } |
| |
| static void test_float_ceil(float x) { |
| int ix = (int)ceil(x); |
| int iix = SkFloatToIntCeil(x); |
| assert_float_equal("ceil", x, ix, iix); |
| } |
| |
| static void test_float_conversions(float x) { |
| test_float_cast(x); |
| test_float_floor(x); |
| test_float_round(x); |
| test_float_ceil(x); |
| } |
| |
| static void test_int2float(int ival) { |
| float x0 = (float)ival; |
| float x1 = SkIntToFloatCast(ival); |
| float x2 = SkIntToFloatCast_NoOverflowCheck(ival); |
| SkASSERT(x0 == x1); |
| SkASSERT(x0 == x2); |
| } |
| |
| static void unittest_fastfloat() { |
| 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++) { |
| // SkDebugf("---- test floats %g %d\n", gFloats[i], (int)gFloats[i]); |
| test_float_conversions(gFloats[i]); |
| test_float_conversions(-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(x); |
| } |
| |
| test_int2float(0); |
| test_int2float(1); |
| test_int2float(-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(ival); |
| test_int2float(-ival); |
| } |
| } |
| } |
| |
| #endif |
| |
| #ifdef SK_SUPPORT_UNITTEST |
| static void test_muldiv255() { |
| #ifdef SK_CAN_USE_FLOAT |
| 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); |
| |
| SkASSERT(iround == round); |
| SkASSERT(itrunc == trunc); |
| |
| SkASSERT(itrunc <= iround); |
| SkASSERT(iround <= a); |
| SkASSERT(iround <= b); |
| } |
| } |
| #endif |
| } |
| #endif |
| |
| void SkMath::UnitTest() { |
| #ifdef SK_SUPPORT_UNITTEST |
| int i; |
| int32_t x; |
| SkRandom rand; |
| |
| SkToS8(127); SkToS8(-128); SkToU8(255); |
| SkToS16(32767); SkToS16(-32768); SkToU16(65535); |
| SkToS32(2*1024*1024); SkToS32(-2*1024*1024); SkToU32(4*1024*1024); |
| |
| SkCordic_UnitTest(); |
| |
| // 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(); |
| |
| #ifdef SK_DEBUG |
| { |
| SkScalar x = SK_ScalarNaN; |
| SkASSERT(SkScalarIsNaN(x)); |
| } |
| #endif |
| |
| for (i = 1; i <= 10; i++) { |
| x = SkCubeRootBits(i*i*i, 11); |
| SkASSERT(x == i); |
| } |
| |
| x = SkFixedSqrt(SK_Fixed1); |
| SkASSERT(x == SK_Fixed1); |
| x = SkFixedSqrt(SK_Fixed1/4); |
| SkASSERT(x == SK_Fixed1/2); |
| x = SkFixedSqrt(SK_Fixed1*4); |
| SkASSERT(x == SK_Fixed1*2); |
| |
| x = SkFractSqrt(SK_Fract1); |
| SkASSERT(x == SK_Fract1); |
| x = SkFractSqrt(SK_Fract1/4); |
| SkASSERT(x == SK_Fract1/2); |
| x = SkFractSqrt(SK_Fract1/16); |
| SkASSERT(x == SK_Fract1/4); |
| |
| for (i = 1; i < 100; i++) { |
| x = SkFixedSqrt(SK_Fixed1 * i * i); |
| SkASSERT(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); |
| SkASSERT(clamp == clamp2); |
| } |
| |
| for (i = 0; i < 100000; i++) { |
| SkPoint p; |
| |
| p.setLength(rand.nextS(), rand.nextS(), SK_Scalar1); |
| check_length(p, SK_Scalar1); |
| p.setLength(rand.nextS() >> 13, rand.nextS() >> 13, SK_Scalar1); |
| check_length(p, SK_Scalar1); |
| } |
| |
| { |
| SkFixed result = SkFixedDiv(100, 100); |
| SkASSERT(result == SK_Fixed1); |
| result = SkFixedDiv(1, SK_Fixed1); |
| SkASSERT(result == 1); |
| } |
| |
| #ifdef SK_CAN_USE_FLOAT |
| unittest_fastfloat(); |
| #endif |
| |
| #ifdef SkLONGLONG |
| for (i = 0; i < 100000; 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); |
| |
| SkASSERT(result != (SkFixed)SK_NaN32); |
| if (check > SK_MaxS32) { |
| check = SK_MaxS32; |
| } else if (check < -SK_MaxS32) { |
| check = SK_MinS32; |
| } |
| SkASSERT(result == (int32_t)check); |
| |
| result = SkFractDiv(numer, denom); |
| check = ((SkLONGLONG)numer << 30) / denom; |
| |
| SkASSERT(result != (SkFixed)SK_NaN32); |
| if (check > SK_MaxS32) { |
| check = SK_MaxS32; |
| } else if (check < -SK_MaxS32) { |
| check = SK_MinS32; |
| } |
| SkASSERT(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); |
| SkASSERT(result == r2); |
| |
| #ifdef SK_CAN_USE_FLOAT |
| if (numer >= 0 && denom >= 0) { |
| SkFixed mean = SkFixedMean(numer, denom); |
| float fm = sk_float_sqrt(sk_float_abs(SkFixedToFloat(numer) * SkFixedToFloat(denom))); |
| SkFixed mean2 = SkFloatToFixed(fm); |
| int diff = SkAbs32(mean - mean2); |
| SkASSERT(diff <= 1); |
| } |
| |
| { |
| SkFixed mod = SkFixedMod(numer, denom); |
| float n = SkFixedToFloat(numer); |
| float d = SkFixedToFloat(denom); |
| float m = sk_float_mod(n, d); |
| #if 0 |
| SkDebugf("%g mod %g = %g [%g]\n", |
| SkFixedToFloat(numer), SkFixedToFloat(denom), |
| SkFixedToFloat(mod), m); |
| #endif |
| SkASSERT(mod == 0 || (mod < 0) == (m < 0)); // ensure the same sign |
| int diff = SkAbs32(mod - SkFloatToFixed(m)); |
| SkASSERT((diff >> 7) == 0); |
| } |
| #endif |
| } |
| #endif |
| |
| #ifdef SK_CAN_USE_FLOAT |
| for (i = 0; i < 100000; i++) { |
| SkFract x = rand.nextU() >> 1; |
| double xx = (double)x / SK_Fract1; |
| SkFract xr = SkFractSqrt(x); |
| SkFract check = SkFloatToFract(sqrt(xx)); |
| SkASSERT(xr == check || xr == check-1 || xr == check+1); |
| |
| xr = SkFixedSqrt(x); |
| xx = (double)x / SK_Fixed1; |
| check = SkFloatToFixed(sqrt(xx)); |
| SkASSERT(xr == check || xr == check-1); |
| |
| xr = SkSqrt32(x); |
| xx = (double)x; |
| check = (int32_t)sqrt(xx); |
| SkASSERT(xr == check || xr == check-1); |
| } |
| #endif |
| |
| #if !defined(SK_SCALAR_IS_FLOAT) && defined(SK_CAN_USE_FLOAT) |
| { |
| SkFixed s, c; |
| s = SkFixedSinCos(0, &c); |
| SkASSERT(s == 0); |
| SkASSERT(c == SK_Fixed1); |
| } |
| |
| int maxDiff = 0; |
| for (i = 0; i < 10000; 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 |
| #endif |
| } |
| |
| #endif |
