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Diffstat (limited to 'chromium/third_party/skia/include/core/SkScalar.h')
| -rw-r--r-- | chromium/third_party/skia/include/core/SkScalar.h | 411 |
1 files changed, 160 insertions, 251 deletions
diff --git a/chromium/third_party/skia/include/core/SkScalar.h b/chromium/third_party/skia/include/core/SkScalar.h index cc1cf99ac80..b37cf5c998f 100644 --- a/chromium/third_party/skia/include/core/SkScalar.h +++ b/chromium/third_party/skia/include/core/SkScalar.h @@ -1,4 +1,3 @@ - /* * Copyright 2006 The Android Open Source Project * @@ -6,265 +5,185 @@ * found in the LICENSE file. */ - #ifndef SkScalar_DEFINED #define SkScalar_DEFINED #include "SkFixed.h" #include "SkFloatingPoint.h" -/** \file SkScalar.h - - Types and macros for the data type SkScalar. This is the fractional numeric type - that, depending on the compile-time flag SK_SCALAR_IS_FLOAT, may be implemented - either as an IEEE float, or as a 16.16 SkFixed. The macros in this file are written - to allow the calling code to manipulate SkScalar values without knowing which representation - is in effect. -*/ - -#ifdef SK_SCALAR_IS_FLOAT - - /** SkScalar is our type for fractional values and coordinates. Depending on - compile configurations, it is either represented as an IEEE float, or - as a 16.16 fixed point integer. - */ - typedef float SkScalar; - - /** SK_Scalar1 is defined to be 1.0 represented as an SkScalar - */ - #define SK_Scalar1 (1.0f) - /** SK_Scalar1 is defined to be 1/2 represented as an SkScalar - */ - #define SK_ScalarHalf (0.5f) - /** SK_ScalarInfinity is defined to be infinity as an SkScalar - */ - #define SK_ScalarInfinity SK_FloatInfinity - /** SK_ScalarNegativeInfinity is defined to be negative infinity as an SkScalar - */ - #define SK_ScalarNegativeInfinity SK_FloatNegativeInfinity - /** SK_ScalarMax is defined to be the largest value representable as an SkScalar - */ - #define SK_ScalarMax (3.402823466e+38f) - /** SK_ScalarMin is defined to be the smallest value representable as an SkScalar - */ - #define SK_ScalarMin (-SK_ScalarMax) - /** SK_ScalarNaN is defined to be 'Not a Number' as an SkScalar - */ - #define SK_ScalarNaN SK_FloatNaN - /** SkScalarIsNaN(n) returns true if argument is not a number - */ - static inline bool SkScalarIsNaN(float x) { return x != x; } - - /** Returns true if x is not NaN and not infinite */ - static inline bool SkScalarIsFinite(float x) { - // We rely on the following behavior of infinities and nans - // 0 * finite --> 0 - // 0 * infinity --> NaN - // 0 * NaN --> NaN - float prod = x * 0; - // At this point, prod will either be NaN or 0 - // Therefore we can return (prod == prod) or (0 == prod). - return prod == prod; - } - - /** SkIntToScalar(n) returns its integer argument as an SkScalar - */ - #define SkIntToScalar(n) ((float)(n)) - /** SkFixedToScalar(n) returns its SkFixed argument as an SkScalar - */ - #define SkFixedToScalar(x) SkFixedToFloat(x) - /** SkScalarToFixed(n) returns its SkScalar argument as an SkFixed - */ - #define SkScalarToFixed(x) SkFloatToFixed(x) - - #define SkScalarToFloat(n) (n) -#ifndef SK_SCALAR_TO_FLOAT_EXCLUDED - #define SkFloatToScalar(n) (n) -#endif - - #define SkScalarToDouble(n) (double)(n) - #define SkDoubleToScalar(n) (float)(n) - - /** SkScalarFraction(x) returns the signed fractional part of the argument - */ - #define SkScalarFraction(x) sk_float_mod(x, 1.0f) - - #define SkScalarFloorToScalar(x) sk_float_floor(x) - #define