bb3c2b2498
Summary:
This PR is the C# version of 3a82d2b1a8
The above change moved Yoga away from NaN to facilitate usage of the `-ffast-math` compiler flag. However, that commit forgot to update the C# implementation.
Pull Request resolved: https://github.com/facebook/yoga/pull/817
Differential Revision: D10282642
Pulled By: shergin
fbshipit-source-id: 51681ce12344bc421f346ccc30e2950f4f39dbc6
42 lines
1.8 KiB
C#
42 lines
1.8 KiB
C#
/**
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* Copyright (c) Facebook, Inc. and its affiliates.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*/
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namespace Facebook.Yoga
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{
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public static class YogaConstants
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{
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/**
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* Large positive number signifies that the property(float) is undefined. Earlier we used to have
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* YGundefined as NAN, but the downside of this is that we can't use -ffast-math compiler flag as
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* it assumes all floating-point calculation involve and result into finite numbers. For more
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* information regarding -ffast-math compiler flag in clang, have a look at
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* https://clang.llvm.org/docs/UsersManual.html#cmdoption-ffast-math
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*/
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public const float Undefined = 10E20F;
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public static bool IsUndefined(float value)
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{
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// Value of a float in the case of it being not defined is 10.1E20. Earlier it used to be NAN,
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// the benefit of which
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// was that if NAN is involved in any mathematical expression the result was NAN. But since we
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// want to have `-ffast-math`
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// flag being used by compiler which assumes that the floating point values are not NAN and Inf,
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// we represent YGUndefined as 10.1E20.
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// But now if YGUndefined is involved in any mathematical operations this value(10.1E20) would
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// change.
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// So the following check makes sure that if the value is outside a range (-10E8, 10E8) then it
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// is undefined.
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return value >= 10E8F || value <= -10E8;
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}
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public static bool IsUndefined(YogaValue value)
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{
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return value.Unit == YogaUnit.Undefined;
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}
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}
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}
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