SkScalarCeilToScalar(x) sk_float_ceil(x) - #define SkScalarRoundToScalar(x) sk_float_floor((x) + 0.5f) - - #define SkScalarFloorToInt(x) sk_float_floor2int(x) - #define SkScalarCeilToInt(x) sk_float_ceil2int(x) - #define SkScalarRoundToInt(x) sk_float_round2int(x) - #define SkScalarTruncToInt(x) static_cast<int>(x) +//#define SK_SUPPORT_DEPRECATED_SCALARROUND - /** Returns the absolute value of the specified SkScalar - */ - #define SkScalarAbs(x) sk_float_abs(x) - /** Return x with the sign of y - */ - #define SkScalarCopySign(x, y) sk_float_copysign(x, y) - /** Returns the value pinned between 0 and max inclusive - */ - inline SkScalar SkScalarClampMax(SkScalar x, SkScalar max) { - return x < 0 ? 0 : x > max ? max : x; - } - /** Returns the value pinned between min and max inclusive - */ - inline SkScalar SkScalarPin(SkScalar x, SkScalar min, SkScalar max) { - return x < min ? min : x > max ? max : x; - } - /** Returns the specified SkScalar squared (x*x) - */ - inline SkScalar SkScalarSquare(SkScalar x) { return x * x; } - /** Returns the product of two SkScalars - */ - #define SkScalarMul(a, b) ((float)(a) * (b)) - /** Returns the product of two SkScalars plus a third SkScalar - */ - #define SkScalarMulAdd(a, b, c) ((float)(a) * (b) + (c)) - /** Returns the product of a SkScalar and an int rounded to the nearest integer value - */ - #define SkScalarMulRound(a, b) SkScalarRound((float)(a) * (b)) - /** Returns the product of a SkScalar and an int promoted to the next larger int - */ - #define SkScalarMulCeil(a, b) SkScalarCeil((float)(a) * (b)) - /** Returns the product of a SkScalar and an int truncated to the next smaller int - */ - #define SkScalarMulFloor(a, b) SkScalarFloor((float)(a) * (b)) - /** Returns the quotient of two SkScalars (a/b) - */ - #define SkScalarDiv(a, b) ((float)(a) / (b)) - /** Returns the mod of two SkScalars (a mod b) - */ - #define SkScalarMod(x,y) sk_float_mod(x,y) - /** Returns the product of the first two arguments, divided by the third argument - */ - #define SkScalarMulDiv(a, b, c) ((float)(a) * (b) / (c)) - /** Returns the multiplicative inverse of the SkScalar (1/x) - */ - #define SkScalarInvert(x) (SK_Scalar1 / (x)) - #define SkScalarFastInvert(x) (SK_Scalar1 / (x)) - /** Returns the square root of the SkScalar - */ - #define SkScalarSqrt(x) sk_float_sqrt(x) - /** Returns b to the e - */ - #define SkScalarPow(b, e) sk_float_pow(b, e) - /** Returns the average of two SkScalars (a+b)/2 - */ - #define SkScalarAve(a, b) (((a) + (b)) * 0.5f) - /** Returns the geometric mean of two SkScalars - */ - #define SkScalarMean(a, b) sk_float_sqrt((float)(a) * (b)) - /** Returns one half of the specified SkScalar - */ - #define SkScalarHalf(a) ((a) * 0.5f) - - #define SK_ScalarSqrt2 1.41421356f - #define SK_ScalarPI 3.14159265f - #define SK_ScalarTanPIOver8 0.414213562f - #define SK_ScalarRoot2Over2 0.707106781f - - #define SkDegreesToRadians(degrees) ((degrees) * (SK_ScalarPI / 180)) - float SkScalarSinCos(SkScalar radians, SkScalar* cosValue); - #define SkScalarSin(radians) (float)sk_float_sin(radians) - #define SkScalarCos(radians) (float)sk_float_cos(radians) - #define SkScalarTan(radians) (float)sk_float_tan(radians) - #define SkScalarASin(val) (float)sk_float_asin(val) - #define SkScalarACos(val) (float)sk_float_acos(val) - #define SkScalarATan2(y, x) (float)sk_float_atan2(y,x) - #define SkScalarExp(x) (float)sk_float_exp(x) - #define SkScalarLog(x) (float)sk_float_log(x) - - inline SkScalar SkMaxScalar(SkScalar a, SkScalar b) { return a > b ? a : b; } - inline SkScalar SkMinScalar(SkScalar a, SkScalar b) { return a < b ? a : b; } +typedef float SkScalar; - static inline bool SkScalarIsInt(SkScalar x) { - return x == (float)(int)x; - } -#else - typedef SkFixed SkScalar; +/** SK_Scalar1 is defined to be 1.0 represented as an SkScalar +*/ +#define SK_Scalar1 (1.0f) +/** SK_Scalar1 is defined to be 1/2 represented as an SkScalar +*/ +#define SK_ScalarHalf (0.5f) +/** SK_ScalarInfinity is defined to be infinity as an SkScalar +*/ +#define SK_ScalarInfinity SK_FloatInfinity +/** SK_ScalarNegativeInfinity is defined to be negative infinity as an SkScalar +*/ +#define SK_ScalarNegativeInfinity SK_FloatNegativeInfinity +/** SK_ScalarMax is defined to be the largest value representable as an SkScalar +*/ +#define SK_ScalarMax (3.402823466e+38f) +/** SK_ScalarMin is defined to be the smallest value representable as an SkScalar +*/ +#define SK_ScalarMin (-SK_ScalarMax) +/** SK_ScalarNaN is defined to be 'Not a Number' as an SkScalar +*/ +#define SK_ScalarNaN SK_FloatNaN +/** SkScalarIsNaN(n) returns true if argument is not a number +*/ +static inline bool SkScalarIsNaN(float x) { return x != x; } + +/** Returns true if x is not NaN and not infinite */ +static inline bool SkScalarIsFinite(float x) { + // We rely on the following behavior of infinities and nans + // 0 * finite --> 0 + // 0 * infinity --> NaN + // 0 * NaN --> NaN + float prod = x * 0; + // At this point, prod will either be NaN or 0 + // Therefore we can return (prod == prod) or (0 == prod). + return prod == prod; +} - #define SK_Scalar1 SK_Fixed1 - #define SK_ScalarHalf SK_FixedHalf - #define SK_ScalarInfinity SK_FixedMax - #define SK_ScalarNegativeInfinity SK_FixedMin - #define SK_ScalarMax SK_FixedMax - #define SK_ScalarMin SK_FixedMin - #define SK_ScalarNaN SK_FixedNaN - #define SkScalarIsNaN(x) ((x) == SK_FixedNaN) - #define SkScalarIsFinite(x) ((x) != SK_FixedNaN) +/** SkIntToScalar(n) returns its integer argument as an SkScalar +*/ +#define SkIntToScalar(n) ((float)(n)) +/** SkFixedToScalar(n) returns its SkFixed argument as an SkScalar +*/ +#define SkFixedToScalar(x) SkFixedToFloat(x) +/** SkScalarToFixed(n) returns its SkScalar argument as an SkFixed +*/ +#define SkScalarToFixed(x) SkFloatToFixed(x) - #define SkIntToScalar(n) SkIntToFixed(n) - #define SkFixedToScalar(x) (x) - #define SkScalarToFixed(x) (x) - #define SkScalarToFloat(n) SkFixedToFloat(n) +#define SkScalarToFloat(n) (n) #ifndef SK_SCALAR_TO_FLOAT_EXCLUDED - #define SkFloatToScalar(n) SkFloatToFixed(n) +#define SkFloatToScalar(n) (n) #endif - #define SkScalarToDouble(n) SkFixedToDouble(n) - #define SkDoubleToScalar(n) SkDoubleToFixed(n) - #define SkScalarFraction(x) SkFixedFraction(x) - - #define SkScalarFloorToScalar(x) SkFixedFloorToFixed(x) - #define SkScalarCeilToScalar(x) SkFixedCeilToFixed(x) - #define SkScalarRoundToScalar(x) SkFixedRoundToFixed(x) - - #define SkScalarFloorToInt(x) SkFixedFloorToInt(x) - #define SkScalarCeilToInt(x) SkFixedCeilToInt(x) - #define SkScalarRoundToInt(x) SkFixedRoundToInt(x) - #define SkScalarTruncToInt(x) (((x) < 0) ? SkScalarCeilToInt(x) : SkScalarFloorToInt(x)) +#define SkScalarToDouble(n) (double)(n) +#define SkDoubleToScalar(n) (float)(n) - #define SkScalarAbs(x) SkFixedAbs(x) - #define SkScalarCopySign(x, y) SkCopySign32(x, y) - #define SkScalarClampMax(x, max) SkClampMax(x, max) - #define SkScalarPin(x, min, max) SkPin32(x, min, max) - #define SkScalarSquare(x) SkFixedSquare(x) - #define SkScalarMul(a, b) SkFixedMul(a, b) - #define SkScalarMulAdd(a, b, c) SkFixedMulAdd(a, b, c) - #define SkScalarMulRound(a, b) SkFixedMulCommon(a, b, SK_FixedHalf) - #define SkScalarMulCeil(a, b) SkFixedMulCommon(a, b, SK_Fixed1 - 1) - #define SkScalarMulFloor(a, b) SkFixedMulCommon(a, b, 0) - #define SkScalarDiv(a, b) SkFixedDiv(a, b) - #define SkScalarMod(a, b) SkFixedMod(a, b) - #define SkScalarMulDiv(a, b, c) SkMulDiv(a, b, c) - #define SkScalarInvert(x) SkFixedInvert(x) - #define SkScalarFastInvert(x) SkFixedFastInvert(x) - #define SkScalarSqrt(x) SkFixedSqrt(x) - #define SkScalarAve(a, b) SkFixedAve(a, b) - #define SkScalarMean(a, b) SkFixedMean(a, b) - #define SkScalarHalf(a) ((a) >> 1) +/** SkScalarFraction(x) returns the signed fractional part of the argument +*/ +#define SkScalarFraction(x) sk_float_mod(x, 1.0f) - #define SK_ScalarSqrt2 SK_FixedSqrt2 - #define SK_ScalarPI SK_FixedPI - #define SK_ScalarTanPIOver8 SK_FixedTanPIOver8 - #define SK_ScalarRoot2Over2 SK_FixedRoot2Over2 +#define SkScalarFloorToScalar(x) sk_float_floor(x) +#define SkScalarCeilToScalar(x) sk_float_ceil(x) +#define SkScalarRoundToScalar(x) sk_float_floor((x) + 0.5f) - #define SkDegreesToRadians(degrees) SkFractMul(degrees, SK_FractPIOver180) - #define SkScalarSinCos(radians, cosPtr) SkFixedSinCos(radians, cosPtr) - #define SkScalarSin(radians) SkFixedSin(radians) - #define SkScalarCos(radians) SkFixedCos(radians) - #define SkScalarTan(val) SkFixedTan(val) - #define SkScalarASin(val) SkFixedASin(val) - #define SkScalarACos(val) SkFixedACos(val) - #define SkScalarATan2(y, x) SkFixedATan2(y,x) - #define SkScalarExp(x) SkFixedExp(x) - #define SkScalarLog(x) SkFixedLog(x) +#define SkScalarFloorToInt(x) sk_float_floor2int(x) +#define SkScalarCeilToInt(x) sk_float_ceil2int(x) +#define SkScalarRoundToInt(x) sk_float_round2int(x) +#define SkScalarTruncToInt(x) static_cast<int>(x) - #define SkMaxScalar(a, b) SkMax32(a, b) - #define SkMinScalar(a, b) SkMin32(a, b) +/** + * Variant of SkScalarRoundToInt, that performs the rounding step (adding 0.5) explicitly using + * double, to avoid possibly losing the low bit(s) of the answer before calling floor(). + * + * This routine will likely be slower than SkScalarRoundToInt(), and should only be used when the + * extra precision is known to be valuable. + * + * In particular, this catches the following case: + * SkScalar x = 0.49999997; + * int ix = SkScalarRoundToInt(x); + * SkASSERT(0 == ix); // <--- fails + * ix = SkDScalarRoundToInt(x); + * SkASSERT(0 == ix); // <--- succeeds + */ +static inline int SkDScalarRoundToInt(SkScalar x) { + double xx = x; + xx += 0.5; + return (int)floor(xx); +} - static inline bool SkScalarIsInt(SkFixed x) { - return 0 == (x & 0xffff); - } -#endif +/** Returns the absolute value of the specified SkScalar +*/ +#define SkScalarAbs(x) sk_float_abs(x) +/** Return x with the sign of y + */ +#define SkScalarCopySign(x, y) sk_float_copysign(x, y) +/** Returns the value pinned between 0 and max inclusive +*/ +inline SkScalar SkScalarClampMax(SkScalar x, SkScalar max) { + return x < 0 ? 0 : x > max ? max : x; +} +/** Returns the value pinned between min and max inclusive +*/ +inline SkScalar SkScalarPin(SkScalar x, SkScalar min, SkScalar max) { + return x < min ? min : x > max ? max : x; +} +/** Returns the specified SkScalar squared (x*x) +*/ +inline SkScalar SkScalarSquare(SkScalar x) { return x * x; } +/** Returns the product of two SkScalars +*/ +#define SkScalarMul(a, b) ((float)(a) * (b)) +/** Returns the product of two SkScalars plus a third SkScalar +*/ +#define SkScalarMulAdd(a, b, c) ((float)(a) * (b) + (c)) +/** Returns the quotient of two SkScalars (a/b) +*/ +#define SkScalarDiv(a, b) ((float)(a) / (b)) +/** Returns the mod of two SkScalars (a mod b) +*/ +#define SkScalarMod(x,y) sk_float_mod(x,y) +/** Returns the product of the first two arguments, divided by the third argument +*/ +#define SkScalarMulDiv(a, b, c) ((float)(a) * (b) / (c)) +/** Returns the multiplicative inverse of the SkScalar (1/x) +*/ +#define SkScalarInvert(x) (SK_Scalar1 / (x)) +#define SkScalarFastInvert(x) (SK_Scalar1 / (x)) +/** Returns the square root of the SkScalar +*/ +#define SkScalarSqrt(x) sk_float_sqrt(x) +/** Returns b to the e +*/ +#define SkScalarPow(b, e) sk_float_pow(b, e) +/** Returns the average of two SkScalars (a+b)/2 +*/ +#define SkScalarAve(a, b) (((a) + (b)) * 0.5f) +/** Returns one half of the specified SkScalar +*/ +#define SkScalarHalf(a) ((a) * 0.5f) + +#define SK_ScalarSqrt2 1.41421356f +#define SK_ScalarPI 3.14159265f +#define SK_ScalarTanPIOver8 0.414213562f +#define SK_ScalarRoot2Over2 0.707106781f + +#define SkDegreesToRadians(degrees) ((degrees) * (SK_ScalarPI / 180)) +#define SkRadiansToDegrees(radians) ((radians) * (180 / SK_ScalarPI)) +float SkScalarSinCos(SkScalar radians, SkScalar* cosValue); +#define SkScalarSin(radians) (float)sk_float_sin(radians) +#define SkScalarCos(radians) (float)sk_float_cos(radians) +#define SkScalarTan(radians) (float)sk_float_tan(radians) +#define SkScalarASin(val) (float)sk_float_asin(val) +#define SkScalarACos(val) (float)sk_float_acos(val) +#define SkScalarATan2(y, x) (float)sk_float_atan2(y,x) +#define SkScalarExp(x) (float)sk_float_exp(x) +#define SkScalarLog(x) (float)sk_float_log(x) + +inline SkScalar SkMaxScalar(SkScalar a, SkScalar b) { return a > b ? a : b; } +inline SkScalar SkMinScalar(SkScalar a, SkScalar b) { return a < b ? a : b; } + +static inline bool SkScalarIsInt(SkScalar x) { + return x == (float)(int)x; +} // DEPRECATED : use ToInt or ToScalar variant -#define SkScalarFloor(x) SkScalarFloorToInt(x) -#define SkScalarCeil(x) SkScalarCeilToInt(x) -#define SkScalarRound(x) SkScalarRoundToInt(x) +#ifdef SK_SUPPORT_DEPRECATED_SCALARROUND +# define SkScalarFloor(x) SkScalarFloorToInt(x) +# define SkScalarCeil(x) SkScalarCeilToInt(x) +# define SkScalarRound(x) SkScalarRoundToInt(x) +#endif /** * Returns -1 || 0 || 1 depending on the sign of value: @@ -303,13 +222,7 @@ static inline bool SkScalarNearlyEqual(SkScalar x, SkScalar y, */ static inline SkScalar SkScalarInterp(SkScalar A, SkScalar B, SkScalar t) { SkASSERT(t >= 0 && t <= SK_Scalar1); - return A + SkScalarMul(B - A, t); -} - -static inline SkScalar SkScalarLog2(SkScalar x) { - static const SkScalar log2_conversion_factor = SkScalarDiv(1, SkScalarLog(2)); - - return SkScalarMul(SkScalarLog(x), log2_conversion_factor); + return A + (B - A) * t; } /** Interpolate along the function described by (keys[length], values[length]) @@ -329,7 +242,6 @@ SkScalar SkScalarInterpFunc(SkScalar searchKey, const SkScalar keys[], * Helper to compare an array of scalars. */ static inline bool SkScalarsEqual(const SkScalar a[], const SkScalar b[], int n) { -#ifdef SK_SCALAR_IS_FLOAT SkASSERT(n >= 0); for (int i = 0; i < n; ++i) { if (a[i] != b[i]) { @@ -337,9 +249,6 @@ static inline bool SkScalarsEqual(const SkScalar a[], const SkScalar b[], int n) } } return true; -#else - return 0 == memcmp(a, b, n * sizeof(SkScalar)); -#endif } #endif |